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SpaceX Vehicles and Missions => SpaceX Mega Thread Archive Section => Topic started by: Chris Bergin on 08/27/2016 04:41 pm

Title: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Chris Bergin on 08/27/2016 04:41 pm
Second thread for Dragon 2 updates.

Thread 1:
https://forum.nasaspaceflight.com/index.php?topic=35381.0

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News Articles:
https://www.nasaspaceflight.com/?s=%22Dragon+2%22
https://www.nasaspaceflight.com/tag/dragon-V2/

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Stay on topic and always be civil. These threads are very, very active so remember you're not just talking to other posters, but many thousands who are reading the posts.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: ScottMC on 10/01/2016 08:26 pm
Just absorbing the Mars presentation PDF (http://www.spacex.com/sites/spacex/files/mars_presentation.pdf) and noticed on page 38 references to PICA 3.0 advancements for Dragon 2, accompanied by this picture.  Is this a Dragon 2 heat shield (test article)?  Could those circular holes be for five little legs?

Quote from: SpaceX Mars Presentation
PICA 3.0 advancements for Dragon 2 enhance our ability to use the heat shield many times with minimal maintenance
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Zardar on 10/01/2016 09:04 pm
Just absorbing the Mars presentation PDF (http://www.spacex.com/sites/spacex/files/mars_presentation.pdf) and noticed on page 38 references to PICA 3.0 advancements for Dragon 2, accompanied by this picture.  Is this a Dragon 2 heat shield (test article)?  Could those circular holes be for five little legs?

Quote from: SpaceX Mars Presentation
PICA 3.0 advancements for Dragon 2 enhance our ability to use the heat shield many times with minimal maintenance

I'm more curious as to why the centre panel in the head shield is so square, given that all the other panels are more curved.

Looks almost hatch-shaped.......
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: gongora on 10/01/2016 09:54 pm
I'm more curious as to why the centre panel in the head shield is so square, given that all the other panels are more curved.

Looks almost hatch-shaped.......

That's not the center of the heat shield.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: eriblo on 10/01/2016 10:02 pm
That's a standard Dragon V1 heat shield, compare with a used one:  http://i.imgur.com/s7yORbX.jpg
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: MrHollifield on 10/02/2016 11:13 pm
Could those circular holes be for five little legs?

IANARS, but I think those are the S2 attach points.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Lars-J on 10/03/2016 12:51 am
Could those circular holes be for five little legs?

IANARS, but I think those are the S2 attach points.

Trunk attachment points. And there is six of them, it is camera perspective that makes it look like five.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: woods170 on 10/03/2016 02:06 pm
That's a standard Dragon V1 heat shield, compare with a used one:  http://i.imgur.com/s7yORbX.jpg
There is nothing that prevents SpaceX from using the Dragon 1 PICA layout for Dragon 2.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: eriblo on 10/03/2016 03:07 pm
That's a standard Dragon V1 heat shield, compare with a used one:  http://i.imgur.com/s7yORbX.jpg
There is nothing that prevents SpaceX from using the Dragon 1 PICA layout for Dragon 2.
Well of course not, it's a nice proven layout, but there should still be leg holes*. So it's either a Dragon 1 shield or they are forgoing legs, which they IMHO would only do if the first flights uses water splashdowns and there is a good reason as they want to move to land touchdowns (power assisted or fully powered) ASAP.

*Covered by (PICA?) plugs so not actual holes.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: woods170 on 10/03/2016 06:08 pm
That's a standard Dragon V1 heat shield, compare with a used one:  http://i.imgur.com/s7yORbX.jpg
There is nothing that prevents SpaceX from using the Dragon 1 PICA layout for Dragon 2.
Well of course not, it's a nice proven layout, but there should still be leg holes*. So it's either a Dragon 1 shield or they are forgoing legs, which they IMHO would only do if the first flights uses water splashdowns and there is a good reason as they want to move to land touchdowns (power assisted or fully powered) ASAP.

*Covered by (PICA?) plugs so not actual holes.
The first several flights of Dragon 2 for CCP are scheduled to splash down under parachutes, just like Dragon 1. Therefore, for the time being: no landing leg holes needed. The big exception will be Red Dragon, but that will be an extensively modified Dragon 2.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: eriblo on 10/03/2016 06:47 pm
That's a standard Dragon V1 heat shield, compare with a used one:  http://i.imgur.com/s7yORbX.jpg
There is nothing that prevents SpaceX from using the Dragon 1 PICA layout for Dragon 2.
Well of course not, it's a nice proven layout, but there should still be leg holes*. So it's either a Dragon 1 shield or they are forgoing legs, which they IMHO would only do if the first flights uses water splashdowns and there is a good reason as they want to move to land touchdowns (power assisted or fully powered) ASAP.

*Covered by (PICA?) plugs so not actual holes.
The first several flights of Dragon 2 for CCP are scheduled to splash down under parachutes, just like Dragon 1. Therefore, for the time being: no landing leg holes needed. The big exception will be Red Dragon, but that will be an extensively modified Dragon 2.
Yes, which is what I said. But they would need a good reason to do so as it would move heat shield redesign and, more importantly, validation of this new design until after the initial flights. Meaning that they would either have to fly it untested on a crewed mission (don't think that is going to happen), do a dedicated test flight or wait until a CRS2 Dragon 2 flight (if NASA agrees). All hints so far are that they are working on moving to land landings as early as possible.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: mfck on 10/03/2016 07:07 pm
That's a standard Dragon V1 heat shield, compare with a used one:  http://i.imgur.com/s7yORbX.jpg
There is nothing that prevents SpaceX from using the Dragon 1 PICA layout for Dragon 2.
Well of course not, it's a nice proven layout, but there should still be leg holes*. So it's either a Dragon 1 shield or they are forgoing legs, which they IMHO would only do if the first flights uses water splashdowns and there is a good reason as they want to move to land touchdowns (power assisted or fully powered) ASAP.

*Covered by (PICA?) plugs so not actual holes.
Do you, guys, have an idea why the attachment points symmetry is offset relative to the  shield layout symmetry?
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: cscott on 10/04/2016 01:16 am
Because the capsule re-enters at a positive angle of attack, to generate lift.  The heat shield is symmetric around the "nose" of the capsule as it re-enters "nose up".

EDIT: actually, probably symmetric about the zero angle-of-attack point (ie, oncoming airflow).  Presumably we'd call the geometric center of the heat shield the "nose", and it's not symmetric about that.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: SWGlassPit on 10/04/2016 02:02 am
I think the term you're looking for is "stagnation point"
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Comga on 10/04/2016 02:56 am
That's a standard Dragon V1 heat shield, compare with a used one:  http://i.imgur.com/s7yORbX.jpg (http://i.imgur.com/s7yORbX.jpg)

There is nothing that prevents SpaceX from using the Dragon 1 PICA layout for Dragon 2.

Well of course not, it's a nice proven layout, but there should still be leg holes*. So it's either a Dragon 1 shield or they are forgoing legs, which they IMHO would only do if the first flights uses water splashdowns and there is a good reason as they want to move to land touchdowns (power assisted or fully powered) ASAP.

*Covered by (PICA?) plugs so not actual holes.

The first several flights of Dragon 2 for CCP are scheduled to splash down under parachutes, just like Dragon 1. Therefore, for the time being: no landing leg holes needed. The big exception will be Red Dragon, but that will be an extensively modified Dragon 2.

(my emphasis)
or.... three or four of these also function as footpads that extend, or the centers of extending footpads.

These attach points are also heat shields.  They are just structural heat shields of a material too dense to use over the entire large bottom surface.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: OnWithTheShow on 10/04/2016 03:07 am
The first several flights of Dragon 2 for CCP are scheduled to splash down under parachutes, just like Dragon 1. Therefore, for the time being: no landing leg holes needed. The big exception will be Red Dragon, but that will be an extensively modified Dragon 2.

Why would a Red Dragon, or a regular Dragon 2 need legs? If the Super Dracos throttle satisfactorily why not just land on the heat shield?
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: gongora on 10/04/2016 03:20 am
The first several flights of Dragon 2 for CCP are scheduled to splash down under parachutes, just like Dragon 1. Therefore, for the time being: no landing leg holes needed. The big exception will be Red Dragon, but that will be an extensively modified Dragon 2.

Why would a Red Dragon, or a regular Dragon 2 need legs? If the Super Dracos throttle satisfactorily why not just land on the heat shield?

It's not a load-bearing sort of material.  You'd have to replace it every time.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: darkenfast on 10/04/2016 04:46 am
Red Dragon isn't coming back.  It's a one-way trip.  As long as the pressure hull isn't breached, it doesn't matter what happens to the heat shield.  Edit to add: Dragon 2 will need legs.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: rocx on 10/04/2016 07:24 am
The first several flights of Dragon 2 for CCP are scheduled to splash down under parachutes, just like Dragon 1. Therefore, for the time being: no landing leg holes needed. The big exception will be Red Dragon, but that will be an extensively modified Dragon 2.

Why would a Red Dragon, or a regular Dragon 2 need legs? If the Super Dracos throttle satisfactorily why not just land on the heat shield?

It's not a load-bearing sort of material.  You'd have to replace it every time.

Besides, the surface the Dragon is landing on might be uneven, so you can't be sure which part of the heat shield will touch the ground. So then all of the heat shield would have to be load-bearing and scratch-resistant, instead of just the soles of the feet.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: whitelancer64 on 10/04/2016 06:03 pm
Just a general question, does anyone here have any reason to think that the LAS on the Dragon would not have been sufficient to pull a crew away from the failing Amos-6 rocket?
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Johnnyhinbos on 10/04/2016 06:15 pm
There's about a dozen videos out there (including thread 1 of this topic) superimposing the dragon pad abort test with the AMOS-6 conflagration, demonstrating that the LAS would have worked. Elon also tweeted to that effect.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Lars-J on 10/04/2016 06:17 pm
Just a general question, does anyone here have any reason to think that the LAS on the Dragon would not have been sufficient to pull a crew away from the failing Amos-6 rocket?

Here in an overlay that shows how the LAS (if undamaged) should be sufficient: https://gfycat.com/RichNippyAnemonecrab
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: mfck on 10/04/2016 07:28 pm
Because the capsule re-enters at a positive angle of attack, to generate lift.  The heat shield is symmetric around the "nose" of the capsule as it re-enters "nose up".

EDIT: actually, probably symmetric about the zero angle-of-attack point (ie, oncoming airflow).  Presumably we'd call the geometric center of the heat shield the "nose", and it's not symmetric about that.

Thanks for taking time to answer, though I fear my question did not come through properly. Your explanation is about why the shield layout is not concentric with the capsule shape it covers.

My question was regarding the symmetry of the attach points, which is radial but is rotated about 10° as if not to align with the shield left-right or top-bottom symmetry axis.

P.S. My guess is that it's done to avoid tiles with too little area
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: whitelancer64 on 10/04/2016 07:58 pm
Thanks, johnny and Lars, the video overlays do seem convincing to me, however, I'm in an argument elsewhere with someone who is convinced they prove nothing. Specifically, he has said "in order for an abort system to have a chance of working you need advance warning (in the range of at least several seconds) and to get that warning you need to know what you are looking for and as of now SpaceX doesn’t."

So since SpaceX has not yet determined what the cause of the anomaly was, the computer system would not have been able to recognize that it should initiate a launch abort. He is also convinced that a launch abort system needs "several seconds" to initiate. He also seems to believe the capsule must be going supersonic within 0.1 seconds in order to get safely away from the fireball.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Lars-J on 10/04/2016 08:03 pm
Thanks, johnny and Lars, the video overlays do seem convincing to me, however, I'm in an argument elsewhere with someone who is convinced they prove nothing. Specifically, he has said "in order for an abort system to have a chance of working you need advance warning (in the range of at least several seconds) and to get that warning you need to know what you are looking for and as of now SpaceX doesn’t."

So since SpaceX has not yet determined what the cause of the anomaly was, the computer system would not have been able to recognize that it should initiate a launch abort. He is also convinced that a launch abort system needs "several seconds" to initiate. He also seems to believe the capsule must be going supersonic within 0.1 seconds in order to get safely away from the fireball.

I don't think an abort system would have much of a problem realizing that the upper stage it is sitting on is disintegrating. All power and communication lines have just been severed, and if that isn't a signal to abort - what is?  ;D And the advance warning of several seconds is just B.S., Super Draco engines can go to full thrust very quickly - on the order of milliseconds, not seconds.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: whitelancer64 on 10/04/2016 08:06 pm
Thanks, johnny and Lars, the video overlays do seem convincing to me, however, I'm in an argument elsewhere with someone who is convinced they prove nothing. Specifically, he has said "in order for an abort system to have a chance of working you need advance warning (in the range of at least several seconds) and to get that warning you need to know what you are looking for and as of now SpaceX doesn’t."

So since SpaceX has not yet determined what the cause of the anomaly was, the computer system would not have been able to recognize that it should initiate a launch abort. He is also convinced that a launch abort system needs "several seconds" to initiate. He also seems to believe the capsule must be going supersonic within 0.1 seconds in order to get safely away from the fireball.

I don't think an abort system would have much of a problem realizing that the upper stage it is sitting on is disintegrating. All power and communication lines have just been severed, and if that isn't a signal to abort - what is?  ;D And the advance warning of several seconds is just B.S., Super Draco engines can go to full thrust very quickly - on the order of milliseconds, not seconds.

That is precisely what I've been saying! To no avail, it seems. I should probably just let this one go.

And yes, a report from a few years back said from the signal to ignite to full thrust of the SuperDracos is less than 100 miliseconds. I've mentioned that, too, but again, deaf ears.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: SWGlassPit on 10/04/2016 08:18 pm
Saturn used a breakwire system to trigger aborts -- three wires running the length of the vehicle.  If two of them break (not counting staging), clearly something bad was happening and they would not go to space today, so an abort was triggered.  I don't know what the CCtCap providers use, but it's hard to beat that level of simplicity.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: DavidH on 10/04/2016 10:50 pm
Thanks, johnny and Lars, the video overlays do seem convincing to me, however, I'm in an argument elsewhere with someone who is convinced they prove nothing. Specifically, he has said "in order for an abort system to have a chance of working you need advance warning (in the range of at least several seconds) and to get that warning you need to know what you are looking for and as of now SpaceX doesn’t."

So since SpaceX has not yet determined what the cause of the anomaly was, the computer system would not have been able to recognize that it should initiate a launch abort. He is also convinced that a launch abort system needs "several seconds" to initiate. He also seems to believe the capsule must be going supersonic within 0.1 seconds in order to get safely away from the fireball.

I don't think an abort system would have much of a problem realizing that the upper stage it is sitting on is disintegrating. All power and communication lines have just been severed, and if that isn't a signal to abort - what is?  ;D And the advance warning of several seconds is just B.S., Super Draco engines can go to full thrust very quickly - on the order of milliseconds, not seconds.

That is precisely what I've been saying! To no avail, it seems. I should probably just let this one go.

And yes, a report from a few years back said from the signal to ignite to full thrust of the SuperDracos is less than 100 miliseconds. I've mentioned that, too, but again, deaf ears.
Welcome to Jim's world.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: hamerad on 10/04/2016 11:08 pm
I wonder how those people that think a dragon 2 wouldnt survive get around the fact that its capable of reentry and as such should be able to survive an explosion/fast fire for a few extra seconds until LAS activates.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Toast on 10/04/2016 11:42 pm
Specifically, he has said "in order for an abort system to have a chance of working you need advance warning (in the range of at least several seconds) and to get that warning you need to know what you are looking for and as of now SpaceX doesn’t."

Well, he's definitely wrong on several points. For starters, the Dragon capsule doesn't need to know what the failure is, or why it happened, it just needs to know that there was a failure. Although just to play devil's advocate, we don't know that the Dragon 2 would have aborted safely. We know that it is capable of doing so, but launch abort systems are one of the things that you hope you never have to use in the real world. The launch abort systems are both complex and tightly coupled, and I always fall back to the "Normal Accidents" model when there's conditions like that. During Three Mile Island, a faulty valve let emergency coolant flow out of the reactor, but wasn't caught because the status light for the valve showed that it was closed, and a temperature gauge that would have tipped off operators was ignored for multiple reasons that were only problematic in hindsight. Later in the cascade of events, a hydrogen bubble formed, which at the time some people in the industry didn't believe was actually possible. The system was built to be fault-tolerant, but the unforeseen interactions between systems allowed it to fail anyways. Similarly, launch abort systems are designed to be fault-tolerant and as simple as possible, but it's still something you'd rather never need to use, because the time scales involved preclude any human intervention should something go wrong.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: envy887 on 10/05/2016 12:24 am
Thanks, johnny and Lars, the video overlays do seem convincing to me, however, I'm in an argument elsewhere with someone who is convinced they prove nothing. Specifically, he has said "in order for an abort system to have a chance of working you need advance warning (in the range of at least several seconds) and to get that warning you need to know what you are looking for and as of now SpaceX doesn’t."

So since SpaceX has not yet determined what the cause of the anomaly was, the computer system would not have been able to recognize that it should initiate a launch abort. He is also convinced that a launch abort system needs "several seconds" to initiate. He also seems to believe the capsule must be going supersonic within 0.1 seconds in order to get safely away from the fireball.

It wasn't an explosion, and there no particular reason why a crewed dragon would need to get out of there instantly.

Dragon could have sat on the TEL for at least as long as the payload fairing did  (about 3 seconds if I recall correctly) with no adverse affects to the crew. That's a fairly benign environment compared to re-entry.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: whitelancer64 on 10/05/2016 05:48 pm

Welcome to Jim's world.

That is high praise! Thank you very much.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: DavidH on 10/05/2016 06:10 pm

Welcome to Jim's world.

That is high praise! Thank you very much.
Not really about the content of your post, just that no matter what insanity people KNOW is the truth, it's still not true but they argue it against his knowledge and experience all day long.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: uhuznaa on 10/11/2016 09:20 am
Thanks, johnny and Lars, the video overlays do seem convincing to me, however, I'm in an argument elsewhere with someone who is convinced they prove nothing. Specifically, he has said "in order for an abort system to have a chance of working you need advance warning (in the range of at least several seconds) and to get that warning you need to know what you are looking for and as of now SpaceX doesn’t."

So since SpaceX has not yet determined what the cause of the anomaly was, the computer system would not have been able to recognize that it should initiate a launch abort. He is also convinced that a launch abort system needs "several seconds" to initiate. He also seems to believe the capsule must be going supersonic within 0.1 seconds in order to get safely away from the fireball.

It wasn't an explosion, and there no particular reason why a crewed dragon would need to get out of there instantly.

Dragon could have sat on the TEL for at least as long as the payload fairing did  (about 3 seconds if I recall correctly) with no adverse affects to the crew. That's a fairly benign environment compared to re-entry.

Dragon, yes. I'm not too sure about the trunk surviving intact though. And Dragon needs the trunk to stabilize the trajectory when the LES fires. With a satellite there is the payload adapter at the bottom, but the trunk is just a hollow cylinder sitting on its rim on top of the second stage. An overpressure event could easily rip it apart. Much easier than damaging Dragon anyway.

Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: drzerg on 10/11/2016 08:46 pm
only way to destroy dragon on the pad is explosion sufficient to break capsule integrity via shockwave. temperature from burning kerosene is no way can do that. dragon only need trunk to stabilize its way AFTER les fires. it of course helps from the start but not critical.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Chris_Pi on 10/11/2016 08:54 pm
He is also convinced that a launch abort system needs "several seconds" to initiate. He also seems to believe the capsule must be going supersonic within 0.1 seconds in order to get safely away from the fireball.

It's probably like talking to a brick wall, But you might point out :

(1) The Little Joe Apollo LES test fired on it's own when the rocket broke up in flight unexpectedly and did so fast enough to work properly.

(2) An escape system that has to go 0-supersonic in a tenth of a second is pretty much guaranteed to be fatal. If this is needed there's no survivable way out anyways.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: eriblo on 10/11/2016 09:10 pm
He is also convinced that a launch abort system needs "several seconds" to initiate. He also seems to believe the capsule must be going supersonic within 0.1 seconds in order to get safely away from the fireball.

It's probably like talking to a brick wall, But you might point out :

(1) The Little Joe Apollo LES test fired on it's own when the rocket broke up in flight unexpectedly and did so fast enough to work properly.

(2) An escape system that has to go 0-supersonic in a tenth of a second is pretty much guaranteed to be fatal. If this is needed there's no survivable way out anyways.
Think you can remove "pretty much" - that's well over 300 g, aka pink jelly territory  :o
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: koshvv on 10/12/2016 02:19 am
Think you can remove "pretty much" - that's well over 300 g, aka pink jelly territory  :o
For at least it will be contained in spacesuits, so the capsule won't be stained.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Robotbeat on 10/12/2016 02:31 am
Think you can remove "pretty much" - that's well over 300 g, aka pink jelly territory  :o
For at least it will be contained in spacesuits, so the capsule won't be stained.
It'd crush the capsule, too. Heck, the engines would probably just rip right off the vehicle, so the crew would be okay. :D
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: acsawdey on 10/12/2016 02:59 am
Reminds me of this, which only accelerated at 100g:

https://www.youtube.com/watch?v=kvZGaMt7UgQ (https://www.youtube.com/watch?v=kvZGaMt7UgQ)

0 to Mach 10 in 5 seconds  :o

Definitely pink-jelly territory. Formula 1 drivers have walked away from crashes with peak deceleration in excess of 50g but the duration is rather shorter than what's needed for an escape system.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: docmordrid on 10/12/2016 04:58 am
In 1977 UK Formula One driver David Purley crashed at 173 kmh, stopping in 66 cm - 178g.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Chris_Pi on 10/12/2016 09:14 pm
Think you can remove "pretty much" - that's well over 300 g, aka pink jelly territory  :o

Didn't feel like double-checking it right then, And If I don't it always turns out I'm wrong about something.  ;D So "pretty much".
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: whitelancer64 on 10/12/2016 10:15 pm
The record seems to be 214 g in a racecar crash in 2003 by Kenny Bräck, though worth noting: "He suffered multiple fractures, breaking his sternum, femur, shattering a vertebra in his spine and crushing his ankles. He spent 18 months recovering from his injuries."

That said, I think we would all agree that sustaining high g forces would rapidly be lethal.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: renclod on 10/12/2016 10:29 pm

Dragon, yes. I'm not too sure about the trunk surviving intact though. ...just a hollow cylinder sitting on its rim on top of the second stage...

I guess most zero-zero abort scenarios consider a 1st stage RUD, not so much an upper stage issue. A LAS is a 90% insurance policy anyway, so yeah... a 3/4 trunk will probably quickly induce wild gyrations
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: envy887 on 10/12/2016 10:43 pm

Dragon, yes. I'm not too sure about the trunk surviving intact though. ...just a hollow cylinder sitting on its rim on top of the second stage...

I guess most zero-zero abort scenarios consider a 1st stage RUD, not so much an upper stage issue. A LAS is a 90% insurance policy anyway, so yeah... a 3/4 trunk will probably quickly induce wild gyrations

The fairing survived the anomaly quite well, and the trunk is similarly strong. I don't see it being an issue in this case.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: renclod on 10/12/2016 11:08 pm

The fairing survived the anomaly quite well, and the trunk is similarly strong. I don't see it being an issue in this case.

All right, per NASA standard when a LAS has to fire, it must save the day 9 out of 10. Strong trunk ? no dispute here.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: gongora on 10/13/2016 10:05 pm
Tweets from Jeff Foust: One (https://twitter.com/jeff_foust/status/786685656462426113) Two (https://twitter.com/jeff_foust/status/786686592077426688) Three (https://twitter.com/jeff_foust/status/786686995615641600) Four (https://twitter.com/jeff_foust/status/786687199261655040) Five (https://twitter.com/jeff_foust/status/786694587297456130l)

Quote
[Benji] Reed [SpaceX]: SpaceX has delivered 15,800 kg of cargo to ISS, returned 12,100 kg to date. 11 more missions remaining on CRS-1 contract.

Reed: we’ll use Dragon 2 for our CRS-2 missions, with propulsive landing (vs. splashdown). #ISPCS2016

Reed: we’ll re-fly our first Dragon capsule on the SpX-11 mission, so relatively soon. #ISPCS2016

Reed: reusing Dragon capsules will allow us to close down the Dragon 1 production line and focus on Dragon 2. #ISPCS2016

Reed: biggest issue for reusing Dragon was dealing with water intrusion. Worked hard to update capsule to avoid it. #ISPCS2016

Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: RoboGoofers on 10/14/2016 03:11 pm
What does 'water intrusion' entail? Is it water getting into the pressure vessel, or just water in cracks and crevices outside the pressure vessel?
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: king1999 on 10/14/2016 03:13 pm
What does 'water intrusion' entail? Is it water getting into the pressure vessel, or just water in cracks and crevices outside the pressure vessel?

Outside the pressure vessel but into the instruments and components around the bottom.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Herb Schaltegger on 10/14/2016 07:53 pm
What does 'water intrusion' entail? Is it water getting into the pressure vessel, or just water in cracks and crevices outside the pressure vessel?

Outside the pressure vessel but into the instruments and components around the bottom.

There was at least one CRS mission where water evidently entered the pressure vessel (probably through a cabin vent or pressure relief valve). That's the kind of thing they were most concerned with.

http://aviationweek.com/space/water-found-inside-dragon-after-splashdown
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: guckyfan on 10/14/2016 09:09 pm
What does 'water intrusion' entail? Is it water getting into the pressure vessel, or just water in cracks and crevices outside the pressure vessel?

Outside the pressure vessel but into the instruments and components around the bottom.

There was at least one CRS mission where water evidently entered the pressure vessel (probably through a cabin vent or pressure relief valve). That's the kind of thing they were most concerned with.

http://aviationweek.com/space/water-found-inside-dragon-after-splashdown

I think that was the easy part. Water getting into the pressure vessel is entirely unnecessary.

The problem was the "service section", the part below the pressure vessel. Someone on reddit who said he was an intern with SpaceX has worked on the problem. That section is not completely watertight and they installed something like a bilge pump that pumps water out and protects the interior.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Aerospace Dilettante on 10/16/2016 01:03 am

[Benji] Reed [SpaceX]:

Reed: we’ll use Dragon 2 for our CRS-2 missions, with propulsive landing (vs. splashdown). #ISPCS2016



Thought Musk or Shotwell had flat out said that they weren't going to make a cargo version of Dragon 2, though I applaud the decision as it will give them experience propulsively landing, perhaps enough to make NASA comfortable with the idea of allowing manned prop landings.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: docmordrid on 10/16/2016 02:17 am

[Benji] Reed [SpaceX]:

Reed: we’ll use Dragon 2 for our CRS-2 missions, with propulsive landing (vs. splashdown). #ISPCS2016


Thought Musk or Shotwell had flat out said that they weren't going to make a cargo version of Dragon 2, though I applaud the decision as it will give them experience propulsively landing, perhaps enough to make NASA comfortable with the idea of allowing manned prop landings.

IIRC CRS2 was originally going to use Dragon 1 for most flights for the CBM and Dragon 2 for fast return propulsive landings. IF the landing tests went (or go) well perhaps that's now inoperative. Need info if the upper mount now comes in NDA and CBM flavors
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: yg1968 on 10/16/2016 04:03 am
SpaceX gave NASA the option of Dragon1 or Dragon2 for CRS2. It's up to NASA to decide. It's possible that NASA prefers Dragon2.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: sdsds on 10/16/2016 05:56 am
Need info if the upper mount now comes in NDA and CBM flavors

Isn't it clear from an ISS operational perspective that all cargo flights need to be berthed at a CBM? Because the docking ports must be kept available for crew rotation vehicles?
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: guckyfan on 10/16/2016 06:30 am
Need info if the upper mount now comes in NDA and CBM flavors

Isn't it clear from an ISS operational perspective that all cargo flights need to be berthed at a CBM? Because the docking ports must be kept available for crew rotation vehicles?

There will be two ports and only 1 is strictly necessary for crew.

I think that both options with IDA and CBM are in the contract and NASA can call for the one they need for every flight. It would be usually IDA but if there is a bulky item that does not fit through IDA they can have a Dragon 1 with CBM too.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Roy_H on 10/16/2016 02:38 pm

[Benji] Reed [SpaceX]:

Reed: we’ll use Dragon 2 for our CRS-2 missions, with propulsive landing (vs. splashdown). #ISPCS2016



Thought Musk or Shotwell had flat out said that they weren't going to make a cargo version of Dragon 2, though I applaud the decision as it will give them experience propulsively landing, perhaps enough to make NASA comfortable with the idea of allowing manned prop landings.

My memory is quite different. I thought it was clear all along that Dragon 2 would replace Dragon 1 for both human and cargo versions. i.e. there would be a Dragon 2 variant with the CBM berthing port.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: yg1968 on 10/16/2016 06:05 pm
Cargo Dragon2 can only dock.

See below:

Kirk notes Dragon and Dragon 2 involved. "One berths, one docks"
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: yg1968 on 10/16/2016 06:14 pm
The CRS-2 contracts are posted here:

http://www.nasa.gov/centers/johnson/news/contracts/index.html
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: gongora on 10/16/2016 07:01 pm
The CRS-2 contracts are posted here:

http://www.nasa.gov/centers/johnson/news/contracts/index.html

All of the useful parts are redacted.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: uhuznaa on 10/17/2016 10:56 am
Does anybody know what SpaceX wants to do with the LES-propellants before splash-down? As far as I know at least the crewed Dragons will land on parachutes for quite a while, so you either dump/use the propellant or you land with full tanks.

Apollo dumped the RCS-propellants during descent, and smashing into the drink with a ton or so of hypergols right next to your elbow may not be a good idea. Or was NASA too cautious here?

You could either use them as a kind of third stage on ascent, use them for a deorbit burn, or be clever and do a simulated mid-air landing with them during descent. Outright dumping probably wouldn't be that clever, Apollo 15 lost one parachute when dumped RCS propellant ate the chute lines.

I'm a bit concerned that a parachute landing with full tanks may be no less dangerous than a propulsive landing. SpaceX starting with propulsive landings with cargo Dragons to learn some lessons and convince NASA would be great.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Lars-J on 10/17/2016 08:56 pm
Does anybody know what SpaceX wants to do with the LES-propellants before splash-down? As far as I know at least the crewed Dragons will land on parachutes for quite a while, so you either dump/use the propellant or you land with full tanks.

There are no LES specific tanks. Super-draco and draco engines are fed from the same set of tanks. So they would never land with the propellant tanks "full". Either it is all used up during an abort, or it is mostly used up during the mission and only a small part remains.

Quote
I'm a bit concerned that a parachute landing with full tanks may be no less dangerous than a propulsive landing. SpaceX starting with propulsive landings with cargo Dragons to learn some lessons and convince NASA would be great.

You don't have to be concerned, your premise is wrong.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: uhuznaa on 10/17/2016 10:03 pm
Does anybody know what SpaceX wants to do with the LES-propellants before splash-down? As far as I know at least the crewed Dragons will land on parachutes for quite a while, so you either dump/use the propellant or you land with full tanks.

There are no LES specific tanks. Super-draco and draco engines are fed from the same set of tanks. So they would never land with the propellant tanks "full". Either it is all used up during an abort, or it is mostly used up during the mission and only a small part remains.

Quote
I'm a bit concerned that a parachute landing with full tanks may be no less dangerous than a propulsive landing. SpaceX starting with propulsive landings with cargo Dragons to learn some lessons and convince NASA would be great.

You don't have to be concerned, your premise is wrong.

Ok... So where is the reserve for propulsive landings coming from when the propellants are used up during a normal mission? The LES or landing propellants should be at least about one order of magnitude more than the RCS propellants, and additionally to these. The delta-v requirements for LES or a landing are much, much higher than what a normal RCS needs (as in Dragon I) and at descent you'll have used up the RCS propellants anyway.

Or to put it more distinctively: When a propulsive landing is planned the engines are tested and only when they work as planned Dragon II proceeds to a propulsive landing. If not it lands with parachutes. At this moment though it will have about 0.5km/s worth of hypergolic propellants left in its tanks. That's quite a lot. Maybe one metric ton or more. I've read about up to two tons. What do they plan to do with all these hypergols if they need to deploy the chutes instead? Dump, burn, or splash down and hope for the best, possibly with some tank, valves or plumbing that failed, because if the engines didn't work as planned something must be broken?

I could understand NASA not being happy about that, that's why I'm asking. You'd be basically landing on a bomb (and with a ton more mass anyway) which negates the safety advantage of an inert capsule drifting down on chutes. When do they burn this off? During ascend adding 0.5km/s of delta-v? Deorbit? When?

Personally I'd prefer a propulsive landing over landing on a ton of hypergolics, chutes be damned. An inert capsule may be somewhat safer than a propulsive landing, but a capsule smashing down onto the water with a ton of hypergolics in its bottom isn't. SpaceX had water intrusion in the pressure vessel and had to install a bilge pump in the space where the propellant tanks and helium COPVs and valves and plumbings are. If you have ever dealt with a boat or ship you will know that water smashing at panels is nothing to be dealt lightly with. And this is a spacecraft, not a boat with a steel bow.

So I assume that a Dragon II that is planned to land on parachutes will do this with empty tanks. I really don't  see the RCS Dracos burning a ton of propellants without whizzing in circles around the ISS.
 
(I don't like to be told I'm wrong without being told what is right, preferably with some numbers in it, sorry.)
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Negan on 10/17/2016 10:14 pm
IIRC Dragon 2 was always supposed to be able to land with parachutes only if the Super-Dracos failed even on land. How is this any different than a water landing?

Edit: Here's an article that gives more info on this subject. http://www.nasaspaceflight.com/2014/08/dragon-v2-rely-parachutes-landing/

“The whole landing system is designed so that it’s survivable if there’s no propulsive assist at all.  So if you come down chutes only with the landing legs, we anticipate no crew injury. It’ll be kind of like landing in the Soyuz.”
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Khadgars on 10/17/2016 10:39 pm
He has a valid point though.  If they do not do a propulsive landing, what happens to the propellant?
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Lars-J on 10/17/2016 10:57 pm
Does anybody know what SpaceX wants to do with the LES-propellants before splash-down? As far as I know at least the crewed Dragons will land on parachutes for quite a while, so you either dump/use the propellant or you land with full tanks.

There are no LES specific tanks. Super-draco and draco engines are fed from the same set of tanks. So they would never land with the propellant tanks "full". Either it is all used up during an abort, or it is mostly used up during the mission and only a small part remains.

Quote
I'm a bit concerned that a parachute landing with full tanks may be no less dangerous than a propulsive landing. SpaceX starting with propulsive landings with cargo Dragons to learn some lessons and convince NASA would be great.

You don't have to be concerned, your premise is wrong.

Ok... So where is the reserve for propulsive landings coming from when the propellants are used up during a normal mission? The LES or landing propellants should be at least about one order of magnitude more than the RCS propellants, and additionally to these. The delta-v requirements for LES or a landing are much, much higher than what a normal RCS needs (as in Dragon I) and at descent you'll have used up the RCS propellants anyway.

Well... You can either believe it or not believe it. And no, the landing propellant is not an order of magnitude more than RCS. And just be clear, the "RCS" in this case is used for ALL orbital maneuvers. Orbit raising burns, de-orbit burns, in addition to the normal small maneuvers. Again, I'm not sure if you really understand how the Dragon 2 propellant tanks are set up. This is NOT (I repeat NOT) like Orion or CST-100, where each set of different thrusters has their own tanks.

Quote
Or to put it more distinctively: When a propulsive landing is planned the engines are tested and only when they work as planned Dragon II proceeds to a propulsive landing. If not it lands with parachutes. At this moment though it will have about 0.5km/s worth of hypergolic propellants left in its tanks. That's quite a lot. Maybe one metric ton or more.

0.5 km/s? The landing needs is probably less than half of that, the Dragon 2 is going to be subsonic and decelerating.

Quote
So I assume that a Dragon II that is planned to land on parachutes will do this with empty tanks. I really don't  see the RCS Dracos burning a ton of propellants without whizzing in circles around the ISS.
 
(I don't like to be told I'm wrong without being told what is right, preferably with some numbers in it, sorry.)

If you don't like the response, make less blanket assumptions. Especially when *your* numbers are pulled from thin air.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: uhuznaa on 10/17/2016 11:14 pm
IIRC Dragon 2 was always supposed to be able to land with parachutes only if the Super-Dracos failed even on land. How is this any different than a water landing?

Dragon II was always supposed to aim at a water landing at the coast, test the engines and then either divert to land on the ground with the engines or splash down in water with parachutes if there was something wrong with the engines. NASA than decided that they didn't want to have anything to do with the propulsive landings and wanted to land with parachutes in the water like capsules are supposed to land since ancient times.

They did buy the LES fueled by the same engines and the same fuel though. Now they're stuck with splashing down on a ton of unused hypergolics or (and that is what I'm wondering about) dumping/burning them off before even deploying the chutes to make sure that you don't hit the water on a ton of hypergolics next to your bum. I would really hate to do that and I guess NASA doesn't feel good about it too. Anybody who would feel good about this except in an emergency would need to be crazy.

Mind you, this WAS only meant to happen in an emergency (if the engines don't work), in which case it would be fine (using a backup landing system always is like attempted suicide to escape certain death), but somehow now a water landing is supposed to be the rule instead of the exception. So they either need to spend this fuel way before the landing or they will land on a bloody hypergolic bomb. Of course you can do some things to mitigate risks (like venting the high-pressure helium COPV tanks because these going off at a shock would be very bad news for the tanks with the hypergolic propellants right next to them), but this again means another point of failure, because some valves or pyros to vent the pressure vessels you need to pressurize your LES engines normally would be considered crazy too. These tanks are not meant to lose pressure in any other way than pressing fuel to the engines.

And that's why I'm asking at which point of the mission they want to get rid of these propellants or if they really want to splash down on them.

I could understand SpaceX to be fuming at NASA wanting to make the backup plan the rule and by this making things harder, but NASA is the customer and pays the bill.

SpaceX often is aggressively ambitious, but being that and then having safety blocks thrown in front of your feet doesn't make things easier.

Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: uhuznaa on 10/17/2016 11:39 pm
Well... You can either believe it or not believe it. And no, the landing propellant is not an order of magnitude more than RCS. And just be clear, the "RCS" in this case is used for ALL orbital maneuvers. Orbit raising burns, de-orbit burns, in addition to the normal small maneuvers. Again, I'm not sure if you really understand how the Dragon 2 propellant tanks are set up. This is NOT (I repeat NOT) like Orion or CST-100, where each set of different thrusters has their own tanks.


Ok, so please tell me how the tanks are set up (what does it matter how the tanks are set up?) and how much delta-v Dragon II needs for landing. After spending all the fuel for the RCS needs it will STILL have to have enough fuel for a propulsive landing. I don't care if this is half a ton or one ton or two. Half a ton of hypergolics when hitting the water is enough to make an big ugly orange fireball in the sea if there's a leak in plumbing or a valve giving way. Apollo didn't dump the little RCS fuel it had for no reason. Hitting the water is easily the hardest shock a capsule experiences during a flight, just as the front wheel coming down at landing was the driver for the stiffness of the shuttle fuselage. These are spacecraft, not boats. One Dragon had its pressure vessel taking on water on impact.

I agree that I don't have precise numbers. Do you? But when this thing is supposed to be able to do a propulsive landing it will have to have the propellants for that before deciding to either splash down or try a propulsive landing. And if it doesn't do a propulsive landing it will land with the fuel still on board.

Or it will have to dump or burn the fuel way before that and this was the only thing I was asking about in the first place. I don't want to argue. If you know it, tell me. If you want to discuss things, discuss. But don't tell me I'm wrong without telling me what's right.

Ah, forget it. I will go lurking again and come back in a year or so when Dragon may be actually landing, I have better things to do than to argue on a forum.

Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: IainMcClatchie on 10/18/2016 12:21 am
That's an interesting point about Apollo 15.  I hadn't heard that before.

The hypergol load isn't hard to figure out.  The Dragon 2 is supposed to be 8900 kg max on landing (6400 kg dry + 2500 kg return payload).  The SuperDracos are supposed to have 240s Isp.  So you just have to guess what the delta-V needed for landing is.  If the burn is 10 seconds long, that's 100 m/s of gravity loss, plus another 200 m/s or so to cancel Dragon 2's terminal velocity.

300 m/s delta-V is 1200 kg of propellant.

uhuznaa, I know you did this calc already.  I'm just pointing out that your guess of 1 tonne propellant isn't really just a guess.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Negan on 10/18/2016 05:11 pm
That's an interesting point about Apollo 15.  I hadn't heard that before.

The hypergol load isn't hard to figure out.  The Dragon 2 is supposed to be 8900 kg max on landing (6400 kg dry + 2500 kg return payload).  The SuperDracos are supposed to have 240s Isp.  So you just have to guess what the delta-V needed for landing is.  If the burn is 10 seconds long, that's 100 m/s of gravity loss, plus another 200 m/s or so to cancel Dragon 2's terminal velocity.

300 m/s delta-V is 1200 kg of propellant.

uhuznaa, I know you did this calc already.  I'm just pointing out that your guess of 1 tonne propellant isn't really just a guess.

Is there a requirement to launch with a full load of propellant?

Edit: Thinking about it since this is the LES propellant too, I guess yes it would so really Starliner would also have the same issue with regard to either burning it, dumping it, or landing with it.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: gongora on 10/18/2016 05:44 pm
Edit: Thinking about it since this is the LES propellant too, I guess yes it would so really Starliner would also have the same issue with regard to either burning it, dumping it, or landing with it.

Starliner is completely different system, they dump the service module.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Negan on 10/18/2016 05:50 pm
Edit: Thinking about it since this is the LES propellant too, I guess yes it would so really Starliner would also have the same issue with regard to either burning it, dumping it, or landing with it.

Starliner is completely different system, they dump the service module.

Thanks.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: whitelancer64 on 10/18/2016 06:04 pm
0.5 km/s is 1,100 mph

Terminal velocity for the Dragon, without parachutes, is going to be more like 250 mph. With parachutes it's more like 30 mph.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Negan on 10/18/2016 07:25 pm
How much propellant did the shuttle land with?
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: rpapo on 10/19/2016 03:27 pm
How much propellant did the shuttle land with?
Enough to where every landing was a hazmat situation, to some extent.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: sdsds on 10/19/2016 05:38 pm
Would there be anything preventing them from doing a burn to depletion just before parachute deployment?
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: rpapo on 10/19/2016 06:15 pm
Would there be anything preventing them from doing a burn to depletion just before parachute deployment?
Nothing, but that would leave nothing for a possible soft(er) landing.  And frankly, there's no reason I (at least) can think of why they couldn't just fire the upward pointing thrusters (not the SuperDracos) after landing until all the fuel is depleted.  The thrust wouldn't be enough to do anything, and by burning normally, all, or almost all the toxicity would be removed.

But you guys are worried about the tank cracking on landing...
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: IainMcClatchie on 10/19/2016 06:38 pm
0.5 km/s is 1,100 mph

Terminal velocity for the Dragon, without parachutes, is going to be more like 250 mph. With parachutes it's more like 30 mph.

If they are abandoning propulsive landing entirely, even as a backup, then you are quite right that there is no need to carry the required propellant all the way down to a landing.

You're right about the velocity too.  Even assuming it's 2 km up and aerobraking at 1.5 Gs, it'll be at 236 mph.  A 2.5 G landing burn (39% full thrust) would use around 175 m/s delta-V.  That's more reasonable than I expected.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: envy887 on 10/19/2016 06:41 pm
To my understanding, NASA only wants water landings for crew, which don't require a propulsive assist to soften the touchdown, so all the hypergols could be burned off or dumped prior to popping the chutes.

Propulsive assisted soft landings on dry land could dump/burn nearly all the hypergols before deploying the chutes, such that the landing assist burn consumes all but a small margin.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: docmordrid on 10/19/2016 07:22 pm
OTOH, if the parachutes fail you may want that propellant for an emergency propulsive landing - though ISTM, as someone who has had to use a reserve chute, the odds of success favor using the hypergolic rockets as the primary.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: AncientU on 10/19/2016 08:34 pm
OTOH, if the parachutes fail you may want that propellant for an emergency propulsive landing - though ISTM, as someone who has had to use a reserve chute, the odds of success favor using the hypergolic rockets as the primary.

Bet that was an 'interesting' day...

No matter which way Dragon 2 lands -- even if it land fully propulsively as designed -- it will have lots of hypergolic propellant remaining unless it finds a way to dump it without incurring additional risk.

Methinks the best plan is to land as designed, and use parachutes as a back-up.  Hopefully conservatism will not cause unintended (seriously bad) consequences as the program transitions from water to parachute with propulsive assist to full propulsive landings. 

Would Dream Chaser have been forced to do water landings, too?
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: whitelancer64 on 10/19/2016 08:40 pm
OTOH, if the parachutes fail you may want that propellant for an emergency propulsive landing - though ISTM, as someone who has had to use a reserve chute, the odds of success favor using the hypergolic rockets as the primary.

Bet that was an 'interesting' day...

No matter which way Dragon 2 lands -- even if it land fully propulsively as designed -- it will have lots of hypergolic propellant remaining unless it finds a way to dump it without incurring additional risk.

Methinks the best plan is to land as designed, and use parachutes as a back-up.  Hopefully conservatism will not cause unintended (seriously bad) consequences as the program transitions from water to parachute with propulsive assist to full propulsive landings. 

Would Dream Chaser have been forced to do water landings, too?

DreamChaser is the only one that could avoid a water landing, even a pad abort would allow it to pitch over and land on either the skid strip or Shuttle runway.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Negan on 10/19/2016 09:42 pm
Methinks the best plan is to land as designed, and use parachutes as a back-up.  Hopefully conservatism will not cause unintended (seriously bad) consequences as the program transitions from water to parachute with propulsive assist to full propulsive landings.

Crew Dragon was designed to be capable to land all three ways from the beginning. If there are unintended consequences, it's not because of the choice of landing method, but due to a design that failed to deliver.

Edit: The only real unintended consequence here is that SpaceX has to actually deliver a capability it already claimed to have which was "In the event of any anomalies with the propulsion system, Dragon retains its parachute capability for a soft water landing, a technology that has been demonstrated repeatedly via cargo missions."
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: guckyfan on 10/21/2016 07:45 am
The only real unintended consequence here is that SpaceX has to actually deliver a capability it already claimed to have which was "In the event of any anomalies with the propulsion system, Dragon retains its parachute capability for a soft water landing, a technology that has been demonstrated repeatedly via cargo missions."

That capability is needed for abort anyway. They can not skip the parachutes. Except for RedDragon.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Negan on 10/21/2016 05:19 pm
The only real unintended consequence here is that SpaceX has to actually deliver a capability it already claimed to have which was "In the event of any anomalies with the propulsion system, Dragon retains its parachute capability for a soft water landing, a technology that has been demonstrated repeatedly via cargo missions."

That capability is needed for abort anyway. They can not skip the parachutes. Except for RedDragon.

Who was talking about skipping parachutes?
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: guckyfan on 10/21/2016 08:24 pm
Who was talking about skipping parachutes?

Who would doubt Dragons ability to water landing? Cargo Dragon is doing it already.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: uhuznaa on 10/24/2016 05:58 pm
0.5 km/s is 1,100 mph

Terminal velocity for the Dragon, without parachutes, is going to be more like 250 mph. With parachutes it's more like 30 mph.

If they are abandoning propulsive landing entirely, even as a backup, then you are quite right that there is no need to carry the required propellant all the way down to a landing.

You're right about the velocity too.  Even assuming it's 2 km up and aerobraking at 1.5 Gs, it'll be at 236 mph.  A 2.5 G landing burn (39% full thrust) would use around 175 m/s delta-V.  That's more reasonable than I expected.

[De-lurking after a cool-off period]

First, I think propulsive landings if you have the fuel and engines for the LES anyway is a totally reasonable thing to do. More reasonable than landing on all that stuff.

Second: The needed delta-v for the LES case will be much higher and they will at least have to dump or burn the difference or all of it anyway.

That was what I was wondering about: If NASA accepts the liquid LES and insists in parachute landings, they WILL have to get rid of all those hypergols before splashdown or accept the risk of hitting the water with too much of that nasty stuff along with a plumber's nightmare of valves, pipes, propellant and high-pressure helium tanks and engines right where it hits the water. Even one helium COWPV giving way would rip all of this apart, with fatal consequences. OK, you could at least vent the helium, but even this adds another point of failure in an important subsystem. You don't want to have another valve in the LES.

And dumping the propellants before parachute deployment would be risky, because you would necessarily douse all of the craft with highly corrosive poison before deploying your parachute. Burning it would be better and then you can just as well do a simulated mid-air landing to do a free test of your propulsive landing concept. Just stop to zero velocity at altitude, save all the data and then start dropping again and then deploy your parachutes. But if this has to work anyway, why don't land on it to begin with instead of adding another landing system (parachutes) serially to it?

Or burn all of it either as a third stage during ascent or do the de-orbit burn of all de-orbit burns with it.

Ah, I just want to see that thing fly finally, that's all! But it would be more than ironic if NASA would accept the LES, then insist in parachute landings and then point at the fireball at splashdown and say "See? We TOLD you!".

I have always said that integrating liquid fueled LES and propulsive landings is aggressively ambitious, but if you do that at least pull through with it. Everything else is just adding more problems. Accept the risks and polish your design instead of avoiding them by adding even more things that have to work.


Sometimes I think that SpaceX is very much like NASA was in the good old days, when they went from not very much at all to the Moon in less than eight years. It certainly involved a bit of bravery, but "Das Glück ist mit den Tüchtigen" as the Germans say ("Fortune favours the bold"). I'm pretty sure today Wernher von Braun would hire with SpaceX instead of NASA. In fact his Mars plans in the 50s were not at all unlike ITS.





Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Flying Beaver on 11/28/2016 03:34 am
Dragon 2 on the deck of Just Read the Instructions?

Propulsive landing tests out in the pacific?  ;D

https://www.facebook.com/groups/spacexgroup/permalink/10154819972796318/
 
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: CorvusCorax on 11/28/2016 09:43 am
Why would you ever "dump" hypergolics in the atmosphere? Either you'd use them, for propulsive landing, or, if you decide to land on purpose on parachutes only, you'd take the deorbit burn to burn to near-depletion before atmospheric interface. (You need a bit of RCS thrust for reaction control during reentry itself but thats tiny compared to landing or deorbit burns)

You'd reenter both slower and lighter, reach terminal velocity sooner, and slower, and you don't need any extra burns/ dumping procedures.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: guckyfan on 11/28/2016 09:54 am
Why would you ever "dump" hypergolics in the atmosphere?

There would be at least that case where fully propulsive landing is planned but aborted for parachute landing at the last moment because of some malfunction of the SuperDraco. In that case they may want to dump propellant to become lighter and reduce the load of the parachutes.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Silmfeanor on 11/28/2016 10:00 am
Why would you ever "dump" hypergolics in the atmosphere?

There would be at least that case where fully propulsive landing is planned but aborted for parachute landing at the last moment because of some malfunction of the SuperDraco. In that case they may want to dump propellant to become lighter and reduce the load of the parachutes.

And also, in that case, to reduce the possibility of the inadvertent combustion of the hypergolics on landing. If you don't have it on the ship anymore, less chance of it rupturing/exploding. Soyuz burns off fuel as well while hanging below the chute.

Of course, a pin-point powered landing without parachute is preferable, so this might be an edge case.

Although I would not be that surprised if the currently-flying/flown Dragons use some draco thrusters to burn off hypergolics before splashdown; can't remember if they do or not.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: CorvusCorax on 11/28/2016 10:07 am
Just out of curiousity, what would happen if a sperdraco would be engaged after splashdown? Can the thrusters operate under water? ( to burn off leftover propellants post landing before recovery crews approach)
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Ronsmytheiii on 11/28/2016 03:49 pm
Dragon 2 on the deck of Just Read the Instructions?

Propulsive landing tests out in the pacific?  ;D

https://www.facebook.com/groups/spacexgroup/permalink/10154819972796318/
 

More likely testing water recovery for crew flights.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Prettz on 11/28/2016 04:44 pm
The extra weight of the superdraco fuel might be an issue, but would that fourth parachute they added be able to cover it?
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: whitelancer64 on 11/28/2016 05:33 pm
Just out of curiousity, what would happen if a sperdraco would be engaged after splashdown? Can the thrusters operate under water? ( to burn off leftover propellants post landing before recovery crews approach)

Rockets (in general) can operate under water, because they don't require the outside air to function, they use oxidizer they carry with them. Or in the case of monopropellants, they don't need an oxidizer.

However, I don't think the SuperDracos would be below the water line.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: matthewkantar on 11/28/2016 06:23 pm
Rockets (in general) can operate under water, because they don't require the outside air to function, they use oxidizer they carry with them. Or in the case of monopropellants, they don't need an oxidizer.

Starting with a bell full of incompressible matter may present some difficulties.

Matthew
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: mme on 11/28/2016 10:24 pm
Why would you ever "dump" hypergolics in the atmosphere? Either you'd use them, for propulsive landing, or, if you decide to land on purpose on parachutes only, you'd take the deorbit burn to burn to near-depletion before atmospheric interface. (You need a bit of RCS thrust for reaction control during reentry itself but thats tiny compared to landing or deorbit burns)

You'd reenter both slower and lighter, reach terminal velocity sooner, and slower, and you don't need any extra burns/ dumping procedures.
If the "test" firing of the SDs is off nominal during the landing sequence then the Dragon 2 will supposedly do an emergency parachute deployment.  I assume that is the scenario that people a thinking of.  But my non-aerospace-engineer opinion is that the hypergolics are safer in the their tanks then trying to vent them while under canopy.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: whitelancer64 on 11/29/2016 04:24 pm
Rockets (in general) can operate under water, because they don't require the outside air to function, they use oxidizer they carry with them. Or in the case of monopropellants, they don't need an oxidizer.

Starting with a bell full of incompressible matter may present some difficulties.

Matthew
Fair point. All underwater rockets I'm aware of have had the engines covered before ignition.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Req on 11/29/2016 06:30 pm
Dragon 2 on the deck of Just Read the Instructions?

Propulsive landing tests out in the pacific?  ;D

https://www.facebook.com/groups/spacexgroup/permalink/10154819972796318/
 

More likely testing water recovery for crew flights.

What role would the droneship play in those operations?  They've never taken it out for dragon recoveries in the past.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: old_sellsword on 11/29/2016 06:52 pm
Dragon 2 on the deck of Just Read the Instructions?

Propulsive landing tests out in the pacific?  ;D

https://www.facebook.com/groups/spacexgroup/permalink/10154819972796318/
 

More likely testing water recovery for crew flights.

