NASASpaceFlight.com Forum
SpaceX Vehicles and Missions => SpaceX Early Days Archive Section => Topic started by: Chris Bergin on 11/17/2012 02:07 am
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Thread 7 for general discussion on SpaceX and their vehicles.
Previous threads (now over 1.5 milllion views for the five SpaceX threads alone):
Thread 1:
http://forum.nasaspaceflight.com/index.php?topic=19228.0
Thread 2:
http://forum.nasaspaceflight.com/index.php?topic=22769.0
Thread 3:
http://forum.nasaspaceflight.com/index.php?topic=24179.0
Thread 4:
http://forum.nasaspaceflight.com/index.php?topic=25597.0
Thread 5:
http://forum.nasaspaceflight.com/index.php?topic=28006.0
Thread 6:
http://forum.nasaspaceflight.com/index.php?topic=29476.0
SpaceX news articles on this site:
Old: http://forum.nasaspaceflight.com/index.php?topic=21862.0 (links)
Then recent news articles, not linked above, as we moved to a tag group system:
All recent: http://www.nasaspaceflight.com/tag/spacex/
L2 SpaceX - now a large section:
http://forum.nasaspaceflight.com/index.php?action=tags&tags=SpaceX
NOTE:
These are very busy threads. Remember, this site is 99+ percent read by people not logged in to post. When you post, lots and lots of people get to read it. So, make it a worthwhile post, be civil and remember this is a community.
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The Dragon appears to have had a few radiation issues on the last flight and from what I can tell from reading here it happened on one other occasion. That seems a bit high even for commercial non rad hardened electronics. Perhaps they were just unlucky, but there may be a bigger problem there.
The radiation environment in LEO is comparatively benign when you compare it to deep space or even the surface of Mars. Any trip beyond LEO means traveling through the Van Allen Radiation belts and the radiation exposure there is hundreds of times greater than in LEO.
This tells me that a rad hardened computer must be in the plans as I just don't see the current setup working for anything but LEO.
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The Dragon isn't heading beyond LEO in the near future. Time enough to solve the Van Allen radiation problem in a few years time.
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Curiosity showed that a dragon on mars should do just as well as a dragon in Leo as the radiation environments are cOmparable.
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So recently there was mention of a talk given by a SpaceX GNC Engineer. Where are the notes/video from this talk?
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http://www.youtube.com/watch?v=ilaUQxIlB_I
Looks too short to be even F9 v1.0 first stage tankage.
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Looks too short to be even F9 v1.0 first stage tankage.
Maybe a GSE side tank. I didn't see "SpaceX" anywhere on that vehicle, did you?
PS. In nearby Moody, TX, corner of Farm-to-Market 107 and State Hwy 317.
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The Dragon isn't heading beyond LEO in the near future. Time enough to solve the Van Allen radiation problem in a few years time.
I agree with this. However, it seems like they might want to start on this right away. With the current situation a significant solar event might be problematic even in LEO.
Curiosity showed that a dragon on mars should do just as well as a dragon in Leo as the radiation environments are cOmparable.
So far everything I've seen from the radiation experiment on Curiosity are in arbitrary units. The raw counts look to be about half on the surface as they counted during cruise. Since the detector was inside shielded by other spacecraft structures during cruise the ratio between the Mars surface and deep space must be somewhat more.
During the latest Curiosity teleconference there was some updates from the radiation experiment. When asked about the arbitrary units vs actual units like rems or rads, it was stated that the absolute numbers should be available sometime in December.
It seems to me that the numbers for the surface of Mars will come in a bit higher than LEO. Even if the numbers are more of less equivalent, the huge differences in exposure time make Mars mission radiation exposure at least two orders of magnitude larger.
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Looks too short to be even F9 v1.0 first stage tankage.
Maybe a GSE side tank. I didn't see "SpaceX" anywhere on that vehicle, did you?
The diameter to me looks about right for an F9 stage, something I wouldn't expect for a GSE tank. It's covered in tarp or something, why should there be visible SpaceX markings?