What role would the droneship play in those operations?  They've never taken it out for dragon recoveries in the past.

According to The Roadie, it's not even a Dragon 2, its just a recovered CRS Dragon 1 that is still sitting on the dock. So they're more than likely just using the ASDS for storage since that dock is so tiny.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Raul on 11/30/2016 07:19 am
Dragon 2 on the deck of Just Read the Instructions?

Propulsive landing tests out in the pacific?  ;D

https://www.facebook.com/groups/spacexgroup/permalink/10154819972796318/
 

More likely testing water recovery for crew flights.

What role would the droneship play in those operations?  They've never taken it out for dragon recoveries in the past.

According to The Roadie, it's not even a Dragon 2, its just a recovered CRS Dragon 1 that is still sitting on the dock. So they're more than likely just using the ASDS for storage since that dock is so tiny.
Recovered CRS Dragon 1 is another one. Here (http://i.imgur.com/4FE0lwK.jpg) and here (http://imgur.com/a/VLrKX).

It's also unsure, if it is really on the ASDS deck. Fence seen in front the capsule it is not ASDS fence. There is also F9 booster stand beside on the right side on this picture (http://i.imgur.com/G3aP24j.jpg).

Capsule on Street View from July 2016 (https://www.google.cz/maps/@33.7212411,-118.2752353,3a,60.1y,30.18h,90.66t/data=!3m6!1e1!3m4!1s7yJUgtnf5FxM0iLizZe1hg!2e0!7i13312!8i6656?hl=en)

This capsule seems to be still the same as was seen earlier, I think.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: old_sellsword on 11/30/2016 12:08 pm
Dragon 2 on the deck of Just Read the Instructions?

Propulsive landing tests out in the pacific?  ;D

https://www.facebook.com/groups/spacexgroup/permalink/10154819972796318/
 

More likely testing water recovery for crew flights.

What role would the droneship play in those operations?  They've never taken it out for dragon recoveries in the past.

According to The Roadie, it's not even a Dragon 2, its just a recovered CRS Dragon 1 that is still sitting on the dock. So they're more than likely just using the ASDS for storage since that dock is so tiny.
Recovered CRS Dragon 1 is another one. Here (http://i.imgur.com/4FE0lwK.jpg) and here (http://imgur.com/a/VLrKX).

That's not what he thinks. The exact quote from the original Facebook post:

Quote
The white one is a recovery test article, as previously discussed. And the other one is a recovered CRS Cargo Dragon that used to be shrink wrapped in white but with a few holes, and they must have slapped a blue tarp over it in anticipation of winter rains.

Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Raul on 12/01/2016 11:50 am
That's not what he thinks. The exact quote from the original Facebook post:

Quote
The white one is a recovery test article, as previously discussed. And the other one is a recovered CRS Cargo Dragon that used to be shrink wrapped in white but with a few holes, and they must have slapped a blue tarp over it in anticipation of winter rains.

Simply I think we can see just white capsule with black bottom under blue tarp (http://i.imgur.com/uLKPAC0.jpg) - not shrink wrapped one. CRS D1 (http://i.imgur.com/4FE0lwK.jpg) is there shrink wrapped.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Salo on 12/13/2016 09:01 am
https://blogs.nasa.gov/commercialcrew/2016/12/12/nasas-commercial-crew-program-target-flight-dates/
Quote
SpaceX Demonstration Mission 1: November 2017
SpaceX Demonstration Mission 2: May 2018
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: JamesH65 on 12/13/2016 05:43 pm
There a statement on here that seems to have information I have not seen before - is it mostly nonsense?

http://forums.theregister.co.uk/forum/1/2016/12/13/spacex_delays_manned_dragon_capsule_launch/

Quote
I think this has virtually nothing to do with the AMOS-6 anomaly back in September but more to do with design problems in Dragon 2 itself. The explosion, whilst annoying, shouldn't have affected any of the Dragon 2 development critical paths. If anything it probably allowed more time on Dragon 2 during the investigation.
From what I understand, SpaceX have a fundamental set of problems with several components of the Dragon 2 craft and it's associated hardware. There are ongoing issues with stress fractures in the SuperDraco engines, along with crack issues in the tube used to dock and transfer items between it and the ISS. There have also been issues, apparently (source /r/SpaceX), with the SpaceX spacesuits currently under development. We know NASA have been kicking up a fuss with the whole "put astronauts on board the rocket first and then fuel" for months now, and the September event undoubtedly ruffled the feathers further in regards to that, but at the end of the day that's just a procedural hurdle to get over.
NASA has also further contributed to delays with Dragon 2 by insisting the first flights are splashdowns rather than using the SuperDraco assisted propulsive landing it was originally designed to do, that alone required an extensive redesign of many parts of the craft.
At the end of the day, schedules slip and there are problems, that's just how things are. I'd be interested to know how this is going to impact the Red Dragon mars mission currently scheduled for 2018 Mars synod though.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: gongora on 12/13/2016 06:06 pm
There a statement on here that seems to have information I have not seen before - is it mostly nonsense?

http://forums.theregister.co.uk/forum/1/2016/12/13/spacex_delays_manned_dragon_capsule_launch/

partly not understanding what they read (the stress fractures would be Merlin, not SD), partly out of date (the tunnel cracking on their first build should be solved by now), partly relevant (fueling concerns, maybe the turbopump stress fracture thing), partly hearsay (vague spacesuit problems sourced from Reddit?  Really?).  None of this is new, much of it is from the report mentioned here (https://forum.nasaspaceflight.com/index.php?topic=37802.msg1576831#msg1576831) and here (https://forum.nasaspaceflight.com/index.php?topic=37802.msg1577981#msg1577981).
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: old_sellsword on 12/13/2016 06:20 pm
There a statement on here that seems to have information I have not seen before - is it mostly nonsense?

http://forums.theregister.co.uk/forum/1/2016/12/13/spacex_delays_manned_dragon_capsule_launch/

All of the claims made in that repsonse you linked come from two places: a September OIG report on Commercial Crew progress (https://oig.nasa.gov/audits/reports/FY16/IG-16-028.pdf) and a recent WSJ article on SpaceX Commercial Crew delays. (http://www.wsj.com/articles/spacex-has-delayed-first-manned-nasa-launch-to-2018-from-2017-1481581294?mod=e2tw)

The first claim:

Quote from:  asphytxtc
There are ongoing issues with stress fractures in the SuperDraco engines,

I think the "stress fracture of SuperDracos" is actually a conflation of the two sources, and technically incorrect. The OIG report noted that "SpaceX has also experienced ongoing issues with stress fractures in turbopumps that must be resolved prior to flight." However, the WSJ article states "the report said the company faced 'ongoing issues with stress fractures' in a portion of its propulsion system 'that must be resolved prior to flight.'" People mistook "propulsion system" to be SuperDracos, when in fact only the Merlin turbopumps have seen stress fractures.

The next claim:

Quote from:  asphytxtc
along with crack issues in the tube used to dock and transfer items between it and the ISS.

This comes directly from the OIG report: "in January 2015, the tunnel that provides a passageway for astronauts and cargo between the Dragon and the ISS was reported to have cracked during the heat treatment phase of the manufacturing process. As a result, SpaceX delayed qualification testing by approximately one year to better align the tests as SpaceX moves toward certification."

Next:

Quote from:  asphytxtc
There have also been issues, apparently (source /r/SpaceX), with the SpaceX spacesuits currently under development.

While it was quoted in r/SpaceX, it originally comes from the WSJ article, which says "At SpaceX, over the years those challenges have ranged from problems with space suits..."

Next:

Quote from:  asphytxtc
NASA has also further contributed to delays with Dragon 2 by insisting the first flights are splashdowns rather than using the SuperDraco assisted propulsive landing it was originally designed to do, that alone required an extensive redesign of many parts of the craft.

This also comes from the OIG report: "SpaceX officials attributed the delays to capsule design challenges, specifically switching from a design that used a ground-based landing to a water-based landing design in the first year after contract award. This resulted in significant challenges, including complications with vendor components and the effectiveness of the integrated landing system designed to ensure parachutes work and the capsule does not take on excessive water after landing in the ocean."

Finally:

Quote from:  asphytxtc
We know NASA have been kicking up a fuss with the whole "put astronauts on board the rocket first and then fuel" for months now, and the September event undoubtedly ruffled the feathers further in regards to that, but at the end of the day that's just a procedural hurdle to get over.

This doesn't really need a source, there's been threads here (http://forum.nasaspaceflight.com/index.php?topic=41587.0) discussing the issue for a while.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: mme on 12/13/2016 09:01 pm
https://blogs.nasa.gov/commercialcrew/2016/12/12/nasas-commercial-crew-program-target-flight-dates/
Quote
SpaceX Demonstration Mission 1: November 2017
SpaceX Demonstration Mission 2: May 2018
From the blog, SpaceX Demonstration Mission 1 is uncrewed and Demonstration Mission 2 will fly with a crew.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: yg1968 on 12/28/2016 03:30 pm
This presentation on CRS2 was posted a couple of weeks ago:

https://www.youtube.com/watch?v=fjJzJPbBSOw
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: yg1968 on 12/28/2016 03:33 pm
At the 15:16 mark, there is a slide that says that all 6 CRS2 missions will be on Dragon 2 with propulsive landing!

Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Comga on 12/28/2016 03:43 pm
At the 15:16 mark, there is a slide that all 6 CRS2 missions will be on Dragon 2 with propulsive landing!

Another remarkable item on that slide is "significantly increased volume over Dragon 1 (CRS1)"
How is the volume increased (significantly!) without changing the pressure vessel?
Have they taken something out to make more room?
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: whitelancer64 on 12/28/2016 04:22 pm
At the 15:16 mark, there is a slide that all 6 CRS2 missions will be on Dragon 2 with propulsive landing!

Another remarkable item on that slide is "significantly increased volume over Dragon 1 (CRS1)"
How is the volume increased (significantly!) without changing the pressure vessel?
Have they taken something out to make more room?

The pressure vessel was changed, it's not the same as the Cargo Dragon.

Compare Cargo:

http://digitalvideo.8m.net/SpaceX/DragonRider/DragonPressureHull.jpg

With Crew:

https://www.nasa.gov/sites/default/files/thumbnails/image/27263296274_db0774f7be_o.jpg

You can see the barrel at the base is significantly longer.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: yg1968 on 12/28/2016 04:30 pm
Here is a presentation on commercial crew which was posted on YouTube a couple of weeks ago:

https://www.youtube.com/watch?v=8zzyuPNEfps
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Steven Pietrobon on 12/29/2016 06:13 am
Slides from the presentation.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: guckyfan on 12/29/2016 07:03 am
Have we seen the SuperDraco fired that close to the ground before? I am sure it was mentioned or was in one of the slides that they did it to test ground effects that could affect landing.

(http://forum.nasaspaceflight.com/index.php?action=dlattach;topic=41016.0;attach=1399063;image)
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Earendil on 12/29/2016 08:27 am
Sorry of this has been discussed before, but what happened with the solar panels on the trunk's surface?

All the new renders lack any solar panels which is unrealistic.. Or maybe they will go with something more standard - a la D1?
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: kevinof on 12/29/2016 08:36 am
Far as we know they are the "new style" - flush on the trunk walls. I suspect it's just the render isn't accurate.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Earendil on 12/29/2016 08:50 am
Oh, yes.
They mentioned it at 22:35 in the talk.

It is just that before they used to render 360 degrees solar wrapped trunk, and now there only a couple of solar areas on the trunk seen on some of the slides.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: eriblo on 12/29/2016 09:34 am
Oh, yes.
They mentioned it at 22:35 in the talk.

It is just that before they used to render 360 degrees solar wrapped trunk, and now there only a couple of solar areas on the trunk seen on some of the slides.
I'm not sure whether there was solar panels all the way around at some point but I think the plan has been half panels, half radiators for some time. Putting the panels on the back means that you don't need to have the windows facing the sun. A side effect is that very few renders then show them as the side with windows and a hatch is more photogenic (and in line with the whole "crewed" thing :) ).
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Earendil on 12/29/2016 09:39 am
Thanks for that elaboration.

I had a wrong impression obviously.

It was also great to learn that all CRS2 flights will be using D2 with propulsive landing.
I think it was assumed before, that D1 will continue flying.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: guckyfan on 12/29/2016 09:54 am
It was not clear if propulsive landing means fully propulsive or parachute with propulsive assist for touchdown. I hope it is fully propulsive.

It was also not mentioned if they use the berthing port or docking for cargo.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: ethan829 on 12/29/2016 11:43 am
Have we seen the SuperDraco fired that close to the ground before? I am sure it was mentioned or was in one of the slides that they did it to test ground effects that could affect landing.


Yes, back in April on Twitter and Instagram:


https://www.instagram.com/p/BEtt_Hsl8Vz/?taken-by=spacex


https://twitter.com/SpaceX/status/725395026583285761
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: gongora on 12/29/2016 02:08 pm
It was not clear if propulsive landing means fully propulsive or parachute with propulsive assist for touchdown. I hope it is fully propulsive.

It was also not mentioned if they use the berthing port or docking for cargo.

Docking for cargo, it's in the CRS presentation.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: sdsds on 12/30/2016 02:44 am
Docking for cargo, it's in the CRS presentation.

Yes. And from an outsider's perspective this is one of the first real indications that the tail is finally strong enough to wag the dog, even just a little. It had seemed like NASA "wanted" cargo vessels to berth, but that wasn't what the winning bid offered and NASA acquiesced.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: baldusi on 12/30/2016 03:27 am
Docking for cargo, it's in the CRS presentation.

Yes. And from an outsider's perspective this is one of the first real indications that the tail is finally strong enough to wag the dog, even just a little. It had seemed like NASA "wanted" cargo vessels to berth, but that wasn't what the winning bid offered and NASA acquiesced.

AIUI, the berthing requires a significant amount of crew time, so NASA wanted to keep a bit of both. With DreamChaser, Cygnus and HTV they would cover all CBM requirements. In fact, I was surprised the new Cygnus wasn't a docking version either.
The commonality between the cargo and crew version of Dragon only enhances the crew side of the equation. I also wonder if the short undock time and powered land landing of Dragon 2 would not also help in some very time critical cargo. DreamChaser still would give a much smoother ride, thou.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: yg1968 on 12/30/2016 03:55 am
Docking for cargo, it's in the CRS presentation.

Yes. And from an outsider's perspective this is one of the first real indications that the tail is finally strong enough to wag the dog, even just a little. It had seemed like NASA "wanted" cargo vessels to berth, but that wasn't what the winning bid offered and NASA acquiesced.

For CRS2, SpaceX actually gave NASA the choice between Dragon1 (which berths) and Dragon2 (which docks). NASA choose Dragon2.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: sdsds on 12/30/2016 04:10 am
For CRS2, SpaceX actually gave NASA the choice between Dragon1 (which berths) and Dragon2 (which docks). NASA choose Dragon2.

Do we know how they were priced? Was it that D2 provides the same or better value for less cost than D1?
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: yg1968 on 12/30/2016 04:18 am
For CRS2, SpaceX actually gave NASA the choice between Dragon1 (which berths) and Dragon2 (which docks). NASA choose Dragon2.

Do we know how they were priced? Was it that D2 provides the same or better value for less cost than D1?

I don't think that information was ever provided.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Comga on 12/30/2016 05:08 am
For CRS2, SpaceX actually gave NASA the choice between Dragon1 (which berths) and Dragon2 (which docks). NASA choose Dragon2.

Do we know how they were priced? Was it that D2 provides the same or better value for less cost than D1?

We were  just told  (http://forum.nasaspaceflight.com/index.php?topic=41016.msg1623766#msg1623766) that D2 has "substantially more volume" than D1, and we know that SpX flights are volume limited, not mass limited. 

More cargo through a narrower port might mean more astronaut time to unload and reload....
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: baldusi on 12/30/2016 01:49 pm
Compare the extra crew time needed for unloading (2hs?) vs the berthing crew time (~20hs?).
And we might be missing the critical number: downmass. Dragon 2 might have a bit more downmass, or better support for science payloads, thanks to the ECLSS.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: yg1968 on 12/30/2016 02:35 pm
This presentation on CRS2 was posted a couple of weeks ago:

link_https://www.youtube.com/watch?v=fjJzJPbBSOw

Here are the slides from the SpaceX CRS2 presentation:
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: DOCinCT on 12/30/2016 10:49 pm
Thanks for the slides.
 Any expansion on "significantly more cargo volume in D2 vs. D1? (significant should be more than a couple of cubic feet)
How likely is reuse of a D1 capsule on CRS11?  Has NASA signed off on that?
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: docmordrid on 12/30/2016 11:11 pm
The CRS2 max delivered payload volume requirement is 70 m3, so if the contract is for 6 flights that would require at least 11.7 m3 per flight. Let's say 12 m3 for a round number. Dragon 1 is listed as 10 m3, so a minimum of 20-25% larger?.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: AncientU on 12/31/2016 12:05 am
Thanks for the slides.
 Any expansion on "significantly more cargo volume in D2 vs. D1? (significant should be more than a couple of cubic feet)
How likely is reuse of a D1 capsule on CRS11?  Has NASA signed off on that?

100%

CRS-11 spacecraft must be ready to fly... it was originally scheduled to have flown in 2016, I believe.
I suspect that SpaceX isn't going to 'surprise' NASA with a reused vehicle; so yes, it has been 'signed-off' for probably more than a couple years now.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: dror on 12/31/2016 10:26 am
It was not clear if propulsive landing means fully propulsive or parachute with propulsive assist for touchdown. I hope it is fully propulsive.

It was also not mentioned if they use the berthing port or docking for cargo.

Docking for cargo, it's in the CRS presentation.

Do we know if this cargo D2 will use a short duration transfer like soyuz or two days transfer like D1?
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: clongton on 12/31/2016 01:26 pm
It was not clear if propulsive landing means fully propulsive or parachute with propulsive assist for touchdown. I hope it is fully propulsive.
It was also not mentioned if they use the berthing port or docking for cargo.
Docking for cargo, it's in the CRS presentation.
Do we know if this cargo D2 will use a short duration transfer like soyuz or two days transfer like D1?

For crew they might, but why bother for cargo?
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: DOCinCT on 12/31/2016 03:20 pm
It was not clear if propulsive landing means fully propulsive or parachute with propulsive assist for touchdown. I hope it is fully propulsive.
It was also not mentioned if they use the berthing port or docking for cargo.
Docking for cargo, it's in the CRS presentation.
Do we know if this cargo D2 will use a short duration transfer like soyuz or two days transfer like D1?
Is part of that 2 days trunk cargo?

For crew they might, but why bother for cargo?
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: kch on 12/31/2016 03:32 pm
It was not clear if propulsive landing means fully propulsive or parachute with propulsive assist for touchdown. I hope it is fully propulsive.
It was also not mentioned if they use the berthing port or docking for cargo.
Docking for cargo, it's in the CRS presentation.
Do we know if this cargo D2 will use a short duration transfer like soyuz or two days transfer like D1?

For crew they might, but why bother for cargo?

That does seem a bit much for cargo -- makes sense for crew.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: dror on 12/31/2016 05:37 pm

Do we know if this cargo D2 will use a short duration transfer like soyuz or two days transfer like D1?

For crew they might, but why bother for cargo?

For practice, I guess. And than some.
Didn't Progress ships bothered with that for a long while before Soyuz started doing that, and still do?
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: ClayJar on 12/31/2016 07:46 pm
Do we know if this cargo D2 will use a short duration transfer like soyuz or two days transfer like D1?
From what I've learned here on NSF (sadly, without a good link to an explanation by the experts here), the "slow" way only requires that you launch in plane.  The "fast" way requires that you launch in plane, but it also requires the ISS to be at a particular point in its orbit.  This requires maneuvering on the part of the ISS to make everything line up, and that means additional effort and using some of the ISS fuel reserves.

For cargo, there's generally not enough reason to require ISS maneuvers that cost the ISS fuel.  For crew, not being stuck in a cramped capsule for days generally *is* considered worthwhile.  (Also, cargo missions tend to outnumber crew missions.)
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: yg1968 on 12/31/2016 11:49 pm
Some captures from the presentation.

NASA. We don't think we could have lost another one. We have contingency supplies. For CRS-2 its about the same. A little more oversight for reliability and launching on time. A lot of complaints of the delays which is a big cost expense for the payloads. Station was prepared. Commercial payloads hurt more. Redundancy in CRS2. We did not overbuy. Capability to add missions if we need to. Launch on need capability. Bring up another vehicle quickly. Right now go with the missions we have if everything went according to plan. Have an ability to surge.

In case there was any doubt, this slide below confirms that cargo Dragon2 will dock and not berth.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Jcc on 01/01/2017 02:37 am
Thanks for the slides.
 Any expansion on "significantly more cargo volume in D2 vs. D1? (significant should be more than a couple of cubic feet)
How likely is reuse of a D1 capsule on CRS11?  Has NASA signed off on that?

100%

CRS-11 spacecraft must be ready to fly... it was originally scheduled to have flown in 2016, I believe.
I suspect that SpaceX isn't going to 'surprise' NASA with a reused vehicle; so yes, it has been 'signed-off' for probably more than a couple years now.

And, if you noticed in the CRS-2 video, it is stated that they will be able to "shut down the Dragon 1 production line" and concentrate on Dragon-2. The implication being that they will be able to fly out the remainder of CRS-1 missions with reused Dragon-1s.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Roy_H on 01/01/2017 03:02 am
...How likely is reuse of a D1 capsule on CRS11?  Has NASA signed off on that?

100%

CRS-11 spacecraft must be ready to fly... it was originally scheduled to have flown in 2016, I believe.
I suspect that SpaceX isn't going to 'surprise' NASA with a reused vehicle; so yes, it has been 'signed-off' for probably more than a couple years now.

And, if you noticed in the CRS-2 video, it is stated that they will be able to "shut down the Dragon 1 production line" and concentrate on Dragon-2. The implication being that they will be able to fly out the remainder of CRS-1 missions with reused Dragon-1s.

Or substitute Dragon 2 for some flights.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: guckyfan on 01/01/2017 07:13 am
Shutting down the production line IMO refers to making the pressure vessels. I understand that has been converted to producing Dragon 2 pressure vessels. They can reuse the old pressure vessels a lot by building up basically new Dragons from them.

So if NASA would need a cargo launch with a very large hatch they could provide a Dragon 1 under the CRS-2 contract. They would need a longer lead time and probably charge more.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: yg1968 on 01/01/2017 02:25 pm
I think that you are right. NASA orders each missions with a fairly long lead time. In the presentation, Ben Reed indicated that the options had been narrowed to Dragon 2. Given the fact that HTV, Cygnus and the first cargo DCs all berth, NASA can afford to have one cargo spacecraft that docks.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: yg1968 on 01/01/2017 02:28 pm
It was not clear if propulsive landing means fully propulsive or parachute with propulsive assist for touchdown. I hope it is fully propulsive.

It was also not mentioned if they use the berthing port or docking for cargo.

In the ISPCS 2016 CRS2 presentation, Angela Hart from NASA indicated that for cargo Dragon 2, propulsive landing was baselined from the outset (unlike crewed Dragon 2). To me that indicates that they will go straight to full propulsive landing.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: jtrame on 01/01/2017 02:32 pm
It was not clear if propulsive landing means fully propulsive or parachute with propulsive assist for touchdown. I hope it is fully propulsive.

It was also not mentioned if they use the berthing port or docking for cargo.

NASA indicated that for cargo Dragon 2 was baselined from the outset (unlike crewed Dragon 2). To me that indicates that they will get straight to full propulsive landing.

Smart to test propulsive landings using the returning cargo Dragon 2's since that is their ultimate goal with crew Dragon 2. 
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: yg1968 on 01/03/2017 09:04 pm
See below, 4 more commercial crew post-certification missions awarded to each of SpaceX and Boeing:

Mission Awards Secure Commercial Crew Transportation for Coming Years:
https://www.nasa.gov/feature/mission-awards-secure-commercial-crew-transportation-for-coming-years

Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: rockets4life97 on 01/03/2017 09:29 pm
Interesting that they were awarded equally. I thought SpaceX might take an extra mission or 2 from Boeing because they were cheaper.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: yg1968 on 01/03/2017 09:49 pm
Interesting that they were awarded equally. I thought SpaceX might take an extra mission or 2 from Boeing because they were cheaper.

I am not surprised. NASA really wanted redundancy for commercial crew even if it means paying more for it. 
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Oersted on 01/04/2017 05:09 am
It was not clear if propulsive landing means fully propulsive or parachute with propulsive assist for touchdown. I hope it is fully propulsive.

It was also not mentioned if they use the berthing port or docking for cargo.

NASA indicated that for cargo Dragon 2 was baselined from the outset (unlike crewed Dragon 2). To me that indicates that they will get straight to full propulsive landing.

Smart to test propulsive landings using the returning cargo Dragon 2's since that is their ultimate goal with crew Dragon 2.

SpaceX has always been good at testing untried technologies while fulfilling the requirements of their customers: witness the many booster propulsive landing attempts. Testing paid by the customers. Smart indeed (except when they tested fuelling).
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: woods170 on 01/04/2017 08:17 am
Interesting that they were awarded equally. I thought SpaceX might take an extra mission or 2 from Boeing because they were cheaper.
Nothing surprising about SpaceX and Boeing being awarded equally. The maximum number of post-certification flights covered under the CCtCAP contract is equal for both companies: 6
Both companies have now been awarded that maximum number of post-certification flights. SpaceX would not and could not get extra missions (because they are cheaper) under the terms of the current CCtCAP agreement. Any additional missions for either company would require either re-negotiation of the CCtCAP agreement (for example: an extension) and/or a new agreement (much like CRS-2 succeeded CRS-1).
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Star One on 01/04/2017 08:19 am
Interesting that they were awarded equally. I thought SpaceX might take an extra mission or 2 from Boeing because they were cheaper.

I am not surprised. NASA really wanted redundancy for commercial crew even if it means paying more for it.

Good to see not everything comes down to price. As a general point too many things have been screwed up longer term that I've seen by going for the lowest price as the only deciding factor.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: woods170 on 01/04/2017 09:18 am
Interesting that they were awarded equally. I thought SpaceX might take an extra mission or 2 from Boeing because they were cheaper.

I am not surprised. NASA really wanted redundancy for commercial crew even if it means paying more for it.

Good to see not everything comes down to price. As a general point too many things have been screwed up longer term that I've seen by going for the lowest price as the only deciding factor.
That was clear from the CCtCAP awards in september 2014. Boeing's proposal for CST-100 was by far the most expensive and yet it still was chosen by NASA because it was also the most complete and most mature solution. Price was A factor, but not THE factor. In fact, there was no such thing as THE factor. It was a combination of factors. But I digress.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Star One on 01/04/2017 10:16 am
Interesting that they were awarded equally. I thought SpaceX might take an extra mission or 2 from Boeing because they were cheaper.

I am not surprised. NASA really wanted redundancy for commercial crew even if it means paying more for it.

Good to see not everything comes down to price. As a general point too many things have been screwed up longer term that I've seen by going for the lowest price as the only deciding factor.
That was clear from the CCtCAP awards in september 2014. Boeing's proposal for CST-100 was by far the most expensive and yet it still was chosen by NASA because it was also the most complete and most mature solution. Price was A factor, but not THE factor. In fact, there was no such thing as THE factor. It was a combination of factors. But I digress.

I call that good decision making. But that's enough OT from me.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Robotbeat on 01/04/2017 01:00 pm
I'm not sure if call Starliner the most complete and mature at that time. The launch vehicle definitely was, but not the spacecraft. In spite of paper milestones, they had fundamental problems in the design, for instance the aerodynamic instability that recently surfaced.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: woods170 on 01/04/2017 02:16 pm
I'm not sure if call Starliner the most complete and mature at that time. The launch vehicle definitely was, but not the spacecraft. In spite of paper milestones, they had fundamental problems in the design, for instance the aerodynamic instability that recently surfaced.
The proposal at the time was deemed, by the NASA selecting officer (and we all know who that was), to be the most mature and complete. That proposal was basically all paperwork and the results of the risk-reduction work done in prior CCP phases. Mind you, the SpaceX and Sierra Nevada proposals were just as much "paper" at the time.

What happened to Boeing is a classical mistake: start constructing your spacecraft only after you have fully completed the design, in stead of having your design informed and evolved by building prototypes. As a result, the overweight issue was discovered fairly late in the process and thus so was the indirectly resulting aerodynamic issue.

What I'm trying to say is that physical reality will beat powerpoint theory every single time. A proposal maybe rock-solid on paper but less-than-stellar when metal is being bent.

Btw. This must be some sort of first: a Starliner discussion contaminating a SpaceX thread (in stead of the other way around) :)
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: yg1968 on 01/04/2017 02:27 pm
NASA preferred Boeing's way of doing things (it's paperwork trail, etc.) but I don't think that Gerst actually claimed that CST-100 was ahead of Dragon 2 in the Source Selection Statement.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: TrevorMonty on 01/04/2017 02:39 pm
It was not clear if propulsive landing means fully propulsive or parachute with propulsive assist for touchdown. I hope it is fully propulsive.

It was also not mentioned if they use the berthing port or docking for cargo.

NASA indicated that for cargo Dragon 2 was baselined from the outset (unlike crewed Dragon 2). To me that indicates that they will get straight to full propulsive landing.

Smart to test propulsive landings using the returning cargo Dragon 2's since that is their ultimate goal with crew Dragon 2.

SpaceX has always been good at testing untried technologies while fulfilling the requirements of their customers: witness the many booster propulsive landing attempts. Testing paid by the customers. Smart indeed (except when they tested fuelling).
The scientist with their life's work in return cargo may not think it a smart move, especially if it's first flight.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: yg1968 on 01/04/2017 02:45 pm
During the ISPCS 2016 presentation, Ben Reed of SpaceX made it clear that propulsive landing under CRS2 is being done in order to get the samples quicker to researchers, not in order to test the technology.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Johnnyhinbos on 01/04/2017 03:07 pm
During the ISPCS 2016 presentation, Ben Reed of SpaceX made it clear that propulsive landing under CRS2 is being done in order to get the samples quicker to researchers, not in order to test the technology.
Naturally. What else would he say? That's just good wordsmithing. However the point isn't lost that they will be also be generating valuable data and experience with propulsive landings along the way. It's just not overtly touted because it's adding a % of risk to the returned payload that wouldn't exist if it was strictly under 'chutes alone.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: yg1968 on 01/04/2017 03:14 pm
During the ISPCS 2016 presentation, Ben Reed of SpaceX made it clear that propulsive landing under CRS2 is being done in order to get the samples quicker to researchers, not in order to test the technology.
Naturally. What else would he say? That's just good wordsmithing. However the point isn't lost that they will be also be generating valuable data and experience with propulsive landings along the way. It's just not overtly touted because it's adding a % of risk to the returned payload that wouldn't exist if it was strictly under 'chutes alone.

If it was chutes alone, Dragon 2 would have to land in the ocean. So you wouldn't get the +3 hours bonus under CRS2. So there is business and scientific reasons for it.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: clongton on 01/04/2017 04:14 pm
The scientist with their life's work in return cargo may not think it a smart move, especially if it's first flight.

Spaceflight is risky - at best.
If you cannot afford to loose your investment then don't play the game.
Find another line of work.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Jim on 01/04/2017 04:46 pm
Spaceflight is risky - at best.
If you cannot afford to loose your investment then don't play the game.
Find another line of work.

No, they, the scientists, aren't suppose to take these risks.  Their risk is in the experiment itself and not how the experiment gets delivered or returned to them.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: eriblo on 01/04/2017 04:46 pm
During the ISPCS 2016 presentation, Ben Reed of SpaceX made it clear that propulsive landing under CRS2 is being done in order to get the samples quicker to researchers, not in order to test the technology.
Naturally. What else would he say? That's just good wordsmithing. However the point isn't lost that they will be also be generating valuable data and experience with propulsive landings along the way. It's just not overtly touted because it's adding a % of risk to the returned payload that wouldn't exist if it was strictly under 'chutes alone.
They also remove a % of risk to the returned payload that would exist if it was strictly under 'chutes alone, i.e. deployment and recovery at sea. As for the crewed case it can be argued that propulsive landing with parachute backup is safer as well as more convenient.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: clongton on 01/04/2017 05:08 pm
Spaceflight is risky - at best.
If you cannot afford to loose your investment then don't play the game.
Find another line of work.
No, they, the scientists, aren't suppose to take these risks.  Their risk is in the experiment itself and not how the experiment gets delivered or returned to them.

Respectfully disagree. Those scientists know what launch vehicle their experiments will be flying on. They know the limits of the spacecraft their experiments will be carried and returned in. They have to design their experiments to stay within the limits of those vehicles. So they DO take the risk. They are not unmindful of it. A not insignificant percentage of those launches will fail, and of those launches that do succeed an additional percentage of those spacecraft will fail in their mission in some fashion. For experiments that must be returned there is the additional risk of LOV during the EDL. The very real possibility of suffering a total loss is carefully considered at every step in the scientist's design process and steps are taken to mitigate that loss as much as possible. But loss happens anyway.

Risk is part of the lifestyle. It comes with the territory. Failure is not an uncommon experience. Every scientist in this business knows that and they choose to take that risk anyway. So I say again - if one is so invested in their experiment that they cannot afford to loose that investment then they are in the wrong line of work. Failure is not an option - it is a fact of life.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Jim on 01/04/2017 06:21 pm

Respectfully disagree. Those scientists know what launch vehicle their experiments will be flying on. They know the limits of the spacecraft their experiments will be carried and returned in.

Wrong.  They don't have to take the risk for new launch vehicle or spacecraft operations.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: yg1968 on 01/04/2017 07:36 pm

Respectfully disagree. Those scientists know what launch vehicle their experiments will be flying on. They know the limits of the spacecraft their experiments will be carried and returned in.

Wrong.  They don't have to take the risk for new launch vehicle or spacecraft operations.

Under CRS2, SpaceX gave NASA the choice between Dragon1 which splashes in the ocean (Mission Option A) and Dragon2 with propulsive landing (Mission Option B). NASA choose Dragon2.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: woods170 on 01/05/2017 09:12 am
Spaceflight is risky - at best.
If you cannot afford to loose your investment then don't play the game.
Find another line of work.

No, they, the scientists, aren't suppose to take these risks.  Their risk is in the experiment itself and not how the experiment gets delivered or returned to them.
I agree that scientists are not supposed to take these risks. However, that does not prevent them from sometimes actually taking that risk. That is how some folks lost Cluster for example. But also how others got their sloshing data back just fine. It's a matter of perception Jim. Not every scientist does things the way you think they should be done.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Jim on 01/05/2017 01:08 pm
Spaceflight is risky - at best.
If you cannot afford to loose your investment then don't play the game.
Find another line of work.

No, they, the scientists, aren't suppose to take these risks.  Their risk is in the experiment itself and not how the experiment gets delivered or returned to them.
I agree that scientists are not supposed to take these risks. However, that does not prevent them from sometimes actually taking that risk. That is how some folks lost Cluster for example. But also how others got their sloshing data back just fine. It's a matter of perception Jim. Not every scientist does things the way you think they should be done.

I am talking about scientists that are flying experiments to and from the ISS.  Their payloads should not be on risky untried spacecraft and operations.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: yg1968 on 01/05/2017 01:29 pm
Spaceflight is risky - at best.
If you cannot afford to loose your investment then don't play the game.
Find another line of work.

No, they, the scientists, aren't suppose to take these risks.  Their risk is in the experiment itself and not how the experiment gets delivered or returned to them.
I agree that scientists are not supposed to take these risks. However, that does not prevent them from sometimes actually taking that risk. That is how some folks lost Cluster for example. But also how others got their sloshing data back just fine. It's a matter of perception Jim. Not every scientist does things the way you think they should be done.

I am talking about scientists that are flying experiments to and from the ISS.  Their payloads should not be on risky untried spacecraft and operations.

By that standard, cargo Dream Chaser shouldn't have been chosen either.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: meekGee on 01/05/2017 03:14 pm
Spaceflight is risky - at best.
If you cannot afford to loose your investment then don't play the game.
Find another line of work.

No, they, the scientists, aren't suppose to take these risks.  Their risk is in the experiment itself and not how the experiment gets delivered or returned to them.
I agree that scientists are not supposed to take these risks. However, that does not prevent them from sometimes actually taking that risk. That is how some folks lost Cluster for example. But also how others got their sloshing data back just fine. It's a matter of perception Jim. Not every scientist does things the way you think they should be done.

I am talking about scientists that are flying experiments to and from the ISS.  Their payloads should not be on risky untried spacecraft and operations.

By that standard, cargo Dream Chaser shouldn't have been chosen either.

Nor Boeing's DreamLiner, given that Dragon at least is flying.

That whole argument has only one logical conclusion, and that's stagnation and glacial development rates.

It came up with Falcon.  Why go to 1.1?  Customers will run away since "you're wasting their time and money with these reusability experiments".

Same with F1.2

Customers are not running away, even after the failure.

Thing is, even if you separate development from flight, how many test-flights will you require?  The Falcon failures did not happen in the first or second flights, so how would test flights have helped?

Customers recognize that, and I am sure so do the scientists.  As was stated above - it was NASA's choice to make.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Jim on 01/05/2017 03:32 pm

By that standard, cargo Dream Chaser shouldn't have been chosen either.

No, experiments don't have to fly on the early missions until the vehicle is proved out.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Jim on 01/05/2017 03:39 pm

Customers recognize that, and I am sure so do the scientists.  As was stated above - it was NASA's choice to make.

Wrong.  It is not the same thing.  A comsat customer has insurance.  A scientist doesn't have the equivalent.   A scientist that has an experiment in zero g for 6-12 months and all his research is dependent on receiving and analyzing the samples after landing has no recourse.  Insurance isn't going to replace the sample or extend his grant.

Early missions of new spacecraft can just deliver common logistics items and not high value items or experiment samples.  This is what was done on the first couple of Dragons and Cygnus.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: edkyle99 on 01/05/2017 03:59 pm
Customers are not running away, even after the failure.
There is a discussion in another thread (in the SpaceX section) about this, with evidence that Arianespace has been gaining market share during the past year or two.

 - Ed Kyle
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Robotbeat on 01/05/2017 04:18 pm
SpaceX has had significant year on year launch rate growth for several years now. Is Ariane taking market share evidence of a growing commercial market? Or did SpaceX just have a burst of orders that filled up their manifest so new customers would have to wait?
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: envy887 on 01/05/2017 04:21 pm
Do all cargo Dragon returns carry high value items? Those were unproven at one point.

I.e. doesn't this statement:

No, experiments don't have to fly on the early missions until the vehicle is proved out.

apply to returns just as it does for launches?
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: meekGee on 01/05/2017 04:22 pm
Customers are not running away, even after the failure.
There is a discussion in another thread (in the SpaceX section) about this, with evidence that Arianespace has been gaining market share during the past year or two.

 - Ed Kyle
That may be.  Like in any business, if you invest in your future, your balance sheet will be a lighter shade of black.

But you still have to do it, or else you'll end up stagnated.

--

As for insurance, change my original statement to "customers and insurers", and it still stands, though as I just said, even if some are keeping away, it's still good corporate governance (to innovate) as long as you don't lose the company.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: abaddon on 01/05/2017 04:26 pm
I am talking about scientists that are flying experiments to and from the ISS.  Their payloads should not be on risky untried spacecraft and operations.
You mean like Cygnus on Atlas V?  By your standards, only HTV qualifies, so I guess scientists should get used to waiting a really long time for their experiments to get flown.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Jim on 01/05/2017 04:34 pm
You mean like Cygnus on Atlas V? .

No, both were proven separately. 

The point is that Antares flew a demo flight and then Cygnus flew a demo flight.  There was non critical hardware on the Cygnus.

and same for Spacex with COTS Demo Flight 1 & 2
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: abaddon on 01/05/2017 04:43 pm
No, both were proven separately. 

The point is that Antares flew a demo flight and then Cygnus flew a demo flight.  There was non critical hardware on the Cygnus.

and same for Spacex with COTS Demo Flight 1 & 2
Well, I suppose that is fair enough.  So you would say that 1st flight of any cargo mission using Dragon V2 or DreamChaser should include only low-value cargo as up and downmass?  That seems like it should be relatively straightforward to do logistically, and would retire any concerns about losing valuable science or cargo on an unproven vehicle.

That said, so far the cargo delivery failures to ISS have all been on "proven" vehicles (Soyuz/Progress, Falcon 9/Dragon, Antares/Cygnus) and Cygnus/Atlas V was right on the edge of being lost despite both vehicles being "proven".  Sample size on first flights is small, but I'm not really sure I see a convincing argument that they are riskier.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: matthewkantar on 01/05/2017 08:08 pm
If these scientists don't like how NASA is managing the risk in down mass, they can go to some other space station. An important job for NASA is to push technology forward. Risk is a part of this, managing risk should not hamper innovation.

Matthew
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Coastal Ron on 01/05/2017 08:17 pm
By that standard, cargo Dream Chaser shouldn't have been chosen either.

No, experiments don't have to fly on the early missions until the vehicle is proved out.

That's just an example of prioritizing risk, since someone's experiments will likely go down on the early missions.

And I don't agree that scientists aren't aware or concerned with the entire supply chain they depend upon - and they should be.  But then it's up to their project and NASA to decide how the logistics and risk will be handled.

I'm not sure how this is any different than when people and experiments flew on the Shuttle...
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Jim on 01/05/2017 08:52 pm

1.  That's just an example of prioritizing risk, since someone's experiments will likely go down on the early missions.

2.  I'm not sure how this is any different than when people and experiments flew on the Shuttle...

1.  No, experiments don't have to be returned with every vehicle.

2.  This discussion is about new vehicles and not hindsight.  No real payloads flew on the first 4 shuttle missions.  The perception about shuttle safety at the time vs now is not part of the discussion.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Johnnyhinbos on 01/06/2017 02:22 am
Just to keep a level playing field, this conversation is the analog of the elevator shaft conversation on the Boca Chica thread. But, by all means, keep going! :-)
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Lar on 01/06/2017 05:02 am
Debating about whether a discussion is lame or not? Lame.

Let's get back on topic.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: meekGee on 01/06/2017 06:12 am
SpaceX is doing with Dragon what they did with Falcon.

Starting out with a simple vehicle that works and provides a service they can bill for while learning the ropes.

Then following a path where they evolve the vehicle until it becomes revolutionary, while still making money.

This approach allowed them to do a huge amount of development, quickly, and cheaply.

This has rattled the industry, which is not used to such fast motion.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: dglow on 01/06/2017 07:30 am
...

This approach allowed them to do a huge amount of development, quickly, and cheaply.

This has rattled the industry, which is not used to such fast motion.

It's an incredible ramp on their part. From parachutes to Mars EDL in seven years (!) is stunning. Red Dragon puts SpaceX up with the best at JPL, breathing some truly rarified air.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: AncientU on 01/06/2017 11:02 am
...

This approach allowed them to do a huge amount of development, quickly, and cheaply.

This has rattled the industry, which is not used to such fast motion.

It's an incredible ramp on their part. From parachutes to Mars EDL in seven years (!) is stunning. Red Dragon puts SpaceX up with the best at JPL, breathing some truly rarified air.

Agree -- after Red Dragon is safely on the surface. 
Many have designed for Mars EDL, but success has been quite limited.
JPL is unequaled as the standard bearer.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: AndOchoa on 01/06/2017 11:27 am

.... From parachutes to Mars EDL in seven years (!) is stunning. Red Dragon puts SpaceX up with the best at JPL, ....

I'm pro Spx, but dont forget that the CCSC SAA establishes NASA
support Spacex with six Technical Exchange Documents(TEDs):
"TED1. Deep space communications, data relay, and tracking.
TED2. Deep space trajectory design and navigation support.
TED3. Entry, descent, and landing(EDL) system engineering and analysis.
TED4. Aerosciences activities.
TED5. Flight system technical review and advice.
TED6. Planetary protection consultation and advice."

So Red Dragon will be guided by Nasa's eyes from LEO to just about to Mars EDL.
And thereafter will use NASA comms to relay its status from mars surface.
So Spx will be learning from JPL.
Best Regards, Andres.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: LouScheffer on 01/06/2017 02:34 pm

I'm pro Spx, but dont forget that the CCSC SAA establishes NASA
support Spacex with six Technical Exchange Documents(TEDs):
"TED1. Deep space communications, data relay, and tracking.
TED2. Deep space trajectory design and navigation support.
TED3. Entry, descent, and landing(EDL) system engineering and analysis.
TED4. Aerosciences activities.
TED5. Flight system technical review and advice.
TED6. Planetary protection consultation and advice."

So Red Dragon will be guided by Nasa's eyes from LEO to just about to Mars EDL.
And thereafter will use NASA comms to relay its status from mars surface.
So Spx will be learning from JPL.
Best Regards, Andres.
There is no doubt that JPL is world's-best competent at deep space.  There is also no doubt that they are expensive, and quite conservative at engineering.

So I think this division of labor makes sense.  For SpaceX to duplicate DSN and navigation functionality would be expensive, time consuming, and not their expertise or passion.  So work with NASA on these, take advantage of what they already know about Mars landings, and try the experiments that JPL probably would not.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: meekGee on 01/06/2017 02:51 pm

.... From parachutes to Mars EDL in seven years (!) is stunning. Red Dragon puts SpaceX up with the best at JPL, ....

I'm pro Spx, but dont forget that the CCSC SAA establishes NASA
support Spacex with six Technical Exchange Documents(TEDs):
"TED1. Deep space communications, data relay, and tracking.
TED2. Deep space trajectory design and navigation support.
TED3. Entry, descent, and landing(EDL) system engineering and analysis.
TED4. Aerosciences activities.
TED5. Flight system technical review and advice.
TED6. Planetary protection consultation and advice."

So Red Dragon will be guided by Nasa's eyes from LEO to just about to Mars EDL.
And thereafter will use NASA comms to relay its status from mars surface.
So Spx will be learning from JPL.
Best Regards, Andres.
I can think of no better student to learn from JPL...

Few have attempted Mars EDL, and much fewer succeeded...

SpaceX will try it in a different way and at a different scale.

Without help from JPL, their odds of succeeding would have been dismal. With JPL, even 50-50 is generous.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: DOCinCT on 01/06/2017 04:19 pm
Few have attempted Mars EDL, and much fewer succeeded...
Actually if you mean a rover or stationary lander that lasted at least as long as the warranty (that's a NASA phrase) only the USA has succeeded: 3 landers, 4 rovers; Mar3 (USSR) landed before Viking but only returned 20 seconds of data.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: meekGee on 01/06/2017 04:23 pm
Few have attempted Mars EDL, and much fewer succeeded...
Actually if you mean a rover or stationary lander that lasted at least as long as the warranty (that's a NASA phrase) only the USA has succeeded: 3 landers, 4 rovers; Mar3 (USSR) landed before Viking but only returned 20 seconds of data.
Yup. I remembered there was one other, but didn't remember how briefly it lasted.

I'm hoping that with size it'll actually get easier.

Propulsive EDL gives you more authority, and having more mass on the surface means you can brute force things, have more power etc.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: ChrisC on 01/06/2017 07:07 pm
I'm starting to wonder if we should split this thread into an Updates thread and a Discussion thread.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Oersted on 01/06/2017 09:19 pm
There is no doubt that JPL is world's-best competent at deep space.  There is also no doubt that they are expensive, and quite conservative at engineering.

Airbag and sky-crane landings isn't conservative engineering by a long stretch.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: LouScheffer on 01/06/2017 09:26 pm
There is no doubt that JPL is world's-best competent at deep space.  There is also no doubt that they are expensive, and quite conservative at engineering.
Airbag and sky-crane landings isn't conservative engineering by a long stretch.
It's not conservative on an absolute scale, but it was the most conservative option possible thart could perform the mission.  JPL will only try stuff like this when absolutely everything else has been ruled out.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: yg1968 on 01/10/2017 12:54 am
This hasn't been mentioned before. But since SNC is building two cargo DCs and Boeing is building two orbital CST-100, I am guessing that SpaceX will also build two cargo Dragon2 and two crewed Dragons2.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Dalhousie on 01/10/2017 01:27 am
There is no doubt that JPL is world's-best competent at deep space.  There is also no doubt that they are expensive, and quite conservative at engineering.
Airbag and sky-crane landings isn't conservative engineering by a long stretch.
It's not conservative on an absolute scale, but it was the most conservative option possible thart could perform the mission.  JPL will only try stuff like this when absolutely everything else has been ruled out.

Do you a source that shows the alternatives and why they were rejected?
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: gongora on 01/10/2017 02:38 am
This hasn't been mentioned before. But since SNC is building two cargo DCs and Boeing is building two orbital CST-100, I am guessing that SpaceX will also build two cargo Dragon2 and two crewed Dragons2.

SNC and Boeing are also landing on land from the beginning, and they both count on reusing those two vehicles for the entire contract.  We don't yet know how easily SpaceX will be able to reuse parts from the initial Crew Dragons that land in the water.  This is something to keep in mind when you think about the pricing of the post-certification missions.  Most people seem to assume that the SpaceX prices must be a lot cheaper per mission on the crew contract, but it may be closer than you think if SpaceX is pricing theirs based on building more vehicles or having higher refurbishment costs.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Robotbeat on 01/10/2017 02:44 am
This hasn't been mentioned before. But since SNC is building two cargo DCs and Boeing is building two orbital CST-100, I am guessing that SpaceX will also build two cargo Dragon2 and two crewed Dragons2.

SNC and Boeing are also landing on land from the beginning, and they both count on reusing those two vehicles for the entire contract.  We don't yet know how easily SpaceX will be able to reuse parts from the initial Crew Dragons that land in the water.  This is something to keep in mind when you think about the pricing of the post-certification missions.  Most people seem to assume that the SpaceX prices must be a lot cheaper per mission on the crew contract, but it may be closer than you think if SpaceX is pricing theirs based on building more vehicles or having higher refurbishment costs.
We know more about how easily Dragon will be to reuse than we do about DC and Starliner. We don't know how easily either of those two vehicles will be to reuse because they've never flown under power, let alone all the way to orbit and back. Dragon 1 has, and parts have already been reused. Full capsule reuse will occur within a few months from now.

(Additionally, the launch vehicle for SpaceX is already much cheaper and has been recovered many times and will have been reused several times before first crewed flight... The rocket is about half the price of each flight for SpaceX, so even if the others somehow had zero refurb costs, SpaceX could still potentially end up cheaper.)
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: yg1968 on 01/10/2017 03:12 am
This hasn't been mentioned before. But since SNC is building two cargo DCs and Boeing is building two orbital CST-100, I am guessing that SpaceX will also build two cargo Dragon2 and two crewed Dragons2.

SNC and Boeing are also landing on land from the beginning, and they both count on reusing those two vehicles for the entire contract.  We don't yet know how easily SpaceX will be able to reuse parts from the initial Crew Dragons that land in the water.  This is something to keep in mind when you think about the pricing of the post-certification missions.  Most people seem to assume that the SpaceX prices must be a lot cheaper per mission on the crew contract, but it may be closer than you think if SpaceX is pricing theirs based on building more vehicles or having higher refurbishment costs.

SpaceX's CCtCap contract is for $2.6B including the 6 post-certification missions.

Boeing's CCtCap contract is for 4.2B$.

SNC's CCtCap contract would have been for $3.3B.

For CRS2, we only know the value of Orbital ATK's contract. It is between $1.2 and $1.5 billion.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: gongora on 01/10/2017 03:15 am
This hasn't been mentioned before. But since SNC is building two cargo DCs and Boeing is building two orbital CST-100, I am guessing that SpaceX will also build two cargo Dragon2 and two crewed Dragons2.

SNC and Boeing are also landing on land from the beginning, and they both count on reusing those two vehicles for the entire contract.  We don't yet know how easily SpaceX will be able to reuse parts from the initial Crew Dragons that land in the water.  This is something to keep in mind when you think about the pricing of the post-certification missions.  Most people seem to assume that the SpaceX prices must be a lot cheaper per mission on the crew contract, but it may be closer than you think if SpaceX is pricing theirs based on building more vehicles or having higher refurbishment costs.
We know more about how easily Dragon will be to reuse than we do about DC and Starliner. We don't know how easily either of those two vehicles will be to reuse because they've never flown under power, let alone all the way to orbit and back. Dragon 1 has, and parts have already been reused. Full capsule reuse will occur within a few months from now.

(Additionally, the launch vehicle for SpaceX is already much cheaper and has been recovered many times and will have been reused several times before first crewed flight... The rocket is about half the price of each flight for SpaceX, so even if the others somehow had zero refurb costs, SpaceX could still potentially end up cheaper.)

We really don't know much about Dragon reuse, and we don't know what sort of refurbishment Dragon 2 will need after landing in salt water (what will happen to the Super Dracos?).  The "full capsule reuse" of Dragon in a few months is a fairly extensive refurbishment that replaces the entire TPS (and we don't know what else is getting replaced).  We also don't know anything about future NASA use of refurbished boosters, do we?  The contracts are most likely for new boosters.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Robotbeat on 01/10/2017 03:43 am
Let me be clear: More is known about Dragon reuse than DC or Starliner reuse.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: woods170 on 01/10/2017 07:26 am
Let me be clear: More is known about Dragon reuse than DC or Starliner reuse.
Bold statement. In fact, there is very little known about Dragon reuse other than powerpoint statements and the occasional tidbit coming from Gwynne/Elon/other SpaceX personnel. The situation for DC and Starliner is not much different.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: dglow on 01/10/2017 07:51 am
Let me be clear: More is known about Dragon reuse than DC or Starliner reuse.
Bold statement. In fact, there is very little known about Dragon reuse other than powerpoint statements and the occasional tidbit coming from Gwynne/Elon/other SpaceX personnel. The situation for DC and Starliner is not much different.

How many DreamChasers have returned from orbit? How many Starliners?
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: woods170 on 01/10/2017 08:35 am
Let me be clear: More is known about Dragon reuse than DC or Starliner reuse.
Bold statement. In fact, there is very little known about Dragon reuse other than powerpoint statements and the occasional tidbit coming from Gwynne/Elon/other SpaceX personnel. The situation for DC and Starliner is not much different.

How many DreamChasers have returned from orbit? How many Starliners?
How many Crew Dragons (aka Dragon 2) have returned from orbit? (Notice the subject of this thread)
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: DanielW on 01/10/2017 12:35 pm
Let me be clear: More is known about Dragon reuse than DC or Starliner reuse.
Bold statement. In fact, there is very little known about Dragon reuse other than powerpoint statements and the occasional tidbit coming from Gwynne/Elon/other SpaceX personnel. The situation for DC and Starliner is not much different.