Hmm, this video shows a similar/same thing and one comments says it's a wind turbine tower core.
http://www.youtube.com/watch?v=Ux0pf8yEg_4
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Could be a foundation form for a windmill, a grain storage silo, or other things besides rocket tanks.
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Very likely to be a 12 ft diameter tank, but too short to be a F9 tank, nor Grasshopper.
http://i.imgur.com/iOUkb.jpg
http://i.imgur.com/UDp9n.jpg
http://i.imgur.com/kf29F.jpg
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Very likely to be a 12 ft diameter tank, but too short to be a F9 tank, nor Grasshopper.
http://i.imgur.com/iOUkb.jpg
http://i.imgur.com/UDp9n.jpg
http://i.imgur.com/kf29F.jpg
I was going to post a similar setup and conclusion. Even the 1.1 LOX tank is longer (happens to be only a foot difference from the 1.0 LOX/RP-1 tank combo, 78' vs 77')
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I think I remember the F9 first stage is carried on a special trailer designed to support the structure while in transit. The one i the video looks like a regular one.
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Hi, everyone.
This is my first post on the forum, and I have a question.
Does anyone know, how much costs dragon capsule?
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Hi, everyone.
This is my first post on the forum, and I have a question.
Does anyone know, how much costs dragon capsule?
That is not public information. However, since SpaceX sells cargo delivery services to NASA at $133M per flight, and they advertise $54M for the Falcon 9, it must cost them less than $79M if they're profiting.
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Isn't profit included in the F9 pricing?
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We don't know cost but we do know advertised price, and I believe Elon's been quoted saying the Dragon costs about the same as a F9.
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However, since SpaceX sells cargo delivery services to NASA at $133M per flight, and they advertise $54M for the Falcon 9, it must cost them less than $79M if they're profiting.
Combine this with the previous post and you get that Dragon costs at most $54M. However, the $25M left includes "extra services"; the actual amount of profit in there is anyone's guess.
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However, since SpaceX sells cargo delivery services to NASA at $133M per flight, and they advertise $54M for the Falcon 9, it must cost them less than $79M if they're profiting.
Combine this with the previous post and you get that Dragon costs at most $54M. However, the $25M left includes "extra services"; the actual amount of profit in there is anyone's guess.
That price ( $133M ) is averaged over all the flights. The first flight will cost less than the last flight of that contract do to inflation. Plus I believe that contract also included start up cost ( I read that some place ).
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Posted on SpX-2 General Discussion:
http://www.aviationweek.com/Blogs.aspx?plckBlogId=Blog:04ce340e-4b63-4d23-9695-d49ab661f385&plckPostId=Blog%3A04ce340e-4b63-4d23-9695-d49ab661f385Post%3Aa8b87703-93f9-4cdf-885f-9429605e14df
Dragon uses the same design principles as the Shuttle and Hubble.
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Interview with elon musk done by BBC soon before/after the RAeS talk:
BBC News: SpaceX CEO Elon Musk: 'Europe's rocket has no chance' (http://www.bbc.co.uk/news/science-environment-20389148)
Most of the standard talking points he usually uses. Mentions some fighting words to Arianespace, as quoted in the news article title. Says that Falcon v1.1 is cheaper than Falcon v1.0. Unclear whether this is in absolute cost or $/m3. 10-15 years to humans on Mars, quality increases with production amounts (in regards to Falcon and Merlin), etc
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Well, considering SpaceX moved the Merlin-1D turbo pumps in house, that in and of itself should result in a measurable cost savings.
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Elon Musk: With Jobs Gone, Google Will Win mobile (And Look Out For The Hyperloop)
http://techcrunch.com/2012/11/19/elon-musk-with-jobs-gone-google-will-win-mobile-and-look-out-for-the-hyperloop/
Various titbits about SpaceX here, nothing really new.
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Elon's piss off list:
Banking industry - check.
Rocket industry - check.
Car industry - check.
yawn.
hmmm... aha - Airplane manufacturers and Airliners - ooo yeah!