How many DreamChasers have returned from orbit? How many Starliners?
How many Crew Dragons (aka Dragon 2) have returned from orbit? (Notice the subject of this thread)

I think the point is some component / process data vs basically no data. Some, no matter how small, is always greater than none.
Dracos have flown and dunked in the ocean. PicaX, Various tank and hull materials, and common fillers, welds and sealants. Many parts will be new and present unknowns, but for others the risk is already retired. I make no claims as to how big an advantage that is, but it is worth something. Boeing will have similar, if not greater, experience to draw on with materials and processes but the parts and assemblies are all new.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: gongora on 01/10/2017 02:33 pm
I think the point is some component / process data vs basically no data. Some, no matter how small, is always greater than none.
Dracos have flown and dunked in the ocean. PicaX, Various tank and hull materials, and common fillers, welds and sealants. Many parts will be new and present unknowns, but for others the risk is already retired. I make no claims as to how big an advantage that is, but it is worth something. Boeing will have similar, if not greater, experience to draw on with materials and processes but the parts and assemblies are all new.

For Dracos and PicaX that have flown and been dunked in the ocean, is any of that going to be reused?  This line of reasoning seems to be that since SpaceX has dunked a capsule in the ocean then SNC and Boeing will have higher refurbishment costs, and I'm really not following that.  The SNC and Boeing performance is certainly unknown right now, but their project plans rely on early and nearly complete reuse in a way that the SpaceX contracts may not (all of them will need to replace the parts they dump on return to Earth of course, which is significant on the Boeing vehicle).
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: dglow on 01/10/2017 04:56 pm

How many DreamChasers have returned from orbit? How many Starliners?
How many Crew Dragons (aka Dragon 2) have returned from orbit? (Notice the subject of this thread)

Look, I respect you on this forum – but c'mon, a response like that reads as slippery. Is my point invalid because of the thread title, or because no commonality (and thus transference of recovery experience) exists between Dragons 1 and 2? I would challenge either of those!  ;)

This line of reasoning seems to be that since SpaceX has dunked a capsule in the ocean then SNC and Boeing will have higher refurbishment costs, and I'm really not following that.

You're right, it doesn't follow. Is that your line of reasoning? Because I don't recall where that was stated.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: joek on 01/10/2017 05:42 pm
SpaceX's CCtCap contract is for $2.6B including the 6 post-certification missions.

We also know ~$1.1B of that is for the SpaceX base CCtCap contract exclusive of the non-guaranteed PCM's, based on Feb-2015 Congressional testimony--granted not including subsequent contract revisions, which are impossible to cipher based on subsequent public information.  I believe there is also a strong hint in same as to Boeing's base-vs-recurring mission price (IIRC posted it way-back-when), but I cannot find it at the moment. Sorry don't have a link handy.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: woods170 on 01/10/2017 06:08 pm

How many DreamChasers have returned from orbit? How many Starliners?
How many Crew Dragons (aka Dragon 2) have returned from orbit? (Notice the subject of this thread)

Look, I respect you on this forum – but c'mon, a response like that reads as slippery. Is my point invalid because of the thread title, or because no commonality (and thus transference of recovery experience) exists between Dragons 1 and 2? I would challenge either of those!  ;)
My point is: any knowledge on re-use of Dragon has not (yet) actually passed the reality check. Right now SpaceX has a lot of recovered once-used Cargo Dragons to play around with, but their knowledge about Dragon reuse is just as hypothetical as knowledge about Starliner and/or DC reuse. No Dragon (cargo or crew) has been reused at this time. It is not until SpaceX succesfully recovers a reused Dragon, and start learning from it, that their knowledge base on reuse will increase significantly beyond those of Starliner and/or DC.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: rockets4life97 on 01/10/2017 06:19 pm
The implication I heard when Benji from discussed dragon re-use was that SpaceX has been re-using parts of Dragon 1 building up to the re-use of the pressure vessel. So, NASA is confident in however much re-use is happening on CRS-11. I think that is much farther along than Boeing or SNC.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: baldusi on 01/10/2017 06:52 pm
Let me be clear: More is known about Dragon reuse than DC or Starliner reuse.
Bold statement. In fact, there is very little known about Dragon reuse other than powerpoint statements and the occasional tidbit coming from Gwynne/Elon/other SpaceX personnel. The situation for DC and Starliner is not much different.

How many DreamChasers have returned from orbit? How many Starliners?
How many Crew Dragons (aka Dragon 2) have returned from orbit? (Notice the subject of this thread)
While not Crew Dragon, CRS-11 is supposed to flight a reused Dragon 1. And that will be splashed on the ocean, too. So, they already have the process to re-certify a used Dragon 1 for flight, and that's a lot more data and certainty than all of CST-100 and DC paperwork.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Chris Bergin on 01/10/2017 09:45 pm
Gentlemen, please! Let's all put our focus hats on and be excellent to each other ;D
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: wardy89 on 01/10/2017 10:41 pm
The way i see it is that while crew Dragon isn't exactly the same as Dragon 1 it is similar enough that SpaceX should have a fairly good idea of what condition it is likely to be in when it returns. They will also have been able to draw from the experience of Dragon 1 and make improvements in the design of crew Dragon to aid reuse. 

As for the CST-100 and Dream Chaser while i am sure they have a good idea of what they expect will be needed refurbishment wise, as nether vehicle has flown in any form there will always be question marks until they get the first couple of vehicles back after a reentry and inspect them to see.

However this can also be said for SpaceX, as while crew Dragon is derived from the Dragon 1 it is different enough that it could throw up a phew surprises.

For now i suspect we are not going to learn much about the reuse of the vehicles until they start flying and even then i suspect we won't learn huge amounts.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: joek on 01/10/2017 10:55 pm
My point is: any knowledge on re-use of Dragon has not (yet) actually passed the reality check. Right now SpaceX has a lot of recovered once-used Cargo Dragons to play around with, but their knowledge about Dragon reuse is just as hypothetical as knowledge about Starliner and/or DC reuse. No Dragon (cargo or crew) has been reused at this time. It is not until SpaceX succesfully recovers a reused Dragon, and start learning from it, that their knowledge base on reuse will increase significantly beyond those of Starliner and/or DC.

Given that they have actual used articles to examine, your assertion that "their knowledge about Dragon reuse is just as hypothetical as knowledge about Starliner and/or DC reuse" is BS not completely correct.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: yg1968 on 01/11/2017 03:35 am
SpaceX's CCtCap contract is for $2.6B including the 6 post-certification missions.

We also know ~$1.1B of that is for the SpaceX base CCtCap contract exclusive of the non-guaranteed PCM's, based on Feb-2015 Congressional testimony--granted not including subsequent contract revisions, which are impossible to cipher based on subsequent public information.  I believe there is also a strong hint in same as to Boeing's base-vs-recurring mission price (IIRC posted it way-back-when), but I cannot find it at the moment. Sorry don't have a link handy.

I think that I found it in Gerst's Statement from that February 2015 hearing:

https://science.house.gov/legislation/hearings/subcommittee-space-hearing-commercial-crew-program-challenges-and-opportunities

Quote from: Statement by Gerst
It is not possible to do a direct price comparison between Soyuz and Commercial Crew for crew transportation. Soyuz is purchased by the “crew seat” while Commercial Crew flights are purchased on a per mission basis which includes four seats and an additional 100kg of pressurized cargo. However, an equivalent seat price can be calculated for Commercial Crew using the prices established in the CCtCap contracts for the 4-seat configuration and excluding the price for the additional cargo. Using the pricing in the CCtCap contracts for the 12 Post Certification Missions (6 per company) and assuming all 12 missions are purchased and flown at a rate of two per year, the average seat price is $58 million per seat for Commercial Crew. The currently contracted seat price for Soyuz for 2017 is approximately $76 million per seat. Soyuz seat pricing has been increasing at a rate of approximately 9 percent per year.

https://science.house.gov/sites/republicans.science.house.gov/files/documents/HHRG-114-SY16-WState-BGerstenmaier-20150227.PDF
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: yg1968 on 01/11/2017 03:45 am
From these numbers, you then get to $1.1B for SpaceX's 6 post-certification missions (excluding cargo) by adding $58M x 12 missions x 4 seats x $2.6B/$6.8B = $1.1B. So for SpaceX you would get a price of approximately $46M per seat ($1.1B /6 missions / 4 seats =$44M). An easier way to get to that price per seat number is through this equation: $58M x 2 seats (one for each of the providers) x $2.6B/$6.8B=$44M.

For Boeing, you would get $1.7B for six post-certification missions ($58M x 12 missions x 4 seats x $4.2B/$6.8B = $1.7B). You would then divide that $1.7B by 6 missions and by 4 seats which gives you approximately $72M per seat. An easier way to get to that price per seat number is through this equation: $58M x 2 seats x $4.2B/$6.8B=$72M.

P.S. These numbers assume that the ratio of the price of the post-certifications missions (without cargo) over the total value of the CCtCap contract is similar for both SpaceX and Boeing. This may not be the case. 
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: LouScheffer on 01/11/2017 05:28 pm
There is no doubt that JPL is world's-best competent at deep space.  There is also no doubt that they are expensive, and quite conservative at engineering.
Airbag and sky-crane landings isn't conservative engineering by a long stretch.
It's not conservative on an absolute scale, but it was the most conservative option possible thart could perform the mission.  JPL will only try stuff like this when absolutely everything else has been ruled out.
Do you a source that shows the alternatives and why they were rejected?
One place to look is Chapter 8, "The Least Unacceptable Solution" of the book, "The Right Kind of Crazy".  They  went through a bunch of alternatives.  Airbags did not scale well to the needed size, despite a lot of effort.  Rocket, then legs, were too tippy for uncertain terrain.  A crushable platform was too heavy, and a badly placed rock could still kill it.  A rocket with the rover hanging below during descent was too pendulum-y.  And so on, till they got to the sky-crane.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: joek on 01/11/2017 07:28 pm
I think that I found it in Gerst's Statement from that February 2015 hearing:
...
Thanks.  That was it (glad to know I was not imagining)!

p.s. Trying to catch up on what's been happening recently as have been buried in other work.  After a 6+ month hiatus, I'm a bit disappointed in CCtCap progress.  Oh well.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: woods170 on 01/12/2017 06:34 am
I think that I found it in Gerst's Statement from that February 2015 hearing:
...
Thanks.  That was it (glad to know I was not imagining)!

p.s. Trying to catch up on what's been happening recently as have been buried in other work.  After a 6+ month hiatus, I'm a bit disappointed in CCtCap progress.  Oh well.
Most progress is currently being made on systems that go inside the spacecraft (avionics, ECLSS, propulsion, etc.etc.) That kind of work generally has a tendency NOT to result in news-worthy pictures and press releases. Also, since the start of CCtCAP SpaceX has very much clammed-up on CCP. The number of images and the amount of news they release has significantly decreased since CCiCAP. The reason is obvious: they are now deep into the proprietary hardware phase. Also, Elon has decided to postpone the revealing of the spacesuit until after it has been qualified for use on Dragon 2. And that is partially dependent on qualification of Dragon 2 ECLSS (which is still in-work). Boeing's spacesuit on the other hand is one we are all familiar with: Modified ACES (MACES). Basically a modified version of what was worn by shuttle astronauts on ascent and descent.
Given that Boeing has more involvement of public facilities (RCS testing at White Sands for example) and entities (NASA MOD for mission control for example) they have a somewhat greater stream of images and news going out to the public.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: DOCinCT on 01/12/2017 12:39 pm
There are tidbits online on SpaceX progress re: Commercial Crew.
For instance, NASA posted this on their 2016 progress slide show:
"The company also ran a series of qualification tests on the spacesuits astronauts will wear during missions aboard Crew Dragon spacecraft. The evaluation included putting the suit in a vacuum chamber to see how it withstood conditions similar to those found in space outside a spacecraft."
What we don't know is how well it performed.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Robotbeat on 01/12/2017 12:44 pm
There are tidbits online on SpaceX progress re: Commercial Crew.
For instance, NASA posted this on their 2016 progress slide show:
"The company also ran a series of qualification tests on the spacesuits astronauts will wear during missions aboard Crew Dragon spacecraft. The evaluation included putting the suit in a vacuum chamber to see how it withstood conditions similar to those found in space outside a spacecraft."
...
(emphasis mine)

This is interesting because it isn't a commercial crew requirement. Pressure suits used for ascent are not used for EVAs nowadays, they're just for safety.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: clongton on 01/12/2017 04:40 pm
There are tidbits online on SpaceX progress re: Commercial Crew.
For instance, NASA posted this on their 2016 progress slide show:
"The company also ran a series of qualification tests on the spacesuits astronauts will wear during missions aboard Crew Dragon spacecraft. The evaluation included putting the suit in a vacuum chamber to see how it withstood conditions similar to those found in space outside a spacecraft."
...
(emphasis mine)

This is interesting because it isn't a commercial crew requirement. Pressure suits used for ascent are not used for EVAs nowadays, they're just for safety.

I would assume that they are just exploring the limits. That's what they did with the Falcon; "fly it till it breaks".
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Jim on 01/12/2017 05:05 pm
There are tidbits online on SpaceX progress re: Commercial Crew.
For instance, NASA posted this on their 2016 progress slide show:
"The company also ran a series of qualification tests on the spacesuits astronauts will wear during missions aboard Crew Dragon spacecraft. The evaluation included putting the suit in a vacuum chamber to see how it withstood conditions similar to those found in space outside a spacecraft."
...
(emphasis mine)

This is interesting because it isn't a commercial crew requirement. Pressure suits used for ascent are not used for EVAs nowadays, they're just for safety.

Reading too much into it.  I would only say that means just vacuum and not heat or cold.  An environmental chamber provides vacuum, heat, cold, sunlit, etc.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: CorvusCorax on 01/12/2017 06:43 pm
Well, if the Dragon2 would depressurise while on approach to the space station (meteorite strike or similar), you might have to evacuate the vehicle. I'm not 100% familiar with the docking architecture through the mating adapters but afair those do not include a real airlock that could be cycled in order to enter or leave from a depressurized vehicle to the pressurized space station or the other way around.

So if Dragon2 can for whatever reason not be repressurized, they might have to EVA (likely with the help of station crew in real EVA suits) to get to one of the stations main airlocks, Quest or Poisk.

The only other option i see is to make an unpressurized reentry, but any damage to Dragon that compromises the pressure vessel could also easily damage the heat shield, barring that option.

Edit: That, or depressurize parts of the station and misuse them as an airlock like the Russians did to Zvesda in the stations early days. But that only works if the docking mechanism still works. There's scenarios thinkable where Dragon2 gets damaged and a docking manouver is no longer possible (other than debris strike, I could think of a hatch malfunction, or a collission with the station itself on docking approach. Unlikely, but its good to have a contingency plan)
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: obi-wan on 01/12/2017 07:27 pm
There is no contractual requirement for either commercial crew vehicle to support EVA, even for contingency purposes. Launch and escape suits are built for keeping the person alive following depressurization long enough to get home: the only required mobility is that sufficient to work controls while in your seat. They are also used for escape in the presence of fire or toxic chemicals, but in that case they operate at "vent pressure" just sufficient to keep outside air outside (they're a lot more mobile like this than if pressurized.) That's all that the shuttle ACES suit was capable of; there was some development of a modified ACES for the ARM mission to support EVA, but it was pretty unwieldy, and the last plans I saw included carrying EMUs for the EVA ops. I don't know if "modified ACES" for Boeing is an outgrowth of the EVA ACES development, or just an upgraded ACES from Sshuttle days strictly for launch and entry; I suspect the latter.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Robotbeat on 01/12/2017 09:03 pm
There are tidbits online on SpaceX progress re: Commercial Crew.
For instance, NASA posted this on their 2016 progress slide show:
"The company also ran a series of qualification tests on the spacesuits astronauts will wear during missions aboard Crew Dragon spacecraft. The evaluation included putting the suit in a vacuum chamber to see how it withstood conditions similar to those found in space outside a spacecraft."
...
(emphasis mine)

This is interesting because it isn't a commercial crew requirement. Pressure suits used for ascent are not used for EVAs nowadays, they're just for safety.

Reading too much into it.  I would only say that means just vacuum and not heat or cold.  An environmental chamber provides vacuum, heat, cold, sunlit, etc.
Probably right it was just vacuum, but it is worded strangely if EVA isn't an eventual goal.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: sdsds on 01/12/2017 11:40 pm
Probably right it was just vacuum, but it is worded strangely if EVA isn't an eventual goal.

It's really difficult to evaluate the wording out of context. Was there any hint at contingency (i.e. emergency) EVA? What is possible for rescue of the crew of a totally disabled visiting vehicle? What if its orbit were within reach of a docked Soyuz? The Soyuz orbital module is an airlock....
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Doesitfloat on 01/13/2017 01:29 pm
How much of an Eva could Astronuts do in the orange Shuttle Suits, or in the Soyuz suits?
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Robotbeat on 01/13/2017 01:33 pm
I don't think the orange shuttle suits could work at all in vacuum as they were rated to just 100,000ft. But I'd like to be corrected or confirmed on that.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: dglow on 01/13/2017 01:34 pm
How much of an Eva could Astronuts do in the orange Shuttle Suits, or in the Soyuz suits?

Exactly none.

Orange shuttle suits: https://en.wikipedia.org/wiki/Advanced_Crew_Escape_Suit
Soyuz suits: https://en.wikipedia.org/wiki/Sokol_space_suit
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: RonM on 01/13/2017 02:36 pm
How much of an Eva could Astronuts do in the orange Shuttle Suits, or in the Soyuz suits?

Exactly none.

Orange shuttle suits: https://en.wikipedia.org/wiki/Advanced_Crew_Escape_Suit
Soyuz suits: https://en.wikipedia.org/wiki/Sokol_space_suit

Yes, those are IVA suits designed to protect the crew in case of vehicle depressurization and that's all they do. An important task, but insufficient for an EVA.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Nomadd on 01/13/2017 07:44 pm
I don't think the orange shuttle suits could work at all in vacuum as they were rated to just 100,000ft. But I'd like to be corrected or confirmed on that.
100,000 feet pretty much is vacuum as far as people go. Only about .16 PSI. If a suit could handle 100,000 feet it should be able to handle an outside airlock to airlock transfer or something until the air got stale. Depends on what you call an EVA.

"what you "can* an EVA" didn't make much sense.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: acsawdey on 01/13/2017 09:08 pm
I don't think the orange shuttle suits could work at all in vacuum as they were rated to just 100,000ft. But I'd like to be corrected or confirmed on that.
100,000 feet pretty much is vacuum as far as people go. Only about .16 PSI. If a suit could handle 100,000 feet it should be able to handle an outside airlock to airlock transfer or something until the air got stale. Depends on what you can an EVA.

Could it be that those suits become so rigid under vacuum/near-vacuum that you don't really have the mobility to do an EVA?
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: SWGlassPit on 01/13/2017 09:36 pm
There's a lot more to EVA hazards than just vacuum.  Thermal management is probably going to be your biggest thorn in this case.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: yg1968 on 01/17/2017 05:24 pm
This news impacts crew Dragon2, so I am cross-posting it here also:

Ars Technica: As leadership departs, NASA quietly moves to buy more Soyuz seats (http://arstechnica.com/science/2017/01/nasa-formally-seeks-option-to-buy-additional-soyuz-seats-for-2019/)
Eric Berger wrote an article about NASA planning to buy more Soyuz seats for early 2019, as well as extra seats available in 2017 and 2018. 

He provides a link to the solicitation: PROCUREMENT OF CREW TRANSPORTATION AND RESCUE SERVICES FROM BOEING (https://www.fbo.gov/index?s=opportunity&mode=form&id=d4bd5c52373053a6dfb6acd03398978c&tab=core&_cview=0).  Apparently Boeing bought the rights to the available Soyuz seats and is going to resell them to NASA.

Here are some excerpts from the solicitation:
Quote
NASA is considering contracting with The Boeing Company (Boeing) for crew transportation services to and from the International Space Station (ISS) on the Russian Soyuz vehicle. This transportation would be for one crewmember in the Fall of 2017 and one crewmember in the Spring of 2018. NASA is considering purchasing these services from Boeing, without competition, because no other vehicles are currently capable of providing these services in Fall 2017 or Spring 2018. NASA has contracts with two U.S. commercial companies for crew transportation to the ISS. However, these vehicles are still in the developmental stage, and not expected to begin fully operational flights to the ISS until 2019. NASA also is considering an option to acquire crew transportation from Boeing for three crewmembers on the Soyuz in 2019, to ensure the availability of back-up transportation capability in the event the U.S. commercial contractor vehicles are delayed or to augment future ISS operations and research.
...
An agreement was recently reached between the Boeing Company and S.P. Korolev Rocket and Space Public Corporation, Energia ("RSC Energia"), who is the manufacturer of the Soyuz spacecraft and has the legal rights to sell the seats and associated services. As a part of this agreement, Energia agreed to provide to Boeing two specifically identified seats on the Soyuz spacecraft for long-duration travel to and from the ISS, one on a flight to occur in the Fall 2017 timeframe and another on a flight to occur in the Spring 2018 timeframe. Additionally, Energia provided Boeing three additional specifically identified seats in the Spring 2019 timeframe on two Soyuz spacecraft. Finally, Boeing and RSC Energia agreed that each of these five seats will include a launch of an individual to and from the ISS, including all services normally provided during launches to ISS. Boeing and RSC Energia have represented that Boeing has the full rights to these seats and can sell them to any third party.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: DOCinCT on 01/21/2017 12:26 pm
NASA posted 17 Commercial Crew Things to Track in 2017 1/20/2017 on their website, these are the 'take aways' for SpaceX

2. Structural Qualification: SpaceX is on pace to complete structural qualification of the Crew Dragon capsule and trunk in early 2017. The company built the Crew Dragon Qualification Vehicle to prove its design will hold up to the rigors of spaceflight.

4. Complete Manufacturing: SpaceX also will complete manufacturing of three Crew Dragons that are currently in early phases of assembly. These spacecraft will perform Demonstration Mission 1, flight test without crew, Demonstration Mission 2, flight test with a crew aboard, and the company’s first crew rotation mission.

7. Draco and SuperDraco: The Draco and SuperDraco thrusters for SpaceX's Crew Dragon are on pace to complete static-fire qualification testing in the first few months of 2017. SpaceX produces both thrusters in-house. The smaller Draco thrusters maneuver the spacecraft while it's in orbit and provide small adjustments. The SuperDracos, which are 3D printed, are much larger and produce enough thrust to lift the Crew Dragon out of danger in case of an abort situation. The company expects to complete propulsion system validation testing by demonstrating capability in all phases of flight using a dedicated module by the second half of 2017.

10.  ......Throughout 2017, both companies will subject their suits to rigorous testing in multiple circumstances that might be encountered in space. SpaceX has completed spacesuit development testing and will build the training and flight suits for its crewed demonstration flight and first crew rotation mission after astronauts are assigned to missions.

13. Launch Complex 39A: SpaceX has overhauled the historic Launch Pad 39A at Kennedy and built new support structures for the company's line of Falcon rockets. The Crew Access Arm, currently under construction, will be connected in the spring to provide a bridge from the fixed service structure to the Crew Dragon spacecraft so astronauts can board before launch. The launch pad will be put to the test when SpaceX launches its Falcon 9 from the pad in early 2017. It will mark the first flight off of Pad 39A since the final space shuttle mission in 2011.

15. Falcon 9 Production: SpaceX will build up the Falcon 9 rockets that will launch Crew Dragons into orbit for the flight tests of its systems. SpaceX builds its rockets, Merlin engines and Crew Dragon spacecraft at the company's factory and headquarters in Hawthorne, California.

16. Flight Test: SpaceX is slated to make its first flight test – without a crew – in November 2017. Flying to the space station using its automated guidance and navigation systems, the Crew Dragon will dock there on its own and remain for a time before detaching and parachuting back to Earth and landing in the Atlantic Ocean off the coast of Cape Canaveral. The mission will be a dress rehearsal for a later flight test that will include astronauts.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: DanseMacabre on 01/21/2017 12:32 pm
16. Flight Test: SpaceX is slated to make its first flight test – without a crew – in November 2017. Flying to the space station using its automated guidance and navigation systems, the Crew Dragon will dock there on its own and remain for a time before detaching and parachuting back to Earth and landing in the Atlantic Ocean off the coast of Cape Canaveral. The mission will be a dress rehearsal for a later flight test that will include astronauts.

Regarding this point, it seems to indicate that the dragon capsule will not be entered into by crew?
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: kevinof on 01/21/2017 12:37 pm
I would think they would enter and inspect it and possibly collect the "cheese" or whatever other goodies have been sent up with it. If this is the full monte then I've no doubt the crew on the ISS would love to sit in the drivers seat and play.


16. Flight Test: SpaceX is slated to make its first flight test – without a crew – in November 2017. Flying to the space station using its automated guidance and navigation systems, the Crew Dragon will dock there on its own and remain for a time before detaching and parachuting back to Earth and landing in the Atlantic Ocean off the coast of Cape Canaveral. The mission will be a dress rehearsal for a later flight test that will include astronauts.

Regarding this point, it seems to indicate that the dragon capsule will not be entered into by crew?
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Jcc on 01/21/2017 01:15 pm
NASA posted 17 Commercial Crew Things to Track in 2017 1/20/2017 on their website, these are the 'take aways' for SpaceX


4. Complete Manufacturing: SpaceX also will complete manufacturing of three Crew Dragons that are currently in early phases of assembly. These spacecraft will perform Demonstration Mission 1, flight test without crew, Demonstration Mission 2, flight test with a crew aboard, and the company’s first crew rotation mission.
.

So, 3 Dragon 2 capsules are being manufactured, or more specifically, NASA is paying for 3 to be manufactured. If they by any chance have another pressure vessel in production, it could become Red Dragon???
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: old_sellsword on 01/21/2017 01:42 pm
NASA posted 17 Commercial Crew Things to Track in 2017 1/20/2017 on their website, these are the 'take aways' for SpaceX


4. Complete Manufacturing: SpaceX also will complete manufacturing of three Crew Dragons that are currently in early phases of assembly. These spacecraft will perform Demonstration Mission 1, flight test without crew, Demonstration Mission 2, flight test with a crew aboard, and the company’s first crew rotation mission.
.

So, 3 Dragon 2 capsules are being manufactured, or more specifically, NASA is paying for 3 to be manufactured. If they by any chance have another pressure vessel in production, it could become Red Dragon???

There's actually five pressure vessels in production. (https://www.nasa.gov/specials/CCP2016/)

Quote
SpaceX has five Crew Dragon spacecraft in different levels of assembly. The company built and successfully tested one module to prove its environmental and life support systems and another as a structural test article. The three spacecraft that will fly the flight tests and the first operational mission to the space station are in various stages of production in SpaceX’s manufacturing facilities in Hawthorne, California.

They might repurpose one of the two test articles as Red Dragon if they need to, or possibly even the DM-1/Inflight Abort capsule.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: jpo234 on 01/21/2017 02:00 pm
... or possibly even the DM-1/Inflight Abort capsule.
Red Dragon launch is planned for May 2018. DM-1 is planned for November 2017. I can't see how they could launch in November, refurbish the Dragon for the in flight abort test, perform the abort test and then do the Red Dragon modifications in less than 6 months.
When does the space craft need to be ready for the May 2018 launch? March?
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: woods170 on 01/21/2017 03:35 pm
They might repurpose one of the two test articles as Red Dragon if they need to, or possibly even the DM-1/Inflight Abort capsule.
From what I'm hearing the Qual vehicle will be re-purposed into the first Red Dragon vehicle. No ECLSS and crew systems needed on Red Dragon, and the Qual vehicle does not have those either. And if the schedule holds together the Qual vehicle will be available for mods to Red Dragon sometime in summer 2017.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: llanitedave on 01/21/2017 03:50 pm
... or possibly even the DM-1/Inflight Abort capsule.
Red Dragon launch is planned for May 2018. DM-1 is planned for November 2017. I can't see how they could launch in November, refurbish the Dragon for the in flight abort test, perform the abort test and then do the Red Dragon modifications in less than 6 months.
When does the space craft need to be ready for the May 2018 launch? March?

I strongly suspect that the Sept 1 anomaly has made May of 2018 nonworkable.  I think it will be pushed back until the next window.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: old_sellsword on 01/21/2017 03:58 pm
... or possibly even the DM-1/Inflight Abort capsule.
Red Dragon launch is planned for May 2018. DM-1 is planned for November 2017. I can't see how they could launch in November, refurbish the Dragon for the in flight abort test, perform the abort test and then do the Red Dragon modifications in less than 6 months.
When does the space craft need to be ready for the May 2018 launch? March?

I strongly suspect that the Sept 1 anomaly has made May of 2018 nonworkable.  I think it will be pushed back until the next window.

How does a Falcon 9 second stage anomaly have any impact on Dragon 2/Red Dragon development and production? If what woods170 says is true about the current qual article being repurposed, then the DM-1 schedule is irrelevant.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: dglow on 01/21/2017 04:12 pm
I strongly suspect that the Sept 1 anomaly has made May of 2018 nonworkable.  I think it will be pushed back until the next window.

How does a Falcon 9 second stage anomaly have any impact on Dragon 2/Red Dragon development and production? If what woods170 says is true about the current qual article being repurposed, then the DM-1 schedule is irrelevant.

Delay in inaugural FH launch. Greater urgency to launch F9 for paying customers.  All east coast launches share a single pad until LC-40 is repaired.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: meekGee on 01/21/2017 04:15 pm
... or possibly even the DM-1/Inflight Abort capsule.
Red Dragon launch is planned for May 2018. DM-1 is planned for November 2017. I can't see how they could launch in November, refurbish the Dragon for the in flight abort test, perform the abort test and then do the Red Dragon modifications in less than 6 months.
When does the space craft need to be ready for the May 2018 launch? March?

I strongly suspect that the Sept 1 anomaly has made May of 2018 nonworkable.  I think it will be pushed back until the next window.

How does a Falcon 9 second stage anomaly have any impact on Dragon 2/Red Dragon development and production? If what woods170 says is true about the current qual article being repurposed, then the DM-1 schedule is irrelevant.
I hope this can still happen, but I share the concern - they don't have an infinite number of engineers, and that failure took up a lot of resources.

Shit happens.  As long as they execute their plans, even 4 years behind schedule, it's still decades before anything else that existed before them, so I'm happy.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: dglow on 01/21/2017 07:22 pm
Shit happens.  As long as they execute their plans, even 4 years behind schedule, it's still decades before anything else that existed before them, so I'm happy.

True, but slipping two synods would be a big letdown, both among enthusiasts and inside the company.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: meekGee on 01/21/2017 07:26 pm
Shit happens.  As long as they execute their plans, even 4 years behind schedule, it's still decades before anything else that existed before them, so I'm happy.

True, but slipping two synods would be a big letdown, both among enthusiasts and inside the company.
Yes, but always compare to alternatives.

When Amos 6 happens, I was all like "damn, that's a two year delay on the way to Mars".  I am now holding hope that maybe it isn't.

But still, when Musk showed the Mars plans less than a year ago, it was a shift to the left of probably 10 years, compared to what I was willing to hope for as a new case.

So as long as it's just a time delay, honestly, it's still too awesome.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Jcc on 01/21/2017 07:31 pm
One of the major developments that need to be done for RD is the deep space qualified avionics and comms which is not needed for CRS or Crew, so not NASA milestones. However, I think NASA is providing some advice on it under the Space Act agreement.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: dglow on 01/21/2017 08:03 pm
Shit happens.  As long as they execute their plans, even 4 years behind schedule, it's still decades before anything else that existed before them, so I'm happy.

True, but slipping two synods would be a big letdown, both among enthusiasts and inside the company.
Yes, but always compare to alternatives.
C'mon, we all know there aren't any.  ::)

Quote
But still, when Musk showed the Mars plans less than a year ago, it was a shift to the left of probably 10 years, compared to what I was willing to hope for as a new case.

So as long as it's just a time delay, honestly, it's still too awesome.

Still awesome, definitely. Musk announcing Red Dragon and wishful timelines isn't enough, by itself, to set expectations. But then word gets out that NASA is engaged and excited about RD, and that begins to draw a line in the sand.

Now consider the ambitious dates Musk drops this past September. The line becomes a more firm hope/expectation because, as the first of many lines, any slip in it implies a slip to those which follow.

Red Dragon in 2020 will be fine, but 2022...  :'(
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Robotbeat on 01/21/2017 08:12 pm
They could still launch in June, by the way. They can slip to later in the window if they compromise some things, like a different landing site (lower altitude and/or closer to the equator), longer transit, expend the center core, lower payload, or make a more aggressive landing burn.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Jcc on 01/21/2017 08:30 pm
One of the major developments that need to be done for RD is the deep space qualified avionics and comms which is not needed for CRS or Crew, so not NASA milestones. However, I think NASA is providing some advice on it under the Space Act agreement.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: meekGee on 01/21/2017 08:34 pm
That's the point... People should stop whining.  Amazing how quickly we go from "omg this is Sci Fi come true in our lifetimes" to "boo hoo time-dilation why is my Pizza late".

https://www.youtube.com/watch?v=q8LaT5Iiwo4

"Give it a minute!  It's going to SPACE!"

Shit happens.  As long as they execute their plans, even 4 years behind schedule, it's still decades before anything else that existed before them, so I'm happy.

True, but slipping two synods would be a big letdown, both among enthusiasts and inside the company.
Yes, but always compare to alternatives.
C'mon, we all know there aren't any.  ::)

Quote
But still, when Musk showed the Mars plans less than a year ago, it was a shift to the left of probably 10 years, compared to what I was willing to hope for as a new case.

So as long as it's just a time delay, honestly, it's still too awesome.

Still awesome, definitely. Musk announcing Red Dragon and wishful timelines isn't enough, by itself, to set expectations. But then word gets out that NASA is engaged and excited about RD, and that begins to draw a line in the sand.

Now consider the ambitious dates Musk drops this past September. The line becomes a more firm hope/expectation because, as the first of many lines, any slip in it implies a slip to those which follow.

Red Dragon in 2020 will be fine, but 2022...  :'(
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: dglow on 01/21/2017 08:47 pm
You aren't wrong. And I'm more than willing to admit susceptibility to time-dialation... in fact, I think it's a kind of survival strategy in this day and age we occupy.

Yes, it's all relative, and yes it's Musk's fault. Very simply: when you announce a 42-engine beast and drop timeframes like '2026', then suddenly a capsule on Mars becomes small change and four years becomes an eternity.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Robotbeat on 01/21/2017 08:53 pm
Just as an aside and not really directed to anyone:
Musk's timelines are always "no earlier than." Meaning "we think it's possible to do it by 2026." Like, physically possible. It's not a prediction of when it WILL happen and /CERTAINLY/ isn't a guarantee.

Musk pushes himself to meet these goals anyway. But it's  /factually incorrect/  to claim that it's a prediction that Musk keeps failing to live up to.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: guckyfan on 01/21/2017 09:06 pm
One of the major developments that need to be done for RD is the deep space qualified avionics and comms which is not needed for CRS or Crew, so not NASA milestones. However, I think NASA is providing some advice on it under the Space Act agreement.

I am not worried about the avionics. An avionics set that NASA accepts for 6 month in LEO for a manned vehicle should stand up for 6 month in deep space when it does not need to meet man rated standards.

Deep space comm is something else but you say NASA may offer help there.

BTW ITS to Mars in 2026? Have I missed something? The date given for first crewed flight is 2024. Of course we all expect it to slip.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: dglow on 01/21/2017 09:13 pm
Musk's timelines are always "no earlier than." Meaning "we think it's possible to do it by 2026." Like, physically possible. It's not a prediction of when it WILL happen and /CERTAINLY/ isn't a guarantee.

Musk pushes himself to meet these goals anyway. But it's  /factually incorrect/  to claim that it's a prediction that Musk keeps failing to live up to.

Of course! This isn't about holding Musk's feet to the fire – not at all. It's about recognizing that when one declares "ALL THIS – possible in ten years", that such a statement necessarily resets our expectations, regardless of conditionals. As well it should.

This, I believe, is Musk's intent. And it's a Good Thing™.

He wants Mars to appear attainable, to break the "next 20 25 30 years" bubble. And many have written of the benefits for plans which can be executed within the purview of a single presidential administration (to whatever extent that would impact public funding, in this case).
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: cro-magnon gramps on 01/21/2017 09:35 pm
All I want is to get a direct answer.. not to start a war...

Is there there a technical reason why a Red Dragon has
to be launched at the "optimal" time in a synod,
and not say 5-6 months lor a year later...

I'm not worried about mass delivered to the surface of Mars...
just a purely technical "it can't happen" no matter how much
money you put into it...

Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Robotbeat on 01/21/2017 09:50 pm
A year is too much unless you pick a much more energetic trajectory, like a Venus flyby or something. Probably wouldn't work for RD on FH.

...but you can probably launch at basically any time if you're willing to wait like years for the payload to arrive.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: brickmack on 01/21/2017 10:14 pm
All I want is to get a direct answer.. not to start a war...

Is there there a technical reason why a Red Dragon has
to be launched at the "optimal" time in a synod,
and not say 5-6 months lor a year later...

I'm not worried about mass delivered to the surface of Mars...
just a purely technical "it can't happen" no matter how much
money you put into it...

It can't happen, the energy needed to send a payload to Mars massively increases outside the launch window (even just a couple weeks can add several km/s). Even for a rocket as large as FH, the energy needs quickly become so great that the payload capacity is negative (can't even send an empty upper stage). Look up "porkchop plots"
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: cro-magnon gramps on 01/22/2017 12:29 am
All I want is to get a direct answer.. not to start a war...

Is there there a technical reason why a Red Dragon has
to be launched at the "optimal" time in a synod,
and not say 5-6 months lor a year later...

I'm not worried about mass delivered to the surface of Mars...
just a purely technical "it can't happen" no matter how much
money you put into it...

It can't happen, the energy needed to send a payload to Mars massively increases outside the launch window (even just a couple weeks can add several km/s). Even for a rocket as large as FH, the energy needs quickly become so great that the payload capacity is negative (can't even send an empty upper stage). Look up "porkchop plots"

What I am getting from this, (I left this type of math 50 years ago) that regardless of the size of the payload decrease, the drop off is so quick that it makes no sense to send a space craft of any configuration outside the synod window... is that right...

btw I am more or less asking this for the common man or woman who might run across this thread...

edit http://mars.jpl.nasa.gov/spotlight/porkchopAll.html a simplified tech description of Pork Chop Plots
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: meekGee on 01/22/2017 02:03 am
I wrote a simulator some years ago, and what I found was that for realistic deltaV, it wasn't really matter of mass...

You could send a payload to Mars early, but it wouldn't get there much sooner.  you could just wait on earth (which is catching up), launch on time, and get to Mars at the same time.

Of course with super crazy dV you could do crazy things...  But here is an analogy.

Suppose you are at the South Pole and want to get to the North Pole faster than half of an LEO period (say 45 minutes).  What do you do?  Can you trade payload mass for transit time?

(There is a way to do it, but it is very dV expensive)
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Nomadd on 01/22/2017 02:25 am
I wrote a simulator some years ago, and what I found was that for realistic deltaV, it wasn't really matter of mass...

You could send a payload to Mars early, but it wouldn't get there much sooner.  you could just wait on earth (which is catching up), launch on time, and get to Mars at the same time.

Of course with super crazy dV you could do crazy things...  But here is an analogy.

Suppose you are at the South Pole and want to get to the North Pole faster than half of an LEO period (say 45 minutes).  What do you do?  Can you trade payload mass for transit time?

(There is a way to do it, but it is very dV expensive)
Elon is already designing it. A vacuum tube with a train going twice LEO, so you still have a normal 1G force, but upside down. He's going to call it the Ludicrousloop.

Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: cro-magnon gramps on 01/22/2017 02:59 am
I wrote a simulator some years ago, and what I found was that for realistic deltaV, it wasn't really matter of mass...

You could send a payload to Mars early, but it wouldn't get there much sooner.  you could just wait on earth (which is catching up), launch on time, and get to Mars at the same time.

Of course with super crazy dV you could do crazy things...  But here is an analogy.

Suppose you are at the South Pole and want to get to the North Pole faster than half of an LEO period (say 45 minutes).  What do you do?  Can you trade payload mass for transit time?

(There is a way to do it, but it is very dV expensive)
Elon is already designing it. A vacuum tube with a train going twice LEO, so you still have a normal 1G force, but upside down. He's going to call it the Ludicrousloop.

So Nomadd should I next expect to be like the Glaswegian apprentice engineer, sent across the street to get a bucket of steam  ;D :o a "True" story from my ex father in law...
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: FutureSpaceTourist on 02/09/2017 06:03 pm
Quote
NASA's @Astro_Behnken and Eric Boe evaluate @SpaceX #CrewDragon designs for crew mission to @space_station: http://go.nasa.gov/1A4OVzi

https://twitter.com/commercial_crew/status/829766002820915200 (https://twitter.com/commercial_crew/status/829766002820915200)

Edit: here's the NASA blog posting

Quote
Astronauts Bob Behnken, left, and Eric Boe evaluated the controls, seating and other aspects of the crew compartment of SpaceX’s Crew Dragon spacecraft during a recent visit to the company’s headquarters in Hawthorne, California. Sitting in a mock-up of the Crew Dragon cockpit, the two studied many aspects of the layout including spacing of displays and ease of movement.

The testing is taking place as SpaceX develops the Crew Dragon with an eye toward launching the spacecraft into orbit in the near future on a flight test to and from the International Space Station. Later, the Crew Dragons, launching atop Falcon 9 rockets, will perform operational missions to rotate crews aboard the orbiting laboratory. Companies build high fidelity models of their spacecraft and systems to help determine everything from practicality and operation to fit and comfort.

Boeing also is building a spacecraft and launch system to take astronauts to and from the station. Both companies are developing their systems under contracts with NASA’s Commercial Crew Program as the agency strives to return America’s human launch capability with domestic companies.

Behnken and Boe along with Doug Hurley and Suni Williams are the four NASA astronauts who travel across the country to evaluate design and manufacturing by Boeing and SpaceX. The astronauts have not been assigned to specific test flights yet and are pooling their test pilot expertise and engineering prowess to help the companies meet NASA requirements. Other astronauts also take part in the analysis of spacecraft, launch vehicles and the myriad ground systems that are under construction to make sure they meet NASA’s strict requirements for use, safety and reliability. Photos by SpaceX.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: abaddon on 02/09/2017 06:09 pm
The inside of the capsule looks remarkably like a normal room.

In all seriousness, exciting stuff!
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: woods170 on 02/09/2017 07:37 pm
The inside of the capsule looks remarkably like a normal room.

In all seriousness, exciting stuff!

Much like a similar setup for Starliner: https://www.nasa.gov/feature/simulators-give-astronauts-glimpse-of-future-flights
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Doesitfloat on 02/09/2017 07:54 pm
The inside of the capsule looks remarkably like a normal room.

In all seriousness, exciting stuff!

Much like a similar setup for Starliner: https://www.nasa.gov/feature/simulators-give-astronauts-glimpse-of-future-flights

Yes but Starliner doesn't have Lumberjacks to help them out.  :)
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Folgers25 on 02/09/2017 08:50 pm
This is interesting. Looks like they went from a traditional stick set up to video game controls. Anyone know if there have been touchscreen flight controls or some kind of touchscreen MFD in space before?
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Oersted on 02/09/2017 11:10 pm
I strongly suspect that the Sept 1 anomaly has made May of 2018 nonworkable.  I think it will be pushed back until the next window.

Would a Falcon Heavy be able to push a Dragon 2 on a fast transit to Mars outside of the closest approach periods?

Ah, sorry, I now see it was more or less answered. That being said I would like to see some numbers...
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: whitelancer64 on 02/09/2017 11:14 pm
I strongly suspect that the Sept 1 anomaly has made May of 2018 nonworkable.  I think it will be pushed back until the next window.

Would a Falcon Heavy be able to push a Dragon 2 on a fast transit to Mars outside of the closest approach periods?

Define "fast transit," and no matter how you define it, the answer is: Yes, but not as fast and not efficiently.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: woods170 on 02/10/2017 06:30 am
The inside of the capsule looks remarkably like a normal room.

In all seriousness, exciting stuff!

Much like a similar setup for Starliner: https://www.nasa.gov/feature/simulators-give-astronauts-glimpse-of-future-flights

Yes but Starliner doesn't have Lumberjacks to help them out.  :)
Had to look twice to understand your post. :)
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Johnnyhinbos on 02/10/2017 10:52 am
Thought that was Bezos for a minute...
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: DanielW on 02/10/2017 05:19 pm
The inside of the capsule looks remarkably like a normal room.

In all seriousness, exciting stuff!

Much like a similar setup for Starliner: https://www.nasa.gov/feature/simulators-give-astronauts-glimpse-of-future-flights

Yes but Starliner doesn't have Lumberjacks to help them out.  :)
Had to look twice to understand your post. :)

That is actually a manikin displaying spacex's latest flight suit concept. They had to make a change after boeing took the "solid colors" idea.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: docmordrid on 02/18/2017 07:29 am
Elon Musk ✔ @elonmusk
Provided Dragon 2 demo missions go well, SpaceX is highly confident of being able to fly US astronauts in 2018 http://www.theverge.com/2017/2/16/14640618/nasa-spacex-boeing-astronaut-iss-2018 …
3:07 AM - 18 Feb 2017
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: FutureSpaceTourist on 02/18/2017 06:34 pm
In response to Elon's tweet:

Quote
@elonmusk Can u address specifics in GAO report? Past projections proved optimistic. Why is GAO wrong? What's different now?
https://twitter.com/spacecom/status/832991913741475841 (https://twitter.com/spacecom/status/832991913741475841)

Quote
@spacecom They are often right, but, in this case, we have already retired so much R&D risk on Dragon 2, that I feel very confident of 2018.
https://twitter.com/elonmusk/status/832992529872097280 (https://twitter.com/elonmusk/status/832992529872097280)
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: FutureSpaceTourist on 02/23/2017 07:09 pm
Quote
ASAP’s Frost: SpaceX agrees there will be seven flights in “frozen” configuration of the Block 5 version of Falcon 9 before crew flights.

https://twitter.com/stephenclark1/status/834850968542052354 (https://twitter.com/stephenclark1/status/834850968542052354)

Edit: bit more detail

Quote
ASAP's Frost: SpaceX has agreed to fly seven Block 5 Falcon 9s before flying crew, in response to concerns about constantly changing config.

https://twitter.com/flatoday_jdean/status/834851988240228352 (https://twitter.com/flatoday_jdean/status/834851988240228352)
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: guckyfan on 02/23/2017 07:23 pm
If I understand correctly, the uncrewed test flight and the pad abort could be part of the 7? Only the crewed test flight would require that number of flights?
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: rockets4life97 on 02/23/2017 07:49 pm
If I understand correctly, the uncrewed test flight and the pad abort could be part of the 7? Only the crewed test flight would require that number of flights?

This is my interpretation as well. So, the uncrewed flight will probably be one of the first Block Vs near the end of the year.

By mid-2018 they could have flown 6 more Block Vs if they are at a launch rate of 1 a month. Obviously, SpaceX is planning on a higher launch rate than that, but that is the cadence they've shown they can do (failures aside).
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: mme on 02/23/2017 08:27 pm
If I understand correctly, the uncrewed test flight and the pad abort could be part of the 7? Only the crewed test flight would require that number of flights?
I think you mean the inflight abort, not the pad abort. But I doubt that the inflight abort would count.  It may not even have a real second stage. I imagine that both uncrewed flights would count if they use new hardware (I believe they want 7 different rockets, not just 7 launches).

Either way this does not seem like an issue. If SpaceX has not flown 7 Block V rockets before the first crewed flight, something has gone horribly wrong.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: guckyfan on 02/23/2017 08:41 pm
I think you mean the inflight abort, not the pad abort. But I doubt that the inflight abort would count.  It may not even have a real second stage. I imagine that both uncrewed flights would count if they use new hardware (I believe they want 7 different rockets, not just 7 launches).

Either way this does not seem like an issue. If SpaceX has not flown 7 Block V rockets before the first crewed flight, something has gone horribly wrong.

Of course you are right, in flight abort, not pad abort. The main point I was thinking of was that they don't need to do 7 flights before they do those two missions. They need to complete 7 flights before the first crewed flight. I was unclear on this. You are right again that it should not be a problem for SpaceX to reach those 7 flights. Needing 7 flights before the unmanned Dragon 2 flight would introduce a fatal delay. They won't have 7 flights before end of this year.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: deruch on 02/23/2017 09:42 pm
One of the general problems in coverage/discussion of the crew program is that there is, IMO, some ambiguity in the usage of the term "crew flights".  Is the 1st crew flight/launch DM-2 (the demo mission with crew) or are we only counting the Post Certification Missions (PCMs)?  When NASA talks about "crew rotations", I feel it's clear.  Those are only considering PCMs.  But, I can't help but feel that there may be a bit of weaseling speech involved when Elon/Gwen/SpaceX talk about "launching crews/astronauts".  E.g. In response to the GAO, both have insisted that they feel very confident that they'll be flying US astronauts in 2018 (though in Elon's last tweet, he does seem to distinguish between the crewed demo mission and operational flights). 

So, with that background, do the statements coming out of the ASAP meeting suggest that SpaceX is committing to having launched 7 times with a frozen LV configuration prior to DM-2 (demo mission with crew)?  Or that they'll have launched at least that many prior to operational missions (PCMs/crew rotations)?
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: M.E.T. on 02/24/2017 07:27 am
Regarding not flying the Block 5 seven times in 2017.

If they have LC39, LC40 and Vandenberg in operation in the latter part of the year, 7 flights could require as little as 3-4 months. Assuming that they have the twice-a-month launch cadence down pat by then. A feat which would presumably be made somewhat more achievable by having the flights spread across three different launch facilities.

The constraints would then seem to be the start date for the manufacturing of the Block 5 (which based on the Iridium tweet was estimated to be around June), the manufacturing time required for seven Block 5 first stages, and the time required for the manufacturing of seven second stages.

Of course, my immediate thought on constraint three is whether SpaceX was able to use the downtime after Amos 6 to pile up a bunch of completed second stages in advance. I'm guessing not, based on the references to second stages being a bit of a bottleneck for launch cadence. But one wonders why they did not do so, in that case.


Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: cscott on 02/24/2017 11:48 am
Because the second stage was involved in Amos-6 and they needed to figure out what/whether changes were needed before continuing production.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: M.E.T. on 02/24/2017 11:50 am
Because the second stage was involved in Amos-6 and they needed to figure out what/whether changes were needed before continuing production.

Yes, I leaned in that direction too, although of course I don't know if that means the entire production line has to close down or if partial construction could have continued.

In any case, do we know what the rate of second stage production is now?
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: DOCinCT on 02/24/2017 07:03 pm
Because the second stage was involved in Amos-6 and they needed to figure out what/whether changes were needed before continuing production.
Yes, I leaned in that direction too, although of course I don't know if that means the entire production line has to close down or if partial construction could have continued.
In any case, do we know what the rate of second stage production is now?
Wouldn't be the same as the production rate of Falcon9 and center core of Falcon Heavy? It would be greater if they had to make 2nd stages for pre-flown F9s, but that itself would depend on whether or not the pre-flown core replaces or is supplemental the new cores.
Do we know how long it takes from start to finish for a core?
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Reflectiv on 02/24/2017 07:10 pm
The constraints would then seem to be the start date for the manufacturing of the Block 5 (which based on the Iridium tweet was estimated to be around June)
https://twitter.com/IridiumBoss/status/835198224889708544
Christian Daniels‏@CJDaniels77
I'll take it you'll be flying on what Elon calls block 5?

Matt [email protected]
Eventually, but not for next few flights I think.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: AndyX on 02/26/2017 09:03 pm
Dragon 2 flights...

https://www.nasaspaceflight.com/2017/02/commercial-rotation-us-segment-crew-increase-early/

Awesome feature article by Pete Harding, with cool L2 renders via Nathan Koga.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: yg1968 on 02/27/2017 03:14 pm
The news below affects crewed Dragon 2:

NASA quitely announced that it bought Soyuz seats for 2017 and 2018 from Boeing last week:

https://www.nasa.gov/feature/additional-crew-flights-boost-space-station-science-and-research/
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: envy887 on 02/27/2017 04:04 pm
The news below affects crewed Dragon 2:

NASA quitely announced that it bought Soyuz seats for 2017 and 2018 from Boeing last week:

https://www.nasa.gov/feature/additional-crew-flights-boost-space-station-science-and-research/

Are these replacing any commercial flights?
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: yg1968 on 02/27/2017 04:07 pm
The news below affects crewed Dragon 2:

NASA quitely announced that it bought Soyuz seats for 2017 and 2018 from Boeing last week:

https://www.nasa.gov/feature/additional-crew-flights-boost-space-station-science-and-research/

Are these replacing any commercial flights?

No. It eases pressure on the commercial companies. But NASA has already purchased six post-certification missions from each provider. For more on this, see Pete's article:

https://www.nasaspaceflight.com/2017/02/commercial-rotation-us-segment-crew-increase-early/
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: RoboGoofers on 02/28/2017 03:06 pm
Regarding the Moon flyby announcement: SpaceX is confident that Dragon 2 can operate fine BEO. Does anyone suspect that they've been upgrading components, or whatever has to be done, to make Dragon 2 better suited to operate beyond LEO?

Someone in the Red Dragon thread speculated that Dragon wasn't designed for the long earth-mars cruise. Assuming they upgraded components to make Dragon 2 robust enough for the cruise phase, it'll work fine for the Moon flyby. However, doesn't that mean that all Dragon 2s will be suitable for BEO, since SpaceX tries to iterate on one design instead of making lots of custom designs?

If so, it takes some wind out of the sales of Orion, as its justification vs Starliner/Dragon is that only it can do BEO.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: CuddlyRocket on 02/28/2017 09:37 pm
Regarding the Moon flyby announcement: SpaceX is confident that Dragon 2 can operate fine BEO. Does anyone suspect that they've been upgrading components, or whatever has to be done, to make Dragon 2 better suited to operate beyond LEO?

SpaceX normally plans ahead, so I imagine the Dragon 2 was designed from the start to operate beyond LEO. That might make it a little over-engineered for LEO operations, but they'll save on needing two designs etc.

BEO v LEO operations requires a more robust heatshield (though Dragon 1 has that already), long distance communications, longer-lasting ECLSS and possibly greater radiation protection. If they work for BEO, all should work just fine for LEO, but how much they're over-engineered for the latter probably depends on the actual design.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: CJ on 02/28/2017 10:26 pm
Regarding the Moon flyby announcement: SpaceX is confident that Dragon 2 can operate fine BEO. Does anyone suspect that they've been upgrading components, or whatever has to be done, to make Dragon 2 better suited to operate beyond LEO?

Someone in the Red Dragon thread speculated that Dragon wasn't designed for the long earth-mars cruise. Assuming they upgraded components to make Dragon 2 robust enough for the cruise phase, it'll work fine for the Moon flyby. However, doesn't that mean that all Dragon 2s will be suitable for BEO, since SpaceX tries to iterate on one design instead of making lots of custom designs?

If so, it takes some wind out of the sales of Orion, as its justification vs Starliner/Dragon is that only it can do BEO.

According to Elon, Dragon 2 does need mods for this mission, primarily the comms system. My guess is they'll need a significant upgrade for comms; a directional tranceiver antenna and associated hardware, which might or might not be compatible with some of all standard dragon2 comms gear (I have no idea).

*If* the above is true, over-engineered heat shield and all, then Dragon 2 is designed for the radiative environment of BEO (Radiation issues, perpetual sunlight, etc).

Regarding the comms system though... I wonder if that includes the Nav system? Because, if I remember right, Dragon1 relies on GPS a lot, and one can't do that above the altitude of the GPS birds. I have no idea how they'll handle the comms and nav issues, but it'll be interesting to find out.     
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: jg on 02/28/2017 11:06 pm
Regarding the Moon flyby announcement: SpaceX is confident that Dragon 2 can operate fine BEO. Does anyone suspect that they've been upgrading components, or whatever has to be done, to make Dragon 2 better suited to operate beyond LEO?

Someone in the Red Dragon thread speculated that Dragon wasn't designed for the long earth-mars cruise. Assuming they upgraded components to make Dragon 2 robust enough for the cruise phase, it'll work fine for the Moon flyby. However, doesn't that mean that all Dragon 2s will be suitable for BEO, since SpaceX tries to iterate on one design instead of making lots of custom designs?

If so, it takes some wind out of the sales of Orion, as its justification vs Starliner/Dragon is that only it can do BEO.

According to Elon, Dragon 2 does need mods for this mission, primarily the comms system. My guess is they'll need a significant upgrade for comms; a directional tranceiver antenna and associated hardware, which might or might not be compatible with some of all standard dragon2 comms gear (I have no idea).

*If* the above is true, over-engineered heat shield and all, then Dragon 2 is designed for the radiative environment of BEO (Radiation issues, perpetual sunlight, etc).

Regarding the comms system though... I wonder if that includes the Nav system? Because, if I remember right, Dragon1 relies on GPS a lot, and one can't do that above the altitude of the GPS birds. I have no idea how they'll handle the comms and nav issues, but it'll be interesting to find out.   

Actually, why do you think you can't do GPS above the birds? 

In fact you can do GPS above the orbits of the GPS constellation, as demonstrated even by at least one of the AMSAT amateur satellites...

Whether you can do GPS at Lunar distances accurately enough, I do not know.

Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: docmordrid on 02/28/2017 11:21 pm
>
Regarding the comms system though... I wonder if that includes the Nav system? Because, if I remember right, Dragon1 relies on GPS a lot, and one can't do that above the altitude of the GPS birds. I have no idea how they'll handle the comms and nav issues, but it'll be interesting to find out.   

FWIW,

http://spaceflight101.com/spacecraft/dragon/

Quote
Guidance, Navigation and Control

For navigational purposes, Dragon is outfitted with Inertial Measurement Units, GPS Systems, Iridium Recovery Beacons and Star Trackers. Attitude Control and Navigation in orbit is accomplished with the IMU and Star Trackers. Attitude Determination has an accuracy of 0.004 Degrees or smaller. Attitude Control is 0.012 degrees on each axis in Stationkeeping Mode. Dragon provides a fully autonomous Rendezvous and Docking System. For manned missions, a manual docking is also possible by using the override function to control the vehicle by hand.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: jg on 03/01/2017 01:52 am
>
Regarding the comms system though... I wonder if that includes the Nav system? Because, if I remember right, Dragon1 relies on GPS a lot, and one can't do that above the altitude of the GPS birds. I have no idea how they'll handle the comms and nav issues, but it'll be interesting to find out.   

FWIW,

http://spaceflight101.com/spacecraft/dragon/

Quote
Guidance, Navigation and Control

For navigational purposes, Dragon is outfitted with Inertial Measurement Units, GPS Systems, Iridium Recovery Beacons and Star Trackers. Attitude Control and Navigation in orbit is accomplished with the IMU and Star Trackers. Attitude Determination has an accuracy of 0.004 Degrees or smaller. Attitude Control is 0.012 degrees on each axis in Stationkeeping Mode. Dragon provides a fully autonomous Rendezvous and Docking System. For manned missions, a manual docking is also possible by using the override function to control the vehicle by hand.

GPS on AMSAT-OSCAR 40 well above the GPS constellation:

http://www.emergentspace.com/assets/1/7/ao40iongps2002_final.pdf

That is from the year 2000.


Star trackers are really, really easy to do these days.  Doing a "plate solve" is amazingly fast, and amateur telescopes do this kind of thing routinely with COTS software (e.g. TheSkyX).
Note an Apollo 13 kind of situation might make a star tracker ineffectual for a period due to reflections off of debris.

On a telescope, one often does a "closed loop slew", where you slew the telescope to approximately the right location, take a short exposure, find out where you are pointing to sub arc-second precision, and then move the telescope to exactly where you want it to be.

So I don't think navigation is a big problem.  Technology has come so far in the last 50 years that the hard part is the aerodynamic landing problem, but anything short of that is now pretty much a "solved problem" if you can compute orbits....  And SpaceX is routinely landing first stages within a few meters...

We don't live in 1968 anymore.  My hat is off to those who went to the moon with just an IMU and a small telescope sextant sort of arrangement.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Comga on 03/01/2017 04:30 am
(snip)
Star trackers are really, really easy to do these days.  Doing a "plate solve" is amazingly fast, and amateur telescopes do this kind of thing routinely with COTS software (e.g. TheSkyX).
Note an Apollo 13 kind of situation might make a star tracker ineffectual for a period due to reflections off of debris.
(snip)

Small point: Start trackers have to ignore things that don't correspond to stars, like gamma ray hits to the detector.  There is a paper discussing tracking with the star camera from the Clementine mission. It has an image of the stars with the moon in the field of view.  The attitude solution was found anyways. 
In short, if there are debris around the Dragon, they will still be able to determine attitude, but it won't be the most pressing issue. :o
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: quanthasaquality on 03/01/2017 04:43 am
So, how is SpaceX able to turn its Dragon into something which can go to cis-lunar space? Dragon and CST-100 seemed like light vehicles which just had to be reliable enough to get from earth to the ISS in low earth orbit a few hundred miles away, inside earth's magnetic field. The big, heavy Orion presumably has to be more reliable, as it would travel hundreds of thousands of miles away, in the full radiation of deep space. If Orion has a failure, there is no one around to help. The crew will die. Why did NASA start with Orion? why not just evolve the CST-100 in the same way?
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: vt_hokie on 03/01/2017 04:50 am
As I recall, SpaceX doesn't use traditional radiation hardened electronics.  Will good enough for LEO prove good enough for flying through the Van Allen belt and into cislunar space?  I guess they think so!
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Jcc on 03/01/2017 11:27 am
As I recall, SpaceX doesn't use traditional radiation hardened electronics.  Will good enough for LEO prove good enough for flying through the Van Allen belt and into cislunar space?  I guess they think so!

They use multiple redundant systems so if one is knocked out due to a radiation hit, the others continue working until the affected system can reset and reboot. As I understand it, the typical effect of radiation is to flip bits in the processor or memory, producing corrupted data, not actually damaging the electronics.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Jim on 03/01/2017 12:46 pm
So, how is SpaceX able to turn its Dragon into something which can go to cis-lunar space? Dragon and CST-100 seemed like light vehicles which just had to be reliable enough to get from earth to the ISS in low earth orbit a few hundred miles away, inside earth's magnetic field. The big, heavy Orion presumably has to be more reliable, as it would travel hundreds of thousands of miles away, in the full radiation of deep space. If Orion has a failure, there is no one around to help. The crew will die. Why did NASA start with Orion? why not just evolve the CST-100 in the same way?

The differences between a LEO and BEO spacecraft are in navigation and thermal control (and waste control).  With modern electronics, there is little differences between vehicles as far as reliability.   CST-100 and Dragon are viable as BEO vehicles.

The Orion is " big, heavy' because of propellant and not because it is BEO.

Boeing lost the competition to Lockheed for Orion.  CST-100 was developed later for commercial crew.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: meberbs on 03/01/2017 01:31 pm
As I recall, SpaceX doesn't use traditional radiation hardened electronics.  Will good enough for LEO prove good enough for flying through the Van Allen belt and into cislunar space?  I guess they think so!

They use multiple redundant systems so if one is knocked out due to a radiation hit, the others continue working until the affected system can reset and reboot. As I understand it, the typical effect of radiation is to flip bits in the processor or memory, producing corrupted data, not actually damaging the electronics.
That is one effect, but it also damages electronics. As a simple example JunoCam is only expected to last a limited number of orbits due to the radiation environment. This is the same camera used on Curiosity, so the interplanetary radiation environment won't quickly destroy electronics, and a backup should be good enough as long as your chip isn't too modern. (Modern electronics have smaller transistor gate sizes, which directly makes them less rad tolerant.)
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Norm38 on 03/01/2017 02:17 pm
They use multiple redundant systems so if one is knocked out due to a radiation hit, the others continue working until the affected system can reset and reboot. As I understand it, the typical effect of radiation is to flip bits in the processor or memory, producing corrupted data, not actually damaging the electronics.

That is true I beleive for low voltage logic, but in high voltage power supplies a MOSFET can fail short if hit by a high energy particle. (FET has to be off and blocking high voltage). There is extra derating that must be applied.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: DOCinCT on 03/01/2017 05:10 pm
So, how is SpaceX able to turn its Dragon into something which can go to cis-lunar space? Dragon and CST-100 seemed like light vehicles which just had to be reliable enough to get from earth to the ISS in low earth orbit a few hundred miles away, inside earth's magnetic field. The big, heavy Orion presumably has to be more reliable, as it would travel hundreds of thousands of miles away, in the full radiation of deep space. If Orion has a failure, there is no one around to help. The crew will die. Why did NASA start with Orion? why not just evolve the CST-100 in the same way?
The modifications needed for a cis-lunar mission are basically the same as needed for Dragon Lab
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: IainMcClatchie on 03/01/2017 07:14 pm
My understanding is that CMOS electronics in space can go into latchup as a result of a high energy particle hit.  A LEO satellite might go years between such events.  In the latchup state, the parasitic bipolar transistors underneath the CMOS transistors turn on, shorting power to ground.  The device heats up rapidly.

So, folks that use CMOS in space use power supplies that detect a rapid increase in current.  When so triggered, they not only shut down within a millisecond or so, they also dump the charge on the power-to-ground decoupling capacitors into resistors.  Once grounded, it shouldn't take longer than maybe tens of milliseconds for the latchup charge to leak away, at which point the device can be rebooted.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: rakaydos on 03/01/2017 10:43 pm
As I recall, SpaceX doesn't use traditional radiation hardened electronics.  Will good enough for LEO prove good enough for flying through the Van Allen belt and into cislunar space?  I guess they think so!

They use multiple redundant systems so if one is knocked out due to a radiation hit, the others continue working until the affected system can reset and reboot. As I understand it, the typical effect of radiation is to flip bits in the processor or memory, producing corrupted data, not actually damaging the electronics.
That is one effect, but it also damages electronics. As a simple example JunoCam is only expected to last a limited number of orbits due to the radiation environment. This is the same camera used on Curiosity, so the interplanetary radiation environment won't quickly destroy electronics, and a backup should be good enough as long as your chip isn't too modern. (Modern electronics have smaller transistor gate sizes, which directly makes them less rad tolerant.)
JunoCam isnt a fair comparison. it's not the INTERPLANETARY radiation that's an issue, it's the JOVIAN radiation.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: x15_fan on 03/02/2017 01:44 am
As I recall, SpaceX doesn't use traditional radiation hardened electronics.  Will good enough for LEO prove good enough for flying through the Van Allen belt and into cislunar space?  I guess they think so!

They use multiple redundant systems so if one is knocked out due to a radiation hit, the others continue working until the affected system can reset and reboot. As I understand it, the typical effect of radiation is to flip bits in the processor or memory, producing corrupted data, not actually damaging the electronics.
That is one effect, but it also damages electronics. As a simple example JunoCam is only expected to last a limited number of orbits due to the radiation environment. This is the same camera used on Curiosity, so the interplanetary radiation environment won't quickly destroy electronics, and a backup should be good enough as long as your chip isn't too modern. (Modern electronics have smaller transistor gate sizes, which directly makes them less rad tolerant.)
JunoCam isnt a fair comparison. it's not the INTERPLANETARY radiation that's an issue, it's the JOVIAN radiation.

Maybe, but I've seen ASICs on Earth latch up and fried by SEL event. Some of those high energy particles make it right into your data center and keep on going. If you have enough processors and enough time you'll get hit. We saw a trend so vendor put parts under SEM after grinding off the package to find massive thermal over-stress. Solution was to re-spin ASIC with more margin around vulnerable Features on the chip.


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Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Brovane on 03/02/2017 02:15 am
As I recall, SpaceX doesn't use traditional radiation hardened electronics.  Will good enough for LEO prove good enough for flying through the Van Allen belt and into cislunar space?  I guess they think so!
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: CuddlyRocket on 03/02/2017 05:07 am
Although I'm sure SpaceX engineers and their NASA advisers won't miss anything obvious, it's still enjoyable for us lay observers to discuss their options. Especially in the event of (da-da-daaah!) something going wrong! :)

Navigation: Primarily star trackers and inertial systems. Supplemented by radio ranging and doppler-shifting from Earth-based antennas. Plus, direct direction-finding from dish antennas etc; triangulation from widely spaced antennas. The Sun, Earth and Moon are pretty difficult to miss, so triangulation from their apparent directions (especially if you can see their terminators with respect to their apparent centers). You can also measure the apparent size of the Earth and Moon to find distance. Finally, there's dead reckoning from a previously known set of co-ordinates (the capsule is a ballistic object, unless it's under power).

(This does point up the need for reliable communications. May need to consider redundant steerable antennae on the Dragon.)

Waste: Store in plastic bags in a freezer (the Dragon 2 is designed with such facilities at NASA's request). One of those handy hoses connected to space would cut down on the volume. Might need a curtain depending on how well the two crew know each other or can be trusted to look the other way. (Though you can't turn your nose off! At least indefinitely.) Or have enough diapers for a week. Though I'm sure passengers will probably spring for a functional toilet.

Thermal (you can't cool off in Earth's shadow 40% of each orbit): Bigger radiators.

Radiation (principally from an unexpected solar flare): Point the heat shield towards it. Additional shielding internally (polyethylene sheets?); perhaps in the form of a storm shelter. Supplemented by placement of equipment, water supplies, rations etc. Carry radiation protection clothing such as lead aprons (maybe not lead, depending on the radiation threat) or build additional protection into the flight suits (which the crew will presumably put on if there's such an event).
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Roy_H on 03/02/2017 05:30 am
Is there any difference in radiation protection (for crew) between Orion and Dragon?
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Robotbeat on 03/02/2017 06:20 am
Is there any difference in radiation protection (for crew) between Orion and Dragon?
Mostly depends on the mass of any supplies they bring with them. Any kind of plastic or food or water will do, and it doesn't have to be integrated into the spacecraft. In fact, it's more efficient if it's directly attached to the astronaut!
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Ben the Space Brit on 03/02/2017 07:10 am
This is the interesting thing with SpaceX. As a private organisation, the answer to many "What about...?" and "How will they handle...?" questions have the answer: "Commercially privileged information, sorry." They are obliged to answer those questions to regulators, their insurers and, under certain circumstances, their customers. However, even those questions do not automatically make it into the public record due to long-established commercial confidentiality laws.

Translation: These questions may already be answered but, as they're proprietary, it's entirely up to Musk whether he wants to tell us.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: quanthasaquality on 03/02/2017 07:45 am
As I recall, SpaceX doesn't use traditional radiation hardened electronics.  Will good enough for LEO prove good enough for flying through the Van Allen belt and into cislunar space?  I guess they think so!

SpaceX wins on price, if you're willing to tolerate the chance of failure. I'd trust SpaceX with my luggage. I wouldn't trust SpaceX with my life.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: guckyfan on 03/02/2017 08:33 am
Thinking of adding delta-v to Dragon for cislunar operation. They could add propellant tanks plus maybe Dracos in the trunk. But what would be the max mass for abort? Could that propulsion package be built to be left behind in case of abort?
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: IRobot on 03/02/2017 10:46 am
As I recall, SpaceX doesn't use traditional radiation hardened electronics.  Will good enough for LEO prove good enough for flying through the Van Allen belt and into cislunar space?  I guess they think so!
They already flew F9's second stage well beyond Van Allen belt, DSCOVR launch.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: rpapo on 03/02/2017 11:33 am
As I recall, SpaceX doesn't use traditional radiation hardened electronics.  Will good enough for LEO prove good enough for flying through the Van Allen belt and into cislunar space?  I guess they think so!
They already flew F9's second stage well beyond Van Allen belt, DSCOVR launch.
That's true, but that stage electronics should have been shut down long before it even passed through even the inner belt, let alone the outer belt.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Silmfeanor on 03/02/2017 12:18 pm
As I recall, SpaceX doesn't use traditional radiation hardened electronics.  Will good enough for LEO prove good enough for flying through the Van Allen belt and into cislunar space?  I guess they think so!
They already flew F9's second stage well beyond Van Allen belt, DSCOVR launch.
That's true, but that stage electronics should have been shut down long before it even passed through even the inner belt, let alone the outer belt.

I wonder where this picture came from then. That should be above the belt, right?
(source - http://www.spacex.com/news/2015/02/11/spacex-launches-dscovr-satellite-deep-space-orbit (http://www.spacex.com/news/2015/02/11/spacex-launches-dscovr-satellite-deep-space-orbit) )
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: ugordan on 03/02/2017 01:00 pm
Stage electronics happening to work after their primary mission phase is over is not the same as requiring them to work for the primary mission.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: envy887 on 03/02/2017 01:18 pm
Stage electronics happening to work after their primary mission phase is over is not the same as requiring them to work for the primary mission.

Block 5 is expected to do direct GEO insertions, which will require functionality after transiting more of the belts than a trans-lunar injection.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: ugordan on 03/02/2017 01:20 pm
Stage electronics happening to work after their primary mission phase is over is not the same as requiring them to work for the primary mission.

Block 5 is expected to do direct GEO insertions, which will require functionality after transiting more of the belts than a trans-lunar injection.

Perhaps, but the image posted above as proof (?) of something is demonstrably NOT a Block 5 vehicle.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Brovane on 03/02/2017 01:21 pm
As I recall, SpaceX doesn't use traditional radiation hardened electronics.  Will good enough for LEO prove good enough for flying through the Van Allen belt and into cislunar space?  I guess they think so!

SpaceX wins on price, if you're willing to tolerate the chance of failure. I'd trust SpaceX with my luggage. I wouldn't trust SpaceX with my life.

If you are looking for safe way to spend your fortune, buying a ticket to go into space isn't on that list.   

When you say you wouldn't trust SpaceX with your life, what benchmark are you comparing SpaceX against?
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: envy887 on 03/02/2017 02:05 pm
Stage electronics happening to work after their primary mission phase is over is not the same as requiring them to work for the primary mission.

Block 5 is expected to do direct GEO insertions, which will require functionality after transiting more of the belts than a trans-lunar injection.

Perhaps, but the image posted above as proof (?) of something is demonstrably NOT a Block 5 vehicle.

Anything launching Dragon 2 is going to be Block 5, though the US will be spent before reaching either belt so I'm not sure how it's relevant.

Dragon 2 has always been intended to go BLEO. I see no plausible indication that SpaceX designed it for LEO-only with the intention to later revise it for BLEO radiation environments.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: ugordan on 03/02/2017 02:13 pm
Stage electronics happening to work after their primary mission phase is over is not the same as requiring them to work for the primary mission.

Block 5 is expected to do direct GEO insertions, which will require functionality after transiting more of the belts than a trans-lunar injection.

Perhaps, but the image posted above as proof (?) of something is demonstrably NOT a Block 5 vehicle.

Anything launching Dragon 2 is going to be Block 5, though the US will be spent before reaching either belt so I'm not sure how it's relevant.

My original comment was a direct response to the image posted above and in particular the comment about how they already flew a stage through the Van Allen belts with DSCOVR (they actually flew one already with SES-8). As if that *proved* something. To which you replied with a comment about a future block upgrade to the vehicle.

Dragon 2 has always been intended to go BLEO. I see no plausible indication that SpaceX designed it for LEO-only with the intention to later revise it for BLEO radiation environments.

I never said anything about Dragon.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: envy887 on 03/02/2017 02:42 pm
The picture was apparently posted to support the idea that Dragon 2 can survive BLEO radiation environments, though the connection is tenuous at best. Certainly not proof.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: gongora on 03/02/2017 02:52 pm
Stage electronics happening to work after their primary mission phase is over is not the same as requiring them to work for the primary mission.

Block 5 is expected to do direct GEO insertions, which will require functionality after transiting more of the belts than a trans-lunar injection.

The Falcon second stage with a mission kit for extended operations is expected to do GEO insertions, it may not have anything to do with Block 5 and could very well fly before block 5 depending on what they decide to do for FH Demo.  (STP-2 mission would probably have the mods on the second stage but it's not going to GEO).
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: philw1776 on 03/02/2017 04:58 pm
As I recall, SpaceX doesn't use traditional radiation hardened electronics.  Will good enough for LEO prove good enough for flying through the Van Allen belt and into cislunar space?  I guess they think so!

SpaceX wins on price, if you're willing to tolerate the chance of failure. I'd trust SpaceX with my luggage. I wouldn't trust SpaceX with my life.

Remember Apollo astronauts comments about flying spacecraft from the lowest bidder?
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: envy887 on 03/02/2017 05:30 pm
Stage electronics happening to work after their primary mission phase is over is not the same as requiring them to work for the primary mission.
Block 5 is expected to do direct GEO insertions, which will require functionality after transiting more of the belts than a trans-lunar injection.
Could you provide a source for this statement?

Gwynne Shotwell last August:

Are you looking to allow direct GEO insertion with the Falcon Heavy?
Yes, looking into it in particular with the DoD.
https://forum.nasaspaceflight.com/index.php?topic=40890.0

And other SpaceX people have several times said they are planning to support direct to GEO for DoD missions.

As gongora said, might be available as soon as STP-2 which likely won't even be Block 5.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: guckyfan on 03/02/2017 06:48 pm
Capability to go directly to GEO is on the SpaceX Falcon Heavy page as part of the second stage description.

Quote
The engine can be restarted multiple times to place payloads into a variety of orbits including low Earth, geosynchronous transfer orbit (GTO) and  geosynchronous orbit (GSO).
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Joffan on 03/05/2017 03:49 pm

Remember Apollo astronauts comments about flying spacecraft from the lowest bidder?

There is, of course, a word that should be added into that observation: "spacecraft from the lowest qualified bidder". The Apollo spacecraft were fabricated and built under strong technical review.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: clongton on 03/05/2017 06:55 pm
The big, heavy Orion presumably has to be more reliable, as it would travel hundreds of thousands of miles away, in the full radiation of deep space.

At ISDC in Orlando in 2009 Ross, Steve and I spent a fair amount of time with Lockheed Martian executives and the size of the spacecraft was part of those conversations. It was 7-1/2 years ago so the point is mute now but the mass of Orion is, as Jim correctly stated, because of the amount of propellant it had to carry. But there was a more basic, underlying condition that made the spacecraft large enough to require that amount of propellant; it had to be too big for either of the existing EELVs to carry to orbit. This justified the development of Ares-I as a CLV. Without Ares-I, Ares-V could not fly and CxP would fall apart. It was all very political.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: cwr on 03/05/2017 09:04 pm

Remember Apollo astronauts comments about flying spacecraft from the lowest bidder?

There is, of course, a word that should be added into that observation: "spacecraft from the lowest qualified bidder". The Apollo spacecraft were fabricated and built under strong technical review.

I agree with the quote correction.

I may be mis-remembering but wasn't this quote by one of John Glenn or Alan Shepherd after they had seen an Atlas explode some months before Glenn's MA-6 flight. I think that was the MA-3 flight that was destroyed by the RSO.

Carl
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: MP99 on 03/07/2017 07:42 pm
Is there any difference in radiation protection (for crew) between Orion and Dragon?
Mostly depends on the mass of any supplies they bring with them. Any kind of plastic or food or water will do, and it doesn't have to be integrated into the spacecraft. In fact, it's more efficient if it's directly attached to the astronaut!
Interesting related recent news item:-

https://www.engadget.com/2017/03/05/astronaut-anti-radiation-vest-gets-moon-trial/

Cheers, Martin
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Lars-J on 03/08/2017 05:07 pm
ECLSS Put to the Test for Commercial Crew Missions

https://www.nasa.gov/feature/eclss-put-to-the-test-for-commercial-crew-missions

This is a NASA article about the ECLSS (life support) work for Dragon 2. There's plenty of detail to be seen in these three images that accompany the article:
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: mattstep on 03/08/2017 06:20 pm
There's plenty of detail to be seen in these three images that accompany the article:

Ha! I wonder if the smoke detector in the second image will be standard :p

That's an interesting look through the glass floor in the third image. Lots 'o bits under there. If you compare the floors in the second and third images, they used a clear floor material during testing but it looks quite old and scratched. A good excuse for a slick branded replacement for the official photo shoot.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: docmordrid on 03/08/2017 08:21 pm
Jus out of curiosity, how thick is the pressure hull?
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Kansan52 on 03/08/2017 10:22 pm
Ok, two are wearing masks and other two not. Anyone know why?
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: DavidH on 03/08/2017 10:31 pm
Ok, two are wearing masks and other two not. Anyone know why?
Facial hair.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: IainMcClatchie on 03/08/2017 10:35 pm
Two two guys without masks both have microphones.  The other two don't.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Kansan52 on 03/08/2017 11:07 pm
Two two guys without masks both have microphones.  The other two don't.

Very likely. Also, one did seem to be covering facial hair. It may be that simple.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Johnnyhinbos on 03/09/2017 02:06 am
There's plenty of detail to be seen in these three images that accompany the article:

Ha! I wonder if the smoke detector in the second image will be standard :p

That's an interesting look through the glass floor in the third image. Lots 'o bits under there. If you compare the floors in the second and third images, they used a clear floor material during testing but it looks quite old and scratched. A good excuse for a slick branded replacement for the official photo shoot.
It's for when lunar astronauts Kanye and K Kardashian attempt to take an e-cig break after the mondo instagram selfie extravaganza while shooting the "backside" of the moon. You know, because that's where we're at...
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: ScottMC on 03/19/2017 05:25 pm
NASA TV: Release of SpaceX Dragon Capsule From The ISS

https://www.youtube.com/watch?v=p3aREIoaD6A?t=001

https://www.youtube.com/watch?v=p3aREIoaD6A

Heard the following comments during the Dragon unberthing operations, regarding a 90 minute test performed by Dragon in preparation for crew Dragon.  The comment is located between 1:52 and 2:47 in the video linked above.

Quote from: NASA TV Commentator
Engineers called (for) an IDA selfie.  Actually manoeuvring Dragon in front of the future docking port of the Commercial Crew vehicles.  The Commercial Crew vehicles that will be carrying astronauts from the United States and other partner agencies launching from the United States in the future.  Dragon using its thermal images and LIDAR just to help better understand the reflective environment of that IDA, basically a test to acquire some data that will be used for the future crewed Dragon during what's known as its proximity ops.  Those close in operations right before actual docking... and that took about 90 minutes.

Edit: video was trimmed, so time stamp has changed
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Comga on 03/19/2017 09:28 pm
NASA TV: Release of SpaceX Dragon Capsule From The ISS

Heard the following comments during the Dragon unberthing operations, regarding a 90 minute test performed by Dragon in preparation for crew Dragon.  The comment is located between 6:28 and 7:10 in the video linked above.

Quote from: NASA TV Commentator
Engineers called (for) an IDA selfie.  Actually manoeuvring Dragon in front of the future docking port of the Commercial Crew vehicles.  The Commercial Crew vehicles that will be carrying astronauts from the United States and other partner agencies launching from the United States in the future.  Dragon using its thermal images and LIDAR just to help better understand the reflective environment of that IDA, basically a test to acquire some data that will be used for the future crewed Dragon during what's known as its proximity ops.  Those close in operations right before actual docking... and that took about 90 minutes.

Can anyone explain this?
("IDA selfie"?  ::)   Not really....)
The IDA is on the forward port.
These observations need to be done at short range, well within the Keep Out Sphere.
In the post-release video we see the Dragon retreating to nadir.
It does not seem like these observations were performed this morning.

It's a great idea because there are some details in the IDA spec that just aren't correct.  There are theoretical values that need to be measured by flight sensors before being used to guide docking.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: ScottMC on 03/19/2017 10:04 pm
NASA TV: Release of SpaceX Dragon Capsule From The ISS

Heard the following comments during the Dragon unberthing operations, regarding a 90 minute test performed by Dragon in preparation for crew Dragon.  The comment is located between 6:28 and 7:10 in the video linked above.

Quote from: NASA TV Commentator
Engineers called (for) an IDA selfie.  Actually manoeuvring Dragon in front of the future docking port of the Commercial Crew vehicles.  The Commercial Crew vehicles that will be carrying astronauts from the United States and other partner agencies launching from the United States in the future.  Dragon using its thermal images and LIDAR just to help better understand the reflective environment of that IDA, basically a test to acquire some data that will be used for the future crewed Dragon during what's known as its proximity ops.  Those close in operations right before actual docking... and that took about 90 minutes.

Can anyone explain this?
("IDA selfie"?  ::)   Not really....)
The IDA is on the forward port.
These observations need to be done at short range, well within the Keep Out Sphere.
In the post-release video we see the Dragon retreating to nadir.
It does not seem like these observations were performed this morning.

It's a great idea because there are some details in the IDA spec that just aren't correct.  There are theoretical values that need to be measured by flight sensors before being used to guide docking.

I stopped transcribing a little too soon.  He carried on to say...

Quote from: NASA TV Commentator
... and that took about 90 minutes, and then once that was complete ground controllers again commanded the Canadarm2 which is still holding Dragon into its release attitude where it has been sitting for the last several hours.

My understanding is that the Canadarm2 was used as a selfie stick and Dragon was the camera used to take various "photos" of the IDA.

Edit: Formatting
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Johnnyhinbos on 03/20/2017 01:14 am
I thought this was the Dragon 2 thread?
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Robotbeat on 03/20/2017 01:27 am
I thought this was the Dragon 2 thread?
The previous post is relevant to Dragon 2, since it's basically testing out how the Dragon sensors will work.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Comga on 03/20/2017 03:37 am
NASA TV: Release of SpaceX Dragon Capsule From The ISS

Heard the following comments during the Dragon unberthing operations, regarding a 90 minute test performed by Dragon in preparation for crew Dragon.  The comment is located between 6:28 and 7:10 in the video linked above.

Quote from: NASA TV Commentator
Engineers called (for) an IDA selfie.  Actually manoeuvring Dragon in front of the future docking port of the Commercial Crew vehicles.  The Commercial Crew vehicles that will be carrying astronauts from the United States and other partner agencies launching from the United States in the future.  Dragon using its thermal images and LIDAR just to help better understand the reflective environment of that IDA, basically a test to acquire some data that will be used for the future crewed Dragon during what's known as its proximity ops.  Those close in operations right before actual docking... and that took about 90 minutes, and then once that was complete ground controllers again commanded the Canadarm2 which is still holding Dragon into its release attitude where it has been sitting for the last several hours..

My understanding is that the Canadarm2 was used as a selfie stick and Dragon was the camera used to take various "photos" of the IDA.

Ah!  Forget most of my earlier post.
It's still a great idea because there are some details in the IDA spec that just aren't correct.  There are theoretical values that need to be measured by flight sensors before being used to guide docking.
Now they have real data.
I assume this was done with the standard SpaceX rendezvous lidar in the bay near the grapple fixture.
How far away from the IDA can the Canadarm hold a Dragon?
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: jfallen on 03/24/2017 10:59 am
Anything noticed on the new Dragon 2 photos circling around on social media?   Are these pictures of a completed Dragon 2, or old pictures of a mock-up?  It also looks like one of the photos has a glimpse of a space suit.  Has anyone else seen these?  I'll try to find a link.

Found a link:
http://www.nbcnews.com/mach/science/look-inside-spacex-capsule-may-take-two-beyond-moon-n728336?cid=sm_npd_nn_fb_mc
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Ben the Space Brit on 03/24/2017 11:29 am
If it's the same vehicle that Musk introduced at the roll-out presser, she's been refitted inside. The main console has been altered (for example, the single central manual attitude control stick has been removed) and the interior has been fitted out with white formed plastic replacing the corrugated aluminium finish she had at the presser.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Robotbeat on 03/24/2017 11:37 am
Machined isogrid, not corrugated. #nitpick
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: ethan829 on 03/24/2017 11:44 am
Anything noticed on the new Dragon 2 photos circling around on social media?   Are these pictures of a completed Dragon 2, or old pictures of a mock-up?  It also looks like one of the photos has a glimpse of a space suit.  Has anyone else seen these?  I'll try to find a link.

Found a link:
http://www.nbcnews.com/mach/science/look-inside-spacex-capsule-may-take-two-beyond-moon-n728336?cid=sm_npd_nn_fb_mc (http://www.nbcnews.com/mach/science/look-inside-spacex-capsule-may-take-two-beyond-moon-n728336?cid=sm_npd_nn_fb_mc)

They appear to be the same photos posted to SpaceX's flickr page in 2015.
https://www.flickr.com/photos/spacex/20683882494/ (https://www.flickr.com/photos/spacex/20683882494/)
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Chris Bergin on 04/07/2017 09:51 pm
Dragon 2 update via NASA Status - via Chris Gebhardt:

https://www.nasaspaceflight.com/2017/04/commercial-crew-tight-achievable-timeline-2018/
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: eric_astro on 04/07/2017 10:19 pm
Going from the Shuttle to a capsule (with a launch escape system/conservative thermal protection), and NASA's calculations show they can't meet a 1 in 200 LOC benchmark? I've read  threads on this site questioning how accurate their MMOD estimates are (compare the almost 50 years of Soyuz operations).
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: eric_astro on 04/07/2017 10:46 pm
What do these loss of crew benchmarks mean for the viability of space tourism?
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: punder on 04/07/2017 11:04 pm
What do these loss of crew benchmarks mean for the viability of space tourism?

People pay up up to six figures for an Everest ascent, while facing a 1 in 25 "LOC."
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: meekGee on 04/07/2017 11:11 pm
Going from the Shuttle to a capsule (with a launch escape system/conservative thermal protection), and NASA's calculations show they can't meet a 1 in 200 LOC benchmark? I've read  threads on this site questioning how accurate their MMOD estimates are (compare the almost 50 years of Soyuz operations).

I've always considered the very idea ludicrous. It's not just the design, it's the myriad ways in which the flying hardware can deviate from the design (so incorporating the "known unknowns", and even the "unknown unknowns")

And reality proves just how "inaccurate" these figures are.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Comga on 04/08/2017 03:30 am
Quote
Progress over the last few months and revealed that, while the timeline is tight, the two companies are on track for their scheduled crew demo flights of Dragon and Starliner in 2018.

As stated later, this means that it's not physically impossible to meet the current schedule but highly unlikely.

And I agree with the posts above. The MMOD fear seems overblown. There is excellent data from twenty years with the ISS. Even with the much greater area, has there ever been an MMOD strike on the ISS that threatened pressure containment or vital systems?

Cue the ultra-safe and MMOD impervious Soyuz.
At least Boeing wins either way.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Jcc on 04/10/2017 08:30 pm
I'm sure this is not a likely scenario, but why can't NASA grant provisional certification to begin flying commercial crew, but require additional improvements in MMOD safety within 2 years or something? That is not how the contract was written, but if they have a contract modification and probably award additional money to Boeing and SpaceX to do so, it would avoid excessive delay in beginning commercial crew flights. The MMOD requirements were clearly not well understood in the beginning, and it seems like NASA is moving the goalposts.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: whitelancer64 on 04/10/2017 09:02 pm
*snip*
There is excellent data from twenty years with the ISS. Even with the much greater area, has there ever been an MMOD strike on the ISS that threatened pressure containment or vital systems?
*snip*

Yes. There are a couple of significant holes through the solar arrays, but the worst damage (so far) has been to the radiators. Some think that the persistent leaking issues are from small MMOD strikes, but as far as I know that's not substantiated.

However, to my knowledge, the biggest damage to the ISS (so far) is a 12-inch gash on one of the PV radiator covers, reported on NSF in 2014:

https://www.nasaspaceflight.com/2014/07/iss-managers-evaluating-mmod-radiator/

Pure luck that didn't knock out the radiator entirely. Impact at a different angle and it would have.

The ISS pressure vessels are pretty heavily armored with MMOD blankets, and these are periodically replaced when they accumulate too much damage. As far as I know they have no significant damage.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Herb Schaltegger on 04/10/2017 09:17 pm
*snip*
There is excellent data from twenty years with the ISS. Even with the much greater area, has there ever been an MMOD strike on the ISS that threatened pressure containment or vital systems?
*snip*

Yes. There are a couple of significant holes through the solar arrays, but the worst damage (so far) has been to the radiators. Some think that the persistent leaking issues are from small MMOD strikes, but as far as I know that's not substantiated.

However, to my knowledge, the biggest damage to the ISS (so far) is a 12-inch gash on one of the PV radiator covers, reported on NSF in 2014:

https://www.nasaspaceflight.com/2014/07/iss-managers-evaluating-mmod-radiator/

Pure luck that didn't knock out the radiator entirely. Impact at a different angle and it would have.

The ISS pressure vessels are pretty heavily armored with MMOD blankets, and these are periodically replaced when they accumulate too much damage. As far as I know they have no significant damage.

There are also a couple good nicks to Cupola windows, but so far nothing that significantly impacts the structurual integrity of the pressure pane(s). The inner scratch panes and outer pane were originally designed to allow on-orbit replacement though I do not know if that design feature survived the "off-shoring" of Cupola production when the Space Station Freedom program was folded, spindled and mutilated into what became the ISS.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: woods170 on 04/11/2017 07:13 am
*snip*
There is excellent data from twenty years with the ISS. Even with the much greater area, has there ever been an MMOD strike on the ISS that threatened pressure containment or vital systems?
*snip*

Yes. There are a couple of significant holes through the solar arrays, but the worst damage (so far) has been to the radiators. Some think that the persistent leaking issues are from small MMOD strikes, but as far as I know that's not substantiated.

However, to my knowledge, the biggest damage to the ISS (so far) is a 12-inch gash on one of the PV radiator covers, reported on NSF in 2014:

https://www.nasaspaceflight.com/2014/07/iss-managers-evaluating-mmod-radiator/

Pure luck that didn't knock out the radiator entirely. Impact at a different angle and it would have.

The ISS pressure vessels are pretty heavily armored with MMOD blankets, and these are periodically replaced when they accumulate too much damage. As far as I know they have no significant damage.

There are also a couple good nicks to Cupola windows, but so far nothing that significantly impacts the structurual integrity of the pressure pane(s). The inner scratch panes and outer pane were originally designed to allow on-orbit replacement though I do not know if that design feature survived the "off-shoring" of Cupola production when the Space Station Freedom program was folded, spindled and mutilated into what became the ISS.
Yes, that feature did in fact survive the "off-shoring". Even the replacement of inner pressure-bearing panes survived this. Somewhere here (probably L2) there are images of the aluminium pressure-bearing panels that will be placed on the outside to allow replacement of an inner pressure-bearing pane.

But I digress.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: FutureSpaceTourist on 04/11/2017 02:15 pm
A fairly brief NASA blog:

Quote
Astronauts Work with Crew Dragon Qualification Vehicle

Bob Behnken and Eric Boe, two of NASA’s four veteran astronauts who supported SpaceX as it refines its crew transportation system designs, checked out the Crew Dragon being used for qualification testing. NASA astronauts routinely travel to industry facilities during spacecraft and mission development to train and offer insights to engineers.

As seen here, Behken is evaluating the Crew Dragon’s hatches. The top hatch, at the nose of the spacecraft, will be the connecting port at the International Space Station. The side hatch will be the entryway for crews getting into the spacecraft when on Earth.

The Crew Dragon spacecraft and related test vehicles are being manufactured at SpaceX’s headquarters and factory in Hawthorne, California. The Crew Dragon is being built to routinely fly four astronauts to the International Space Station although it can carry up to seven people. Flight tests, first without a crew then with astronauts aboard, will take place before operational crew rotation missions.

NASA also partnered with Boeing to build and operate a separate, independent space system called the CST-100 Starliner to carry astronauts to the station. Both vehicles are being developed in close coordination with NASA’s Commercial Crew Program. Photos by SpaceX.

This entry was posted in NASA on April 11, 2017 by Steven Siceloff.

https://blogs.nasa.gov/commercialcrew/2017/04/11/astronauts-work-with-crew-dragon-qualification-vehicle/ (https://blogs.nasa.gov/commercialcrew/2017/04/11/astronauts-work-with-crew-dragon-qualification-vehicle/)

Edit: found better hi-res photos
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: SWGlassPit on 04/12/2017 05:07 pm
Yes. There are a couple of significant holes through the solar arrays, but the worst damage (so far) has been to the radiators. Some think that the persistent leaking issues are from small MMOD strikes, but as far as I know that's not substantiated.

However, to my knowledge, the biggest damage to the ISS (so far) is a 12-inch gash on one of the PV radiator covers, reported on NSF in 2014:

https://www.nasaspaceflight.com/2014/07/iss-managers-evaluating-mmod-radiator/

Pure luck that didn't knock out the radiator entirely. Impact at a different angle and it would have.

The ISS pressure vessels are pretty heavily armored with MMOD blankets, and these are periodically replaced when they accumulate too much damage. As far as I know they have no significant damage.

Bolded portion is patently incorrect.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Comga on 04/12/2017 05:17 pm
Yes. There are a couple of significant holes through the solar arrays, but the worst damage (so far) has been to the radiators. Some think that the persistent leaking issues are from small MMOD strikes, but as far as I know that's not substantiated.

However, to my knowledge, the biggest damage to the ISS (so far) is a 12-inch gash on one of the PV radiator covers, reported on NSF in 2014:

https://www.nasaspaceflight.com/2014/07/iss-managers-evaluating-mmod-radiator/

Pure luck that didn't knock out the radiator entirely. Impact at a different angle and it would have.

The ISS pressure vessels are pretty heavily armored with MMOD blankets, and these are periodically replaced when they accumulate too much damage. As far as I know they have no significant damage.

Bolded portion is patently incorrect.

The rest is not true either.  Look at this image.  Uncovered aluminum exterior
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: SWGlassPit on 04/12/2017 05:22 pm
The aluminum exterior is the outer layer of the MMOD shield configuration.  Multiple layers are involved.  Virtually none of what you see is pressure-bearing structure.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Kansan52 on 04/12/2017 05:36 pm
Astronaut Bob Behnken seems to be enjoying climbing around the Dragon.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: jfallen on 05/01/2017 06:16 pm
Its been kind of quiet on Dragon 2 info.  Is there still a chance it could fly this year or is it going to slip into 2018?
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: IntoTheVoid on 05/22/2017 02:56 am
Its been kind of quiet on Dragon 2 info.  Is there still a chance it could fly this year or is it going to slip into 2018?

A Long term L2 schedule this week has DM-1 as March 9, 2018. Obviously very fluid with it being so far away.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Dante80 on 05/22/2017 06:33 am
Looking at some new pictures posted in the SpaceX website. Seems like SpaceX has taken Isogrid to the next level (although I guess some of the panels are not isotropic).

Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: RDMM2081 on 05/22/2017 08:15 pm
Looking at some new pictures posted in the SpaceX website. Seems like SpaceX has taken Isogrid to the next level (although I guess some of the panels are not isotropic).

Very nice find!
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Lars-J on 05/22/2017 08:42 pm
Looking at some new pictures posted in the SpaceX website. Seems like SpaceX has taken Isogrid to the next level (although I guess some of the panels are not isotropic).

I believe the bottom image is misnamed. It is actually a view DOWN, not up. (Otherwise we would see the docking adapter 'tunnel' which is not centered) The extreme wide angle may cause the confusion.

Edit: I added an image to illustrate the approximate camera position. (although the camera is probably slightly lower with a 180 degree view)
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: rory on 05/23/2017 03:08 pm
Does anyone have this University of Pittsburgh paper on PICA saved?  http://136.142.82.187/eng12/history/spring2013/pdf/3131.pdf

It was linked on NSF as recently as October (http://forum.nasaspaceflight.com/index.php?topic=41309.msg1598775#msg1598775) but seems to have gone dead since. I'm specifically curious about how the PICA-X tiles are applied to the Dragon — mechanically or with some sort of adhesive. Best I've been able to find is that FMI uses Phenolic Impregnated Felt (http://fibermaterialsinc.com/extreme-materials/pica/) to fill joints for regular (non -X) PICA.


EDIT: Managed to find it (https://forum.nasaspaceflight.com/index.php?topic=36039.msg1289588#msg1289588)! Attached below for convenience.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: FutureSpaceTourist on 05/23/2017 05:23 pm
Quote
Lightfoot: Astros to launch from U.S. soil "here in a couple of years." Docs say SpaceX targeting certification by Aug. '18, Boeing Oct. '18

https://twitter.com/flatoday_jdean/status/867062188938334210 (https://twitter.com/flatoday_jdean/status/867062188938334210)
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: chipguy on 05/23/2017 06:18 pm
Just curious but wouldn't the isogrid pattern be more effective on the outside of a pressure vessel?
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: envy887 on 05/23/2017 06:26 pm
Just curious but wouldn't the isogrid pattern be more effective on the outside of a pressure vessel?

For pressure containment the grid is unnecessary, see the Atlas and Centaur balloon tanks.

The grid is for extra strength under impact, bending, and compression loads, which would tend to buckle or puncture a balloon tank especially when unpressurized. They likely put it on the inside mainly for aerodynamic reasons.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: woods170 on 05/23/2017 07:55 pm
Just curious but wouldn't the isogrid pattern be more effective on the outside of a pressure vessel?

For pressure containment the grid is unnecessary, see the Atlas and Centaur balloon tanks.

The grid is for extra strength under impact, bending, and compression loads, which would tend to buckle or puncture a balloon tank especially when unpressurized. They likely put it on the inside mainly for aerodynamic reasons.
No. On neither Dragon 1, nor Dragon 2 is any part of the pressure vessel directly exposed to the atmosphere during ascent and descent. So, there isn't any aerodynamic reason for having the isogrid on the inside.

However, the Dragon 2 pressure vessel is a direct descendant of the Dragon 1 pressure vessel and uses much of the same tooling. The Dragon 1 pressure vessel had a smooth outside to aid in the application of MMOD protection layers and SPAM (SpaceX Proprietary Ablative Material). Basically, Dragon 2 inherited the design decision, to have the isogrid on the inside, from Dragon 1.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: biosehnsucht on 05/23/2017 09:57 pm
The pressure vessel isn't inside some other rigid structure that carries all those atmospheric / launch / etc loads, right? So it would still be what is carrying those loads, even if something is stuck on the outside of it. Not being directly exposed does not mean it doesn't carry the loads.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: envy887 on 05/23/2017 10:30 pm
No. On neither Dragon 1, nor Dragon 2 is any part of the pressure vessel directly exposed to the atmosphere during ascent and descent. So, there isn't any aerodynamic reason for having the isogrid on the inside.
Except this reason...
Quote
The Dragon 1 pressure vessel had a smooth outside to aid in the application of MMOD protection layers and SPAM (SpaceX Proprietary Ablative Material).
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: oiorionsbelt on 05/24/2017 12:55 am
I always wondered why Orion and Dragon reversed.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Dante80 on 05/24/2017 05:32 am
^^^btw. Orion uses an orthogrid formation.


CST-100 also has the isogrid on the exterior.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: woods170 on 05/24/2017 06:04 am
^^^btw. Orion uses an orthogrid formation.


CST-100 also has the isogrid on the exterior.

That is because CST-100, like Orion, attaches a secondary aeroshell structure over the pressure vessel. This secondary structure is the backbone for panels that actually make up the aeroshell.
The approach used by SpaceX is slightly different. On the upper half of the Dragon 1 pressure vessel the MMOD layers and SPAM were directly attached to the outside of the pressure vessel. That required a smooth outside of the pressure vessel. Hence the Dragon 1 pressure vessel having the isogrid on the inside.

Basically, the way in which the backshell TPS is applied to Dragon 1 much resembles how it was done on the Apollo Command Module (which also had a smooth exterior of the pressure vessel). The approach used by Boeing for CST-100 much resembles how it is done by Lockheed Martin on the Orion Crew Module.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Dante80 on 05/24/2017 06:52 am
Something also interesting to note is that SpaceX is not using the standard isogrid pattern. SpaceX is using quadrilateral Kites (https://en.wikipedia.org/wiki/Kite_(geometry)) for stringers instead of triangles. There are also some orthogrid (non isotropic) sections too, in the same panel. Very interesting. Moreover, three Kites produce one larger isogrid triangle. So you have two different isogrid equilateral patterns on the same panel, one smaller and one larger. Posting a sample below.

(http://i.imgur.com/R6a7VCY.png)

Those deltoids were first shown on the D2 reveal.

(http://i.imgur.com/tdWr1IFl.jpg) (http://i.imgur.com/tdWr1IF.jpg)

To the layman like me, it seems like their design can make the panels lighter, assuming they do have the same strength parameters/goals as what CST-100 and/or Orion has. At least to the untrained eye, those features look slimmer and shorter (less material used?).
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: DOCinCT on 05/24/2017 12:08 pm
Something also interesting to note is that SpaceX is not using the standard isogrid pattern. SpaceX is using quadrilateral Kites (https://en.wikipedia.org/wiki/Kite_(geometry)) for stringers instead of triangles. There are also some orthogrid (non isotropic) sections too, in the same panel. Very interesting. Moreover, three Kites produce one larger isogrid triangle. So you have two different isogrid equilateral patterns on the same panel, one smaller and one larger. Posting a sample below.

(http://i.imgur.com/R6a7VCY.png)

Those deltoids were first shown on the D2 reveal.

(http://i.imgur.com/tdWr1IFl.jpg) (http://i.imgur.com/tdWr1IF.jpg)

To the layman like me, it seems like their design can make the panels lighter, assuming they do have the same strength parameters/goals as what CST-100 and/or Orion has. At least to the untrained eye, those features look slimmer and shorter (less material used?).
Thought that a context photo (form the SpaceX gallery) might help.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: deruch on 05/26/2017 01:44 am
specifically curious about how the PICA-X tiles are applied to the Dragon — mechanically or with some sort of adhesive. Best I've been able to find is that FMI uses Phenolic Impregnated Felt (http://fibermaterialsinc.com/extreme-materials/pica/) to fill joints for regular (non -X) PICA.

Recommend watching the [email protected] Playlist from Dan Rasky: https://www.youtube.com/playlist?list=PLpEqMkxe7Xk_00sUp7g_wYkAIIuVbGvYz

IIRC, in a few of the videos he makes general references to PICA-X attachment to structures.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: vt_hokie on 05/31/2017 01:43 am
So, as we approach the 6 month until scheduled launch mark (likely to slip, I know), any guesses as to when we might see images of a nearly complete Crew Dragon vehicle?
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: woods170 on 05/31/2017 08:05 am
So, as we approach the 6 month until scheduled launch mark (likely to slip, I know), any guesses as to when we might see images of a nearly complete Crew Dragon vehicle?
Already has slipped into 2018 according to my sources at SpaceX.
No CCP launches, demo or otherwise, this year.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: vt_hokie on 05/31/2017 03:51 pm
No real surprise.  It looks like there are currently 13 Falcon 9 launches between now and the Crew Dragon Demo launch based on the existing manifest, and potentially a couple of Falcon Heavy launches, so I figured 2017 was a long shot at best but I hope that sets us up for an exciting 2018.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: gongora on 05/31/2017 03:57 pm
No real surprise.  It looks like there are currently 13 Falcon 9 launches between now and the Crew Dragon Demo launch based on the existing manifest, and potentially a couple of Falcon Heavy launches, so I figured 2017 was a long shot at best but I hope that sets us up for an exciting 2018.

Crew demo will be a high priority flight.  I doubt the state of the manifest will have much to do with its timing.  CRS flights and the NROL launch didn't really slip when the rest of the commercial manifest did after the AMOS-6 accident (aside from CRS not flying during the accident investigation of course).
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Chris Bergin on 05/31/2017 04:45 pm
Just so everyone is on the same page: DM update today:
https://forum.nasaspaceflight.com/index.php?topic=36966.msg1684564#msg1684564
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Confusador on 05/31/2017 06:43 pm
No real surprise.  It looks like there are currently 13 Falcon 9 launches between now and the Crew Dragon Demo launch based on the existing manifest, and potentially a couple of Falcon Heavy launches, so I figured 2017 was a long shot at best but I hope that sets us up for an exciting 2018.

Crew demo will be a high priority flight.  I doubt the state of the manifest will have much to do with its timing.  CRS flights and the NROL launch didn't really slip when the rest of the commercial manifest did after the AMOS-6 accident (aside from CRS not flying during the accident investigation of course).

Even if it weren't a priority, it'll be flying from 39A after 40 is online, so it should be doubly insulated from the rest of the manifest.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Dante80 on 05/31/2017 07:52 pm
Not if the FH demo damages the pad (FH won't fly from LC-40).
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: John.bender on 06/01/2017 12:36 am
I saw Jeff F tweet that Hans said SpaceX was still to launch uncrewed Dragon at the end of this year.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: woods170 on 06/01/2017 06:26 am
I saw Jeff F tweet that Hans said SpaceX was still to launch uncrewed Dragon at the end of this year.
Read this post: https://forum.nasaspaceflight.com/index.php?topic=36966.msg1684583#msg1684583

It's 2018, despite what politically correct statement was made. Public statements are usually about painting a pretty picture. The real picture is being painted in planning documentation. And as Chris B. has pointed out: the SpaceX DM-1 mission has been in 2018 in planning documentation for some time now.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Flying Beaver on 06/01/2017 09:15 pm
Loads of changes to Dragon 2 it seems. New pic and old.

What I see: No hatch window. Draco's have been moved. And fairings round the base of the truck fins. Among other things.

From NASA CC FB page.

https://www.facebook.com/NASACommercialCrew/photos/a.178361118927421.39226.159333767496823/1329791073784414/?type=3&theater (https://www.facebook.com/NASACommercialCrew/photos/a.178361118927421.39226.159333767496823/1329791073784414/?type=3&theater)
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Flying Beaver on 06/01/2017 10:25 pm
Noticed something. The nose cone is secured by the docking port latches, with the cone having simply a female ring. Very clever.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: FutureSpaceTourist on 06/07/2017 10:59 am
Quote
Crew Dragon Trainer Takes Shape at Kennedy
Posted on June 5, 2017 at 12:08 pm by Steven Siceloff.

NASA and SpaceX engineers are working together at NASA’s Kennedy Space Center in Florida to build a full-scale Crew Dragon model, or Recovery Trainer, that will be used by the U.S. Air Force to perform flight-like rescue and recovery training exercises in the open ocean later this year.

The model, shown above with astronauts Dan Burbank and Victor Glover inside, is built to mimic the Crew Dragon spacecraft that SpaceX is developing with NASA’s Commercial Crew Program to fly astronauts to and from the International Space Station. In certain unusual recovery situations, SpaceX may need to work with the U.S. Air Force to send parajumpers to recover astronauts from the capsule. The Recovery Trainer will be used by the Air Force to prepare procedures and train for this contingency scenario. The trainer also has two working hatches and other simulated components similar to the ones astronauts and support teams will encounter in real missions.

Scott Colloredo, deputy director of Kennedy’s Engineering Directorate, said the engineers adapted SpaceX designs of internal elements to be compatible with the trainer and worked with Kennedy’s Prototype Development Lab to produce the parts quickly and install them inside the trainer. The Prototype Development Lab designs, fabricates and tests prototypes, test articles and test support equipment. The lab has a long history of providing fast solutions to complex operations problems. The lab’s teams of engineers use specialized equipment to produce exacting, one-of-a-kind items made from a range of materials depending on the design.

“We perform things that complement what the partners and programs provide,” Colloredo said. “The team delivered right to the minute.”

SpaceX is now finalizing modifications to the trainer to ensure it floats in water in the same way as the Crew Dragon spacecraft. Following those modifications, the trainer will enter service as the primary training vehicle for Crew Dragon astronaut recovery operations.

https://blogs.nasa.gov/kennedy/2017/06/05/crew-dragon-trainer-takes-shape-at-kennedy/ (https://blogs.nasa.gov/kennedy/2017/06/05/crew-dragon-trainer-takes-shape-at-kennedy/)
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Comga on 06/15/2017 05:22 am
Noticed something. The nose cone is secured by the docking port latches, with the cone having simply a female ring. Very clever.

The hinge is better fleshed out.
The inside of the cap is mat instead of reflective, nearly specular.
The cowling around the IDA has sprouted a half dozen large holes, perhaps for drogue chutes or their mortars?
And is that supposed to be a forward window in the hatch behind the docking adapter?
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: TheKutKu on 07/16/2017 02:31 pm
Is it true that propulsive landings for Dragon v2 are off the table?
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: deruch on 07/16/2017 03:49 pm
Is it true that propulsive landings for Dragon v2 are off the table?
Per NASA request/requirement, the initial crew missions will land under parachutes and ergo be water landings.  CRS2 missions flown with Dragon 2s are expected to be used to prove out the propulsive landing technique to NASA's satisfaction before they eventually are allowed to use it for crew. 
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: yg1968 on 07/16/2017 04:01 pm
I don't believe that it is actually a NASA requirement. SpaceX likely decided that it would be easier to certify water landings for the first commercial crew flights given that propulsive landing has yet to be tested on an actual flight. A propulsive landing CRS2 flight is likely to happen prior to a crewed propulsive landing flight. 
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: rockets4life97 on 07/16/2017 05:06 pm
Is it true that propulsive landings for Dragon v2 are off the table?

The first humans to land propulsively in Dragon 2 will almost certainly be private citizens, not NASA astronauts. NASA is too risk averse to go first.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: dror on 07/16/2017 06:13 pm
Are they still planing on fast transfers for ISS like Soyuz?
And if so, are we going to see it implemented on Dragon 1 first like on the Progress? When?
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Chris Bergin on 07/16/2017 08:15 pm
Dragon 2 was always going to be chutes to start with:
https://www.nasaspaceflight.com/2014/08/dragon-v2-rely-parachutes-landing/

Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: uhuznaa on 07/16/2017 08:48 pm
Is it true that propulsive landings for Dragon v2 are off the table?

The first humans to land propulsively in Dragon 2 will almost certainly be private citizens, not NASA astronauts. NASA is too risk averse to go first.

Since NASA bought into the pusher LAS engines (same as landing engines) with the same fuel, they will have to take the risk then of smashing down into the water with a ton of hypergolics or so in the tanks at the bottom of the capsule. If then a tank ruptures or a valve gives way or a helium COPV blows apart they will get an ugly reddish fireball.

If they won't burn off or dump the propellants at some point before that, parachute landings will be MORE dangerous than propulsive landings. And even then dumping such amounts of highly corrosive propellants and dousing your vehicle in it before deploying your parachutes sounds like a bad idea. Apollo once had to land on two of three parachutes because the dumped RCS propellants ate some shroud lines and this was MUCH less than what Dragon 2 will have to dump.

Once you have committed to carrying such an awful lot of hypergols you better use them up by burning them through your engines before touching down. I really can't understand why not using and instead keep sitting on them should be safer by any measure. I have no idea what NASA and SpaceX will do here, but they would need to be crazy to splash down with all of this still in the tanks. At the very least they would have to vent the helium COPVs to not turn them into shrapnel bombs at splash-down and even then all the monomethylhydrazine and dinitrogen tetroxide would be a bomb waiting to go off at the slightest damage to a tank or valve or line. And this would not be a danger only to the crew, but also to the recovery crews and the ships.

This is one of the great mysteries to me with Dragon 2. Not going all the way to a propulsive landing here doesn't make anything easier or safer. It would be like using the ejection seat in a fighter jet at landings because you don't trust your landing gear.


Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: AbuSimbel on 07/16/2017 09:05 pm
Definitely not an expert, but would the splashdown be the most mechanically stressful phase of the mission for the COPVs and the associated structures? I'd think a failure should be as likely during ascent, if not more so. Is that the case?
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: deruch on 07/16/2017 09:35 pm
Dragon 2 was always going to be chutes to start with:
https://www.nasaspaceflight.com/2014/08/dragon-v2-rely-parachutes-landing/

Yes, but originally CCtCap included quite a bit of effort related to proving out propulsive landings for eventual use in (early?) operational missions.  Maybe with some polite disagreement between SpaceX and NASA as to how soon it could realistically be used.  Subsequently, much of that planned effort seems to have been downscaled or offloaded.  Potentially this is just because it was never intended as being on the critical path to certification.  So, since the program has been delayed and they are pushing as hard as possible to earliest delivery, non-essential work has been pared. 

SpaceX's Experimental Permit to launch DragonFly missions expires in 2 weeks (July 28th) and though they've had it for 2 years it's never yet flown.   :'(
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: rockets4life97 on 07/17/2017 12:06 am
Is it true that propulsive landings for Dragon v2 are off the table?

The first humans to land propulsively in Dragon 2 will almost certainly be private citizens, not NASA astronauts. NASA is too risk averse to go first.

Since NASA bought into the pusher LAS engines (same as landing engines) with the same fuel, they will have to take the risk then of smashing down into the water with a ton of hypergolics or so in the tanks at the bottom of the capsule. If then a tank ruptures or a valve gives way or a helium COPV blows apart they will get an ugly reddish fireball.

If they won't burn off or dump the propellants at some point before that, parachute landings will be MORE dangerous than propulsive landings. And even then dumping such amounts of highly corrosive propellants and dousing your vehicle in it before deploying your parachutes sounds like a bad idea. Apollo once had to land on two of three parachutes because the dumped RCS propellants ate some shroud lines and this was MUCH less than what Dragon 2 will have to dump.

Once you have committed to carrying such an awful lot of hypergols you better use them up by burning them through your engines before touching down. I really can't understand why not using and instead keep sitting on them should be safer by any measure. I have no idea what NASA and SpaceX will do here, but they would need to be crazy to splash down with all of this still in the tanks. At the very least they would have to vent the helium COPVs to not turn them into shrapnel bombs at splash-down and even then all the monomethylhydrazine and dinitrogen tetroxide would be a bomb waiting to go off at the slightest damage to a tank or valve or line. And this would not be a danger only to the crew, but also to the recovery crews and the ships.

This is one of the great mysteries to me with Dragon 2. Not going all the way to a propulsive landing here doesn't make anything easier or safer. It would be like using the ejection seat in a fighter jet at landings because you don't trust your landing gear.

My expectation is NASA will have SpaceX burn off the hypergol fuel before re-entry. It will be another event (like removing an LAS tower), but would be less risky then landing with the fuel as you say.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: matthewkantar on 07/17/2017 12:53 am
SpaceX's Experimental Permit to launch DragonFly missions expires in 2 weeks (July 28th) and though they've had it for 2 years it's never yet flown.   :'(

Do we know this for a fact? There was the video of the tether test, but wasn't that a leak, or at least an accidental release?

Matthew
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: old_sellsword on 07/17/2017 01:03 am
SpaceX's Experimental Permit to launch DragonFly missions expires in 2 weeks (July 28th) and though they've had it for 2 years it's never yet flown.   :'(

Do we know this for a fact? There was the video of the tether test, but wasn't that a leak, or at least an accidental release?

Matthew

Completely planned release.

https://youtu.be/07Pm8ZY0XJI
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: cppetrie on 07/17/2017 01:04 am
SpaceX's Experimental Permit to launch DragonFly missions expires in 2 weeks (July 28th) and though they've had it for 2 years it's never yet flown.   :'(

Do we know this for a fact? There was the video of the tether test, but wasn't that a leak, or at least an accidental release?

Matthew
Would the launch abort test have launched under this permit?
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: deruch on 07/17/2017 02:36 am
SpaceX's Experimental Permit to launch DragonFly missions expires in 2 weeks (July 28th) and though they've had it for 2 years it's never yet flown.   :'(

Do we know this for a fact? There was the video of the tether test, but wasn't that a leak, or at least an accidental release?
Yes.  No flights have been conducted under this permit.  In addition to the unlikelihood of any such having gone totally unknown/unobserved/unleaked by the rabid SpaceX stalking community, this is also verified by visiting the FAA's site tracking "permitted" launches where none are listed: https://www.faa.gov/data_research/commercial_space_data/launches/?type=permitted . 


Would the launch abort test have launched under this permit?
No.  The Pad Abort was under a license (https://www.faa.gov/data_research/commercial_space_data/launch_details/?id=1679), not a permit.  The Inflight abort will most likely also be under a license.  This referenced permit was specifically for DragonFly testing in McGreggor, TX. 
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: cscott on 07/17/2017 01:14 pm
Are they still planing on fast transfers for ISS like Soyuz?
And if so, are we going to see it implemented on Dragon 1 first like on the Progress? When?
Fast transfers will likely be used for crew. There is no technical limitation for dragon 1 or 2, but fast transfers require the ISS to use up propellant for the fast rendezvous, and it's not worth spending this precious resource on cargo missions.  So it's unlikely you'll ever see a fast rendezvous on a cargo mission, whether dragon 1 or 2.

I believe the only times Progress used fast rendezvous for cargo was back in 2012 when the capability was first being developed on the ISS side.  Now that the ISS procedures are established, there is no need to spend propellant on further testing of that sort.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Norm38 on 07/17/2017 01:24 pm
My expectation is NASA will have SpaceX burn off the hypergol fuel before re-entry. It will be another event (like removing an LAS tower), but would be less risky then landing with the fuel as you say.

What's the best use of the fuel if not for landings? Can they decelerate enough to take stress off the heat shield?
Or should they reboost ISS before undocking? Can D2 do reboosts?
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: envy887 on 07/17/2017 01:52 pm
My expectation is NASA will have SpaceX burn off the hypergol fuel before re-entry. It will be another event (like removing an LAS tower), but would be less risky then landing with the fuel as you say.

What's the best use of the fuel if not for landings? Can they decelerate enough to take stress off the heat shield?
Or should they reboost ISS before undocking? Can D2 do reboosts?

They could slow down enough to take the edge off for entry. Burning off all the hypergols through the SuperDracos should reduce peak heating by 30-40%. Reducing speed and dumping mass both help.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: starsilk on 07/17/2017 05:46 pm
Are they still planing on fast transfers for ISS like Soyuz?
And if so, are we going to see it implemented on Dragon 1 first like on the Progress? When?
Fast transfers will likely be used for crew. There is no technical limitation for dragon 1 or 2, but fast transfers require the ISS to use up propellant for the fast rendezvous, and it's not worth spending this precious resource on cargo missions.  So it's unlikely you'll ever see a fast rendezvous on a cargo mission, whether dragon 1 or 2.

I believe the only times Progress used fast rendezvous for cargo was back in 2012 when the capability was first being developed on the ISS side.  Now that the ISS procedures are established, there is no need to spend propellant on further testing of that sort.

is that actually true, given that Dragon 2 is going to have a huge amount of fuel on board available - if it's doing a splashdown landing.

I would think it could get to ISS fast without the ISS having to maneuver.. would also use up some of those nasty hypergols.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: uhuznaa on 07/17/2017 07:49 pm
My expectation is NASA will have SpaceX burn off the hypergol fuel before re-entry. It will be another event (like removing an LAS tower), but would be less risky then landing with the fuel as you say.

What's the best use of the fuel if not for landings? Can they decelerate enough to take stress off the heat shield?
Or should they reboost ISS before undocking? Can D2 do reboosts?

They could slow down enough to take the edge off for entry. Burning off all the hypergols through the SuperDracos should reduce peak heating by 30-40%. Reducing speed and dumping mass both help.

Burning the propellants before reentry will move the CoG quite a lot, so it will be in a very different configuration for reentry depending on doing a splash-down or going for a propulsive landing then. According to the FAA docs this is 1,388 kg of propellants, in tanks at the very bottom of the capsule. Either you design your capsule with that kind of ballast or without it, but making it fit for both would be a stretch, I'd say.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Jim on 07/17/2017 07:59 pm

I would think it could get to ISS fast without the ISS having to maneuver.. would also use up some of those nasty hypergols.

Launch provides the fast ascent and not so much maneuvering propellant.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: dror on 07/17/2017 08:26 pm
My expectation is NASA will have SpaceX burn off the hypergol fuel before re-entry. It will be another event (like removing an LAS tower), but would be less risky then landing with the fuel as you say.

What's the best use of the fuel if not for landings? Can they decelerate enough to take stress off the heat shield?
Or should they reboost ISS before undocking? Can D2 do reboosts?
This may be a silli question,
Can it be designed to transfer the access fuel to the ISS?
I mean, apart from the effect on the Dragon's CoG
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: starsilk on 07/17/2017 08:46 pm

I would think it could get to ISS fast without the ISS having to maneuver.. would also use up some of those nasty hypergols.

Launch provides the fast ascent and not so much maneuvering propellant.

seems like plentiful maneuvering propellant should make it possible to overcome an uncooperative target.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: tater on 07/17/2017 09:08 pm
I think I would have the crew spacecraft monitor parachute deployment, and if there were to be an unsurvivable parachute failure, then it propulsively lands in the ocean. The best use would be to protect the crew if at all possible, no?

(obviously it would have to be programmed for that as a possible contingency)
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Jim on 07/18/2017 01:34 am
My expectation is NASA will have SpaceX burn off the hypergol fuel before re-entry. It will be another event (like removing an LAS tower), but would be less risky then landing with the fuel as you say.

What's the best use of the fuel if not for landings? Can they decelerate enough to take stress off the heat shield?
Or should they reboost ISS before undocking? Can D2 do reboosts?
This may be a silli question,
Can it be designed to transfer the access fuel to the ISS?
I mean, apart from the effect on the Dragon's CoG


no, it would have to dock to the russian segment for that
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Jim on 07/18/2017 01:36 am

seems like plentiful maneuvering propellant should make it possible to overcome an uncooperative target.

It has nothing to do with uncooperative target.  And there is a limit to what propellant can do. 
Like I said, fast ascent is a launch targeting issue and not maneuvering propellant
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Norm38 on 07/18/2017 01:56 am
Jim,
It was mentioned earlier that ISS itself has to maneuver to support a fast rendezvous. Is that not true? If it is, isn't it more efficient for the smaller visiting vehicle to maneuver than the ISS?
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: starsilk on 07/18/2017 04:09 am

seems like plentiful maneuvering propellant should make it possible to overcome an uncooperative target.

It has nothing to do with uncooperative target.  And there is a limit to what propellant can do. 
Like I said, fast ascent is a launch targeting issue and not maneuvering propellant
Uncooperative = political games.

There's a limit to what propellant can do? That's an odd statement. A lot of propellant can do all sorts of things in orbit... And dragon 2 will have a LOT to burn off.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Comga on 07/18/2017 05:41 am
A question I could answer myself if I had enough time to program the equations:
If a Dragon in a circular orbit about the altitude of the ISS used all of its maneuvering fuel to enter an elliptical orbit, by how much could it increase its orbital period?  What's the max delta-V?
In reverse, this is the maximum phasing per orbit that could be utilized by a Dragon boosted by the second stage into an orbit with an apogee above the ISS. (Which is limited by the rocket performance.  Not sure how that would be calculated.)
This would be an inverted version of a normal launch to the ISS where the arriving ship "catches up" from below and behind" only it wouldn't be limited by the atmosphere.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: soltasto on 07/18/2017 09:32 am
My expectation is NASA will have SpaceX burn off the hypergol fuel before re-entry. It will be another event (like removing an LAS tower), but would be less risky then landing with the fuel as you say.

What's the best use of the fuel if not for landings? Can they decelerate enough to take stress off the heat shield?
Or should they reboost ISS before undocking? Can D2 do reboosts?
This may be a silli question,
Can it be designed to transfer the access fuel to the ISS?
I mean, apart from the effect on the Dragon's CoG


no, it would have to dock to the russian segment for that

I theory a revision to the International docking standard and a subsequent upgrade to the ISS US segment docking adapters could allow for water, fuel, oxidizer and pressurant transfer.

This kind of transfer is currently "reserved" from sections 3.4.2 to 3.4.5 in the official document attached below

International Docking System Standard
(IDSS)
Interface Definition Document (IDD)
Revision E
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Jim on 07/18/2017 02:37 pm

There's a limit to what propellant can do? That's an odd statement. A lot of propellant can do all sorts of things in orbit... And dragon 2 will have a LOT to burn off.

 Not really "a lot" in the true scheme of thing. 

Not when the spacecraft has limited orbital life. 


Uncooperative = political games.


And wrong about that.  ISS maneuvering means more propellant has to be brought up.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Jim on 07/18/2017 02:39 pm
revision to the International docking standard and a subsequent upgrade to the ISS US segment docking adapters could allow for water, fuel, oxidizer and pressurant transfer.


Not feasible to plumb the ISS US segment for el, oxidizer and pressurant transfer.  It would still have to go to the Russian segment.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Jim on 07/18/2017 02:49 pm
Jeesh, doe this have to be explained again.  The two day transfer to the ISS allows for daily launch windows.  The fast transfer does not and the amount of spacecraft propellant has limited affect on this.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: starsilk on 07/18/2017 03:35 pm

There's a limit to what propellant can do? That's an odd statement. A lot of propellant can do all sorts of things in orbit... And dragon 2 will have a LOT to burn off.

 Not really "a lot" in the true scheme of thing. 

random internet speculators out there say 400-450 m/s. that seems like a lot.


Not when the spacecraft has limited orbital life. 

superdracos can apply all of that in < 10 seconds. not that they would want to, but there will be more than enough capability to apply the delta-v quickly.


Uncooperative = political games.


And wrong about that.  ISS maneuvering means more propellant has to be brought up.

which means money needs to be paid for fuel supply. which means political games.

far, far simpler for the spacecraft to do it than the space station.

ah well, instead they can take all that dangerous fuel to the ISS for 6 months. then do the world's largest re-entry burn instead.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: JasonAW3 on 07/18/2017 03:49 pm
revision to the International docking standard and a subsequent upgrade to the ISS US segment docking adapters could allow for water, fuel, oxidizer and pressurant transfer.


Not feasible to plumb the ISS US segment for el, oxidizer and pressurant transfer.  It would still have to go to the Russian segment.

Jim, wasn't there some discussion about an interim propulsion module a couple of years back, when Russia was considering pulling their segment of the ISS out to form their own space station complex?
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Lars-J on 07/18/2017 04:26 pm
revision to the International docking standard and a subsequent upgrade to the ISS US segment docking adapters could allow for water, fuel, oxidizer and pressurant transfer.


Not feasible to plumb the ISS US segment for el, oxidizer and pressurant transfer.  It would still have to go to the Russian segment.

Jim, wasn't there some discussion about an interim propulsion module a couple of years back, when Russia was considering pulling their segment of the ISS out to form their own space station complex?

There were several variants proposed: https://en.wikipedia.org/wiki/ISS_Propulsion_Module

But none of them would use propellant transfer. It would have been an expendable stop gap module, and it was more of a back-up plan if Zvezda failed to launch.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Jim on 07/18/2017 04:35 pm

random internet speculators out there say 400-450 m/s. that seems like a lot.

superdracos can apply all of that in < 10 seconds. not that they would want to, but there will be more than enough capability to apply the delta-v quickly.


Neither are going to make rendezvous quicker.

If the Dragon is not launched at the proper time, it will take many more days for it to catch up with the ISS. 

2 day rendezvous provides for launch opportunities every 24 hours - 23 minutes.

Fast transfer does not allow for 24hr scrub turnaround, the next opportunity is too soon and a day will have to be skipped.

The amount of Dragon propellant does not change this.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Basto on 07/18/2017 05:51 pm

random internet speculators out there say 400-450 m/s. that seems like a lot.

superdracos can apply all of that in < 10 seconds. not that they would want to, but there will be more than enough capability to apply the delta-v quickly.


Neither are going to make rendezvous quicker.

If the Dragon is not launched at the proper time, it will take many more days for it to catch up with the ISS. 

2 day rendezvous provides for launch opportunities every 24 hours - 23 minutes.

Fast transfer does not allow for 24hr scrub turnaround, the next opportunity is too soon and a day will have to be skipped.

The amount of Dragon propellant does not change this.

I believe the disconnect here is people are misunderstanding what a "rapid" ISS rendezvous actually entails. It does not mean that the vehicle is actually traveling toward the ISS at a higher velocity. It just means you launch when the launch site is in the same plane AND ISS is at a specific angular distance to the launch site. Which means fewer launch windows.

I am pretty sure we do not want objects approaching the ISS for rendezvous with a velocity differential of 400+ M/S.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: LouScheffer on 07/18/2017 05:51 pm

random internet speculators out there say 400-450 m/s. that seems like a lot.

superdracos can apply all of that in < 10 seconds. not that they would want to, but there will be more than enough capability to apply the delta-v quickly.


Neither are going to make rendezvous quicker.

If the Dragon is not launched at the proper time, it will take many more days for it to catch up with the ISS. 

2 day rendezvous provides for launch opportunities every 24 hours - 23 minutes.

Fast transfer does not allow for 24hr scrub turnaround, the next opportunity is too soon and a day will have to be skipped.

The amount of Dragon propellant does not change this.
This is true with the current method of fast rendezvous, where you adjust the phase of ISS so it's in the right place when you launch in-plane.

But a different approach is certainly possible.  You launch when the ISS *phase* is right, then you do a plane correction to get into the ISS plane.   This is the approach used on  Gemini 11 (https://nssdc.gsfc.nasa.gov/nmc/spacecraftDisplay.do?id=1966-081A), which achieved a 1.5 hour rendezvous.  Compared to the existing approach, this needs additional delta-V, to be provided by some combination of excess booster performance and payload maneuvering.  With this approach you get two opportunities each day.

Falcon 9 easily has enough raw performance to do this, if run expendable.  But if the booster does RTLS, then the margin is less and the booster may not be able to do all of the plane change needed.  In this case the amount of Dragon propellant may determine if this approach is possible.

This seems pretty unlikely, though. It's a  very different procedure, SpaceX does not currently offer  yaw steering, two day rendezvous for cargo seems fine, phasing for crewed missions only is not too much of  burden, and so on.

Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: starsilk on 07/18/2017 06:02 pm

random internet speculators out there say 400-450 m/s. that seems like a lot.

superdracos can apply all of that in < 10 seconds. not that they would want to, but there will be more than enough capability to apply the delta-v quickly.


Neither are going to make rendezvous quicker.

If the Dragon is not launched at the proper time, it will take many more days for it to catch up with the ISS. 

2 day rendezvous provides for launch opportunities every 24 hours - 23 minutes.

Fast transfer does not allow for 24hr scrub turnaround, the next opportunity is too soon and a day will have to be skipped.

The amount of Dragon propellant does not change this.
This is true with the current method of fast rendezvous, where you adjust the phase of ISS so it's in the right place when you launch in-plane.

But a different approach is certainly possible.  You launch when the ISS *phase* is right, then you do a plane correction to get into the ISS plane.   This is the approach used on  Gemini 11 (https://nssdc.gsfc.nasa.gov/nmc/spacecraftDisplay.do?id=1966-081A), which achieved a 1.5 hour rendezvous.  Compared to the existing approach, this needs additional delta-V, to be provided by some combination of excess booster performance and payload maneuvering.  With this approach you get two opportunities each day.

Falcon 9 easily has enough raw performance to do this, if run expendable.  But if the booster does RTLS, then the margin is less and the booster may not be able to do all of the plane change needed.  In this case the amount of Dragon propellant may determine if this approach is possible.

This seems pretty unlikely, though. It's a  very different procedure, SpaceX does not currently offer  yaw steering, two day rendezvous for cargo seems fine, phasing for crewed missions only is not too much of  burden, and so on.

seems like a useful technology to (re) develop.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: dror on 07/18/2017 06:11 pm
My expectation is NASA will have SpaceX burn off the hypergol fuel before re-entry. It will be another event (like removing an LAS tower), but would be less risky then landing with the fuel as you say.

What's the best use of the fuel if not for landings? Can they decelerate enough to take stress off the heat shield?
Or should they reboost ISS before undocking? Can D2 do reboosts?
This may be a silli question,
Can it be designed to transfer the access fuel to the ISS?
I mean, apart from the effect on the Dragon's CoG


no, it would have to dock to the russian segment for that

Not that I think it will or should happen, but can it be manipulated to the russian segment for the fuel transfer duration?
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Owlon on 07/18/2017 06:47 pm
My expectation is NASA will have SpaceX burn off the hypergol fuel before re-entry. It will be another event (like removing an LAS tower), but would be less risky then landing with the fuel as you say.

What's the best use of the fuel if not for landings? Can they decelerate enough to take stress off the heat shield?
Or should they reboost ISS before undocking? Can D2 do reboosts?
This may be a silli question,
Can it be designed to transfer the access fuel to the ISS?
I mean, apart from the effect on the Dragon's CoG


no, it would have to dock to the russian segment for that

Not that I think it will or should happen, but can it be manipulated to the russian segment for the fuel transfer duration?

The US and Russian segments have different docking adapters, so Dragon cannot attach as is.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Jim on 07/18/2017 06:48 pm
But a different approach is certainly possible.  You launch when the ISS *phase* is right, then you do a plane correction to get into the ISS plane.   This is the approach used on  Gemini 11 (https://nssdc.gsfc.nasa.gov/nmc/spacecraftDisplay.do?id=1966-081A), which achieved a 1.5 hour rendezvous.  Compared to the existing approach, this needs additional delta-V, to be provided by some combination of excess booster performance and payload maneuvering.  With this approach you get two opportunities each day.

Falcon 9 easily has enough raw performance to do this, if run expendable.  But if the booster does RTLS, then the margin is less and the booster may not be able to do all of the plane change needed.  In this case the amount of Dragon propellant may determine if this approach is possible.

This seems pretty unlikely, though. It's a  very different procedure, SpaceX does not currently offer  yaw steering, two day rendezvous for cargo seems fine, phasing for crewed missions only is not too much of  burden, and so on.


there are other opportunities per day with the other methods but when you select one, operational constraints eliminate the other opportunities.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Jim on 07/18/2017 06:57 pm

seems like a useful technology to (re) develop.

Nothing has to be developed.  It is exists but there are other constraints that prevent it from happening.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: abaddon on 07/18/2017 08:25 pm
there are other opportunities per day with the other methods but when you select one, operational constraints eliminate the other opportunities.
Would those constraints be stuff like "don't dock during station night when the astronauts are sleeping" type stuff, for example?
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: starsilk on 07/18/2017 09:21 pm

seems like a useful technology to (re) develop.

Nothing has to be developed.  It is exists but there are other constraints that prevent it from happening.

if we could do it in 1966, I'm sure today's operational constraints could be figured out.... assuming of course they are not "it's too risky" or "politics".

at least we have moved on from "it's not possible" to "operational constraints".

without knowing what those constraints are, it's hard to tell.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: LouScheffer on 07/18/2017 10:47 pm

seems like a useful technology to (re) develop.

Nothing has to be developed.  It is exists but there are other constraints that prevent it from happening.
I suspect that with Atlas-Cygnus combination, you could do this with completely off the shelf hardware, just by buying a bigger Atlas.  Atlas already does yaw steering, and can already handle plus or minus 15 minutes from the optimal time.  Increase this to 45 minutes, and you've got it, since the worst case is that ISS is precisely between two orbital tracks as measured at the launch site, and passes are about 90 minutes apart.

So the technology is already there.  But you'd need to qualify the Cygnus for the new booster configuration and profile, develop new software, practice the associated procedures, and most importantly shell out a few tens of millions for another solid booster or two.   All this for a capability for which there is no pressing need, so why bother?

For SpaceX to do this, in addition to the software and procedure changes, they would need to add yaw steering to the booster.  (If you try to do it all with the capsule, you could need as much as 1300 m/s, which is too much.  It's much more efficient to do during the boost stage.)    On the other hand the performance is likely there already.  Worst case you might have to switch to a downrange landing of the booster.  But again, why bother?
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Lars-J on 07/18/2017 10:58 pm
For SpaceX to do this, in addition to the software and procedure changes, they would need to add yaw steering to the booster.  (If you try to do it all with the capsule, you could need as much as 1300 m/s, which is too much.  It's much more efficient to do during the boost stage.)    On the other hand the performance is likely there already.  Worst case you might have to switch to a downrange landing of the booster.  But again, why bother?

Yaw steering is purely a software added capability - the F9 hardware is capable of it. (no additional gimbal ability is required) The performance hit would likely be pretty small.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Jim on 07/18/2017 10:59 pm

seems like a useful technology to (re) develop.

Nothing has to be developed.  It is exists but there are other constraints that prevent it from happening.

if we could do it in 1966, I'm sure today's operational constraints could be figured out.... assuming of course they are not "it's too risky" or "politics".

at least we have moved on from "it's not possible" to "operational constraints".

without knowing what those constraints are, it's hard to tell.

No. Just stop with it.  You make it sound like everything is artificial.  Never said it was impossible
A. The big reason is that it doesn't allow for 24 hr scrub turnaround.  That can't be changed.  The choice is to be able to launch the next day after a scrub vs a shorter time to rendezvous.  That is what I have been pointing out for many posts.

B. Falcon doesn't do yaw steering. 

C.  And again, the amount of Dragon propellant does not enter the picture
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Jim on 07/18/2017 11:02 pm
For SpaceX to do this, in addition to the software and procedure changes, they would need to add yaw steering to the booster.  (If you try to do it all with the capsule, you could need as much as 1300 m/s, which is too much.  It's much more efficient to do during the boost stage.)    On the other hand the performance is likely there already.  Worst case you might have to switch to a downrange landing of the booster.  But again, why bother?

Yaw steering is purely a software added capability - the F9 hardware is capable of it. (no additional gimbal ability is required) The performance hit would likely be pretty small.

It is more than just "software". Trajectory design and implementation. It calls for process changes
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: LouScheffer on 07/18/2017 11:46 pm

A. The big reason is that it doesn't allow for 24 hr scrub turnaround.  That can't be changed.  The choice is to be able to launch the next day after a scrub vs a shorter time to rendezvous.  That is what I have been pointing out for many posts.

C.  And again, the amount of Dragon propellant does not enter the picture
Not sure I understand this.   It's true the current method (adjusting ISS phase) requires a 2 day turnaround.  That's because ISS makes about 15.5 orbits in a day.  So if you have an opportunity, and you can't launch, then one day later, ISS has made 15.5 orbits and is in (exactly) the wrong spot when the plane is again right.  One more day later it's made 31 orbits and is back in the right place.  In this case more delta-V from the chaser does not help, you just need to wait.

But rendezvous by plane change allows both daily opportunities AND fast rendezvous.  In theory you get two opportunities per day, but most (all?) ranges can only support one of ascending or descending nodes, due to ground track constraints.  So you launch when the phase is right, on the pass with the right ascending or descending, and the closest plane.  This happens once per day.  The actual delta-V will change daily, but is never worse than 45 minutes worth.  If you don't have enough delta-V for the worst case you may need to wait a day (you can't get the worst case every day because of the 15.5 orbit/day condition).   Here, if the available delta-V from the booster is insufficient for the worst case, the amount of fuel carried by the Dragon might make the difference between launching and waiting an extra day for an easier opportunity.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Joffan on 07/19/2017 12:47 am
A question I could answer myself if I had enough time to program the equations:
If a Dragon in a circular orbit about the altitude of the ISS used all of its maneuvering fuel to enter an elliptical orbit, by how much could it increase its orbital period?  What's the max delta-V?
In reverse, this is the maximum phasing per orbit that could be utilized by a Dragon boosted by the second stage into an orbit with an apogee above the ISS. (Which is limited by the rocket performance.  Not sure how that would be calculated.)
This would be an inverted version of a normal launch to the ISS where the arriving ship "catches up" from below and behind" only it wouldn't be limited by the atmosphere.

Unfortunately if you want to stay out of the inner Van Allen belt you might need to limit the apogee to 1000km altitude or so. With a circular orbit at that height you'd back up to the ISS at about 12 minutes per orbit; with perigee at 400km, only about 6 minutes per orbit. The approximate rule for the ISS is that 100km altitude difference (circular orbit) makes about 2 min difference to the orbital period.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: yokem55 on 07/19/2017 09:43 pm
I wonder if they have any contingency plans for a crew access tower at LC-40 in the event of FH having a bad day on the pad. It would suck to have to design and build one, but I'm thinking it would surely be needed to keep a mid 2018 crewed demo flight if 39a gets severely damaged.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: whitelancer64 on 07/19/2017 10:10 pm
I wonder if they have any contingency plans for a crew access tower at LC-40 in the event of FH having a bad day on the pad. It would suck to have to design and build one, but I'm thinking it would surely be needed to keep a mid 2018 crewed demo flight if 39a gets severely damaged.

I doubt it. It would be a major, major undertaking, in any case, to build a launch tower at SLC-40. Pre-planning might save some time, but not much in the long run.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: yg1968 on 07/20/2017 02:40 am
I am disappointed that SpaceX seems to have given up on landing Dragon2 on land. If Soyuz and CST-100 can do it, why can't Dragon2 also do it?
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Robotbeat on 07/20/2017 03:05 am
I am disappointed that SpaceX seems to have given up on landing Dragon2 on land. If Soyuz and CST-100 can do it, why can't Dragon2 also do it?
Both of those drop their heatshield before landing, for one.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: yg1968 on 07/20/2017 03:20 am
I am disappointed that SpaceX seems to have given up on landing Dragon2 on land. If Soyuz and CST-100 can do it, why can't Dragon2 also do it?
Both of those drop their heatshield before landing, for one.

Soyuz doesn't have legs as far as I know. Are they absolutely necessary for Dragon2 land landing?
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: GWH on 07/20/2017 03:25 am
Doesn't matter the Soyuz won't be reused.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Scylla on 07/20/2017 04:08 am
Elon has only one goal...Mars. Everything SpaceX does, in some way, supports the achievement of this goal.

Propulsive landing of Dragon 2 supported the architecture of getting to Mars.

The archetecture has evolved and propulsive landing of Dragon 2 no longer supports getting to Mars.

Elon could continue working for Dragon 2 propulsive landing, but he's not going to waste time and money on something that no longer serves the goal...Mars.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: woods170 on 07/20/2017 07:08 am
I am disappointed that SpaceX seems to have given up on landing Dragon2 on land. If Soyuz and CST-100 can do it, why can't Dragon2 also do it?
Both of those drop their heatshield before landing, for one.
Additionally: Crew Dragon (aka Dragon 2) is a temporary spacecraft. It will be in use for the run of ISS and the odd tourist mission. But that's it. Crew Dragon does not get people to Mars. So, beyond ISS and circumlunar there won't be Crew Dragon. Then add in that NASA is not certifying Crew Dragon for re-use and the main arguments for landing on land (no salt water intrusion, no extensive refurbishment, no extensive re-certification for flight) go away.
Next, add in that SpaceX has extensive experience with open-ocean recovery of capsules and it becomes a given that Crew Dragon will always land in water.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: tea monster on 07/20/2017 11:16 am
Also, the ability of Dragon 2 to land on her jets allowed her to set down nearly anywhere in the solar system where there was a solid surface. I was looking forward to the series of Red Dragon missions, which would hopefully be followed by Titan Dragons, Europa Dragons, etc. etc. .
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: woods170 on 07/20/2017 11:55 am
Also, the ability of Dragon 2 to land on her jets allowed her to set down nearly anywhere in the solar system where there was a solid surface. I was looking forward to the series of Red Dragon missions, which would hopefully be followed by Titan Dragons, Europa Dragons, etc. etc. .
Remember the animation from the ITS reveal last year? It had ITS on Titan, ITS on Europa, etc. etc. You don't develop two planetary lander systems when you can make-do with one. Particularly when the newer system is better suited to do the job.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: high road on 07/20/2017 12:36 pm
I am disappointed that SpaceX seems to have given up on landing Dragon2 on land. If Soyuz and CST-100 can do it, why can't Dragon2 also do it?
Both of those drop their heatshield before landing, for one.
Additionally: Crew Dragon (aka Dragon 2) is a temporary spacecraft. It will be in use for the run of ISS and the odd tourist mission. But that's it. Crew Dragon does not get people to Mars. So, beyond ISS and circumlunar there won't be Crew Dragon. Then add in that NASA is not certifying Crew Dragon for re-use and the main arguments for landing on land (no salt water intrusion, no extensive refurbishment, no extensive re-certification for flight) go away.
Next, add in that SpaceX has extensive experience with open-ocean recovery of capsules and it becomes a given that Crew Dragon will always land in water.

So, no commercial space station in need of crew and supplies then?
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: rockets4life97 on 07/20/2017 01:20 pm
So, no commercial space station in need of crew and supplies then?

I think SpaceX would be happy to supply a future commercial station with crew and cargo. I doubt they banking on that market evolving though to fund their Mars plans. If it emerges, great. If not, then too bad. They'll be happy to keep flying Dragons as long as there is a paying customer. They might even upgrade Dragon (e.g. propulsive landing!) if someone wants to pay for that capability.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: yg1968 on 07/20/2017 01:50 pm
I am disappointed that SpaceX seems to have given up on landing Dragon2 on land. If Soyuz and CST-100 can do it, why can't Dragon2 also do it?
Both of those drop their heatshield before landing, for one.
Additionally: Crew Dragon (aka Dragon 2) is a temporary spacecraft. It will be in use for the run of ISS and the odd tourist mission. But that's it. Crew Dragon does not get people to Mars. So, beyond ISS and circumlunar there won't be Crew Dragon. Then add in that NASA is not certifying Crew Dragon for re-use and the main arguments for landing on land (no salt water intrusion, no extensive refurbishment, no extensive re-certification for flight) go away.
Next, add in that SpaceX has extensive experience with open-ocean recovery of capsules and it becomes a given that Crew Dragon will always land in water.

I am skeptical about BFR happenning anytime soon. But the good news is that SpaceX is now talking about the Moon. If the BFR second stage/spacecraft can land on the Moon, there may be a market there.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: uhuznaa on 07/20/2017 02:40 pm
I am disappointed that SpaceX seems to have given up on landing Dragon2 on land. If Soyuz and CST-100 can do it, why can't Dragon2 also do it?
Both of those drop their heatshield before landing, for one.
Additionally: Crew Dragon (aka Dragon 2) is a temporary spacecraft. It will be in use for the run of ISS and the odd tourist mission. But that's it. Crew Dragon does not get people to Mars. So, beyond ISS and circumlunar there won't be Crew Dragon. Then add in that NASA is not certifying Crew Dragon for re-use and the main arguments for landing on land (no salt water intrusion, no extensive refurbishment, no extensive re-certification for flight) go away.
Next, add in that SpaceX has extensive experience with open-ocean recovery of capsules and it becomes a given that Crew Dragon will always land in water.

I am skeptical about BFR happenning anytime soon. But the good news is that SpaceX is now talking about the Moon. If the BFR second stage/spacecraft can land on the Moon, there may be a market there.

A NASA market, yes. Another (and probably longer-term) market would be to use it as a cheap, fully  and rapidly reusable launcher to LEO. Falcon 9 and Heavy stop being cheap if you need to launch often and somewhat bigger payloads resulting in no reusability for the second stage (huge payload penalty).

Moon landings would mean refueling in orbit and probably on the Moon for the return leg, with all the lunar resource infrastructure coming with that. I do not see anyone in that market except (maybe) NASA after SLS being dead and buried and the usual suspects in old space being weened off of their gravy. I'm not holding my breath here...

But EM is sane enough to see that for his Mars goals he will need to make money with everything that comes along. We also will see fierce LEO competition with Blue Origin now by the way.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: envy887 on 07/20/2017 03:02 pm
A NASA market, yes. Another (and probably longer-term) market would be to use it as a cheap, fully  and rapidly reusable launcher to LEO. Falcon 9 and Heavy stop being cheap if you need to launch often and somewhat bigger payloads resulting in no reusability for the second stage (huge payload penalty).

Moon landings would mean refueling in orbit and probably on the Moon for the return leg, with all the lunar resource infrastructure coming with that. I do not see anyone in that market except (maybe) NASA after SLS being dead and buried and the usual suspects in old space being weened off of their gravy. I'm not holding my breath here...

But EM is sane enough to see that for his Mars goals he will need to make money with everything that comes along. We also will see fierce LEO competition with Blue Origin now by the way.

There will be a huge tourist market for the moon, if the price point is low enough. Even at insanely high prices there is some market just for flybys. I don't think Dragon or F9 will get near that price point, but the next gen vehicles may.

Refueling in lunar orbit on the return leg is most efficient for landings, at least until lunar refueling infrastructure exists (could be fuel or just oxidizer).
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Confusador on 07/20/2017 04:13 pm
Also, the ability of Dragon 2 to land on her jets allowed her to set down nearly anywhere in the solar system where there was a solid surface. I was looking forward to the series of Red Dragon missions, which would hopefully be followed by Titan Dragons, Europa Dragons, etc. etc. .
Remember the animation from the ITS reveal last year? It had ITS on Titan, ITS on Europa, etc. etc. You don't develop two planetary lander systems when you can make-do with one. Particularly when the newer system is better suited to do the job.

You're trading more capabilities for longer time before you can start.  By your logic, they won't ever go interplanetary with ITS, because by the time they get close they'll have plans for something better.  I'm personally sad that they weren't able to work through the issues with propulsively landing Dragon because landing in water is going to make refurbishment more expensive, which is going to slow down growth of secondary markets for crew transportation.

At the same time, I respect SpaceX for not getting stuck in sunk costs, and being willing to change plans when they don't work.  That strategy eventually worked for booster landing, and hopefully will eventually work for crew.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Space Ghost 1962 on 07/20/2017 04:57 pm
Suggest that after they did booster landing, and began to wrestle with reusable US again, landing capsules like Dragon no longer looked like wise investments.

With the propulsion of Raptor they are in another league entirely. Once you start playing in that league, you've maxed out chemical propulsion, and you want to get places with it fast.

They don't want to wait for Dragon or BFR/BFS. Need something "in between".

Even the Moon now looks good.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: craiglv2 on 07/20/2017 05:03 pm
I too, am sad that they weren't able to work through the issues with propulsive landing Dragon.  I feared this may be the case when we saw that the Dragon abort test kept the trunk attached and still wasn't terribly stable.  Also, the lack of any additional hover test videos, after the one short tethered video last year, led me to believe that there may be stability issues.  We all recall the multiple videos of the Falcon hover and landing tests, but not so for any Dragon hover tests.  Just my thoughts.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: envy887 on 07/20/2017 05:13 pm
I too, am sad that they weren't able to work through the issues with propulsive landing Dragon.  I feared this may be the case when we saw that the Dragon abort test kept the trunk attached and still wasn't terribly stable.  Also, the lack of any additional hover test videos, after the one short tethered video last year, led me to believe that there may be stability issues.  We all recall the multiple videos of the Falcon hover and landing tests, but not so for any Dragon hover tests.  Just my thoughts.

Dragon did a hover test:

https://www.youtube.com/watch?v=07Pm8ZY0XJI

And the trunk was supposed to stay attached during the pad abort test; that's how Dragon is aerodynamically stabilized during forward flight. Once the trunk is dropped, Dragon is supposed to rotate passively to a heat-shield forward orientation, which it did.

https://www.youtube.com/watch?v=1_FXVjf46T8
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: rsdavis9 on 07/20/2017 07:33 pm
I think the problem wasn't with the tech. They proved to themselves all the tech works. The problem was with nasa and all the hoops they would have had to jump through.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Norm38 on 07/20/2017 08:03 pm
So is the consensus now that Dragon2 is more of a temporary vehicle?  That it will only be used until the new Raptor based ship is ready? And then all usage shifts to that?
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Jim on 07/20/2017 08:06 pm
I think the problem wasn't with the tech. They proved to themselves all the tech works. The problem was with nasa and all the hoops they would have had to jump through.

No, they were not finished qualifying for themselves
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Negan on 07/20/2017 08:09 pm
So is the consensus now that Dragon2 is more of a temporary vehicle?  That it will only be used until the new Raptor based ship is ready? And then all usage shifts to that?

Not until there's another human rated, NASA certified spacecraft to take its place.

Edit: IMO that certification is going to be worth its wait in gold if orbital tourism or private stations ever happen.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: mme on 07/20/2017 08:09 pm
I think the problem wasn't with the tech. They proved to themselves all the tech works. The problem was with nasa and all the hoops they would have had to jump through.
I don't think we have proof that NASA wanted unreasonable hoop jumping.  After all, at one point NASA said they were OK with trying propulsive landing of cargo.  For all we know, SpaceX decided it was too hard with the current design and/or just not worth it.

(Sorry, it's a pet peeve of mine that many people assume that government-agency-X or regulation-Y is *always* the problem and then that becomes the "common knowledge" even though it is derived from the epistemological equivalent of "people are saying.")
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: envy887 on 07/20/2017 08:12 pm
I think the problem wasn't with the tech. They proved to themselves all the tech works. The problem was with nasa and all the hoops they would have had to jump through.

No, they were not finished qualifying for themselves

Only if NASA accepts propulsive landing risks, because BFS probably won't have parachutes at all.

It will have the advantage of lots of cargo landings for reliability evaluation before anyone flies on it.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Negan on 07/20/2017 08:43 pm
Only if NASA accepts propulsive landing risks, because BFS probably won't have parachutes at all.

It will have the advantage of lots of cargo landings for reliability evaluation before anyone flies on it.

But what if NASA never accepts propulsive landing on earth? Wouldn't this be a plus for SLS, DST, and Orion and a blow to the ITS architecture?
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Toast on 07/20/2017 08:50 pm
Only if NASA accepts propulsive landing risks, because BFS probably won't have parachutes at all.

It will have the advantage of lots of cargo landings for reliability evaluation before anyone flies on it.

But what if NASA never accepts propulsive landing on earth? Wouldn't this be a plus for SLS, DST, and Orion and a blow to the ITS architecture?

Unless NASA is paying for or flying on ITS, they don't really have any jurisdiction to say what SpaceX can or can't do. I think that would fall to the FAA.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Jim on 07/20/2017 08:51 pm
Only if NASA accepts propulsive landing risks, because BFS probably won't have parachutes at all.

It will have the advantage of lots of cargo landings for reliability evaluation before anyone flies on it.

But what if NASA never accepts propulsive landing on earth? Wouldn't this be a plus for SLS, DST, and Orion and a blow to the ITS architecture?

Who says NASA has a problem with propulsive landing?

https://www.youtube.com/watch?v=ju0Q6TWMYHw
https://www.youtube.com/watch?v=k_OD2V6fMLQ
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: rockets4life97 on 07/20/2017 08:52 pm
Who says NASA has a problem with propulsive landing?

Humans, Jim. The question is propulsive landing and humans...
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: abaddon on 07/20/2017 08:52 pm
Those are strange comparisons, as one was unmanned, and the other ... well, I'd hate to try landing on the Moon non-propulsively...
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Jim on 07/20/2017 08:53 pm
Who says NASA has a problem with propulsive landing?

Humans, Jim. The question is propulsive landing and humans...
https://www.youtube.com/watch?v=k_OD2V6fMLQ
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Jim on 07/20/2017 08:54 pm
Those are strange comparisons, as one was unmanned, and the other ... well, I'd hate to try landing on the Moon non-propulsively...

The point is that if it is properly qualified, there is no issue.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Negan on 07/20/2017 08:57 pm
Those are strange comparisons, as one was unmanned, and the other ... well, I'd hate to try landing on the Moon non-propulsively...

The point is that if it is properly qualified, there is no issue.

Are you saying the risk level NASA was willing to accept for Apollo is the same as today?
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: envy887 on 07/20/2017 08:57 pm
Only if NASA accepts propulsive landing risks, because BFS probably won't have parachutes at all.

It will have the advantage of lots of cargo landings for reliability evaluation before anyone flies on it.

But what if NASA never accepts propulsive landing on earth? Wouldn't this be a plus for SLS, DST, and Orion and a blow to the ITS architecture?

Unless NASA is paying for or flying on ITS, they don't really have any jurisdiction to say what SpaceX can or can't do. I think that would fall to the FAA.
Using NASA facilities gives them some say.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: envy887 on 07/20/2017 09:00 pm
I haven't seen any evidence that risk alone was NASA's hangup. Cost and schedule are significant issues for them as well.

The cost, risk and time combined to shelve the program.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Negan on 07/20/2017 09:05 pm
I haven't seen any evidence that risk alone was NASA's hangup. Cost and schedule are significant issues for them as well.

The cost, risk and time combined to shelve the program.

I would be in total agreement if they didn't refuse to let SpaceX attempt it on the cargo flights. Having another down mass option should have gave them to flexibility to accept the risk.

Edit: bolded what was ignored
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: envy887 on 07/20/2017 09:07 pm
Qualifying propulsive landing for cargo flights also adds extra cost and time, and risk to valuable NASA cargo...
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: jacqmans on 07/21/2017 09:09 am
Personnel from NASA, SpaceX and the U.S. Air Force have begun practicing recovery operations for the SpaceX Crew Dragon. Using a full-size model of the spacecraft that will take astronauts to the International Space Station, Air Force parajumpers practice helping astronauts out of the SpaceX Crew Dragon following a mission. In certain unusual recovery situations, SpaceX may need to work with Air Force for parajumpers to recover astronauts from the capsule following a water landing. The recovery trainer was recently lowered into the Indian River Lagoon near NASA’s Kennedy Space Center allowing Air Force pararescue and others to refine recovery procedures. SpaceX is developing the Crew Dragon in partnership with NASA’s Commercial Crew Program to carry astronauts to and from the International Space Station.

Photo credit: SpaceX
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Luc on 07/21/2017 01:41 pm
Exciting times.  After perusing the threads, I failed to find (doesn't mean it isn't there) anyone stating the obvious given the coincidence of resurrecting stage 2 reuse and postponing Dragon 2 propulsive landing.  Does it not make sense that given finite resources and an urgency to "move on" to development of some form of ITS, and in light of their mega constellation plans to re task resources from D2 propulsive landing to S2 recovery?  D2 propulsive landing will happen as soon as there is a compelling economic or strategic reason, just as S2 reuse is being resurrected now.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Lars-J on 07/21/2017 03:27 pm
Exciting times.  After perusing the threads, I failed to find (doesn't mean it isn't there) anyone stating the obvious given the coincidence of resurrecting stage 2 reuse and postponing Dragon 2 propulsive landing.  Does it not make sense that given finite resources and an urgency to "move on" to development of some form of ITS, and in light of their mega constellation plans to re task resources from D2 propulsive landing to S2 recovery?  D2 propulsive landing will happen as soon as there is a compelling economic or strategic reason, just as S2 reuse is being resurrected now.

Yes, it makes sense. Elon's talk of scaling down ITS makes it more likely to appear sooner. And it seems like they have also decided that the Dragon 2 propulsive landing - while cool and not completely ruled out in the future - is an evolutionary dead end. Their next launch system - the smaller ITS - will have a fully reusable upper which is likely very similar to the ITS spaceship. But there are other threads for discussing this.  :)
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Apollo_kid on 07/21/2017 08:05 pm
I was just thinking if the astronauts are a NASA asset, they could use NASA/military assets to recover the Dragon 2 capsule. This would be like a Apollo type recovery with large ships and helicopter support and navy para-jumpers. Could also be good PR for the NASA folks.
I thinking SpaceX should move on to lander based systems as Elon stated the earth has a large gravity well and atmosphere  that lends itself to capsule design what they have in the dragon system. So I think Elon probably is thinking of a type of lander for the moon.


Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Oli on 07/22/2017 12:18 pm
And it seems like they have also decided that the Dragon 2 propulsive landing - while cool and not completely ruled out in the future - is an evolutionary dead end.

Propulsive capsule-landing always seemed like an evolutionary dead end. Now they're stuck with a suboptimal design, looks like the first serious misstep to me.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: rockets4life97 on 07/22/2017 12:22 pm
Propulsive capsule-landing always seemed like an evolutionary dead end. Now they're stuck with a suboptimal design, looks like the first serious misstep to me.

I think the superdracos for launch abort could be considered an upgrade from a launch abort tower because (1) no separation event and (2) able to re-use them.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Jcc on 07/22/2017 12:47 pm
Propulsive capsule-landing always seemed like an evolutionary dead end. Now they're stuck with a suboptimal design, looks like the first serious misstep to me.

I think the superdracos for launch abort could be considered an upgrade from a launch abort tower because (1) no separation event and (2) able to re-use them.

Hopefully they can reuse them. As far as I know the plan is to use new D2 capsules each time for NASA flights until they can certify a refurbishment process. It took 10 D1 flights before they could refly one for cargo, and Elon just said that it cost about the same, even more, to refurbish as to build a new one. Hopefully that experience can transfer to D2/crew, and if they have a lot of non-NASA crew flights reuse Dragon2s for that.

In comparison, Boeing is planning on making exactly 2 Starliners for flight, but they have to replace at least the whole service module and heat shield for each reuse.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Ronsmytheiii on 07/22/2017 12:56 pm
I was just thinking if the astronauts are a NASA asset, they could use NASA/military assets to recover the Dragon 2 capsule. This would be like a Apollo type recovery with large ships and helicopter support and navy para-jumpers. Could also be good PR for the NASA folks.

Would imagine that they will just use their West coast ship like they do now for cargo Dragon flights.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: meekGee on 07/22/2017 05:12 pm
And it seems like they have also decided that the Dragon 2 propulsive landing - while cool and not completely ruled out in the future - is an evolutionary dead end.

Propulsive capsule-landing always seemed like an evolutionary dead end. Now they're stuck with a suboptimal design, looks like the first serious misstep to me.
Seemed to whom?

I don't see them being a "serious misstep", since Dragon is volume limited  and the NASA contracts remain the same.

Throwing away an abort tower each time would have been more expensive.

Plus, the R&D is not totally lost, and wherever propulsive landings you'll see in the future, it'll have D2 genes.

(And you will see propulsive landings in the future - what else is there that scales?)
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: intrepidpursuit on 07/23/2017 03:49 am
And it seems like they have also decided that the Dragon 2 propulsive landing - while cool and not completely ruled out in the future - is an evolutionary dead end.

Propulsive capsule-landing always seemed like an evolutionary dead end. Now they're stuck with a suboptimal design, looks like the first serious misstep to me.
Seemed to whom?

I don't see them being a "serious misstep", since Dragon is volume limited  and the NASA contracts remain the same.

Throwing away an abort tower each time would have been more expensive.

Plus, the R&D is not totally lost, and wherever propulsive landings you'll see in the future, it'll have D2 genes.

(And you will see propulsive landings in the future - what else is there that scales?)

A controlled landing using thrust differential on side mounted hypergolic engines and a ballast sled is absolutely a dead end. BFS lands just like F9, using thrust vectoring.

That being said, their abort system is still clearly the best design in use since it has no separation events and is reusable. I don't see it as a misstep. FH was way harder than they thought but they chose to continue with it; propulsively landing D2 proved to be harder than they thought and they shelved it for lack of utility.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: meekGee on 07/23/2017 03:56 am
And it seems like they have also decided that the Dragon 2 propulsive landing - while cool and not completely ruled out in the future - is an evolutionary dead end.

Propulsive capsule-landing always seemed like an evolutionary dead end. Now they're stuck with a suboptimal design, looks like the first serious misstep to me.
Seemed to whom?

I don't see them being a "serious misstep", since Dragon is volume limited  and the NASA contracts remain the same.

Throwing away an abort tower each time would have been more expensive.

Plus, the R&D is not totally lost, and wherever propulsive landings you'll see in the future, it'll have D2 genes.

(And you will see propulsive landings in the future - what else is there that scales?)

A controlled landing using thrust differential on side mounted hypergolic engines and a ballast sled is absolutely a dead end. BFS lands just like F9, using thrust vectoring.

That being said, their abort system is still clearly the best design in use since it has no separation events and is reusable. I don't see it as a misstep. FH was way harder than they thought but they chose to continue with it; propulsively landing D2 proved to be harder than they thought and they shelved it for lack of utility.
The ballast slide replaces fins, not engines.

Differential thrust, if appropriate, is a more responsive system then a gimbal.

However, since ITS is a second stage and an interplanetary vehicle, angled side thrusters don't make sense.

So all we have here is "customer didn't want it, and we have bigger fish to fry".

Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: intrepidpursuit on 07/23/2017 03:59 am
And it seems like they have also decided that the Dragon 2 propulsive landing - while cool and not completely ruled out in the future - is an evolutionary dead end.

Propulsive capsule-landing always seemed like an evolutionary dead end. Now they're stuck with a suboptimal design, looks like the first serious misstep to me.
Seemed to whom?

I don't see them being a "serious misstep", since Dragon is volume limited  and the NASA contracts remain the same.

Throwing away an abort tower each time would have been more expensive.

Plus, the R&D is not totally lost, and wherever propulsive landings you'll see in the future, it'll have D2 genes.

(And you will see propulsive landings in the future - what else is there that scales?)

A controlled landing using thrust differential on side mounted hypergolic engines and a ballast sled is absolutely a dead end. BFS lands just like F9, using thrust vectoring.

That being said, their abort system is still clearly the best design in use since it has no separation events and is reusable. I don't see it as a misstep. FH was way harder than they thought but they chose to continue with it; propulsively landing D2 proved to be harder than they thought and they shelved it for lack of utility.
The ballast slide replaces fins, not engines.

Differential thrust, if appropriate, is a more responsive system then a gimbal.

However, since ITS is a second stage and an interplanetary vehicle, angled side thrusters don't make sense.

So all we have here is "customer didn't want it, and we have bigger fish to fry".

Yes, exactly. If the customer doesn't want it and you don't need it, why in the world would you build it?

Sure, perhaps you could build BFS with a dragon style landing system, but they aren't. The technology is totally different and there will be very little data shared between D2 and BFS.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: su27k on 07/23/2017 04:11 am
And it seems like they have also decided that the Dragon 2 propulsive landing - while cool and not completely ruled out in the future - is an evolutionary dead end.

Propulsive capsule-landing always seemed like an evolutionary dead end.

It seems critical to the goal of rapid reuse, right now the flight rate doesn't require it, but it may be useful in the future if LEO crew traffic picks up significantly. A propulsive landed capsule + reuse of both F9 stages has the potential to bring down the ticket price to LEO significantly.

Quote
Now they're stuck with a suboptimal design, looks like the first serious misstep to me.

They have a good enough system for now, SpaceX is not after the optimal solution, they go for the most cost effective one.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: meekGee on 07/23/2017 04:52 am
And it seems like they have also decided that the Dragon 2 propulsive landing - while cool and not completely ruled out in the future - is an evolutionary dead end.

Propulsive capsule-landing always seemed like an evolutionary dead end. Now they're stuck with a suboptimal design, looks like the first serious misstep to me.
Seemed to whom?

I don't see them being a "serious misstep", since Dragon is volume limited  and the NASA contracts remain the same.

Throwing away an abort tower each time would have been more expensive.

Plus, the R&D is not totally lost, and wherever propulsive landings you'll see in the future, it'll have D2 genes.

(And you will see propulsive landings in the future - what else is there that scales?)

A controlled landing using thrust differential on side mounted hypergolic engines and a ballast sled is absolutely a dead end. BFS lands just like F9, using thrust vectoring.

That being said, their abort system is still clearly the best design in use since it has no separation events and is reusable. I don't see it as a misstep. FH was way harder than they thought but they chose to continue with it; propulsively landing D2 proved to be harder than they thought and they shelved it for lack of utility.
The ballast slide replaces fins, not engines.

Differential thrust, if appropriate, is a more responsive system then a gimbal.

However, since ITS is a second stage and an interplanetary vehicle, angled side thrusters don't make sense.

So all we have here is "customer didn't want it, and we have bigger fish to fry".

Yes, exactly. If the customer doesn't want it and you don't need it, why in the world would you build it?

Sure, perhaps you could build BFS with a dragon style landing system, but they aren't. The technology is totally different and there will be very little data shared between D2 and BFS.

It started with replying to the bolded comment above, which just mis-reads reality.

They are not stuck with anything, and nothing became an "evolutionary dead end".

As we agree, they built a capability, which still works for abort, and leaves some options available for Dragon if they decide to use it.

Beyond that, nothing happened.

Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Robotbeat on 07/23/2017 12:48 pm
And it seems like they have also decided that the Dragon 2 propulsive landing - while cool and not completely ruled out in the future - is an evolutionary dead end.

Propulsive capsule-landing always seemed like an evolutionary dead end. Now they're stuck with a suboptimal design, looks like the first serious misstep to me.
Seemed to whom?

I don't see them being a "serious misstep", since Dragon is volume limited  and the NASA contracts remain the same.

Throwing away an abort tower each time would have been more expensive.

Plus, the R&D is not totally lost, and wherever propulsive landings you'll see in the future, it'll have D2 genes.

(And you will see propulsive landings in the future - what else is there that scales?)

A controlled landing using thrust differential on side mounted hypergolic engines and a ballast sled is absolutely a dead end. BFS lands just like F9, using thrust vectoring.

That being said, their abort system is still clearly the best design in use since it has no separation events and is reusable. I don't see it as a misstep. FH was way harder than they thought but they chose to continue with it; propulsively landing D2 proved to be harder than they thought and they shelved it for lack of utility.
I think that Starliner's abort system is just as good in this regard.

The only notable difference is that Starliner expends them before reentry whereas SpaceX keeps them attached. That's both a good thing and a bad thing. It's good in that it is more mass efficient. Shedding them earlier means you don't need a heatshield and parachutes sized to carry the abort system back to Earth. On the other side, you don't get to reuse them.

IMHO it's a decent trade either way. Both Starliner and Dragon's abort systems are superior approaches to Orion's abort system, in my opinion. Of course Orion's LAS is designed for a much more challenging abort environment (Ares I).
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: woods170 on 07/23/2017 01:02 pm
Who says NASA has a problem with propulsive landing?

Humans, Jim. The question is propulsive landing and humans...
https://www.youtube.com/watch?v=k_OD2V6fMLQ
Different time Jim. NASA was willing to take much more risk back them. Challenger and Columbia killed that.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: AncientU on 07/23/2017 03:38 pm
And it seems like they have also decided that the Dragon 2 propulsive landing - while cool and not completely ruled out in the future - is an evolutionary dead end.

Propulsive capsule-landing always seemed like an evolutionary dead end. Now they're stuck with a suboptimal design, looks like the first serious misstep to me.

Capsules are a dead end.  Landing them in the ocean, while nicely retro, is also a dead end.  Launch abort towers are a dead end...  seems there is a bunch about this technology that isn't going anywhere.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: clongton on 07/23/2017 05:27 pm
[Steps up on soapbox]
Been stewing this over for the last few days. I am very sad to see Dragon's propulsive landing be cancelled, not because it was sexy or anything like that. It is because like Musk said back at  the D2 Reveal: "This is how spaceships are supposed to land". I believe that with all my heart - I *always* have believed that. Splashdowns were done because back in the day we didn't have a clue how to do anything else. To go back to them 50 years later as the primary recovery is so retro, so 1960's, so chickenshit. We have perfected propulsive landing on Mars for Pete's sake! The Soyuz actually uses it for the final seconds before they hit the ground. Legs coming out through the heatshield scares them? Where are the men who designed Big Gemini with a crew access hatch through the heatshield? NASA actually approved that design. We learned how to do and perfected propulsive landing on the Moon with crew onboard. Remember the LM? Yea, propulsive landing. Now this. What the hell is NASA thinking? It feels to me like they put on their brain-dead hats and told SpaceX to delete it. No guts. No forward thinking. Absolutely no desire to innovate! No wonder we spent 30 years going around in circles. There aren't any forward thinking people in leadership position at NASA anymore. As far as I am concerned there isn't any leadership at all at NASA anymore. Everybody is afraid of their own shadow. They remind me of the cowardly lion on the Yellow Brick Road. The NASA I grew up with is dead and gone. The NASA I was proud to serve doesn't exist anymore. Instead all we have is this shadow thing.
[Steps off soapbox]
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: philw1776 on 07/23/2017 05:33 pm
I see it as NASA having no substantive need for powered landing.  Ocean landings work well.  Why add complexity and potential risk?  NASA's mission is crew rotation. D2 with chutes meets the requirements.  NASA commercial crew contractors should focus on their goal, not SpaceX agendas for reuseability and other mission uses.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: clongton on 07/23/2017 05:39 pm
NASA has no substantive need for air bag landing either.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: vt_hokie on 07/23/2017 05:50 pm
I see it as NASA having no substantive need for powered landing.  Ocean landings work well.  Why add complexity and potential risk?

My question is this: if the hardware as it exists is capable of performing a powered landing (big if), why not add the software capability to use that as a backup in the event of a chute failure? 
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: philw1776 on 07/23/2017 05:52 pm
I see it as NASA having no substantive need for powered landing.  Ocean landings work well.  Why add complexity and potential risk?

My question is this: if the hardware as it exists is capable of performing a powered landing (big if), why not add the software capability to use that as a backup in the event of a chute failure?

1. Assumption stated
2. Time and $ to develop
3. Time & $ to test
4. Only known customer does not want it and it means a different V2 with landing legs thru heatshield, not allowed by only customer
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: vt_hokie on 07/23/2017 06:01 pm

4. Only known customer does not want it and it means a different V2 with landing legs thru heatshield, not allowed by only customer

I was thinking of the possibility of a soft propulsive water splashdown backup mode, but otherwise, point taken.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Jim on 07/23/2017 06:07 pm
Who said it was the legs?
This is just another one of the self perpetuating internet stories. 
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Jim on 07/23/2017 06:23 pm
People are taking NASA to task and don't know what they are talking about.

Nobody is stepping back and looking at what the issues are.

I don't have inside knowledge about this but it seems easy to figure out.

The issue is qualification of the landing system.  Let me ask how many flights is it taking the Falcon 9 to be qualified as a crew launch vehicle?

And how many flights of a propulsive landing Dragon would be required to qualify it (hover tests don't count)?
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Ictogan on 07/23/2017 06:25 pm
[Steps up on soapbox]
Been stewing this over for the last few days. I am very sad to see Dragon's propulsive landing be cancelled, not because it was sexy or anything like that. It is because like Musk said back at  the D2 Reveal: "This is how spaceships are supposed to land". I believe that with all my heart - I *always* have believed that. Splashdowns were done because back in the day we didn't have a clue how to do anything else. To go back to them 50 years later as the primary recovery is so retro, so 1960's, so chickenshit. We have perfected propulsive landing on Mars for Pete's sake! The Soyuz actually uses it for the final seconds before they hit the ground. Legs coming out through the heatshield scares them? Where are the men who designed Big Gemini with a crew access hatch through the heatshield? NASA actually approved that design. We learned how to do and perfected propulsive landing on the Moon with crew onboard. Remember the LM? Yea, propulsive landing. Now this. What the hell is NASA thinking? It feels to me like they put on their brain-dead hats and told SpaceX to delete it. No guts. No forward thinking. Absolutely no desire to innovate! No wonder we spent 30 years going around in circles. There aren't any forward thinking people in leadership position at NASA anymore. As far as I am concerned there isn't any leadership at all at NASA anymore. Everybody is afraid of their own shadow. They remind me of the cowardly lion on the Yellow Brick Road. The NASA I grew up with is dead and gone. The NASA I was proud to serve doesn't exist anymore. Instead all we have is this shadow thing.
[Steps off soapbox]
What makes you so sure that abandoning D2 propulsive landing was entirely due to NASA and that there weren't any concerns about it in SX as well?
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Flying Beaver on 07/23/2017 06:40 pm
Some simple envisioning of what we should be seeing within the next 4-6 months hanging from 39A's FSS  :D

edit: Fixed side, per old_sellsword.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: old_sellsword on 07/23/2017 06:42 pm
Some simple envisioning of what we should be seeing within the next 4-6 months hanging from 39A's FSS  :D

Great renders, but it’s on the wrong side.

https://flic.kr/p/GemUfy
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Flying Beaver on 07/23/2017 06:46 pm
Some simple envisioning of what we should be seeing within the next 4-6 months hanging from 39A's FSS  :D

Great renders, but it’s on the wrong side.

https://flic.kr/p/GemUfy

Hmm. So the same as Cargo Dragon (Z-). i.e lower side in reference to the seating and screens.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: clongton on 07/23/2017 06:55 pm
The issue is qualification of the landing system.  Let me ask how many flights is it taking the Falcon 9 to be qualified as a crew launch vehicle?

And how many flights of a propulsive landing Dragon would be required to qualify it (hover tests don't count)?

Per contract water landing was to be the default until propulsive landing was qualified and there was *no* time limit set for that qualification. Dragon-2 will be used for other than NASA flights. There is nothing in the specs that preclude SpaceX from qualifying propulsive landing with non-NASA flights. Nothing. I have been told that that is how it was planned to be done. NIH issue? Don't know but it was definitely on the NASA side, not SpaceX side, that the delete decision was made. SpaceX was told, not asked, to remove the capability. Elon was not happy but made the best of it that he could.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: philw1776 on 07/23/2017 06:59 pm
Who said it was the legs?
This is just another one of the self perpetuating internet stories.

"Musk admitted that Crew Dragon and, by extension, the often touted Red Dragon mission to Mars and various other Dragon missions to any other body within our Solar System, was altered when NASA insisted that the risk of landing legs piercing the heat shield be eliminated. Musk briefly explained that the capability was probably still there if they wanted to consider it in the future"

http://www.spaceflightinsider.com/organizations/space-exploration-technologies/musk-takes-crew-dragon-propulsive-landing-off-table-issrdc-talks-iss-moon-base/


Agreed that author Jerome Strach may well have gotten the paraphrase wrong.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: docmordrid on 07/23/2017 07:00 pm
The issue is qualification of the landing system.  Let me ask how many flights is it taking the Falcon 9 to be qualified as a crew launch vehicle?

And how many flights of a propulsive landing Dragon would be required to qualify it (hover tests don't count)?

Per contract water landing was to be the default until propulsive landing was qualified and there was *no* time limit set for that qualification. Dragon-2 will be used for other than NASA flights. There is nothing in the specs that preclude SpaceX from qualifying propulsive landing with non-NASA flights. Nothing. I have been told that that is how it was planned to be done. NIH issue? Don't know but it was definitely on the NASA side, not SpaceX side, that the delete decision was made. SpaceX was told, not asked, to remove the capability. Elon was not happy but made the best of it that he could.

And if there's a LOC due to the chutes failing and there is no 'Hail Mary' SD backup landing mode that decision will likely be a top item in the investigation.

Deja Vu, all over again.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Jim on 07/23/2017 07:14 pm
The issue is qualification of the landing system.  Let me ask how many flights is it taking the Falcon 9 to be qualified as a crew launch vehicle?

And how many flights of a propulsive landing Dragon would be required to qualify it (hover tests don't count)?

Per contract water landing was to be the default until propulsive landing was qualified and there was *no* time limit set for that qualification. Dragon-2 will be used for other than NASA flights. There is nothing in the specs that preclude SpaceX from qualifying propulsive landing with non-NASA flights. Nothing. I have been told that that is how it was planned to be done. NIH issue? Don't know but it was definitely on the NASA side, not SpaceX side, that the delete decision was made. SpaceX was told, not asked, to remove the capability. Elon was not happy but made the best of it that he could.

And if there's a LOC due to the chutes failing and there is no 'Hail Mary' SD backup landing mode that decision will likely be a top item in the investigation.

Deja Vu, all over again.

Not at all Deja Vu.  There are redundant  chutes.  Chutes are more reliable.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Ictogan on 07/23/2017 07:16 pm
The issue is qualification of the landing system.  Let me ask how many flights is it taking the Falcon 9 to be qualified as a crew launch vehicle?

And how many flights of a propulsive landing Dragon would be required to qualify it (hover tests don't count)?

Per contract water landing was to be the default until propulsive landing was qualified and there was *no* time limit set for that qualification. Dragon-2 will be used for other than NASA flights. There is nothing in the specs that preclude SpaceX from qualifying propulsive landing with non-NASA flights. Nothing. I have been told that that is how it was planned to be done. NIH issue? Don't know but it was definitely on the NASA side, not SpaceX side, that the delete decision was made. SpaceX was told, not asked, to remove the capability. Elon was not happy but made the best of it that he could.

And if there's a LOC due to the chutes failing and there is no 'Hail Mary' SD backup landing mode that decision will likely be a top item in the investigation.

Deja Vu, all over again.
So far not a single LOC has happened due to parachutes despite it being the most common way that spacecraft have landed. Such a chute failure seems unlikely to me. But if it would happen, the blame would likely rest more on whatever caused the parachute failure rather than the removal of propulsive landing. After all, properly designed parachutes have been proven to be extremely reliable.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Robotbeat on 07/23/2017 07:21 pm
The first Soyuz flight was a parachute failure that killed the sole cosmonaut on it. https://en.wikipedia.org/wiki/Soyuz_1
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Semmel on 07/23/2017 07:26 pm
I see it the same as clancton. I dont have his knowledge, but if it was a NASA decision, they violated the reason for their existence. The mission of NASA is to support and advance technology, something along these lines. Denying propulsive landing sounds like the opposite, hindering new technologies because they are not mission critical. At least not for this mission, despite being clearly superior. I am quite sad about this as well. But I dont want to put all the blame on NASA. SpaceX could continute with propulsive landing and develop Red Dragon regardless. They have their reason to not do it and if it helps to advance the 9m BFR, I kind of am in favor of doing that. But still, it sounds like a missed opportunity. Like a vanishing of synergies with good potentials.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: woods170 on 07/23/2017 07:27 pm
People are taking NASA to task and don't know what they are talking about.

Nobody is stepping back and looking at what the issues are.

I don't have inside knowledge about this but it seems easy to figure out.

The issue is qualification of the landing system.  Let me ask how many flights is it taking the Falcon 9 to be qualified as a crew launch vehicle?

And how many flights of a propulsive landing Dragon would be required to qualify it (hover tests don't count)?
Propulsive cargo landings were going to pave the way for propulsive crew landing. However,  NASA said "No" to those as well.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: philw1776 on 07/23/2017 07:29 pm
Who said it was the legs?
This is just another one of the self perpetuating internet stories.

"Musk admitted that Crew Dragon and, by extension, the often touted Red Dragon mission to Mars and various other Dragon missions to any other body within our Solar System, was altered when NASA insisted that the risk of landing legs piercing the heat shield be eliminated. Musk briefly explained that the capability was probably still there if they wanted to consider it in the future"

http://www.spaceflightinsider.com/organizations/space-exploration-technologies/musk-takes-crew-dragon-propulsive-landing-off-table-issrdc-talks-iss-moon-base/


Agreed that author Jerome Strach may well have gotten the paraphrase wrong.

Found root source.  It was interpreted from the post talk Q&A

https://www.facebook.com/photo.php?fbid=10213795081617618&set=p.10213795081617618&type=3&theater

Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Robotbeat on 07/23/2017 07:29 pm
A way could've been found to assuage NASA's concerns for cargo, and maybe eventually for crew, too.

But definitely not for free.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Jim on 07/23/2017 08:15 pm
People are taking NASA to task and don't know what they are talking about.

Nobody is stepping back and looking at what the issues are.

I don't have inside knowledge about this but it seems easy to figure out.

The issue is qualification of the landing system.  Let me ask how many flights is it taking the Falcon 9 to be qualified as a crew launch vehicle?

And how many flights of a propulsive landing Dragon would be required to qualify it (hover tests don't count)?
Propulsive cargo landings were going to pave the way for propulsive crew landing. However,  NASA said "No" to those as well.

Same issue, how many qual flights.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: meekGee on 07/23/2017 10:59 pm
From Musk's talk, we know he used to thing that heat-shield + legs is the best way to land on Mars, and that he no longer thinks that.

From his perspective, D2 no longer serves as a direct test bed for Mars technology.

So if NASA has cold feet, he's got zero motivation to push it.

He's got his contracts, he's the cheapest ride in town, and he's got much bigger fish to fry - that's all there is to it.

----

Parachutes are fine when coupled with water landing.
Parachutes are semi-fine for land landings (see the over-turned Soyuz capsules)

So if you're willing to settle for those half-assed landing scenarios, as NASA clearly is, then by all means, parachutes are the way to go.

If you want to move beyond that, to reusable vehicles that land with the intent of quickly taking off again - then parachutes are a non-starter.

It's an old-space new-space thing.  Good-enough vs. unacceptable.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Comga on 07/23/2017 11:12 pm
Does anything prevent SpaceX from testing propulsive landing during ocean landings?
Suppose the Dragon 2 starts up its SuperDracos at some small number of meters above the ocean.
They could be turned on briefly just to demonstrate that they can be reliably lit after reentry.
They could be used to do a Soyuz style softened landing on the ocean.
They could be used to slow to a stop and hover.
Not only would this demonstrate the SuperDracos but it would burn off some of the propellants.
What would be the issues?

(Someone is going to say "No need.  Not a requirement." but here is a posited purpose.  Saying it's not needed because land landings are not planned would be circular reasoning.)

Here's at least part of my answer:
Cargo Dragon 2 doesn't have launch abort system, so definitely no powered landing.
The hypothesized test would have to be done on Commercial Crew flights. 
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: AncientU on 07/23/2017 11:32 pm
People are taking NASA to task and don't know what they are talking about.

Nobody is stepping back and looking at what the issues are.

I don't have inside knowledge about this but it seems easy to figure out.

The issue is qualification of the landing system.  Let me ask how many flights is it taking the Falcon 9 to be qualified as a crew launch vehicle?

And how many flights of a propulsive landing Dragon would be required to qualify it (hover tests don't count)?
Propulsive cargo landings were going to pave the way for propulsive crew landing. However,  NASA said "No" to those as well.

Same issue, how many qual flights.

...
Splashdowns were done because back in the day we didn't have a clue how to do anything else. To go back to them 50 years later as the primary recovery is so retro, so 1960's, so chickenshit.
...
The NASA I was proud to serve doesn't exist anymore.
...

How many flights did Shuttle Orbiter fly before they qualified their landing gear penetrating the heat shield?
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Lars-J on 07/23/2017 11:46 pm
The first Soyuz flight was a parachute failure that killed the sole cosmonaut on it. https://en.wikipedia.org/wiki/Soyuz_1

No, there were unmanned test flights. (Which also had problems) The Soviets had a history of naming test flights as Cosmos.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Robotbeat on 07/23/2017 11:48 pm
The first Soyuz flight was a parachute failure that killed the sole cosmonaut on it. https://en.wikipedia.org/wiki/Soyuz_1

No, there were unmanned test flights. (Which also had problems) The Soviets had a history of naming test flights as Cosmos.
Huh? I was responding to someone who claimed there were no spaceflight fatalities from parachute failure. Your comment is irrelevant.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: philw1776 on 07/23/2017 11:50 pm
Who said it was the legs?
This is just another one of the self perpetuating internet stories.

"Musk admitted that Crew Dragon and, by extension, the often touted Red Dragon mission to Mars and various other Dragon missions to any other body within our Solar System, was altered when NASA insisted that the risk of landing legs piercing the heat shield be eliminated. Musk briefly explained that the capability was probably still there if they wanted to consider it in the future"

http://www.spaceflightinsider.com/organizations/space-exploration-technologies/musk-takes-crew-dragon-propulsive-landing-off-table-issrdc-talks-iss-moon-base/


Agreed that author Jerome Strach may well have gotten the paraphrase wrong.

Well, well, well, a retraction.

SpaceFlight Insider
2 hrs ·
On Jul 22, 2017 SpaceFlight Insider published an article that stated Elon Musk had said NASA insisted on having Crew Dragon land via parachute instead of propulsive means. Musk never said this and the article has been retracted. We at SpaceFlight Insider do our best to provide only accurate information and deeply apologize for this situation.


Kudos for issuing a retraction.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: alang on 07/24/2017 01:47 am
I'm not sure that I understand the strong reaction to the propulsive landing decision for Dragon 2.
SpaceX were going to do second stagevreuse, then they weren't and now they  might be again under some circumstances.
I can easily see SpaceX changing their minds again if non-NASA business became important enough .
Personally I thought that something as toxic as a hydrazine land landing wouldn't have appealed to the less aged spaceflight fans, but give it a few years and cleaner options might mature.
We could see still this resurrected, especially if the big rocket dreams remain as dreams.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Jim on 07/24/2017 01:54 am

How many flights did Shuttle Orbiter fly before they qualified their landing gear penetrating the heat shield?

the issue has nothing to do with heat shield penetration. 
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Lars-J on 07/24/2017 02:09 am
The first Soyuz flight was a parachute failure that killed the sole cosmonaut on it. https://en.wikipedia.org/wiki/Soyuz_1

No, there were unmanned test flights. (Which also had problems) The Soviets had a history of naming test flights as Cosmos.
Huh? I was responding to someone who claimed there were no spaceflight fatalities from parachute failure. Your comment is irrelevant.

Ah, never mind then, I thought the discussion was about vehicles with crewed first flights. Never mind!
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: clongton on 07/24/2017 11:54 am

How many flights did Shuttle Orbiter fly before they qualified their landing gear penetrating the heat shield?
the issue has nothing to do with heat shield penetration.

Huh? Opening a hole in the heat shield for the purpose of extending landing gear is the heat shield penetration issue.
Please explain your reasoning Jim. Thanks
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: LouScheffer on 07/24/2017 12:33 pm
I'm not sure that I understand the strong reaction to the propulsive landing decision for Dragon 2.

This, and the strong reaction to schedule slips for new development.  These kind of events are usual, if not inevitable, in new development and research.  Whenever you push a new idea, it almost always turns out to take longer, to be harder, more expensive, or riskier than you first thought, or it doesn't work as well as you imagined, or the customer does not want it.once all the tradeoffs are known concretely.

The ways around this are even worse, in my opinion.  You can work entirely in secret, only unveiling the final product (and not saying anything in the case of internal failure/cancellation).  In my limited experience this leads to engineering fiascoes of all kinds.  I suspect that if you could see inside black development programs, to the level of transparency currently exhibited by SpaceX, you'd find much more wasted effort, schedule slips, and other engineering and administrative mayhem.

Alternatively, you can pad the schedule and budget so much that you are sure you can deliver on time and on budget.   Then you'll likely turn off your customers with your expensive, late proposal, and lose business to your competitors who are not so conservative.  Plus you can even run over your conservative schedule, which looks really stupid.

So if you enjoy watching R&D as it happens, and seeing what organizations have in store, you are going to see projects cancelled and schedules slip.  That's part of the engineering trade for requesting transparency.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: robert_d on 07/24/2017 12:50 pm
How many flights did Shuttle Orbiter fly before they qualified their landing gear penetrating the heat shield?

It was even worse than that - two OPEN hatches (propellant feed lines) had to CLOSE completely or the crew was likely doomed.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Jim on 07/24/2017 01:12 pm

How many flights did Shuttle Orbiter fly before they qualified their landing gear penetrating the heat shield?
the issue has nothing to do with heat shield penetration.

Huh? Opening a hole in the heat shield for the purpose of extending landing gear is the heat shield penetration issue.
Please explain your reasoning Jim. Thanks

No where was it documented that NASA's "issue" with Dragon 2 focused solely on landing gear penetration.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: JamesH65 on 07/24/2017 02:02 pm

How many flights did Shuttle Orbiter fly before they qualified their landing gear penetrating the heat shield?
the issue has nothing to do with heat shield penetration.

Huh? Opening a hole in the heat shield for the purpose of extending landing gear is the heat shield penetration issue.
Please explain your reasoning Jim. Thanks

No where was it documented that NASA's "issue" with Dragon 2 focused solely on landing gear penetration.

That clearly doesn't answer the question asked. Would be interesting to actually have an answer to the question.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Jim on 07/24/2017 02:38 pm

How many flights did Shuttle Orbiter fly before they qualified their landing gear penetrating the heat shield?
the issue has nothing to do with heat shield penetration.

Huh? Opening a hole in the heat shield for the purpose of extending landing gear is the heat shield penetration issue.
Please explain your reasoning Jim. Thanks

No where was it documented that NASA's "issue" with Dragon 2 focused solely on landing gear penetration.

That clearly doesn't answer the question asked. Would be interesting to actually have an answer to the question.

 landing gear penetration has nothing to do with this topic and hence, the question is irrelevant.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: FutureSpaceTourist on 07/24/2017 03:17 pm
Not sure best thread for this, but sounds good for Dragon 2 flights next year:

Quote
Stephen Clark‏ @StephenClark1 8m8 minutes ago

NASA’s Greg Williams: Installation of SpaceX’s crew access arm and white room at pad 39A now planned for “late fall."

https://twitter.com/StephenClark1/status/889500990076055552
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Rocket Science on 07/24/2017 03:46 pm
My impression of this that goes back years when I stated this originally and never got an answer for is; that if you are descending for landing you will be at a decision height to commit to a fully propulsive landing which would be below the effective parachute deployment and inflation to safely land with no crew injuries. I interpreted this as analogous to "the "dead man zone" for the lunar landing sequence when during approach you could not safe descend below a safe decision height/velocity for abort back to orbit.
 
Bear in mind that my opinion was before the first ever landing of a first stage or the abort test. Now comparing the risk/reward to the first landing on the moon was of a different return compared to safe landing of crew or experiments from ISS. Now IMHO the return of S1 was extremely challenging and SpaceX brought me on side and increased my confidence in them. I would have liked to see SpaceX propulsively land as much as anyone else here however in the back of my mind is always is it worth the risk just to return from LEO compared to a lunar landing where a historically proven option was available for NASA flight crew using chutes. Dragon could still do airbag landings if incorporated in the future. Now if SpaceX wants to do propulsive landings for their own "private" crews they can still do so one their dime as long as they get clearance from regulatory agencies for tourists flights... If it proved to be reasonably "fail safe" is another matter...
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: vt_hokie on 07/24/2017 04:53 pm
Long term, I wonder if this has implications for the integrated launch abort Super Draco thrusters.  It's a shame to incur the mass penalty of carrying the hardware and propellant through the entire mission for no reason.  But on the other hand, the design of the vehicle is pretty much frozen at this point so that gets into longer term evolution issues.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Norm38 on 07/24/2017 05:05 pm
Does anything prevent SpaceX from testing propulsive landing during ocean landings?

They have to dump/use the fuel before reentry.  So it won't be possible to do testing.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: symbios on 07/24/2017 05:26 pm

How many flights did Shuttle Orbiter fly before they qualified their landing gear penetrating the heat shield?
the issue has nothing to do with heat shield penetration.

Huh? Opening a hole in the heat shield for the purpose of extending landing gear is the heat shield penetration issue.
Please explain your reasoning Jim. Thanks

No where was it documented that NASA's "issue" with Dragon 2 focused solely on landing gear penetration.

That clearly doesn't answer the question asked. Would be interesting to actually have an answer to the question.

 landing gear penetration has nothing to do with this topic and hence, the question is irrelevant.

So what you are saying is that it is qualifying the thrusters(software/hardware) for landing that is the problem and not the legs? Since this is the only two aspects that should need to be qualified for landing the dragon.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Ictogan on 07/24/2017 05:36 pm
Does anything prevent SpaceX from testing propulsive landing during ocean landings?

They have to dump/use the fuel before reentry.  So it won't be possible to do testing.
What makes you think that? The fact that they planned to use propulsively seems to imply to me that they have designed the heatshield to shield it even when fully fuelled and the parachutes are also likely designed for it being fully fuelled because they were the backup in case there was a problem with the SuperDracos on the way down.

Dumping fuel on the way down might give them better downmass capability, but that does by no means mean that they have to dump fuel before reentry.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: whitelancer64 on 07/24/2017 05:50 pm

No where was it documented that NASA's "issue" with Dragon 2 focused solely on landing gear penetration.

That clearly doesn't answer the question asked. Would be interesting to actually have an answer to the question.

 landing gear penetration has nothing to do with this topic and hence, the question is irrelevant.

So what you are saying is that it is qualifying the thrusters(software/hardware) for landing that is the problem and not the legs? Since this is the only two aspects that should need to be qualified for landing the dragon.

There's two issues here.

1. Elon Musk never said that the landing legs were the problem. As far as I can tell, Spaceflight Insider was the source of this claim, and they have now retracted that article. All Elon said is that they were deleted from the design after the decision to not go with propulsive landings was made.

2. There are a lot more issues with landing than just the thrusters and legs. Pre-landing-burn flight accuracy is one that I think may have been a significant issue. There are also abort contingencies, and the risk of system failures at low altitude. Qualifying the landing sequence for safety would have been both risky and time-consuming.

Ultimately, as Elon Musk said, SpaceX chose to change their plans and focus on refining the ITS project rather than waste time and energy on qualifying the Dragon for land landing.

Since the Dragon v2 CDR was completed last year, this decision must have been made some time ago.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Norm38 on 07/24/2017 06:08 pm
Dumping fuel on the way down might give them better downmass capability, but that does by no means mean that they have to dump fuel before reentry.

It's a NASA requirement, from earlier in this thread.  Now maybe it's not officially a requirement yet, and just speculation.  But no one has refuted it yet.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Jim on 07/24/2017 06:09 pm

So what you are saying is that it is qualifying the thrusters(software/hardware) for landing that is the problem and not the legs? Since this is the only two aspects that should need to be qualified for landing the dragon.

Qualifying the whole system and not just selecting parts
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Jim on 07/24/2017 06:11 pm
Qualifying the landing sequence for safety would have been both risky and time-consuming.


And would require dedicated launches. 
Cargo missions aren't available since it risks the cargo.
And it too heavy for helicopter drop (plus probably not high enough)
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: RDMM2081 on 07/24/2017 06:20 pm
Forgive the following if it is simply naive and ill-informed.

Part of the problem with the Dragon 2 system is that it needs to be tested and qualified before it can be used for NASA.  That is expensive and time consuming, neither of which SpaceX can afford right now.  But, what does this conversation look like one year from now, when SpaceX will likely have a hangar full of boosters, and the first couple landed Dragon 2 capsules, which (I could use some help confirming or citing this) NASA is effectively dis-allowing for re-use.  (I also seem to recall they dis-allowed re-use of Dragon 1 early in the COTS program, but here they are, using refurbished Dragon 1 capsules for CRS missions...)

Could or would SpaceX undertake a test program using majority recovered/refurbished equipment to finally establish the propulsive landing envelope for the Dragon 2 capsule?  I suppose my question isn't so much if they could, I think that ground "Dragonfly" tests, and suborbital tests (no 2nd stage) riding on a landed stage 1 booster, could be done super cheaply, basically just the cost of fuel and time, and a stage 1 -> Dragon 2 payload adapter in place of the interstage and stage 2.

Lots of fantastic arguments in the past few pages about how it is not the end of the world to be cancelling this capability in favor of re-assigning development teams to the ITS/ITSy, and I am not trying to argue against that.  BFR/BFS (whatever you want to call them, PLEASE SpaceX tell us a better name!) are the future, and the sooner you can get them flying the better.  But, if there is "free" hardware, how small of a team could you keep assigned to Dragon 2 propulsive landing, and maybe make it pay off while losing no appreciable time on ITSy development?  There are entire companies (RocketLabs) who are developing and flying hardware with < 200 employees, SpaceX is up near 5-6000 now, couldn't they keep a skeleton crew on the Dragon project and test if it has any of the merit they used to think it did?
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Jim on 07/24/2017 06:37 pm

1.   I suppose my question isn't so much if they could, I think that ground "Dragonfly" tests, and suborbital tests (no 2nd stage) riding on a landed stage 1 booster, could be done super cheaply, basically just the cost of fuel and time,

and a stage 1 -> Dragon 2 payload adapter in place of the interstage and stage 2.

 3.  But, if there is "free" hardware, how small of a team could you keep assigned to Dragon 2 propulsive landing, and maybe make it pay off while losing no appreciable time on ITSy development?  There are entire companies (RocketLabs) who are developing and flying hardware with < 200 employees, SpaceX is up near 5-6000 now, couldn't they keep a skeleton crew on the Dragon project and test if it has any of the merit they used to think it did?

1.  Who is going to update the avionics in the first stage for this?  Who is going to write the code for the new trajectory?  Where is it going to launch?  What launch pad?  Can the first stage even launch a Dragon into a representative trajectory?   Can the first stage get out of the way and not interfere with the Dragon landing while landing?
2. Who is going to design, build and qualify this adapter?

3. Can't be a separate "small" team.  The same people that design and operate the "existing" Dragon 2 will have to be involved with these launches.  Also, the launch team will have to be similar in make up to existing Dragon2/F9 team
(still have to assemble, test, load propellant, etc).
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: RDMM2081 on 07/24/2017 06:43 pm

1.   I suppose my question isn't so much if they could, I think that ground "Dragonfly" tests, and suborbital tests (no 2nd stage) riding on a landed stage 1 booster, could be done super cheaply, basically just the cost of fuel and time,

and a stage 1 -> Dragon 2 payload adapter in place of the interstage and stage 2.

 3.  But, if there is "free" hardware, how small of a team could you keep assigned to Dragon 2 propulsive landing, and maybe make it pay off while losing no appreciable time on ITSy development?  There are entire companies (RocketLabs) who are developing and flying hardware with < 200 employees, SpaceX is up near 5-6000 now, couldn't they keep a skeleton crew on the Dragon project and test if it has any of the merit they used to think it did?

1.  Who is going to update the avionics in the first stage for this?  Who is going to write the code for the new trajectory?  Where is it going to launch?  What launch pad?  Can the first stage even launch a Dragon into a representative trajectory?   Can the first stage get out of the way and not interfere with the Dragon landing while landing?
2. Who is going to design, build and qualify this adapter?

3. Can't be a separate "small" team.  The same people that design and operate the "existing" Dragon 2 will have to be involved with these launches.  Also, the launch team will have to be similar in make up to existing Dragon2/F9 team
(still have to assemble, test, load propellant, etc).

These are all questions I'm not qualified to answer, the only guess I had was non-numerical "skeleton crew" and comparing them to RocketLab's ~200 employees.  Do you have any estimates what size of work force would be needed to support a project this size, designing and modifying the items you identified?  (Let's ignore the pad part for now, just because)
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Jim on 07/24/2017 06:48 pm

These are all questions I'm not qualified to answer, the only guess I had was non-numerical "skeleton crew" and comparing them to RocketLab's ~200 employees.  Do you have any estimates what size of work force would be needed to support a project this size, designing and modifying the items you identified?  (Let's ignore the pad part for now, just because)

My point is that it would be the same team that is doing Dragon 2 now.

Rocketlab is not doing a project of the same complexity.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: RDMM2081 on 07/24/2017 06:51 pm

These are all questions I'm not qualified to answer, the only guess I had was non-numerical "skeleton crew" and comparing them to RocketLab's ~200 employees.  Do you have any estimates what size of work force would be needed to support a project this size, designing and modifying the items you identified?  (Let's ignore the pad part for now, just because)

My point is that it would be the same team that is doing Dragon 2 now.

Rocketlab is not doing a project of the same complexity.

Fair enough, point taken.

Seems SpaceX is pretty far past the "launch it and see what happens" (dramatic oversimplification, sorry!) and firmly in the established aerospace industry "establishment" now.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: FutureSpaceTourist on 07/24/2017 07:41 pm
Quote
A look at some SpaceX milestones for commercial crew. They've got a lot of work to do.

https://twitter.com/sciguyspace/status/889562804348497920
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: FutureSpaceTourist on 07/24/2017 07:43 pm
Quote
SpaceX has four Dragon crew modules in production.

https://twitter.com/sciguyspace/status/889563966317486081 (https://twitter.com/sciguyspace/status/889563966317486081)
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: LooksFlyable on 07/24/2017 07:52 pm
Have there been any images or videos of the ongoing parachute drop tests? I can't remember seeing any recently.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Space OurSoul on 07/24/2017 08:27 pm
Long term, I wonder if this has implications for the integrated launch abort Super Draco thrusters.  It's a shame to incur the mass penalty of carrying the hardware and propellant through the entire mission for no reason.  But on the other hand, the design of the vehicle is pretty much frozen at this point so that gets into longer term evolution issues.

It's amusing to contemplate Crew Dragon reverting to a tower LAS, but of course SpaceX-style where the tower does a bost-back burn and lands tail-first on legs that double as the latticework frame that attached it to the Dragon. And then we'll have a thread speculating what mods they'll make to it to allow recovery after one orbit, in order to cover the whole ascent profile.

But now that I think of this, it kinda answers your question: you carry the LAS to orbit so you can escape from the second stage too. I sardonically note that it would likely then be more-accurately termed a system for escaping from COPVs.


Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Kansan52 on 07/24/2017 08:36 pm
OK, I've missed it until the above chart. What is Dragon claw?
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: russianhalo117 on 07/24/2017 08:38 pm
Long term, I wonder if this has implications for the integrated launch abort Super Draco thrusters.  It's a shame to incur the mass penalty of carrying the hardware and propellant through the entire mission for no reason.  But on the other hand, the design of the vehicle is pretty much frozen at this point so that gets into longer term evolution issues.

It's amusing to contemplate Crew Dragon reverting to a tower LAS, but of course SpaceX-style where the tower does a bost-back burn and lands tail-first on legs that double as the latticework frame that attached it to the Dragon. And then we'll have a thread speculating what mods they'll make to it to allow recovery after one orbit, in order to cover the whole ascent profile.

But now that I think of this, it kinda answers your question: you carry the LAS to orbit so you can escape from the second stage too. I sardonically note that it would likely then be more-accurately termed a system for escaping from COPVs.



Abort Propellant is still used during nominal mission on orbit and during return to earth just not during landing phase anymore.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: whitelancer64 on 07/24/2017 08:46 pm
OK, I've missed it until the above chart. What is Dragon claw?
It's the umbilical between the Dragon and the rest of the rocket.

https://twitter.com/quantumg/status/205833676800540673
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: philw1776 on 07/24/2017 09:31 pm
Long term, I wonder if this has implications for the integrated launch abort Super Draco thrusters.  It's a shame to incur the mass penalty of carrying the hardware and propellant through the entire mission for no reason.  But on the other hand, the design of the vehicle is pretty much frozen at this point so that gets into longer term evolution issues.

Why is it a shame or a problem?  The F9 can easily launch a loaded Dragon 2 AND do RTLS.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: intrepidpursuit on 07/24/2017 10:57 pm
Long term, I wonder if this has implications for the integrated launch abort Super Draco thrusters.  It's a shame to incur the mass penalty of carrying the hardware and propellant through the entire mission for no reason.  But on the other hand, the design of the vehicle is pretty much frozen at this point so that gets into longer term evolution issues.

To me this is very "old space" thinking. Right there with the argument that reusing Falcon is stupid because it reduces its total payload to orbit, no matter what the resulting payload to orbit actually is.

If it can be carried with and reused and still accomplish the mission safely, then it is the right move.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Kansan52 on 07/24/2017 11:14 pm
It's the umbilical between the Dragon and the rest of the rocket.

Thanks!
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: brickmack on 07/24/2017 11:19 pm
Long term, I wonder if this has implications for the integrated launch abort Super Draco thrusters.  It's a shame to incur the mass penalty of carrying the hardware and propellant through the entire mission for no reason.  But on the other hand, the design of the vehicle is pretty much frozen at this point so that gets into longer term evolution issues.

Each SD is only a couple kilos, maybe a couple dozen accounting for the whole nacelle. All the abort fuel is shared with maneuvering, so no extra there either. And Dragons cargo load is volume limited, not mass limited. On the LV side, a tower LAS would add likely a ton or more, though it would be ditched early on
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: russianhalo117 on 07/24/2017 11:48 pm
Long term, I wonder if this has implications for the integrated launch abort Super Draco thrusters.  It's a shame to incur the mass penalty of carrying the hardware and propellant through the entire mission for no reason.  But on the other hand, the design of the vehicle is pretty much frozen at this point so that gets into longer term evolution issues.

Each SD is only a couple kilos, maybe a couple dozen accounting for the whole nacelle. All the abort fuel is shared with maneuvering, so no extra there either. And Dragons cargo load is volume limited, not mass limited. On the LV side, a tower LAS would add likely a ton or more, though it would be ditched early on
It makes it more Mass efficient for both the rocket and spacecraft to orbit since a solid/liquid fueled tower LAS would be omitted.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Lars-J on 07/25/2017 12:06 am
Long term, I wonder if this has implications for the integrated launch abort Super Draco thrusters.  It's a shame to incur the mass penalty of carrying the hardware and propellant through the entire mission for no reason.  But on the other hand, the design of the vehicle is pretty much frozen at this point so that gets into longer term evolution issues.

Each SD is only a couple kilos, maybe a couple dozen accounting for the whole nacelle. All the abort fuel is shared with maneuvering, so no extra there either. And Dragons cargo load is volume limited, not mass limited. On the LV side, a tower LAS would add likely a ton or more, though it would be ditched early on
It makes it more Mass efficient for both the rocket and spacecraft to orbit since a solid/liquid fueled tower LAS would be omitted.

That's old-school thinking, and as it happens BOTH of the commercial crew providers carry their LAS engines to orbit. Both use the propellant for either abort or orbital maneuvers including de-orbit. (even ISS reboost)

The propellant is the majority of the LAS system weight. Not the engines themselves.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Nomadd on 07/25/2017 12:09 am
 Will they carry extra propellant for abort, or is the amount used for normal ops enough?
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: russianhalo117 on 07/25/2017 12:45 am
Will they carry extra propellant for abort, or is the amount used for normal ops enough?
all prop used on orbit is burned util depletion during abort. The amount carried may have increased slightly when comparing Dragon v1 to Dragon v2.

Long term, I wonder if this has implications for the integrated launch abort Super Draco thrusters.  It's a shame to incur the mass penalty of carrying the hardware and propellant through the entire mission for no reason.  But on the other hand, the design of the vehicle is pretty much frozen at this point so that gets into longer term evolution issues.

Each SD is only a couple kilos, maybe a couple dozen accounting for the whole nacelle. All the abort fuel is shared with maneuvering, so no extra there either. And Dragons cargo load is volume limited, not mass limited. On the LV side, a tower LAS would add likely a ton or more, though it would be ditched early on
It makes it more Mass efficient for both the rocket and spacecraft to orbit since a solid/liquid fueled tower LAS would be omitted.

That's old-school thinking, and as it happens BOTH of the commercial crew providers carry their LAS engines to orbit. Both use the propellant for either abort or orbital maneuvers including de-orbit. (even ISS reboost)

The propellant is the majority of the LAS system weight. Not the engines themselves.
If a v2 Dragon with a traditional jettisonable LAS was launched on a Falcon 9 it would being carrying a significant amount of additional wet mass up until LAS separation compared to a built in LAS which has a lower constant wet mass value until fired, thus Dragon and Starliner away more mass efficient than say Orion.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Nomadd on 07/25/2017 01:54 am
Will they carry extra propellant for abort, or is the amount used for normal ops enough?
all prop used on orbit is burned util depletion during abort. The amount carried may have increased slightly when comparing Dragon v1 to Dragon v2.

My point being, propulsive landing would require more propellant if orbital ops amount was enough for the LAS so deletion should help payload.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: woods170 on 07/25/2017 09:10 pm
People are taking NASA to task and don't know what they are talking about.

Nobody is stepping back and looking at what the issues are.

I don't have inside knowledge about this but it seems easy to figure out.

The issue is qualification of the landing system.  Let me ask how many flights is it taking the Falcon 9 to be qualified as a crew launch vehicle?

And how many flights of a propulsive landing Dragon would be required to qualify it (hover tests don't count)?
Propulsive cargo landings were going to pave the way for propulsive crew landing. However,  NASA said "No" to those as well.

Same issue, how many qual flights.
None for STS but multiple for others. NASA is using double standards.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Jim on 07/25/2017 09:38 pm
None for STS but multiple for others. NASA is using double standards.

No, that was more than 35 years ago and NASA learned the error of its ways.  Orion was not manned for its first flight.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Kansan52 on 07/25/2017 11:06 pm
I had the impression that D1 would do cargo and D2 was only crew. So no propulsive landing due to that factor. Earlier it seemed that D2 may do both but that seemed to change with refurb D1s.

No evidence just the impression from reading posts here.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Basto on 07/25/2017 11:09 pm
None for STS but multiple for others. NASA is using double standards.

No, that was more than 35 years ago and NASA learned the error of its ways.  Orion was not manned for its first flight.

Really?  The main reason that NASA is not pushing away at a manned EM-1 right is money. If congress and the administration opened up the check book they would be on that path now.

I agree with woods on this one. Major double standard.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Jim on 07/25/2017 11:20 pm
None for STS but multiple for others. NASA is using double standards.

No, that was more than 35 years ago and NASA learned the error of its ways.  Orion was not manned for its first flight.

Really?  The main reason that NASA is not pushing away at a manned EM-1 right is money. If congress and the administration opened up the check book they would be on that path now.

I agree with woods on this one. Major double standard.

Wrong.  Even with money they would not have done it
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Owlon on 07/26/2017 01:51 am
None for STS but multiple for others. NASA is using double standards.

No, that was more than 35 years ago and NASA learned the error of its ways.  Orion was not manned for its first flight.

Really?  The main reason that NASA is not pushing away at a manned EM-1 right is money. If congress and the administration opened up the check book they would be on that path now.

I agree with woods on this one. Major double standard.

Wrong.  Even with money they would not have done it

I get the impression that the manned EM-1 study was due to pressure from outside NASA, and that NASA was pretty broadly opposed to the idea (hence the ultimate rejection). Is that more or less right, Jim?
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: soltasto on 07/26/2017 01:56 pm
None for STS but multiple for others. NASA is using double standards.

No, that was more than 35 years ago and NASA learned the error of its ways.  Orion was not manned for its first flight.

My understanding is that since it's a test mission, they just want to test the rocket and see how it performs. Sure, money would have been needed for the ECLSS and other stuff to get humans on it, but the unexpected can't be bought.

Really?  The main reason that NASA is not pushing away at a manned EM-1 right is money. If congress and the administration opened up the check book they would be on that path now.

I agree with woods on this one. Major double standard.

Wrong.  Even with money they would not have done it

I get the impression that the manned EM-1 study was due to pressure from outside NASA, and that NASA was pretty broadly opposed to the idea (hence the ultimate rejection). Is that more or less right, Jim?
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: notsorandom on 07/26/2017 02:59 pm
The Shuttle had 5 ALT flights before STS-1. There were many never tried before things done on STS-1 but the landing part was tested beforehand pretty well. There doesn't seem to be a way to test the Dragon's propulsive landing short of an orbital or sub orbital flight on a Falcon. Looks like NASA doesn't want to risk its cargo or crew and SpaceX doesn't want to pay for a number of dedicated test flights to prove it out.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: abaddon on 07/26/2017 03:30 pm
There doesn't seem to be a way to test the Dragon's propulsive landing short of an orbital or sub orbital flight on a Falcon.
What?  A drop test would be a fine way to test the landing, easily equivalent to Shuttle ALT flights.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Thorny on 07/26/2017 03:37 pm
And it too heavy for helicopter drop (plus probably not high enough)

What about out the back of a C-17, like Orion chute tests?
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Prettz on 07/26/2017 04:09 pm
The Shuttle had 5 ALT flights before STS-1. There were many never tried before things done on STS-1 but the landing part was tested beforehand pretty well. There doesn't seem to be a way to test the Dragon's propulsive landing short of an orbital or sub orbital flight on a Falcon. Looks like NASA doesn't want to risk its cargo or crew and SpaceX doesn't want to pay for a number of dedicated test flights to prove it out.
Then why wasn't the cost part of their bid? Or was it.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: StuffOfInterest on 07/26/2017 05:31 pm
Has there been any word of what happened with the tethered Dragonfly testing?  Considering that SpaceX was working on the dynamics of landing under power I wonder if they learned something about control stability that led them to decide it wasn't worth pushing forward.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: LooksFlyable on 07/26/2017 05:40 pm
Suggest the lack of anything beyond water landing is due to mutual lack of interest by NASA and SX, for different reasons.

SX reasons don't need to be remarked upon. NASA's do, but are unacceptable to have a professional discourse on.

I wanted propulsive Dragon, but I never liked the idea of last second hoverslam propulsive landings. It just seems like too much risk when you can have a system of retroburning high above the atmosphere then triple redundant parachutes for landing, and maybe just using propulsion to guide it, or using that as a last resort if parachutes fail. Perhaps using an inflatable heat shield as well. I just know I would want more safety systems on a human rated vehicle. Having said that, for some cargo missions, you can take a chance, so I'm still disappointed that they completely axed it since that will push back the day when we will truly have a fully reusable, easy to refurbish system. They might not even be the first ones to achieve that goal now, depending on how long the new ITS will take to complete.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Space Ghost 1962 on 07/26/2017 06:53 pm
Suggest the lack of anything beyond water landing is due to mutual lack of interest by NASA and SX, for different reasons.

SX reasons don't need to be remarked upon. NASA's do, but are unacceptable to have a professional discourse on.

I wanted propulsive Dragon, but I never liked the idea of last second hoverslam propulsive landings. It just seems like too much risk when you can have a system of retroburning high above the atmosphere then triple redundant parachutes for landing, and maybe just using propulsion to guide it, or using that as a last resort if parachutes fail. Perhaps using an inflatable heat shield as well. I just know I would want more safety systems on a human rated vehicle. Having said that, for some cargo missions, you can take a chance, so I'm still disappointed that they completely axed it since that will push back the day when we will truly have a fully reusable, easy to refurbish system. They might not even be the first ones to achieve that goal now, depending on how long the new ITS will take to complete.

Soyuz has always done partially propulsive "land" landings. No reason Dragon 2 couldn't as well.

Should be professionally discussed w/o childish issues. Really, really annoying.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Jim on 07/26/2017 06:58 pm
There doesn't seem to be a way to test the Dragon's propulsive landing short of an orbital or sub orbital flight on a Falcon.
What?  A drop test would be a fine way to test the landing, easily equivalent to Shuttle ALT flights.

how are you going to drop a spacecraft with hypergols? It is too heavy for helicopter
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Jim on 07/26/2017 08:33 pm
There doesn't seem to be a way to test the Dragon's propulsive landing short of an orbital or sub orbital flight on a Falcon.
What?  A drop test would be a fine way to test the landing, easily equivalent to Shuttle ALT flights.

how are you going to drop a spacecraft with hypergols? It is too heavy for helicopter
http://www.helipress.net/schede-708-the_top_5_heavy_lift_helicopters_video

Too heavy for number 4 & 5.  Musk is not going to use Russian copters, plus I doubt they are certified in the US.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: LooksFlyable on 07/26/2017 08:43 pm
Suggest the lack of anything beyond water landing is due to mutual lack of interest by NASA and SX, for different reasons.

SX reasons don't need to be remarked upon. NASA's do, but are unacceptable to have a professional discourse on.

I wanted propulsive Dragon, but I never liked the idea of last second hoverslam propulsive landings. It just seems like too much risk when you can have a system of retroburning high above the atmosphere then triple redundant parachutes for landing, and maybe just using propulsion to guide it, or using that as a last resort if parachutes fail. Perhaps using an inflatable heat shield as well. I just know I would want more safety systems on a human rated vehicle. Having said that, for some cargo missions, you can take a chance, so I'm still disappointed that they completely axed it since that will push back the day when we will truly have a fully reusable, easy to refurbish system. They might not even be the first ones to achieve that goal now, depending on how long the new ITS will take to complete.

Soyuz has always done partially propulsive "land" landings. No reason Dragon 2 couldn't as well.

Should be professionally discussed w/o childish issues. Really, really annoying.

I don't think you understood what I said. Soyuz using retro-burns to cushion the landing is actually an example of what I am saying.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: yg1968 on 07/26/2017 09:05 pm
People are taking NASA to task and don't know what they are talking about.

Nobody is stepping back and looking at what the issues are.

I don't have inside knowledge about this but it seems easy to figure out.

The issue is qualification of the landing system.  Let me ask how many flights is it taking the Falcon 9 to be qualified as a crew launch vehicle?

And how many flights of a propulsive landing Dragon would be required to qualify it (hover tests don't count)?
Propulsive cargo landings were going to pave the way for propulsive crew landing. However,  NASA said "No" to those as well.

Same issue, how many qual flights.
None for STS but multiple for others. NASA is using double standards.

A demo uncrewed flight wasn't actually required by NASA for CtCap but both providers proposed it.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: envy887 on 07/26/2017 09:05 pm
There doesn't seem to be a way to test the Dragon's propulsive landing short of an orbital or sub orbital flight on a Falcon.
What?  A drop test would be a fine way to test the landing, easily equivalent to Shuttle ALT flights.

how are you going to drop a spacecraft with hypergols? It is too heavy for helicopter
http://www.helipress.net/schede-708-the_top_5_heavy_lift_helicopters_video

Too heavy for number 4 & 5.  Musk is not going to use Russian copters, plus I doubt they are certified in the US.

The CH-53E can carry slung loads of up to about 36,000 lb, while the Dragonfly test article was about 14,000 lb.

What's your basis for stating that Dragon would be too heavy for it to lift?
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Jim on 07/26/2017 09:44 pm

The CH-53E can carry slung loads of up to about 36,000 lb, while the Dragonfly test article was about 14,000 lb.

What's your basis for stating that Dragon would be too heavy for it to lift?

The service ceiling is only around 18,000 ft and it would be much lower with such a load.  And 18k ft itself, is likely too low for such a test.

This is for qualification.  It would be flight weight spacecraft, much heavier than Dragonfly
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: envy887 on 07/26/2017 11:41 pm
DragonFly was actually ~18,000 lb (8150 kg) when including the fuel load, which is probably more reflective of flight weight after entry. It would be heavier pre-entry with the trunk and unpressurized cargo. It could well be that no helicopter with that load can reach the combination of altitude and speed needed to simulate landing.

A cargo plane or balloon might, though. Starliner recently used a balloon to reach 40,000 ft, and SpaceX has used plane drops for Dragon parachute tests.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: JBF on 07/27/2017 12:13 am
If I had to guess, it all came down to NASA was not willing to let them experiment with the cargo dragon in order to prove out the design and SpaceX was unwilling to fund it alone once they decided that it was not the best way to do things.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Comga on 07/27/2017 02:36 am
how are you going to drop a spacecraft with hypergols? (Snip)

Please explain your comment about hypergols
Hypergols mean it can't be carried within a C5?
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: drnscr on 07/27/2017 03:19 am
Well, if I were on that C5, I damned sure wouldn't want a crap load of hypergols on the same plane as me...
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Nomadd on 07/27/2017 04:16 am
 It's not so much being on the plane as what happens if it flunks the test.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Ike17055 on 07/27/2017 04:16 am
[Steps up on soapbox]
Been stewing this over for the last few days. I am very sad to see Dragon's propulsive landing be cancelled, not because it was sexy or anything like that. It is because like Musk said back at  the D2 Reveal: "This is how spaceships are supposed to land". I believe that with all my heart - I *always* have believed that. Splashdowns were done because back in the day we didn't have a clue how to do anything else. To go back to them 50 years later as the primary recovery is so retro, so 1960's, so chickenshit. We have perfected propulsive landing on Mars for Pete's sake! The Soyuz actually uses it for the final seconds before they hit the ground. Legs coming out through the heatshield scares them? Where are the men who designed Big Gemini with a crew access hatch through the heatshield? NASA actually approved that design. We learned how to do and perfected propulsive landing on the Moon with crew onboard. Remember the LM? Yea, propulsive landing. Now this. What the hell is NASA thinking? It feels to me like they put on their brain-dead hats and told SpaceX to delete it. No guts. No forward thinking. Absolutely no desire to innovate! No wonder we spent 30 years going around in circles. There aren't any forward thinking people in leadership position at NASA anymore. As far as I am concerned there isn't any leadership at all at NASA anymore. Everybody is afraid of their own shadow. They remind me of the cowardly lion on the Yellow Brick Road. The NASA I grew up with is dead and gone. The NASA I was proud to serve doesn't exist anymore. Instead all we have is this shadow thing.
[Steps off soapbox]

Too many red herrings to even address...

Yes, splashdowns were done "back in the sixties"...when our space program was at its peak. Cars had wheels then too. Are wheels now outdated?

Propulsive landing on the moon...yes, in a very limited gravity well, not like Earth.

Propulsive landing on Mars...yes, but not with crew at risk.

Heat shield crew hatch? Yes, but it never was allowed to fly, and was never revisited for future projects.

NASA isn't brain dead, and they are not forgetting that Challenger and Columbia could have sunk the manned space program if people believed that NASA was reckless.

Reliability is not a dirty word. And proven technologies are not bad either. Soyuz is the most successful spacecraft ever...yet it is using "old technology."  America has been grounded several times over the years, several times for multiple years, in its quest for the newest...yet Some variant of Soyuz has flown through all of them, even carrying America back into space on the heels of its (temporary) failures. NASA is proving it is not afraid to learn from history, from its past mistakes, and yes, even from the Russians. That is not brain-dead, that is smart. Very smart.
 

Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: rpapo on 07/27/2017 10:00 am
Well, if I were on that C5, I damned sure wouldn't want a crap load of hypergols on the same plane as me...
I'm not sure how that's worse than carrying a bunch of military equipment, especially ammunition and such.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: DeanG1967 on 07/27/2017 11:24 am
Ammunition doesn't light off if the powder accidently hits the primer (since it is always in contact with it

BIG Difference

Since if you had a Hypergol leak in air...the resulting "firing" would melt aircraft grade aluminum instantly (trust me...after 27 years of flying fighters in the USAF...being in the air, and on fire...is NOT FUN since you can't just pull over)
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: kevinof on 07/27/2017 11:34 am
I think, at this stage , with many successful launches and landings of Dragon 1, SpaceX have a good handle on taking care of Hypergols.  The chances of a leak while on the aircraft, are about as regular as leaks while on the stack, in orbit or landing. Far as I know there have been none.

I think we're overflowing this a bit.

Ammunition doesn't light off if the powder accidently hits the primer (since it is always in contact with it

BIG Difference

Since if you had a Hypergol leak in air...the resulting "firing" would melt aircraft grade aluminum instantly (trust me...after 27 years of flying fighters in the USAF...being in the air, and on fire...is NOT FUN since you can't just pull over)
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Jim on 07/27/2017 01:13 pm
I think, at this stage , with many successful launches and landings of Dragon 1, SpaceX have a good handle on taking care of Hypergols.  The chances of a leak while on the aircraft, are about as regular as leaks while on the stack, in orbit or landing. Far as I know there have been none.

I think we're overflowing this a bit.


Not really.  Why are there propellant vapor detectors in every facility that houses hypergols?  Why is there emergency breathing apparatus all such facilities?

And you would not know if there was a leak/spill during ground processing in the past.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: abaddon on 07/27/2017 03:53 pm
My conclusion after reading everything is that SpaceX could feasibly drop test a Souyz-style landing, which would allow them to land on land similar to the CST-100, if they wanted to.  Doesn't require much fuel at all, and they are already running drop tests to test the parachutes.

Either way, it's gone, so not much use debating about it.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Basto on 07/27/2017 04:32 pm
How fast would the capsule be traveling at the point of the landing burn?  Unless it would have decelerated to terminal velocity a plane or helo drop test would not be sufficient to prove the technology. Also I assume they would need to make some some adjustment burns during the descent to maintain a precision landing.

I don't see anyway around full orbital tests. NASA didn't want the cargo missions to double as tests (rightfully so). SpaceX didn't want to invest the resources to do this on their own.

It's a bummer because propulsive landing is freaking cool. But I get it.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: abaddon on 07/27/2017 04:49 pm
How fast would the capsule be traveling at the point of the landing burn?
If you're replying to my post, it would be traveling at whatever the terminal velocity of the capsule under chutes is.  Which is exactly what you would want for a last-second Soyuz-style retropropulsion to cushion the landing.

If you're talking about a full-up test, I do believe the propulsive burn was supposed to begin after the capsule had reached terminal velocity.  And I do not believe there were ever any plans to make "adjustment burns during descent" prior to the landing burn.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Basto on 07/27/2017 06:26 pm
How fast would the capsule be traveling at the point of the landing burn?
If you're replying to my post, it would be traveling at whatever the terminal velocity of the capsule under chutes is.  Which is exactly what you would want for a last-second Soyuz-style retropropulsion to cushion the landing.

If you're talking about a full-up test, I do believe the propulsive burn was supposed to begin after the capsule had reached terminal velocity.  And I do not believe there were ever any plans to make "adjustment burns during descent" prior to the landing burn.

I was not specifically replying to you otherwise I would have quoted.

I find it hard to believe that the capsule will have decelerated to terminal velocity without the use of chutes, but this is not based on any specific knowledge.

I believe that propulsive landing was intended as a replacement for chutes as once you add chutes to the equation pinpoint landings go out the window.  If you look at the SpaceX concept animations there were not any chutes deployed. So testing with chutes does not prove much.

Was the capsule intended to manage its trajectory in the atmosphere solely by shifting it's CG (using the sled)? That is also something that cannot be tested very effectively from a drop as you would need to test at much higher velocities.

The point I was making is that drop tests while they may give you some useful data points cannot replace a full up orbital test. And there would probably be a few early tests with a high chance of catastrophic failure (see early F9 landings).
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: BobHk on 07/27/2017 06:51 pm
If the Dragon cap needs to be transported and hypergols are an issue (they are if they leak) transport it inside a container with a detector/AES (auto extinguisher unit with something like zeenkleen ready to go off if the hydrazine does leak) built into the transport container. 
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: whitelancer64 on 07/27/2017 07:08 pm
Accelerated. Accelerated to terminal velocity, not decelerated.

I'm not sure what it would be for a capsule, but skydivers reach terminal velocity in about 500 meters.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Basto on 07/27/2017 07:23 pm
Accelerated. Accelerated to terminal velocity, not decelerated.

I'm not sure what it would be for a capsule, but skydivers reach terminal velocity in about 500 meters.

A capsule reentering from orbit would be decelerating. I stand by my word choice.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: SDSmith on 07/27/2017 10:53 pm
If the Dragon cap needs to be transported and hypergols are an issue (they are if they leak) transport it inside a container with a detector/AES (auto extinguisher unit with something like zeenkleen ready to go off if the hydrazine does leak) built into the transport container.

Use Stratolaunch to carry Dragon. Dragon is hanging off the external mount between the wings and the hypergols should only be a problem at launch for the ground crews.

NASA posted a film on YouTube about the hazards of Hydrazine Rocket Fuel & Nitrogen Tetroxide Oxidizer
https://www.youtube.com/watch?v=bDRKeM9kKxs
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Robotbeat on 07/27/2017 11:06 pm
Geez. Just drop it from a helicopter. Or do what they were planning to do, which is hop using the Superdracos.

Or do none of them, because ITS is a better investment anyway.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: whitelancer64 on 07/27/2017 11:19 pm
Accelerated. Accelerated to terminal velocity, not decelerated.

I'm not sure what it would be for a capsule, but skydivers reach terminal velocity in about 500 meters.

A capsule reentering from orbit would be decelerating. I stand by my word choice.

Except we're talking about a drop test.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Basto on 07/28/2017 12:40 am
Accelerated. Accelerated to terminal velocity, not decelerated.

I'm not sure what it would be for a capsule, but skydivers reach terminal velocity in about 500 meters.

A capsule reentering from orbit would be decelerating. I stand by my word choice.

Except we're talking about a drop test.

Actually I thought we were talking about developing and certifying propulsive landing and the point I was making is a drop test doesn't get you there. 

This back and forth is played out and propulsive landing isn't happening.  So can we go back to discussing things that ARE happening?
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: vaporcobra on 07/28/2017 02:59 am
Has there been any word of what happened with the tethered Dragonfly testing?  Considering that SpaceX was working on the dynamics of landing under power I wonder if they learned something about control stability that led them to decide it wasn't worth pushing forward.

At the ISSRDC, Musk explicitly said that Dragon 2 was the wrong approach to propulsively landing on Mars. Not a perfect corollary, but that basically implies that the same goes for Earth. Recall that the entire purpose of SpaceX is to ensure humans become multiplanetary, something that is explained at the top of every single job posting. I'm sure it could have been done and would have been amazing, but Dragon 2's externally located engines and retractable legs in the heat shield were said to not be the optimal solution, and wasting money on something that will never apply to Mars and isn't even wanted by NASA would be illogical.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: guckyfan on 07/28/2017 07:16 am
At the ISSRDC, Musk explicitly said that Dragon 2 was the wrong approach to propulsively landing on Mars. Not a perfect corollary, but that basically implies that the same goes for Earth.

That IMO refers to scaling up. A giant capsule for 300t payload is not the way to go. It does not mean that Dragon 2 is not feasible for powered landing.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: vaporcobra on 07/28/2017 08:11 am
At the ISSRDC, Musk explicitly said that Dragon 2 was the wrong approach to propulsively landing on Mars. Not a perfect corollary, but that basically implies that the same goes for Earth.

That IMO refers to scaling up. A giant capsule for 300t payload is not the way to go. It does not mean that Dragon 2 is not feasible for powered landing.

Very likely true. It does, however, mean that investing in the expensive process of testing and maturing a propulsively landing capsule design would be almost completely wasted and distract the company and its limited R&D capital from the actual goals that drive it.

While undeniably awesome, remember that SpaceX's tentative schedule for ITS had initial orbital testing planned for as soon as 2020. Red Dragon had already diverted from that schedule and was NET 2020 as of earlier this year. Cancelling propulsive landing dev makes a whole lot of sense.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: whitelancer64 on 07/29/2017 05:46 pm
Accelerated. Accelerated to terminal velocity, not decelerated.

I'm not sure what it would be for a capsule, but skydivers reach terminal velocity in about 500 meters.

A capsule reentering from orbit would be decelerating. I stand by my word choice.

Except we're talking about a drop test.

Actually I thought we were talking about developing and certifying propulsive landing and the point I was making is a drop test doesn't get you there. 

This back and forth is played out and propulsive landing isn't happening.  So can we go back to discussing things that ARE happening?

A drop test would be essential for validating propulsive landing. Of course drop tests can "get you there."

Even if it took a kilometer for the capsule to accelerate to terminal velocity, drop tests can be done from much higher than that. The DragonFly was going to be dropped from 10,000 ft which is about 3 kilometers.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Jcc on 07/30/2017 03:03 pm
People are taking NASA to task and don't know what they are talking about.

Nobody is stepping back and looking at what the issues are.

I don't have inside knowledge about this but it seems easy to figure out.

The issue is qualification of the landing system.  Let me ask how many flights is it taking the Falcon 9 to be qualified as a crew launch vehicle?

And how many flights of a propulsive landing Dragon would be required to qualify it (hover tests don't count)?

Great questions. There was a propulsive landing qualification milestone for SpaceX for a period of time, but that has been removed. We don't know the details of what was proposed to NASA for that, but it must have been at least plausible, but not something that could have been completed prior to the first flights because they were intended for water landings. The current crew contract only calls for a half dozen flights or so by SpaceX and Boeing, so I can see that it would not seem worth the effort to qualify a very new process for only a few uses, while the water landings will have been well tested.

There was also the idea floated to use cargo D2 propulsive landings to gain confidence, but NASA apparently does not want to risk losing returned science results. Qualification tests are done under mission-like conditions but without risking a mission. That would involve launching a D2 to orbit with a dummy cargo, and returning it to land. That involves a cost that NASA doesn't wish to absorb, and neither does SpaceX at this point in time.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Robotbeat on 07/30/2017 03:07 pm
I don't think we can say that NASA was not willing to ever try propulsive landing for cargo flights.

There isn't one thing that led to the decision but a bunch of reasons. At some point, it doesn't make sense to pursue it any longer as opposed to investing in a more important priority, like upper stage reuse and ITS.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Roy_H on 07/30/2017 08:37 pm
I just have to say that I am very disappointed at propulsion landing being terminated. I think precision land landing (runway or pad) is essential for future growth of human space flight. Splashing in the ocean is just too costly, inconvenient, and does not lend itself well for quick re-use. I don't know what the issues are but I hope whatever alternative it available, it will be prioritized. Waiting until 100 passenger ships are available doesn't cut it. When there are more LEO destinations (Bigelow), a land landing craft for small groups of people will be required. Maybe SpaceX is willing to hand that baton over to Dream Chaser.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: joek on 07/30/2017 08:56 pm
... There was a propulsive landing qualification milestone for SpaceX for a period of time, but that has been removed. ...

Please elaborate.  I do not recall--nor can I find--any such stipulations or milestones at an time time for any CCx milestones.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Robotbeat on 07/30/2017 09:03 pm
I just have to say that I am very disappointed at propulsion landing being terminated. I think precision land landing (runway or pad) is essential for future growth of human space flight. Splashing in the ocean is just too costly, inconvenient, and does not lend itself well for quick re-use. I don't know what the issues are but I hope whatever alternative it available, it will be prioritized. Waiting until 100 passenger ships are available doesn't cut it. When there are more LEO destinations (Bigelow), a land landing craft for small groups of people will be required. Maybe SpaceX is willing to hand that baton over to Dream Chaser.
This keeps being repeated.

This critique only makes sense if you think SpaceX is not going to use the resources saved to make investment in a crewed ITS.

So I think people still aren't taking ITS seriously.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: garidan on 07/30/2017 09:06 pm
D2 cargo could have tested landing planning missions with no cargo to return. A minor penality for NASA to gain a new capability

Inviato dal mio MI 5 utilizzando Tapatalk

Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: dror on 07/30/2017 10:06 pm
I just have to say that I am very disappointed at propulsion landing being terminated. I think precision land landing (runway or pad) is essential for future growth of human space flight. Splashing in the ocean is just too costly, inconvenient, and does not lend itself well for quick re-use. I don't know what the issues are but I hope whatever alternative it available, it will be prioritized. Waiting until 100 passenger ships are available doesn't cut it. When there are more LEO destinations (Bigelow), a land landing craft for small groups of people will be required. Maybe SpaceX is willing to hand that baton over to Dream Chaser.
This keeps being repeated.

This critique only makes sense if you think SpaceX is not going to use the resources saved to make investment in a crewed ITS.

So I think people still aren't taking ITS seriously.

Well,
"Obviously it'd be kind of weird if the aliens landed in the ocean with parachutes, we'd be like okay, nothing to fear."
 ;)
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: AncientU on 07/30/2017 10:23 pm
I just have to say that I am very disappointed at propulsion landing being terminated. I think precision land landing (runway or pad) is essential for future growth of human space flight. Splashing in the ocean is just too costly, inconvenient, and does not lend itself well for quick re-use. I don't know what the issues are but I hope whatever alternative it available, it will be prioritized. Waiting until 100 passenger ships are available doesn't cut it. When there are more LEO destinations (Bigelow), a land landing craft for small groups of people will be required. Maybe SpaceX is willing to hand that baton over to Dream Chaser.
This keeps being repeated.

This critique only makes sense if you think SpaceX is not going to use the resources saved to make investment in a crewed ITS.

So I think people still aren't taking ITS seriously.

I do take ITS seriously and am still very disappointed about abandoning propulsive landing on Dragon 2.  To me, it is similar to the situation where SpaceX was confronted by the USAF with all of these demands that they change their way of doing business to become something with which the USAF was comfortable.  EM pushed back as he rightly should have.  What good was it for the USAF to create another company in the image of what they've been whining about as being unsustainable cost-wise?  I believe that NASA was/is reformulating SpaceX/Dragon 2 in their image, and losing out (and denying the achievement to SpaceX) on a significant technological, cost, and even safety improvement.

Is the opposition because of 'not invented here' syndrome or simply the risk that pad landings of Dragon 2 would raise huge questions about the Orion's return to the ocean?  We'll probably never know.  Pure interests of human safety driving the decision are unlikely after the recently completed study of crew on EM-1 was set aside primarily due to insufficient funding and schedule issues.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Jim on 07/31/2017 05:04 am


I believe that NASA was/is reformulating SpaceX/Dragon 2 in their image, and losing out (and denying the achievement to SpaceX) on a significant technological, cost, and even safety improvement.

Is the opposition because of 'not invented here' syndrome or simply the risk that pad landings of Dragon 2 would raise huge questions about the Orion's return to the ocean?  We'll probably never know.  Pure interests of human safety driving the decision are unlikely after the recently completed study of crew on EM-1 was set aside primarily due to insufficient funding and schedule issues.

Wrong again. You have nothing to base such a belief on, except for ingrained bias.

The issue is that Spacex can not sufficiently qualify propulsive landings without flying unmanned flights.  They, SpaceX, does not want to spend the money on qual flights, so they dropped the capability.

It has nothing to with Orion and everything to do with safety. 

Posts like these are getting tiresome
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: guckyfan on 07/31/2017 05:20 am
The issue is that Spacex can not sufficiently qualify propulsive landings without flying unmanned flights.  They, SpaceX, does not want to spend the money on qual flights, so they dropped the capability.

NASA could have provided the opportunity to do these qualification flights on CRS-2 flights. It would have cost them very little to find down cargo they can afford to lose for two flights. Especially as there will be 2 contractors providing down mass. NASA has chosen not to do this and NASA IMO loses out as much or more than SpaceX.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: mikelepage on 07/31/2017 06:50 am
The issue is that Spacex can not sufficiently qualify propulsive landings without flying unmanned flights.  They, SpaceX, does not want to spend the money on qual flights, so they dropped the capability.

NASA could have provided the opportunity to do these qualification flights on CRS-2 flights. It would have cost them very little to find down cargo they can afford to lose for two flights. Especially as there will be 2 contractors providing down mass. NASA has chosen not to do this and NASA IMO loses out as much or more than SpaceX.

Except NASA built a 100 Billion dollar space station to do science.  If the ability to do science in such a laboratory is extremely valuable, the ability to do that science then bring samples back to Earth for analysis is even moreso.  That "down mass" is arguably some of the most valuable cargo in existence.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: guckyfan on 07/31/2017 07:14 am
Except NASA built a 100 Billion dollar space station to do science.  If the ability to do science in such a laboratory is extremely valuable, the ability to do that science then bring samples back to Earth for analysis is even moreso.  That "down mass" is arguably some of the most valuable cargo in existence.

I know. I stated as much. SpaceX brought that back after the Shuttle was terminated. It does not mean that NASA can not afford to stack a Dragon or two with less valuable materials. NASA chose not to and it is their loss as much as it is a loss to SpaceX.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Bynaus on 07/31/2017 07:27 am
I agree it would have been cool to see a Dragon 2 land propulsively, but "cool" should never stand in the way of "making sense", at least not if it costs many millions (and if Elon had to swallow his pride to make that decision, I applaud him for that).

Dragon 2 is a transitional vehicle for SpaceX: they needed it to learn how to build a spacecraft that can carry humans, and to get the funding and expertise from NASA to learn that. Once they have completed their duties to NASA (after building the Dragon 2s for CRS-2 and the Crew contract), they will move on to BFS. No point in spending too much money on something transitional that doesn't significantly inform the BFS. The goal is, and has always been, Mars.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Johnnyhinbos on 07/31/2017 10:44 am
I might suggest that the Dragon 2 be looked at as a purpose built spacecraft with, at most, two very tightly defined roles:

Delivering and safely returning humans (and cargo) to the ISS. That's it.

So why expend time and resources into developing capabilities that aren't needed for those two roles?

SpaceX has evolved greatly since those first designs of the D2 were thought up.

Our understanding and expectations should therefore evolve as well. So instead of going round and round about the loss of D2's propulsive landing ability (it's tedious already), you should get excited about what SpaceX has up their sleeves for what's beyond D2, because that's really worth talking about...
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Lar on 07/31/2017 11:42 am
Except NASA built a 100 Billion dollar space station to do science.  If the ability to do science in such a laboratory is extremely valuable, the ability to do that science then bring samples back to Earth for analysis is even moreso.  That "down mass" is arguably some of the most valuable cargo in existence.

I know. I stated as much. SpaceX brought that back after the Shuttle was terminated. It does not mean that NASA can not afford to stack a Dragon or two with less valuable materials. NASA chose not to and it is their loss as much as it is a loss to SpaceX.

I'm not sure it's *cheap* or *easy* to make downmass wait 6 months or a year beyond the first available CRS that could take it because that mass is being held back to allow for a propulsive landing test. Also I am not sure you can identify a lot of cargo you're willing to risk. If it's going down (and not going down for disposal) it is by definition, important and valuable.

I think some downmass is time sensitive and experiment driven so you're also asking that experiments get shuffled around in the schedule.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: CT Space Guy on 07/31/2017 12:27 pm
There doesn't seem to be a way to test the Dragon's propulsive landing short of an orbital or sub orbital flight on a Falcon.
What?  A drop test would be a fine way to test the landing, easily equivalent to Shuttle ALT flights.

how are you going to drop a spacecraft with hypergols? It is too heavy for helicopter

Wrong, you have no insight on how much a stripped down propulsive landing test article would weigh
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Rocket Science on 07/31/2017 12:33 pm
I've been thinking about the announcement about not approving propulsive landings and I recalled that Orion was considered for landing at the Cape with a steerable parafoil. So my thoughts led to the potential use of a parafoil for Dragon to return for landing on her legs and the use of her her SD to arrest her descent and null any horizontal velocity just prior to touchdown. The trades in a parafoil vs chutes would be interesting...
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Basto on 07/31/2017 12:51 pm
There doesn't seem to be a way to test the Dragon's propulsive landing short of an orbital or sub orbital flight on a Falcon.
What?  A drop test would be a fine way to test the landing, easily equivalent to Shuttle ALT flights.

how are you going to drop a spacecraft with hypergols? It is too heavy for helicopter


Wrong, you have no insight on how much a stripped down propulsive landing test article would weigh


If it doesn't weigh what a loaded D2 weighs then you are not testing the right thing and just wasted time and money.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Robotbeat on 07/31/2017 12:57 pm
There doesn't seem to be a way to test the Dragon's propulsive landing short of an orbital or sub orbital flight on a Falcon.
What?  A drop test would be a fine way to test the landing, easily equivalent to Shuttle ALT flights.

how are you going to drop a spacecraft with hypergols? It is too heavy for helicopter


Wrong, you have no insight on how much a stripped down propulsive landing test article would weigh


If it doesn't weigh what a loaded D2 weighs then you are not testing the right thing and just wasted time and money.
Not really, as you can do incremental tests with a helicopter & heavier tests with other methods.

But this whole thread is boring. SpaceX didn't think it was really worth the cost. It's like Falcon 5.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Jim on 07/31/2017 01:39 pm
There doesn't seem to be a way to test the Dragon's propulsive landing short of an orbital or sub orbital flight on a Falcon.
What?  A drop test would be a fine way to test the landing, easily equivalent to Shuttle ALT flights.

how are you going to drop a spacecraft with hypergols? It is too heavy for helicopter

Wrong, you have no insight on how much a stripped down propulsive landing test article would weigh

Wrong. They don't need a "stripped down propulsive landing test article" or incremental tests.  They need to qualify the actual vehicle.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: envy887 on 07/31/2017 02:15 pm
...SpaceX didn't think it was really worth the cost. It's like Falcon 5.

Unlike Falcon 5, SpaceX doesn't have a fully funded, clearly defined replacement/upgrade that's late in development and/or early in manufacture.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: cppetrie on 07/31/2017 03:06 pm
...SpaceX didn't think it was really worth the cost. It's like Falcon 5.

Unlike Falcon 5, SpaceX doesn't have a fully funded, clearly defined replacement/upgrade that's late in development and/or early in manufacture.
That we know of...

We have no idea how far along in development the new ITSy vehicle is nor how well funded its development is. We know they don't have contracts for it's use. That doesn't mean they haven't fully planned for its funding using internal funds or other sources of private funding.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: whitelancer64 on 07/31/2017 04:38 pm
There doesn't seem to be a way to test the Dragon's propulsive landing short of an orbital or sub orbital flight on a Falcon.
What?  A drop test would be a fine way to test the landing, easily equivalent to Shuttle ALT flights.

how are you going to drop a spacecraft with hypergols? It is too heavy for helicopter

Wrong, you have no insight on how much a stripped down propulsive landing test article would weigh

If it doesn't weigh what a loaded D2 weighs then you are not testing the right thing and just wasted time and money.

The Sikorsky CH-53E Super Stallion, the largest heavy-lift helicopter in the US military, can lift 30,000 lb internally and 36,000 lb externally, and has a flight service ceiling of over 15,000 feet.

A Boeing CH-47 Chinook can lift 24,000 lb and has a flight service ceiling of 20,000 feet.

As far as I know, Dragon v2 is supposed to be somewhere in the range of 17,000 lb when fully fueled.

Such helicopters could easily do a drop test of a full scale test article or a flight article, for propulsive landing tests.

SpaceX has done drop tests for the Dragon's parachutes using an Erickson S-64F Air-Crane helicopter.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: dwheeler on 07/31/2017 05:01 pm
There doesn't seem to be a way to test the Dragon's propulsive landing short of an orbital or sub orbital flight on a Falcon.
What?  A drop test would be a fine way to test the landing, easily equivalent to Shuttle ALT flights.

how are you going to drop a spacecraft with hypergols? It is too heavy for helicopter

Wrong, you have no insight on how much a stripped down propulsive landing test article would weigh

If it doesn't weigh what a loaded D2 weighs then you are not testing the right thing and just wasted time and money.

The Sikorsky CH-53E Super Stallion, the largest heavy-lift helicopter in the US military, can lift 30,000 lb internally and 36,000 lb externally, and has a flight service ceiling of over 15,000 feet.

A Boeing CH-47 Chinook can lift 24,000 lb and has a flight service ceiling of 20,000 feet.

<snip>
Helicopters generally can't take their max payloads anywhere near their service ceilings...
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Basto on 07/31/2017 05:07 pm
There doesn't seem to be a way to test the Dragon's propulsive landing short of an orbital or sub orbital flight on a Falcon.
What?  A drop test would be a fine way to test the landing, easily equivalent to Shuttle ALT flights.

how are you going to drop a spacecraft with hypergols? It is too heavy for helicopter

Wrong, you have no insight on how much a stripped down propulsive landing test article would weigh

If it doesn't weigh what a loaded D2 weighs then you are not testing the right thing and just wasted time and money.

The Sikorsky CH-53E Super Stallion, the largest heavy-lift helicopter in the US military, can lift 30,000 lb internally and 36,000 lb externally, and has a flight service ceiling of over 15,000 feet.

A Boeing CH-47 Chinook can lift 24,000 lb and has a flight service ceiling of 20,000 feet.

As far as I know, Dragon v2 is supposed to be somewhere in the range of 17,000 lb when fully fueled.

Such helicopters could easily do a drop test of a full scale test article or a flight article, for propulsive landing tests.

SpaceX has done drop tests for the Dragon's parachutes using an Erickson S-64F Air-Crane helicopter.

Whether a helicopter can lift a Dragon 2 and drop it at altitude is not really the issue... propulsive landing tests and propulsive landing certification are not the same thing.  Without full up launches to certify the safe landing NASA is not going to let you risk crew and cargo.  All of which add time and money, time and money that SpaceX decided they did not want to spend.  Can we let this go now?  I am pretty sure you are not going to get SpaceX to change their collective mind.


Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: intrepidpursuit on 07/31/2017 05:59 pm
Is it really on topic to be discussing how SpaceX could have tested a canceled capability? Two pages in this gets really boring.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: whitelancer64 on 07/31/2017 06:00 pm
There doesn't seem to be a way to test the Dragon's propulsive landing short of an orbital or sub orbital flight on a Falcon.
What?  A drop test would be a fine way to test the landing, easily equivalent to Shuttle ALT flights.

how are you going to drop a spacecraft with hypergols? It is too heavy for helicopter

Wrong, you have no insight on how much a stripped down propulsive landing test article would weigh

If it doesn't weigh what a loaded D2 weighs then you are not testing the right thing and just wasted time and money.

The Sikorsky CH-53E Super Stallion, the largest heavy-lift helicopter in the US military, can lift 30,000 lb internally and 36,000 lb externally, and has a flight service ceiling of over 15,000 feet.

A Boeing CH-47 Chinook can lift 24,000 lb and has a flight service ceiling of 20,000 feet.

As far as I know, Dragon v2 is supposed to be somewhere in the range of 17,000 lb when fully fueled.

Such helicopters could easily do a drop test of a full scale test article or a flight article, for propulsive landing tests.

SpaceX has done drop tests for the Dragon's parachutes using an Erickson S-64F Air-Crane helicopter.

Whether a helicopter can lift a Dragon 2 and drop it at altitude is not really the issue... propulsive landing tests and propulsive landing certification are not the same thing.  Without full up launches to certify the safe landing NASA is not going to let you risk crew and cargo.  All of which add time and money, time and money that SpaceX decided they did not want to spend.  Can we let this go now?  I am pretty sure you are not going to get SpaceX to change their collective mind.

The point isn't to change SpaceX's mind.

The point is that drop tests for propulsive landing is possible.

Certainly an orbital reentry and propulsive landing would have been required for final validation, the Dragon v2's parachutes have a similar validation milestone that will be completed on the uncrewed flight test's reentry.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Space Ghost 1962 on 07/31/2017 07:01 pm
Barking up the wrong trees.

SX is moving on from Dragon development after crew/cargo Dragons.

And if you were to "needfully" do anything, it would be Soyuz-styled parachute then brief touchdown burn. That would give you landings w/o salt intrusion.

But you wouldn't have the grand Musk vision, nor would you have a clear agreement on a sensible means to qualify such, within the scope of the Dragon program.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Jim on 07/31/2017 08:00 pm
There doesn't seem to be a way to test the Dragon's propulsive landing short of an orbital or sub orbital flight on a Falcon.
What?  A drop test would be a fine way to test the landing, easily equivalent to Shuttle ALT flights.

how are you going to drop a spacecraft with hypergols? It is too heavy for helicopter

Wrong, you have no insight on how much a stripped down propulsive landing test article would weigh

If it doesn't weigh what a loaded D2 weighs then you are not testing the right thing and just wasted time and money.

The Sikorsky CH-53E Super Stallion, the largest heavy-lift helicopter in the US military, can lift 30,000 lb internally and 36,000 lb externally, and has a flight service ceiling of over 15,000 feet.

A Boeing CH-47 Chinook can lift 24,000 lb and has a flight service ceiling of 20,000 feet.

As far as I know, Dragon v2 is supposed to be somewhere in the range of 17,000 lb when fully fueled.

Such helicopters could easily do a drop test of a full scale test article or a flight article, for propulsive landing tests.

SpaceX has done drop tests for the Dragon's parachutes using an Erickson S-64F Air-Crane helicopter.

Dragon V2 is much heavier than 17klb, closer to 25klb and even at 17klb there is no helicopter that can lift it to a sufficient drop altitude.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: whitelancer64 on 07/31/2017 08:33 pm

Dragon V2 is much heavier than 17klb, closer to 25klb and even at 17klb there is no helicopter that can lift it to a sufficient drop altitude.

I'd like to know if you have a source for that, given that the pad abort test article was about 14,000 lb with 3,000 lb of fuel, per the DragonFly and Pad Abort Environmental Assessments.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Rocket Science on 07/31/2017 08:44 pm
Why do you need a helicopter? Check the dimensions, get permission and drop it out of any military airlift command (MAC) suitable and available, C-5, C-17 etc...
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Oli on 07/31/2017 08:47 pm
Without full up launches to certify the safe landing NASA is not going to let you risk crew and cargo.

Is there any evidence whatsoever that NASA didn't want to risk cargo respectively that NASA changed its requirements in that regard since SpaceX won the contract?
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: envy887 on 07/31/2017 08:49 pm
Why do you need a helicopter? Check the dimensions, get permission and drop it out of any military airlift command (MAC) suitable and available, C-5, C-17 etc...

SpaceX has done Dragon parachute drop tests from cargo planes, I'm sure they at least considered that.

It doesn't really matter what the cheapest solution is; nobody was willing (at this time) to pay to reach that solution. So it's shelved.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Jim on 07/31/2017 08:57 pm

Dragon V2 is much heavier than 17klb, closer to 25klb and even at 17klb there is no helicopter that can lift it to a sufficient drop altitude.

I'd like to know if you have a source for that, given that the pad abort test article was about 14,000 lb with 3,000 lb of fuel, per the DragonFly and Pad Abort Environmental Assessments.

Again, doesn't matter, helicopters can't lift 17klb enough anyways.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Jim on 07/31/2017 08:58 pm
Why do you need a helicopter? Check the dimensions, get permission and drop it out of any military airlift command (MAC) suitable and available, C-5, C-17 etc...

read up thread about hypergols
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Rocket Science on 07/31/2017 09:02 pm
Why do you need a helicopter? Check the dimensions, get permission and drop it out of any military airlift command (MAC) suitable and available, C-5, C-17 etc...

read up thread about hypergols
Thanks Jim!
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: whitelancer64 on 07/31/2017 10:47 pm

Dragon V2 is much heavier than 17klb, closer to 25klb and even at 17klb there is no helicopter that can lift it to a sufficient drop altitude.

I'd like to know if you have a source for that, given that the pad abort test article was about 14,000 lb with 3,000 lb of fuel, per the DragonFly and Pad Abort Environmental Assessments.

Again, doesn't matter, helicopters can't lift 17klb enough anyways.

SpaceX has done drop tests for the Dragon's parachutes using an Erickson S-64F Air-Crane helicopter. The parachute test article was 12,000 lb. Those tests went up to at least 8,000 feet.

https://www.nasa.gov/content/nasa-commercial-crew-partner-spacex-tests-dragon-parachute-system/

The current world record for helicopter altitude with a 15,000 kg payload (33,000 lb) is 5,600 meters (18,300 feet), with a Russian Mi-26 heavy lift helicopter.

https://www.thisdayinaviation.com/tag/world-record-for-altitude-with-a-15000-kilogram-payload/
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Jim on 08/01/2017 12:15 am
My point still stands.   8000 feet isn't high enough and a Russian copter is a non starter
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: dorkmo on 08/01/2017 12:37 am
i know this discussion is a waste of time... but how much would it cost them to launch it on top of a first stage? vs renting a non-existing helicopter?

could they put a dummy second stage on so that they can use the tel?
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Robotbeat on 08/01/2017 12:41 am
Renting one of the few civilian Mi-26es might cost a few million (transport costs), so probably about ten times more expensive to put a Dragon on top of a booster instead.

OR they just focus on getting Dragon crew to ISS and put any extra money into ITS.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Jcc on 08/01/2017 01:41 am
... There was a propulsive landing qualification milestone for SpaceX for a period of time, but that has been removed. ...

Please elaborate.  I do not recall--nor can I find--any such stipulations or milestones at an time time for any CCx milestones.

It was here:
http://forum.nasaspaceflight.com/index.php?topic=37802.msg1537649#msg1537649
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: envy887 on 08/01/2017 03:34 am
In flight abort remains to be done.

Is that going to use an upper stage?
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: garidan on 08/01/2017 03:50 am
I don't want to bother everyone, but if i remember correctly Cignus costs more than Dragon to NASA, and downmass was almost a free bonus.
If the price adjusted to the available payload is equal (I don't know) the simpler solution to qualify Dragon 2 for powered landings was to plan some more cargo launch with no or garbage downmass, but regular and valuable upmass.

The outcome for NASA would have bean, at least, a reusable cargo Dragon 2 with not so much refurbishment needed.

It makes sense only if NASA is interested in getting cheaper to ISS, it sounds like it's not.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: cppetrie on 08/01/2017 04:09 am
I don't want to bother everyone, but if i remember correctly Cignus costs more than Dragon to NASA, and downmass was almost a free bonus.
If the price adjusted to the available payload is equal (I don't know) the simpler solution to qualify Dragon 2 for powered landings was to plan some more cargo launch with no or garbage downmass, but regular and valuable upmass.

The outcome for NASA would have bean, at least, a reusable cargo Dragon 2 with not so much refurbishment needed.

It makes sense only if NASA is interested in getting cheaper to ISS, it sounds like it's not.
It's a fixed price contract. Cheaper refurbishment only increases SpaceX profit unless expected cost savings from cheaper refurbishment were built into the contract price, which seems very unlikely. It would take a very long view, one that extends beyond the planned life of the ISS, for NASA to see the savings from the propulsive landing capability.

It clearly didn't make sense on the whole when the parties looked at it, which is why it's gone for now at least.

The horse is dead, can we stop beating it now and move on?
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: vanoord on 08/01/2017 07:56 am
In flight abort remains to be done.

Is that going to use an upper stage?

Shouldn't have to, as abort will be tested at MaxQ, which is during first stage ascent?

IIRC there's a 'Falcon 3' core at Vandenberg which was built for landing tests, then re-purposed to do the abort test but is now surplus to requirements (it's based on F9 1.1 and may not be compatible with a TEL set-up for F9 FT) - but it gives an indication, I guess, that the abort test will be carried out atop a used first stage flying on three engines only.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Jet Black on 08/01/2017 11:27 am
Barking up the wrong trees.

SX is moving on from Dragon development after crew/cargo Dragons.


Absolutely. I have to confess I'm looking forward to them doing deliveries to the ISS in the mini-ITS.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Jim on 08/01/2017 01:40 pm
Barking up the wrong trees.

SX is moving on from Dragon development after crew/cargo Dragons.


Absolutely. I have to confess I'm looking forward to them doing deliveries to the ISS in the mini-ITS.

ISS won't be around and the mini ITS would be too big to approach the ISS
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: JBF on 08/01/2017 02:24 pm
Barking up the wrong trees.

SX is moving on from Dragon development after crew/cargo Dragons.


Absolutely. I have to confess I'm looking forward to them doing deliveries to the ISS in the mini-ITS.

ISS won't be around and the mini ITS would be too big to approach the ISS

Is size an issue for docking procedures?  The shuttle out massed the ISS during much of the initial construction.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: rsdavis9 on 08/01/2017 03:12 pm
Whats the mass of the shuttle?
I would think that with all those bricks the shuttle would be pretty heavy.
The ITSy is lightweight pica-x and composites and engines.

EDIT:
shuttle orbiter is 68 tonnes empty
max takeoff 109 tonnes
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: whitelancer64 on 08/01/2017 03:18 pm
Barking up the wrong trees.

SX is moving on from Dragon development after crew/cargo Dragons.


Absolutely. I have to confess I'm looking forward to them doing deliveries to the ISS in the mini-ITS.

Assuming it flies by 2024, and the ISS isn't deorbited by 2024.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: whitelancer64 on 08/01/2017 03:19 pm
Barking up the wrong trees.

SX is moving on from Dragon development after crew/cargo Dragons.


Absolutely. I have to confess I'm looking forward to them doing deliveries to the ISS in the mini-ITS.

ISS won't be around and the mini ITS would be too big to approach the ISS

Is size an issue for docking procedures?  The shuttle out massed the ISS during much of the initial construction.

Clearance of ISS structures (like solar arrays) would be the issue.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Jim on 08/01/2017 03:28 pm
Whats the mass of the shuttle?
I would think that with all those bricks the shuttle would be pretty heavy.
The ITSy is lightweight pica-x and composites and engines.

EDIT:
shuttle orbiter is 68 tonnes empty
max takeoff 109 tonnes

Shuttle tiles are lighter than PICA
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Jim on 08/01/2017 03:30 pm
Barking up the wrong trees.

SX is moving on from Dragon development after crew/cargo Dragons.


Absolutely. I have to confess I'm looking forward to them doing deliveries to the ISS in the mini-ITS.

ISS won't be around and the mini ITS would be too big to approach the ISS

Is size an issue for docking procedures?  The shuttle out massed the ISS during much of the initial construction.

Mini ITS is 9 meters in diameter, would be more massive than shuttle.  Its thrusters would be stronger than shuttle
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: envy887 on 08/01/2017 04:31 pm
Whats the mass of the shuttle?
I would think that with all those bricks the shuttle would be pretty heavy.
The ITSy is lightweight pica-x and composites and engines.

EDIT:
shuttle orbiter is 68 tonnes empty
max takeoff 109 tonnes

A fully loaded orbiter was up to 125 tonnes, though slightly less than that at ISS. A 9 meter ITS could only put about 150 tonnes total to ISS orbit, including the mass of the upper stage. However, it could be as light as 75 tonnes (possibly less) and still approach ISS with much more payload than any current vehicle can carry.

A subscale BFS itself will be really fluffy and not all that large. So whether it's more massive than a orbiter depends mostly on what its payload is.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: JBF on 08/01/2017 04:42 pm
In any case I think Jim's point was it's not directly, the mass or size.  It's how big of an impingement the ITS's larger thrusters would have on the ISS.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Herb Schaltegger on 08/01/2017 05:05 pm
In any case I think Jim's point was it's not directly, the mass or size.  It's how big of an impingement the ITS's larger thrusters would have on the ISS.
Indeed. Plume impingement and external contamination constraints are rarely considered by people who didn’t design the thing.  ;)

And just FYI, those constraints are tighter than folks realize.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Semmel on 08/01/2017 07:53 pm
In any case I think Jim's point was it's not directly, the mass or size.  It's how big of an impingement the ITS's larger thrusters would have on the ISS.
Indeed. Plume impingement and external contamination constraints are rarely considered by people who didn’t design the thing.  ;)

And just FYI, those constraints are tighter than folks realize.
If he meant thrust impingement, why didn't he say so? I don't think that's what he meant. If he says it's too large,  he means physically too large or if you want to stretch it, too much mass.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Negan on 08/01/2017 08:06 pm
Just put a Dragon or two inside the Mini-ITS have them dock with the station.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: rsdavis9 on 08/01/2017 09:03 pm
A very long inflatable tube like you see in the movies...
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Lar on 08/01/2017 09:29 pm
Pretty sure that ITS docking with ISS isn't about Dragon 2.

Wandering! C'mon guys.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Herb Schaltegger on 08/01/2017 09:41 pm
In any case I think Jim's point was it's not directly, the mass or size.  It's how big of an impingement the ITS's larger thrusters would have on the ISS.
Indeed. Plume impingement and external contamination constraints are rarely considered by people who didn’t design the thing.  ;)

And just FYI, those constraints are tighter than folks realize.
If he meant thrust impingement, why didn't he say so? I don't think that's what he meant. If he says it's too large,  he means physically too large or if you want to stretch it, too much mass.

He probably meant "all of the above" in his usual, Jim-style brevity. Too physically large for clearance to dock or berth, thrusters necessary nudge that physical size and maintain attitude control will have huge impingement volumes and deposit hypergol residues and unreacted prop molecules all over the station exterior, which take time to dissipate and off-gas from the surfaces they might adhere to, and even if you could physically mate the two, attitude control of the stack would be ridiculously complicated, with a huge drag profile, odd oscillation modes and forces between ISS components ...

But Lar is absolutely right. This isn't Dragon 2, which will have none of these concerns.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Negan on 08/01/2017 09:53 pm
He probably meant "all of the above" in his usual, Jim-style brevity. Too physically large for clearance to dock or berth, thrusters necessary nudge that physical size and maintain attitude control will have huge impingement volumes and deposit hypergol residues and unreacted prop molecules all over the station exterior, which take time to dissipate and off-gas from the surfaces they might adhere to, and even if you could physically mate the two, attitude control of the stack would be ridiculously complicated, with a huge drag profile, odd oscillation modes and forces between ISS components ...

Off topic sure, but I just learned a whole lot from your post. Not sure why that's a bad thing.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: deruch on 08/06/2017 02:23 am
Not to resurrect a dead horse, but if SpaceX is truly giving up on powered landings with the Dragon 2 why did they just (last week) renew their FAA Experimental Permit for DragonFly testing(.pdf) (https://www.faa.gov/about/office_org/headquarters_offices/ast/licenses_permits/media/Final%20Dragonfly%20Experimental%20Permit%20and%20Orders%20EP-15-011%207-27-2017.pdf)?  Previous version expired at the end of July, now renewed for another year til 2018.

Note, this testing permit is still strictly for low altitude testing.  Ceiling is still 80ft above ground level.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Herb Schaltegger on 08/06/2017 02:32 am
Not to resurrect a dead horse, but if SpaceX is truly giving up on powered landings with the Dragon 2 why did they just (last week) renew their FAA Experimental Permit for DragonFly testing(.pdf) (https://www.faa.gov/about/office_org/headquarters_offices/ast/licenses_permits/media/Final%20Dragonfly%20Experimental%20Permit%20and%20Orders%20EP-15-011%207-27-2017.pdf)?  Previous version expired at the end of July, now renewed for another year til 2018.

Note, this testing permit is still strictly for low altitude testing.  Ceiling is still 80ft above ground level.

Having some experience with regulatory bodies, my guess is that it's easier (and cheaper by far) to renew an existing permit than to allow it to lapse and get a new one at some point in the future if plans change.

It's also possible that, despite the change of plans with regard to Dragon 2, there are lessons to be learned in a low-intensity R&D effort that can inform the design of future vehicles, perhaps for notional use on the Moon or Mars.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Robotbeat on 08/06/2017 03:01 am
I wonder if the same permit could be used for a Grasshopper-like test of an ITS-like vehicle?
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: docmordrid on 08/06/2017 03:54 am
Doubt it unless the new vehicle is described in the amended permit, as the DragonFly vehicle was in the original permit.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Robotbeat on 08/06/2017 03:58 am
Doubt it unless the new vehicle is described in the amended permit, as the FireFly vehicle was in the original permit.
I wonder if they wish to try out launch cradle tests, perhaps even with the FireFly vehicle.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: docmordrid on 08/06/2017 04:58 am
ISTM pre-ITS/ITSy cradle tests would be done using a stage shaped bottom thrusting form factor, not a side-thrusting capsule.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: obi-wan on 08/08/2017 05:08 pm
Has there ever been any official (or otherwise definitive) answer to the following questions? (Ideally with a reference, this is for a paper and I can't use speculation.)

(1) What is the operational (launch) mass of a Dragon 2?

(2) Given the requirement of separating the trunk in a launch abort, is there any capability to carry trunk cargo on a crewed Dragon 2 mission? If so, what is the mass limit of that external cargo?

Thanks!
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: OxCartMark on 08/14/2017 03:18 am
Just waded through the last 5 or so pages.  The thing that I don't see mentioned is the apparent connection between cancellation of D2 propulsive landing and the (going back ~2 years) vast lack of news on Dragon Fly testing.  We had one video showing a ~5 second hover fairly early on in the stated Dragon Fly test period then nothing (that I'm aware of) more was heard of the DF program.  I'm leaning toward thinking that hope for D2 propulsive landings faded at that point, or that there were difficult development issues exposed then that they had hoped to be able to overcome but now in 2017 with deadlines and budget caps within sight it doesn't make sense to SpaceX and their NASA oversighters to pursue propulsive landing on D2.

Potential issues that could have been found in the first Dragon Fly test(s):
- Oblitorous levels of cabin noise
- Engine startup timing differences and thrust transients combined with line of thrust significantly not intersecting CG caused a potentially not always stable directional control problem.  Theorospeculating more on this, for the launch abort test we saw they may have remained clamped to the 2nd stage for a few hundred milliseconds until all engines were on the same page, an opportunity that is not available with a landing Dragon. And, the directional control 'twitchiness' during he abort test was not as great as it would be in a landing because of the attached trunk.

Something along this line also fits with Musk's statement that propulsive landing is still in the long term plan but the D2 method of propulsive landing was um, kind of not so good (paraphrasing from potentially inaccurate memory).  Perhaps the change going forward in the pursuit of propulsive landing is that the engines need to be under the thing as they are on ITS  ((yes, I know under isn't a great position on a capsule)).
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: old_sellsword on 08/14/2017 04:21 pm
NASA TV snuck in this shot of Dragon 2 construction during a "Commercial Partners" montage in the CRS-12 webcast.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: russianhalo117 on 08/14/2017 04:52 pm
NASA TV snuck in this shot of Dragon 2 construction during a "Commercial Partners" montage in the CRS-12 webcast.
Is that a honeycomb composite trunk or pure composite barrel with honeycomb composite fins?? The original v1 trunk had aluminum isogrid panels.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: old_sellsword on 08/15/2017 01:53 am
NASA TV snuck in this shot of Dragon 2 construction during a "Commercial Partners" montage in the CRS-12 webcast.
Is that a honeycomb composite trunk or pure composite barrel with honeycomb composite fins?? The original v1 trunk had aluminum isogrid panels.

Someone on r/SpaceX suggested it could just be anodized Aluminum considering the lack of CF texture and the bolted-on fins.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Jcc on 08/15/2017 02:25 am
A bit of news I think from the CRS-12 post launch press conference, Dan Hartman said NASA is looking into accelerating the use of the cargo Dragon 2 for later CRS-1 contract missions.

Put together with statements that CRS-12 was the last new Dragon 1 and future missions will be refurbished, there may be some new Dragon 2s in the mix as well.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: adrianwyard on 08/15/2017 02:58 am
Just waded through the last 5 or so pages.  The thing that I don't see mentioned is the apparent connection between cancellation of D2 propulsive landing and the (going back ~2 years) vast lack of news on Dragon Fly testing.  We had one video showing a ~5 second hover fairly early on in the stated Dragon Fly test period then nothing (that I'm aware of) more was heard of the DF program.  I'm leaning toward thinking that hope for D2 propulsive landings faded at that point, or that there were difficult development issues exposed then that they had hoped to be able to overcome but now in 2017 with deadlines and budget caps within sight it doesn't make sense to SpaceX and their NASA oversighters to pursue propulsive landing on D2.

Potential issues that could have been found in the first Dragon Fly test(s):
- Oblitorous levels of cabin noise
- Engine startup timing differences and thrust transients combined with line of thrust significantly not intersecting CG caused a potentially not always stable directional control problem.  Theorospeculating more on this, for the launch abort test we saw they may have remained clamped to the 2nd stage for a few hundred milliseconds until all engines were on the same page, an opportunity that is not available with a landing Dragon. And, the directional control 'twitchiness' during he abort test was not as great as it would be in a landing because of the attached trunk.

...
Another challenge might have been the quantity of residual NTO and MMH left in the area after landing:
https://www.youtube.com/watch?v=07Pm8ZY0XJI

Probably smart to to wait until that nastiness blows away before opening the hatch. They could bring in blowers, or require people to exit suited up, but I bet neither is desirable. That complexity/potential danger might have been enough to tip the balance to all water landings.

(I bet it is very noisy, and stability could be tricky, but we do know that both are acceptable for the abort case.)

Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: yg1968 on 08/15/2017 02:46 pm
One of the interesting things that was said yesterday at the post-launch conference is that SpaceX is looking at using cargo Dragon2 prior to using it for crewed Dragon2 in order to test it out. That would make a lot of sense.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: abaddon on 08/15/2017 02:50 pm
One of the interesting things that was said yesterday at the post-launch conference is that SpaceX is looking at using cargo Dragon2 prior to using it for crewed Dragon2 in order to test it out. That would make a lot of sense.
I don't recall the exact wording, but my impression was that they are looking at it post-certification, so after the initial crewed test flight.  I imagine how quickly and easily SpaceX can refurbish a Crew Dragon will play into how that shakes out.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: rockets4life97 on 08/15/2017 05:02 pm
If I remember right Dragon 2 has a bigger volume than Dragon 1. So, from NASA's perspective, getting more volume on a CRS flight by flying Dragon 2's would be a bonus.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: yg1968 on 08/15/2017 05:56 pm
This article talks about it:

http://www.teslarati.com/spacex-nasa-relationship-sponsored-falcon-9-reuse-discussion/

Quote
Hartman said that he was hopeful SpaceX would be able to operationally begin flying crew to the ISS as soon as FY2019, which begins October 1, 2018. However, he suggested that NASA was interested in SpaceX flying Dragon 2 solely with cargo “to get some more flights under its belt” ahead of “routine” crew transport.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: gongora on 08/15/2017 06:00 pm
This article talks about it:

http://www.teslarati.com/spacex-nasa-relationship-sponsored-falcon-9-reuse-discussion/

Quote
However, he suggested that NASA was interested in SpaceX flying Dragon 2 solely with cargo “to get some more flights under its belt” ahead of “routine” crew transport.

Routine crew transport (post certification missions) is probably around Q2 2019.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: yg1968 on 08/15/2017 06:09 pm
This article talks about it:

http://www.teslarati.com/spacex-nasa-relationship-sponsored-falcon-9-reuse-discussion/

Quote
Hartman said that he was hopeful SpaceX would be able to operationally begin flying crew to the ISS as soon as FY2019, which begins October 1, 2018. However, he suggested that NASA was interested in SpaceX flying Dragon 2 solely with cargo “to get some more flights under its belt” ahead of “routine” crew transport.

Routine crew transport (post certification missions) is probably around Q2 2019.

Ahead means before. So it could be anytime before routine flights start. But ideally, it should be before the first crewed test flight since that flight will carry two NASA astronauts. Perhaps that is why he said that he was hopeful that post-certification flights for SpaceX would start in FY 2019 (which starts on October 1, 2018). It could be that NASA asked SpaceX to provide another demo (cargo) Dragon2 flight through CRS prior to starting crewed flights.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: rockets4life97 on 08/15/2017 06:27 pm
It could be that NASA asked SpaceX to provide another demo (cargo) Dragon2 flight through CRS prior to starting crewed flights.

I'd guess it goes the other way with SpaceX asking NASA to speed the transition to Dragon 2s (and btw add more money to the CRS-1 contract -- remember SpaceX has a higher price per mission under CRS-2 than CRS-1).
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: gongora on 08/15/2017 06:30 pm
This article talks about it:

http://www.teslarati.com/spacex-nasa-relationship-sponsored-falcon-9-reuse-discussion/

Quote
Hartman said that he was hopeful SpaceX would be able to operationally begin flying crew to the ISS as soon as FY2019, which begins October 1, 2018. However, he suggested that NASA was interested in SpaceX flying Dragon 2 solely with cargo “to get some more flights under its belt” ahead of “routine” crew transport.

Routine crew transport (post certification missions) is probably around Q2 2019.

Ahead means before. So it could be anytime before routine flights start. But ideally, it should be before the first crewed test flight since that flight will carry two NASA astronauts. Perhaps that is why he said that he was hopeful that post-certification flights for SpaceX would start in FY 2019 (which starts on October 1, 2018). It could be that NASA asked SpaceX to provide another demo (cargo) Dragon2 flight through CRS prior to starting crewed flights.

Quote
We're very eager in the FY19 period to see a Commercial Crew Dragon come to the station on a routine basis.  I imagine you'll see us flying some Dragon 2 version to support cargo, ahead of or to get some more flights under its belt on Dragon 2 maybe even before we step up to the serious crew rotations that we need to occur on the ISS.  So we're working with SpaceX right now to see when that conversion time is to go from Dragon 1 configuration we saw today into a Dragon 2, and again just to get more run time on that vehicle, so those discussions are ongoing.

He doesn't even remotely hint at flying a cargo Dragon 2 before the manned test flight.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Kansan52 on 08/15/2017 06:33 pm
I've lost track.

Earlier discussions seemed to rule out D2 for cargo runs since the docking port is a smaller opening than the berthing port and D2 could not be berthed.

So the plan going forward would be bulky supplies on D1 and smaller items on D2? Or do we know anything at all.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: gongora on 08/15/2017 06:58 pm
I've lost track.

Earlier discussions seemed to rule out D2 for cargo runs since the docking port is a smaller opening than the berthing port and D2 could not be berthed.

So the plan going forward would be bulky supplies on D1 and smaller items on D2? Or do we know anything at all.

See this NASA presentation from December 2016:
https://forum.nasaspaceflight.com/index.php?topic=41016.msg1623758#msg1623758 (https://forum.nasaspaceflight.com/index.php?topic=41016.msg1623758#msg1623758)

Obviously the propulsive landing part has been dropped, but docked Dragon 2 is the initial configuration.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: meberbs on 08/15/2017 07:32 pm
Ahead means before. So it could be anytime before routine flights start. But ideally, it should be before the first crewed test flight since that flight will carry two NASA astronauts. Perhaps that is why he said that he was hopeful that post-certification flights for SpaceX would start in FY 2019 (which starts on October 1, 2018). It could be that NASA asked SpaceX to provide another demo (cargo) Dragon2 flight through CRS prior to starting crewed flights.
Based on the details of the full quote gongora posted, it may be that he doesn't necessarily count the first operational flights under the contract as "serious crew rotations." After all, the first couple operational flights are planned to overlap with 2 Soyuz, and not have a full crew.

https://www.nasaspaceflight.com/2017/02/commercial-rotation-us-segment-crew-increase-early/

Under this interpretation, depending on the order of SpaceX and Boeing flights, they could get 1 or 2 cargo Dragon 2 missions in before a fully crewed Dragon 2 flight if the pull some of the CRS 2 missions ahead of the last couple CRS 1 missions.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Kansan52 on 08/15/2017 08:57 pm
Obviously the propulsive landing part has been dropped, but docked Dragon 2 is the initial configuration.

Thanks!!
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: yg1968 on 08/15/2017 08:58 pm
Quote from: Hartman
We're very eager in the FY19 period to see a Commercial Crew Dragon come to the station on a routine basis.  I imagine you'll see us flying some Dragon 2 version to support cargo, ahead of or to get some more flights under its belt on Dragon 2 maybe even before we step up to the serious crew rotations that we need to occur on the ISS.  So we're working with SpaceX right now to see when that conversion time is to go from Dragon 1 configuration we saw today into a Dragon 2, and again just to get more run time on that vehicle, so those discussions are ongoing.

He doesn't even remotely hint at flying a cargo Dragon 2 before the manned test flight.

Thanks for the full quote. The full quote is indeed much clearer.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: guckyfan on 08/15/2017 09:01 pm
Would that mean they give the first Crew flight to Boeing, even if SpaceX does complete their milestones first?
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: deruch on 08/18/2017 07:54 am
It seems to me that he is talking about the possibility of flying a Dragon 2 cargo mission in between DM-2 and PCM-1X (SpaceX's 1st post certification mission; non-official mission notation). 
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: tvg98 on 08/18/2017 08:40 pm
Quote
I have it on good authority (the goodest) that the Orion parachutes are identical to the Dragon parachutes. Indistinguishable. Both spacecraft are using the same model and vendor.

https://www.reddit.com/r/spaceflight/comments/6ueula/yes_it_really_has_taken_nasa_11_years_to_develop/dls6qsi/ (https://www.reddit.com/r/spaceflight/comments/6ueula/yes_it_really_has_taken_nasa_11_years_to_develop/dls6qsi/)

Can anyone verify this? (Pardon me if this was already known if it is true).
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: whitelancer64 on 08/18/2017 09:10 pm
Quote
I have it on good authority (the goodest) that the Orion parachutes are identical to the Dragon parachutes. Indistinguishable. Both spacecraft are using the same model and vendor.

https://www.reddit.com/r/spaceflight/comments/6ueula/yes_it_really_has_taken_nasa_11_years_to_develop/dls6qsi/ (https://www.reddit.com/r/spaceflight/comments/6ueula/yes_it_really_has_taken_nasa_11_years_to_develop/dls6qsi/)

Can anyone verify this? (Pardon me if this was already known if it is true).

Could be true. Some googling tells me that both Orion and Dragon use main parachutes 116 ft. (35.35 meters) in diameter. Not sure why Dragon v2 would use 4 when Orion only uses 3, though... Orion is quite a bit heavier, right?

"SpaceX uses parachutes that Airborne based on the Orion landing system to land its Dragon capsule, which has been flying supplies to the International Space Station (ISS) since 2012."

https://spinoff.nasa.gov/Spinoff2017/t_3.html

Side note, Blue Origin also uses parachutes made by Airborne, but they are 85.6 ft. (26 meters) in diameter.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: whitelancer64 on 08/18/2017 09:35 pm
Quote
I have it on good authority (the goodest) that the Orion parachutes are identical to the Dragon parachutes. Indistinguishable. Both spacecraft are using the same model and vendor.

https://www.reddit.com/r/spaceflight/comments/6ueula/yes_it_really_has_taken_nasa_11_years_to_develop/dls6qsi/ (https://www.reddit.com/r/spaceflight/comments/6ueula/yes_it_really_has_taken_nasa_11_years_to_develop/dls6qsi/)

Can anyone verify this? (Pardon me if this was already known if it is true).

So I pulled up some higher resolution pictures, and I've changed my mind. Orion and Dragon's parachutes are visibly different. They may be based on the same design (they are quite similar), but they definitely can't be the exact same model. Note particularly the vents on the sides and the round gap at the top of Orion's parachutes.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: woods170 on 08/18/2017 10:06 pm
Quote
I have it on good authority (the goodest) that the Orion parachutes are identical to the Dragon parachutes. Indistinguishable. Both spacecraft are using the same model and vendor.

https://www.reddit.com/r/spaceflight/comments/6ueula/yes_it_really_has_taken_nasa_11_years_to_develop/dls6qsi/ (https://www.reddit.com/r/spaceflight/comments/6ueula/yes_it_really_has_taken_nasa_11_years_to_develop/dls6qsi/)

Can anyone verify this? (Pardon me if this was already known if it is true).
The Reddit post is partially incorrect. The vendor is the same for Dragon and Orion. The parachutes however are different critters.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: tvg98 on 08/18/2017 11:36 pm
Quote
I have it on good authority (the goodest) that the Orion parachutes are identical to the Dragon parachutes. Indistinguishable. Both spacecraft are using the same model and vendor.

https://www.reddit.com/r/spaceflight/comments/6ueula/yes_it_really_has_taken_nasa_11_years_to_develop/dls6qsi/ (https://www.reddit.com/r/spaceflight/comments/6ueula/yes_it_really_has_taken_nasa_11_years_to_develop/dls6qsi/)

Can anyone verify this? (Pardon me if this was already known if it is true).
The Reddit post is partially incorrect. The vendor is the same for Dragon and Orion. The parachutes however are different critters.

Thanks to whitelancer64 and woods170 for clearing it up.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: FutureSpaceTourist on 08/20/2017 01:17 am
Quote
Pics of SpaceX spacesuit developed for NASA commercial crew program coming out next week. Undergoing ocean landing mobility/safety tests.

https://twitter.com/elonmusk/status/899075756508065793
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: DatUser14 on 08/25/2017 08:00 pm
Crew Dragon shaped tarp spotted in hawthorne by u/wishiwasonmaul, no real idea what it is. https://www.reddit.com/r/SpaceXLounge/comments/6w0kdy/dragon_about_to_leave_the_nest/
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: the_other_Doug on 08/29/2017 11:33 pm
Admittedly, I have not been following this issue closely.  But it occurs to me that the Super Draco pods have to remain on Dragon V2 to provide for an LAS capability, correct?

Therefore, the only thing that would need to be re-engineered onto this vehicle, should SpaceX decide to pursue propulsive landings in the future with Dragon V2, would be some form of landing legs, right?

I mean, it's not like the Super Draco pods are being removed from the vehicle... right?
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Kansan52 on 08/30/2017 12:28 am
Admittedly, I have not been following this issue closely.  But it occurs to me that the Super Draco pods have to remain on Dragon V2 to provide for an LAS capability, correct?

Therefore, the only thing that would need to be re-engineered onto this vehicle, should SpaceX decide to pursue propulsive landings in the future with Dragon V2, would be some form of landing legs, right?

I mean, it's not like the Super Draco pods are being removed from the vehicle... right?

From what little we know, yes, all the work for propulsive landing remains, just too much work with too little reward. The landing legs won't be included to save weight would be my guess.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Jcc on 08/30/2017 12:30 am
It seems to me that he is talking about the possibility of flying a Dragon 2 cargo mission in between DM-2 and PCM-1X (SpaceX's 1st post certification mission; non-official mission notation).

FWIW, my take is that he was referring to flying Dragon 2 cargo under the original CRS contract, prior to the beginning of the next CRS, and that would benefit Dragon 2 flight rate, which is a plus for crew safety.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: guckyfan on 08/30/2017 07:02 am
It seems to me that he is talking about the possibility of flying a Dragon 2 cargo mission in between DM-2 and PCM-1X (SpaceX's 1st post certification mission; non-official mission notation).

FWIW, my take is that he was referring to flying Dragon 2 cargo under the original CRS contract, prior to the beginning of the next CRS, and that would benefit Dragon 2 flight rate, which is a plus for crew safety.

You think SpaceX would fly Dragon 2 at CRS 1 prices? CRS 2 prices are higher. I also think the payload capacity is higher. Flying a mix of Dragon 1 and Dragon 2 for cargo will also increase cost.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Semmel on 08/30/2017 09:22 am
Admittedly, I have not been following this issue closely.  But it occurs to me that the Super Draco pods have to remain on Dragon V2 to provide for an LAS capability, correct?

Therefore, the only thing that would need to be re-engineered onto this vehicle, should SpaceX decide to pursue propulsive landings in the future with Dragon V2, would be some form of landing legs, right?

I mean, it's not like the Super Draco pods are being removed from the vehicle... right?

Its not just the landing legs. As stated many times before, its the qualification process that is expensive, not the engineering and thats the most likely reason for cancellation. So, as you say, if SpaceX decide to use powered landings, it needs to perform the qualification tests which are likely much more expensive than any hardware that needs to be added.

On the vehicle side, its more than the legs as well. Its avionics, control software (BIG part here, more expensive then the legs most likely). Also, on descend, in order to target the landing spot accurately enough they need active guidance and control. Without GPS because the reentry plasma will block the GPS signal. So they will need some other method to determine their position. Dont know how that is going to work but doesnt seem easy. Then there is the active descend control. This can be done with changing the center of gravity of the capsule. So that would need an active sled or bladder tanks with a pump.

All this would have to be qualified additional to the current D2 capabilities. Please dont think of the difference between water landing D2 by parachute and powered landing D2 by Superdracos as "just the legs".
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: the_other_Doug on 08/30/2017 05:35 pm
Admittedly, I have not been following this issue closely.  But it occurs to me that the Super Draco pods have to remain on Dragon V2 to provide for an LAS capability, correct?

Therefore, the only thing that would need to be re-engineered onto this vehicle, should SpaceX decide to pursue propulsive landings in the future with Dragon V2, would be some form of landing legs, right?

I mean, it's not like the Super Draco pods are being removed from the vehicle... right?

Its not just the landing legs. As stated many times before, its the qualification process that is expensive, not the engineering and thats the most likely reason for cancellation. So, as you say, if SpaceX decide to use powered landings, it needs to perform the qualification tests which are likely much more expensive than any hardware that needs to be added.

On the vehicle side, its more than the legs as well. Its avionics, control software (BIG part here, more expensive then the legs most likely). Also, on descend, in order to target the landing spot accurately enough they need active guidance and control. Without GPS because the reentry plasma will block the GPS signal. So they will need some other method to determine their position. Dont know how that is going to work but doesnt seem easy. Then there is the active descend control. This can be done with changing the center of gravity of the capsule. So that would need an active sled or bladder tanks with a pump.

All this would have to be qualified additional to the current D2 capabilities. Please dont think of the difference between water landing D2 by parachute and powered landing D2 by Superdracos as "just the legs".

Oh, I get all that.  I'm very clear that it's not just "Hey, add some legs and we're good to go."

I was just confirming my understanding that, from a hardware point of view only, nothing has been done to the Crew Dragon, per this decision, that completely rules out development of propulsive landings later on, if (and only if) SpaceX decides it makes sense to invest the money into its qualification.

I'm not discussing the odds of SpaceX actually deciding to do so in the future, trust me... ;)
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: deruch on 08/30/2017 11:14 pm
Admittedly, I have not been following this issue closely.  But it occurs to me that the Super Draco pods have to remain on Dragon V2 to provide for an LAS capability, correct?

Therefore, the only thing that would need to be re-engineered onto this vehicle, should SpaceX decide to pursue propulsive landings in the future with Dragon V2, would be some form of landing legs, right?

I mean, it's not like the Super Draco pods are being removed from the vehicle... right?

Its not just the landing legs. As stated many times before, its the qualification process that is expensive, not the engineering and thats the most likely reason for cancellation. So, as you say, if SpaceX decide to use powered landings, it needs to perform the qualification tests which are likely much more expensive than any hardware that needs to be added.

On the vehicle side, its more than the legs as well. Its avionics, control software (BIG part here, more expensive then the legs most likely). Also, on descend, in order to target the landing spot accurately enough they need active guidance and control. Without GPS because the reentry plasma will block the GPS signal. So they will need some other method to determine their position. Dont know how that is going to work but doesnt seem easy. Then there is the active descend control. This can be done with changing the center of gravity of the capsule. So that would need an active sled or bladder tanks with a pump.

All this would have to be qualified additional to the current D2 capabilities. Please dont think of the difference between water landing D2 by parachute and powered landing D2 by Superdracos as "just the legs".

Oh, I get all that.  I'm very clear that it's not just "Hey, add some legs and we're good to go."

I was just confirming my understanding that, from a hardware point of view only, nothing has been done to the Crew Dragon, per this decision, that completely rules out development of propulsive landings later on, if (and only if) SpaceX decides it makes sense to invest the money into its qualification.

I'm not discussing the odds of SpaceX actually deciding to do so in the future, trust me... ;)
[speculation] If the SuperDracos are only going to need the "gross" control necessary for launch abort and not the "fine" control needed for propulsive landing then they may make hardware changes to simplify the system or to lower costs.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: cppetrie on 08/30/2017 11:20 pm
Admittedly, I have not been following this issue closely.  But it occurs to me that the Super Draco pods have to remain on Dragon V2 to provide for an LAS capability, correct?

Therefore, the only thing that would need to be re-engineered onto this vehicle, should SpaceX decide to pursue propulsive landings in the future with Dragon V2, would be some form of landing legs, right?

I mean, it's not like the Super Draco pods are being removed from the vehicle... right?

Its not just the landing legs. As stated many times before, its the qualification process that is expensive, not the engineering and thats the most likely reason for cancellation. So, as you say, if SpaceX decide to use powered landings, it needs to perform the qualification tests which are likely much more expensive than any hardware that needs to be added.

On the vehicle side, its more than the legs as well. Its avionics, control software (BIG part here, more expensive then the legs most likely). Also, on descend, in order to target the landing spot accurately enough they need active guidance and control. Without GPS because the reentry plasma will block the GPS signal. So they will need some other method to determine their position. Dont know how that is going to work but doesnt seem easy. Then there is the active descend control. This can be done with changing the center of gravity of the capsule. So that would need an active sled or bladder tanks with a pump.

All this would have to be qualified additional to the current D2 capabilities. Please dont think of the difference between water landing D2 by parachute and powered landing D2 by Superdracos as "just the legs".

Oh, I get all that.  I'm very clear that it's not just "Hey, add some legs and we're good to go."

I was just confirming my understanding that, from a hardware point of view only, nothing has been done to the Crew Dragon, per this decision, that completely rules out development of propulsive landings later on, if (and only if) SpaceX decides it makes sense to invest the money into its qualification.

I'm not discussing the odds of SpaceX actually deciding to do so in the future, trust me... ;)
[speculation] If the SuperDracos are only going to need the "gross" control necessary for launch abort and not the "fine" control needed for propulsive landing then they may make hardware changes to simplify the system or to lower costs.
Wouldn't that require requalifying them? At this point it is likely cheaper and easier to keep them as is, even if their is some cost savings from a simpler design.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Jcc on 08/30/2017 11:32 pm
It seems to me that he is talking about the possibility of flying a Dragon 2 cargo mission in between DM-2 and PCM-1X (SpaceX's 1st post certification mission; non-official mission notation).

FWIW, my take is that he was referring to flying Dragon 2 cargo under the original CRS contract, prior to the beginning of the next CRS, and that would benefit Dragon 2 flight rate, which is a plus for crew safety.

You think SpaceX would fly Dragon 2 at CRS 1 prices? CRS 2 prices are higher. I also think the payload capacity is higher. Flying a mix of Dragon 1 and Dragon 2 for cargo will also increase cost.

From what I gather, pricing is negotiated per mission, because there are always variable costs due to special payload needs. They are already flying reused Dragon 1s, and there may be an equitable adjustment of pricing downward if that saves SpaceX money (it didn't save much on CRS-11, but the prospect is that it will in the future), likewise if they use reflown boosters. If NASA requests Dragon 2 for a mission and are willing pay for it I'm sure SpaceX will oblige them. NASA can do that as long as the maximum cap for the CRS contract is not exceeded by the end of 20 flights.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: IntoTheVoid on 08/31/2017 01:19 am
It seems to me that he is talking about the possibility of flying a Dragon 2 cargo mission in between DM-2 and PCM-1X (SpaceX's 1st post certification mission; non-official mission notation).

FWIW, my take is that he was referring to flying Dragon 2 cargo under the original CRS contract, prior to the beginning of the next CRS, and that would benefit Dragon 2 flight rate, which is a plus for crew safety.

You think SpaceX would fly Dragon 2 at CRS 1 prices? CRS 2 prices are higher. I also think the payload capacity is higher. Flying a mix of Dragon 1 and Dragon 2 for cargo will also increase cost.

From what I gather, pricing is negotiated per mission, because there are always variable costs due to special payload needs. They are already flying reused Dragon 1s, and there may be an equitable adjustment of pricing downward if that saves SpaceX money (it didn't save much on CRS-11, but the prospect is that it will in the future), likewise if they use reflown boosters. If NASA requests Dragon 2 for a mission and are willing pay for it I'm sure SpaceX will oblige them. NASA can do that as long as the maximum cap for the CRS contract is not exceeded by the end of 20 flights.

Why is (seemingly) everyone so hung up on flying Dragon 2 under CRS1? The CRS2 contract is awarded. If NASA wants a Dragon 2 cargo mission, they'll fly it under CRS2 even if all the missions for CRS1 haven't been flown out yet. It probably doesn't even require any contract mods; worst case is that they need to extend the CRS1 POP to get the final mission in.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: woods170 on 08/31/2017 05:55 am
If NASA requests Dragon 2 for a mission and are willing pay for it I'm sure SpaceX will oblige them. NASA can do that as long as the maximum cap for the CRS contract is not exceeded by the end of 20 flights.

Why is (seemingly) everyone so hung up on flying Dragon 2 under CRS1? The CRS2 contract is awarded. If NASA wants a Dragon 2 cargo mission, they'll fly it under CRS2 even if all the missions for CRS1 haven't been flown out yet. It probably doesn't even require any contract mods; worst case is that they need to extend the CRS1 POP to get the final mission in.
There will be no flights under CRS-1 using Dragon 2.
Dragon 2 is for CRS-2 only.
People suggesting otherwise are living in fantasy-land.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: guckyfan on 08/31/2017 06:33 am
Dragon 2 is for CRS-2 only.
People suggesting otherwise are living in fantasy-land.

That would be NASA, it seeems. Suggesting that SpaceX fly cargo Dragon 2. Cargo Dragon 1 will fly until the end of 2019 at least. Meaning cargo Dragon 2 will fly in 2020. Now NASA suggesting that cargo Dragon 2 should fly ahead of crew Dragon would put Commercial Crew flights in late 2020.

Suggesting SpaceX fly a mix of CRS 1 and CRS 2? That would need financial compensation beyond the existing contracts as it would drive cost.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: woods170 on 08/31/2017 07:08 am
Dragon 2 is for CRS-2 only.
People suggesting otherwise are living in fantasy-land.

That would be NASA, it seeems. Suggesting that SpaceX fly cargo Dragon 2. Cargo Dragon 1 will fly until the end of 2019 at least. Meaning cargo Dragon 2 will fly in 2020. Now NASA suggesting that cargo Dragon 2 should fly ahead of crew Dragon would put Commercial Crew flights in late 2020.
Emphasis mine.
It won't happen because such a wish is outside the scope of the CCP contracts. NASA would have to pay for the delays and reshuffling of the flight manifest outside the current scope of CCtCAP. Not to mention that NASA would have a helluva time explaining why this new "requirement" is not equally applied to the other CCP provider (Boeing).
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Roy_H on 08/31/2017 08:32 am
Unless you guys know something I don't all this talk about NASA requesting a D2 cargo mission before regular crew flights is mis-represented. I believe they said that this may happen, which means it is probably a decision made by SpaceX and not a requirement by NASA. CRS contracts for cargo delivery to ISS are for tons of supplies delivered and prices are not negotiated on a per flight basis. I.E. SpaceX was not paid for the LOM (NASA  paid for lost cargo only). Only restriction for D2 cargo missions is that no large items requiring the larger berthing hatch be included. If SpaceX chooses to use D2 for cargo before crew rotations, they will not, in my opinion, have any extra financial compensation from NASA.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: hamerad on 08/31/2017 09:07 am
Could this talk of cargo before crew just be cargo going up on one of the demo missions? Or would the risk of loss be too great for this to be considered?
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: FutureSpaceTourist on 09/02/2017 01:38 am
Quote
First Look at the Crew Access Arm For Launch Complex 39A
Posted on September 1, 2017 at 8:18 am by Amanda Griffin.

Astronauts Bob Behnken and Eric Boe walk down the Crew Access Arm being built by SpaceX for Launch Complex 39A at NASA’s Kennedy Space Center in Florida. The access arm will be installed on the launch pad, providing a bridge between the crew access tower and SpaceX’s Crew Dragon – or Dragon 2 – spacecraft for astronauts flying to the International Space Station on the company’s Falcon 9 rocket as part of NASA’s Commercial Crew Program.

The access arm is being readied for installation in early 2018. It will be installed 70 feet higher than the former space shuttle access arm on the launch pad’s Fixed Service Structure. SpaceX continues to modify the historic launch site from its former space shuttle days, removing more than 500,000 pounds of steel from the pad structure, including the Rotating Service Structure that was once used for accessing the payload bay of the shuttle. SpaceX also is using the modernized site to launch commercial payloads, as well as cargo resupply missions to and from the International Space Station for NASA. The first SpaceX launch from the historic Apollo and space shuttle site was this past February.

NASA’s Commercial Crew Program is working with private companies, Boeing and SpaceX, with a goal of once again flying people to and from the International Space Station, launching from the United States. Boeing is building the CST-100 Starliner to launch on an United Launch Alliance Atlas V rocket from Space Launch Complex 41. For information on Boeing and ULA’s work on Space Launch Complex 41, visit: https://www.nasa.gov/feature/crew-access-arm-installed-for-starliner-missions.

This entry was posted in NASA on September 1, 2017 by Amanda Griffin.

https://blogs.nasa.gov/commercialcrew/2017/09/01/first-look-at-the-crew-access-arm-for-launch-complex-39a/

Caption for photo:
Quote
Astronauts Bob Behnken and Eric Boe walk down the Crew Access Arm being built by SpaceX for Launch Complex 39A at NASA’s Kennedy Space Center in Florida.
Photo Credit: SpaceX

Picture was previously posted here (http://forum.nasaspaceflight.com/index.php?topic=41015.msg1709163#msg1709163) but higher res attached.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: woods170 on 09/02/2017 05:50 pm
Note: installation of the CAA is now no longer planned for this year, but for "early in 2018". Previously, it was assumed it would be installed during the stand-down of LC-39A for FH conversion. Now it looks like it will not be installed during that particular stand-down.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: ScottMC on 09/08/2017 09:27 pm
New Instagram picture of Crew Dragon.  Shame that guy's standing in the way ;)

https://www.instagram.com/p/BYyvO2WA3Ra/

Questions I have:
 1) Where was that photo taken?  The roof looks kind of lower than expected.
 2) Is that a real Crew Dragon or a mock-up?  It looks a bit different, but it might just be a new angle.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: IanThePineapple on 09/08/2017 09:31 pm
New Instagram picture of Crew Dragon.  Shame that guy's standing in the way ;)

https://www.instagram.com/p/BYyvO2WA3Ra/

Questions I have:
 1) Where was that photo taken?  The roof looks kind of lower than expected.
 2) Is that a real Crew Dragon or a mock-up?  It looks a bit different, but it might just be a new angle.

1. The SpaceX Hawthorne facility, with core 1042 and an unknown core in the background.
2. I don't know, it would make sense for it to be real
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Herb Schaltegger on 09/08/2017 09:51 pm
New Instagram picture of Crew Dragon.  Shame that guy's standing in the way ;)

https://www.instagram.com/p/BYyvO2WA3Ra/

Questions I have:
 1) Where was that photo taken?  The roof looks kind of lower than expected.
 2) Is that a real Crew Dragon or a mock-up?  It looks a bit different, but it might just be a new angle.

1. The SpaceX Hawthorne facility, with core 1042 and an unknown core in the background.
2. I don't know, it would make sense for it to be real

That outer mold line looks WAAAY too smooth and un-featured for it to be real.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Lars-J on 09/08/2017 09:52 pm
Yes, that is a mock-up for sure.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: old_sellsword on 09/08/2017 09:59 pm
New Instagram picture of Crew Dragon.  Shame that guy's standing in the way ;)

https://www.instagram.com/p/BYyvO2WA3Ra/

Questions I have:
 1) Where was that photo taken?  The roof looks kind of lower than expected.
 2) Is that a real Crew Dragon or a mock-up?  It looks a bit different, but it might just be a new angle.

1) Inside their headquarters, right inside "tankland." SpaceX usually edits all the pictures that come out of their factory to make it look a lot more white and sterile than it really is.

2) Looks to me like the Dragon Reveal mockup they were hauling around campus (https://www.reddit.com/r/spacex/comments/6w0p5n/dragon_being_dropped_off_at_hawthorne_today/) a few weeks ago.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: wannamoonbase on 09/08/2017 10:10 pm
Yes, that is a mock-up for sure.

Where are the connections for life support?

Looks cool, lets see how it works.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: x15_fan on 10/06/2017 03:26 am
Is there any update on the D2 ECLSS testing at JSC? I looked through the thread and couldn’t find anything.


Sent from my iPhone using Tapatalk
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Craig_VG on 10/06/2017 06:56 pm
NASA has updated CC launch dates:


Quote
Targeted Test Flight Dates:
Boeing Orbital Flight Test (uncrewed): August 2018
Boeing Crew Flight Test (crewed): November 2018
SpaceX Demonstration Mission 1 (uncrewed): April 2018
SpaceX Demonstration Mission 2 (crewed): August 2018


https://blogs.nasa.gov/commercialcrew/2017/10/05/nasas-commercial-crew-program-target-test-flight-dates/
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Geron on 10/18/2017 04:42 am
Dragon 2 splashdown tests completed!!
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: woods170 on 10/18/2017 08:20 am
Dragon 2 splashdown tests completed!!
I'll point out that the image in your post is of the mock-up used for crew recovery training.
See here: https://blogs.nasa.gov/commercialcrew/2017/07/20/recovery-and-rescue-teams-practice-with-full-size-crew-dragon-trainer/
It has absolutely nothing to do with splashdown tests.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: woods170 on 10/18/2017 08:30 am
From the video here: https://forum.nasaspaceflight.com/index.php?topic=44009.0

Crew Dragon hardware coming together!
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Andy Bandy on 10/20/2017 01:44 am
Is there any update on the D2 ECLSS testing at JSC? I looked through the thread and couldn’t find anything.


Sent from my iPhone using Tapatalk

Has anyone heard how the ECLSS development is going?
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: deruch on 10/20/2017 04:53 am
Is there any update on the D2 ECLSS testing at JSC? I looked through the thread and couldn’t find anything.

Has anyone heard how the ECLSS development is going?

The attached slide from the NAC HEO meetings in March 2017 shows that SpaceX completed their ECLSS Integrated Testing in November 2016.

The last announcement regarding the ECLSS work was also from March:

https://www.nasa.gov/feature/eclss-put-to-the-test-for-commercial-crew-missions
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: woods170 on 10/20/2017 07:53 am
Additionally, from here:https://forum.nasaspaceflight.com/index.php?topic=37802.msg1739807#msg1739807

- The July update shows that in June 2017 all ECLSS work had been completed.
- The July update shows that first pressurized tests with crew wearing spacesuits had been completed.

Requirement for this latter test was that ECLSS work had finished. The fact that the pressurized test with crew wearing spacesuits has been performed is a clear additional indicator that ECLSS work for Crew Dragon has been completed.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: woods170 on 10/27/2017 06:18 am
Moving this to the appropriate thread:

If SpaceX is ahead of ULA for its equivalent flight, why hasn't it released comparable images of its progress?
Why do you feel compelled to bring up SpaceX in a ULA thread?
I didn't.  I was responding to someone else who did.

 - Ed Kyle
Excellent.

That said: You may have noticed that ever since SpaceX switched from Falcon 9 v1.0 to v1.1, and went into the hardware-phase for Crew Dragon, they have been steadily decreasing the amount of publically released images of NEW stuff (such as Falcon 9 Block 5 and Crew Dragon).
For example: The first decent image (albeit small) of the integrated crew module of the DM-1 Crew Dragon was found in a presentation from the recent ISPCS. (https://forum.nasaspaceflight.com/index.php?topic=41016.msg1738939#msg1738939)
Another example: images of NASA astronauts inspecting the DM-1 Crew Dragon at Hawthorne (as posted on the NASA Commercial Crew blog) were deliberately framed to show as little of the spacecraft as possible. (https://blogs.nasa.gov/commercialcrew/2017/04/11/astronauts-work-with-crew-dragon-qualification-vehicle/)
Third example: the first image of the SpaceX CAA for 39A reveals basically nothing about how it looks from the outside. (https://blogs.nasa.gov/commercialcrew/2017/09/01/first-look-at-the-crew-access-arm-for-launch-complex-39a/)

I have it straight from folks at SpaceX that this is being done deliberately.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Johnnyhinbos on 10/27/2017 06:30 am
That begs the question, “to what end?” What is the reasoning for this paucity of images?

Surely if you’ve been told it’s deliberate then you must have been told why...
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: woods170 on 10/27/2017 06:46 am
That begs the question, “to what end?” What is the reasoning for this paucity of images?

Surely if you’ve been told it’s deliberate then you must have been told why...

No, they haven't told me and I didn't bother to ask. Experience has tought them (and me) to not always ask why Elon et al. do the things the way they do.
Remember that from initial looks things like first stage recovery & reuse, capsule-integrated LAS, nine-engine first stages and other examples, didn't make sense. Until they did.
I expect a reason for the current low-profile attitude, regarding Crew Dragon and F9 Block 5, to become clear over time.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: vaporcobra on 10/27/2017 06:53 am
That begs the question, “to what end?” What is the reasoning for this paucity of images?

Surely if you’ve been told it’s deliberate then you must have been told why...

No, they haven't told me and I didn't bother to ask. Experience has thought them (and me) to not always ask why Elon et al. do the things the way they do.
Remember that from initial looks things like first stage recovery & reuse, capsule-integrated LAS, nine-engine first stages and other examples, didn't make sense. Until they did.
I expect a reason for the current low-profile attitude, regarding Crew Dragon and F9 Block 5, to become clear over time.

The spaceflight fanatic inside me yearns for a high res version of ANY of the pictures in those slides, but you are certainly correct. I'm sure the wait will be worthwhile, and I'd rather have SpaceX be focused on development/preparation over photography if it comes down to it :D Thanks for sharing what you know!
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: sghill on 10/27/2017 12:23 pm
That begs the question, “to what end?” What is the reasoning for this paucity of images?

Surely if you’ve been told it’s deliberate then you must have been told why...

1) Information is no one's business but their own, except as required by contracts.
2) Elon doesn't believe in the patent system because the IP gets ripped off the moment it becomes public. Every day IP is not public is one less day a competitor has to gain on SpaceX (and no, I'm not thinking of ULA here).
3) Information "fuzziness" gives them room to make changes, improvements, or solve problems without the associated expectation resetting that causes negative headlines.

Tesla does all the same stuff.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: acsawdey on 10/27/2017 03:59 pm
2) Elon doesn't believe in the patent system because the IP gets ripped off the moment it becomes public. Every day IP is not public is one less day a competitor has to gain on SpaceX (and no, I'm not thinking of ULA here).

Trade secret law is a powerful way to protect stuff, especially if you can keep anybody from taking a close look at it. Hard to prevent somebody from buying a car and taking apart, but you can't just go and buy a Dragon 2 off the lot. Restricting photos keeps the secret sauce secret, is required to be able to claim trade secret status, and also keeps the aforementioned not-ULA parties from figuring it out.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: AncientU on 10/27/2017 04:35 pm
2) Elon doesn't believe in the patent system because the IP gets ripped off the moment it becomes public. Every day IP is not public is one less day a competitor has to gain on SpaceX (and no, I'm not thinking of ULA here).

Trade secret law is a powerful way to protect stuff, especially if you can keep anybody from taking a close look at it. Hard to prevent somebody from buying a car and taking apart, but you can't just go and buy a Dragon 2 off the lot. Restricting photos keeps the secret sauce secret, is required to be able to claim trade secret status, and also keeps the aforementioned not-ULA parties from figuring it out.

Copy/borrow SpaceX IP?

http://forum.nasaspaceflight.com/index.php?topic=43780.msg1725136#msg1725136
China

http://forum.nasaspaceflight.com/index.php?topic=41330.msg1741246#msg1741246
Europe
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: AbuSimbel on 10/27/2017 04:49 pm
Are we really discussing this? We have official NASA timelines and development updates about the CCP, plenty of insights from people in the industry to judge the progress of both providers yet we toss them aside and ask '...but where are the pictures?'. I mean if the number of pictures released was indicative of actual progress with a space program SLS would be launching to Mars by now.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Lars-J on 10/27/2017 07:05 pm
Are we really discussing this? We have official NASA timelines and development updates about the CCP, plenty of insights from people in the industry to judge the progress of both providers yet we toss them aside and ask '...but where are the pictures?'. I mean if the number of pictures released was indicative of actual progress with a space program SLS would be launching to Mars by now.

Exactly. And we all know that they (NASA and SLS contractors) for example make a huuuge production whenever an engine is tested, so that should give us a clue that the quantity of press images does not correlate to progress. (Can you imagine if SpaceX made a big bru-haha about every engine test, let alone every Raptor test?)  ;D
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: AncientU on 10/27/2017 09:18 pm
Are we really discussing this? We have official NASA timelines and development updates about the CCP, plenty of insights from people in the industry to judge the progress of both providers yet we toss them aside and ask '...but where are the pictures?'. I mean if the number of pictures released was indicative of actual progress with a space program SLS would be launching to Mars by now.

Exactly. And we all know that they (NASA and SLS contractors) for example make a huuuge production whenever an engine is tested, so that should give us a clue that the quantity of press images does not correlate to progress. (Can you imagine if SpaceX made a big bru-haha about every engine test, let alone every Raptor test?)  ;D

You mean the daily engine tests?  ...multiple times daily frequently?
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: rpapo on 10/27/2017 09:45 pm
You mean the daily engine tests?  ...multiple times daily frequently?
I seem to recall that a few years back (2011 or so?) when ULA ran an advertisement which claimed that "some rocket companies" were all talk and little action, replacing the rocket in the image with a microphone.  The implied competitor being SpaceX.  Times have changed.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: ClayJar on 10/27/2017 10:36 pm
You mean the daily engine tests?  ...multiple times daily frequently?
I seem to recall that a few years back (2011 or so?) when ULA ran an advertisement which claimed that "some rocket companies" were all talk and little action, replacing the rocket in the image with a microphone.  The implied competitor being SpaceX.  Times have changed.

Was that ULA or Pratt & Whitney Rocketdyne ?  I can't find the ad, but the earliest references I could find here appeared to indicate the latter.  (I remember the ad well, but it's hard to find since Google can't quite read images out of your head just yet.)

Edit: Found it.  PWR in January 2012.  An article about it: Link (http://www.parabolicarc.com/2012/01/22/pratt-whitney-rocketdyne-takes-shot-at-spacex/).  Small image of the ad attached.

Just to make it so perhaps it'll be easier to find a reference later, this is the ad about SpaceX and Pratt & Whitney Rocketdyne (PWR) with a microphone and the text "Others' idea of making noise."  (The text at the bottom of the advertisement reads, "While the other guys launch powerful press conferences, we power launches of people and critical payloads. In fact, we’ve powered 14 launches in 12 months with 100% success. While the other guys deliver press conferences, we deliver astronauts and important communication, science and national defense payloads. So, before you listen to their next promise, scan the tag and watch all 14 zero-fail launches. At FutureSpaceUSA.com.")  It is not from United Launch Alliance (ULA) or specifically mentioning Atlas V or Delta IV.  (There, now it should be easier to Google later, I hope. ;))
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: S.Paulissen on 10/27/2017 10:47 pm
You mean the daily engine tests?  ...multiple times daily frequently?
I seem to recall that a few years back (2011 or so?) when ULA ran an advertisement which claimed that "some rocket companies" were all talk and little action, replacing the rocket in the image with a microphone.  The implied competitor being SpaceX.  Times have changed.

Was that ULA or Pratt & Whitney Rocketdyne ?  I can't find the ad, but the earliest references I could find here appeared to indicate the latter.  (I remember the ad well, but it's hard to find since Google can't quite read images out of your head just yet.)

Edit: Found it.  PWR in January 2012.  An article about it: Link (http://www.parabolicarc.com/2012/01/22/pratt-whitney-rocketdyne-takes-shot-at-spacex/).  Small image of the ad attached.
https://youtu.be/wynOKjPTmZU

Oddly enough, Bing to the rescue. Google failed me. :|
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: rpapo on 10/27/2017 11:05 pm
You mean the daily engine tests?  ...multiple times daily frequently?
I seem to recall that a few years back (2011 or so?) when ULA ran an advertisement which claimed that "some rocket companies" were all talk and little action, replacing the rocket in the image with a microphone.  The implied competitor being SpaceX.  Times have changed.
Was that ULA or Pratt & Whitney Rocketdyne ? 
That's the one.  I mis-remembered who ran the ad.  And that explains why I couldn't find it with Google either.  I kept looking for ULA...
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: meekGee on 10/28/2017 03:31 am
You mean the daily engine tests?  ...multiple times daily frequently?
I seem to recall that a few years back (2011 or so?) when ULA ran an advertisement which claimed that "some rocket companies" were all talk and little action, replacing the rocket in the image with a microphone.  The implied competitor being SpaceX.  Times have changed.

Maybe they should have put the money into tech development instead of advertising.

Irony (n) - This exact scenario.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: octavo on 10/28/2017 04:51 am
You mean the daily engine tests?  ...multiple times daily frequently?
I seem to recall that a few years back (2011 or so?) when ULA ran an advertisement which claimed that "some rocket companies" were all talk and little action, replacing the rocket in the image with a microphone.  The implied competitor being SpaceX.  Times have changed.

Was that ULA or Pratt & Whitney Rocketdyne ?  I can't find the ad, but the earliest references I could find here appeared to indicate the latter.  (I remember the ad well, but it's hard to find since Google can't quite read images out of your head just yet.)

Edit: Found it.  PWR in January 2012.  An article about it: Link (http://www.parabolicarc.com/2012/01/22/pratt-whitney-rocketdyne-takes-shot-at-spacex/).  Small image of the ad attached.
https://www.youtube.com/watch?v=wynOKjPTmZU

Oddly enough, Bing to the rescue. Google failed me. :|
Thanks for posting - I hadn't seen this campaign before. Pretty aggressive, but from a marketing perspective, this was probably the right pitch at the time. Of course, in hindsight it looks petty and hilariously short sighted.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: deruch on 10/28/2017 06:57 am
That begs the question, “to what end?” What is the reasoning for this paucity of images?

Surely if you’ve been told it’s deliberate then you must have been told why...

My assumption is that it's mainly to conserve "reveal impact" for when the mission eventually gets to the pad.  Plus what sghill mentioned about being able to make changes without having to reset expectations. 
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: IntoTheVoid on 10/28/2017 03:31 pm
You mean the daily engine tests?  ...multiple times daily frequently?
I seem to recall that a few years back (2011 or so?) when ULA ran an advertisement which claimed that "some rocket companies" were all talk and little action, replacing the rocket in the image with a microphone.  The implied competitor being SpaceX.  Times have changed.

Maybe they should have put the money into tech development instead of advertising.

Irony (n) - This exact scenario.

I also find the "we deliver astronauts" line amusing, given that they haven't delivered any astronauts since before before that ad and SpaceX seems to be the next to do so U.S.-wise.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: meekGee on 10/28/2017 04:45 pm
You mean the daily engine tests?  ...multiple times daily frequently?
I seem to recall that a few years back (2011 or so?) when ULA ran an advertisement which claimed that "some rocket companies" were all talk and little action, replacing the rocket in the image with a microphone.  The implied competitor being SpaceX.  Times have changed.

Was that ULA or Pratt & Whitney Rocketdyne ?  I can't find the ad, but the earliest references I could find here appeared to indicate the latter.  (I remember the ad well, but it's hard to find since Google can't quite read images out of your head just yet.)

Edit: Found it.  PWR in January 2012.  An article about it: Link (http://www.parabolicarc.com/2012/01/22/pratt-whitney-rocketdyne-takes-shot-at-spacex/).  Small image of the ad attached.
https://www.youtube.com/watch?v=wynOKjPTmZU

Oddly enough, Bing to the rescue. Google failed me. :|
Thanks for posting - I hadn't seen this campaign before. Pretty aggressive, but from a marketing perspective, this was probably the right pitch at the time. Of course, in hindsight it looks petty and hilariously short sighted.
From a marketing perspective, sure.

But this is not a marketing company.

From a corporate governance perspective, the emphasis on ridicule and denial was pathetic even at the time and continues in some ways even today. (Mostly the denial part)
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: clongton on 10/28/2017 04:53 pm
I love video of launches and enjoyed this one. PWR is rightly proud of what it has accomplished but they put all that pride into the toilet when they used it to ridicule SpaceX. I agree - pathetic is the right word.
First they ignore you - then they laugh at you - then they fight you - then you win.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: midnightrider3000 on 10/28/2017 05:09 pm
"During that same period, SpaceX has unveiled two new projects: the heavy-lift Falcon Heavy, which is scheduled to arrive at the Vandenberg launch site by the end of 2012; "


WHOOPS, looks like the driver of the Falcon Havy got lost on the way to Vandenberg and wound up at the Cape. Also, Why do people have the impression that Elon isn't very good at meeting schedules?
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: AbuSimbel on 10/28/2017 05:22 pm
The driver is also veering a bit Off-topic, isn't he?
Let's keep it on Dragon 2... Speaking of which: if i remember correctly NASA announced that the downselection of the test pilots for the inaugural crewed missions of D2 and CST-100 would take place during the summer... Any reasons for the delay? When should we expect an official release by NASA?
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: gongora on 10/28/2017 05:26 pm
The driver is also veering a bit Off-topic, isn't he?
Let's keep it on Dragon 2... Speaking of which: if i remember correctly NASA announced that the downselection of the test pilots for the inaugural crewed missions of D2 and CST-100 would take place during the summer... Any reasons for the delay? When should we expect an official release by NASA?

I think last we heard it should be announced by end of year.

Any further posts on the PWR ad will be deleted.  Back on topic please.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: octavo on 11/02/2017 10:29 am
Could you fit Dragon v2 + trunk inside a standard f9 fairing?

I searched the thread, but I couldn't find anything...
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: MATTBLAK on 11/02/2017 10:34 am
If you are referring to the 5.2 meter fairing - then it should. And I too have wondered what has happened to the crew and/or tentative test launch date. Anyone know what's going on about that?
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: guckyfan on 11/02/2017 11:50 am
Could you fit Dragon v2 + trunk inside a standard f9 fairing?

I searched the thread, but I couldn't find anything...

Fit is not the problem. It was argued that it needs a new payload adapter from the ground up which is a major development.
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: spacenut on 11/02/2017 11:56 am
Why would they need to fit Dragon 2 inside a fairing?
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: rpapo on 11/02/2017 12:12 pm
Why would they need to fit Dragon 2 inside a fairing?
It was somebody's notion of killing two birds with one stone: Use the FH Demo mission to test the fairing, and yet still use it to lob a Dragon 2 on a trip around the moon.

We have way too many Rube Goldbergs around this place...
Title: Re: SpaceX Dragon 2 Updates and Discussion - Thread 2
Post by: Robotbeat on 11/02/2017 12:20 pm
Could you fit Dragon v2 + trunk inside a standard f9 fairing?

I searched the thread, but I couldn