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Very likely to be a 12 ft diameter tank, but too short to be a F9 tank, nor Grasshopper.
http://i.imgur.com/iOUkb.jpg
http://i.imgur.com/UDp9n.jpg
http://i.imgur.com/kf29F.jpg
I get a kick out of the energy shown in these threads. Hope the next SpaceX type company gets some of these high energy people.
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SpaceX CEO Elon Musk: 'Europe's rocket has no chance'
http://www.bbc.co.uk/news/science-environment-20382025
Big advertising! Great show. He only thing he has to do is deliver!
He has to be that chaep. He has to lift a full dragon to orbit. The absolute new 1.1 must perform and be reliable........
I think he will do a good job, but he will suffer from all people making the big advertising. He advertises vor 200% and we will get 100%. This will make life for Ariane 5 and 6 difficult, but no chance is a litlle much.
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If a customer pays in full for a Falcon 9 launch how long does it take SpaceX to get the F9 to the launch pad and ready for launch?
Are they or have they planned on keeping and F9 v1.1's on hand to be ready for a customer to launch sooner?
( I was reading somewere about Delta II being kept ready within 30 days to launch for DoD ).
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( I was reading somewere about Delta II being kept ready within 30 days to launch for DoD ).
It was 60 days and only for GPS. The long pole is not launch vehicle build but integration.
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If a customer pays in full for a Falcon 9 launch how long does it take SpaceX to get the F9 to the launch pad and ready for launch?
Are they or have they planned on keeping and F9 v1.1's on hand to be ready for a customer to launch sooner?
( I was reading somewere about Delta II being kept ready within 30 days to launch for DoD ).
NLS II contract usually is L-30 month. If I remember correctly, the CRS is 21 months, with a premium for less time with 12months left as "to negotiate". But Dragon is already fully integrated to the Falcon 9. The 2009 User Guide states no less than 18 months prior to launch for authority to proceed. But again, that's very tight for payload integration and verification. And I'm pretty sure they've learned a lot about operations since then.
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Got to hand it to Elon Musk, here's the newest Falcon 9 design.... 9v1.2?
Saw this on the Tesla Motors Facebook page.....
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Got to hand it to Elon Musk, here's the newest Falcon 9 design.... 9v1.2?
Saw this on the Tesla Motors Facebook page.....
You are off topic ;)
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https://twitter.com/elonmusk/status/272518429368541184
New short video, nothing really new.
http://forum.nasaspaceflight.com/index.php?topic=30190.msg983550#msg983550
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Odd that the video is posted to some random account.
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Odd that the video is posted to some random account.
Here is the same video from the spacexchannel: https://www.youtube.com/watch?v=V-zG5QvlBaw
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Odd that the video is posted to some random account.
I think its the account of a SpaceX employee or their PR people. Via google I've found they have other private videos on the account (non viewable).
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So regarding Dragons....
This is actually very obvious, and has been bugging me for a while.
SpaceX are very early to put up engineering development hardware on display (F1, F9, Dragon).
Also, once they started talking publicly about powered recovery of F9S1, Grasshopper was up in no time, and is now even flying.
They have Dragon, and they've been testing SuperDracos for quite some time now.
... so where's Dragon 2? There was a mockup on display, but nothing more.
I think all of this got reconciled when Elon said - "We didn't really know what we were doing with Dragon 1" and "Dragon 2 will look really cool", etc.
I think once Elon decides on a change in direction, he doesn't waste time on sunk-cost projects just because they're half-way through the engineering pipeline.
My tea-leaf reading from this is that the possibility that Dragon 2 has been greatly revised away from Dragon 1 + SuperDracos, and the conspicuously missing Dragon/Draco test-bed hopping around McGregor are in agreement here.
EDIT: Copied into Dragon thread
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So regarding Dragons....
This is actually very obvious, and has been bugging me for a while.
SpaceX are very early to put up engineering development hardware on display (F1, F9, Dragon).
Also, once they started talking publicly about powered recovery of F9S1, Grasshopper was up in no time, and is now even flying.
They have Dragon, and they've been testing SuperDracos for quite some time now.
... so where's Dragon 2? There was a mockup on display, but nothing more.
I think all of this got reconciled when Elon said - "We didn't really know what we were doing with Dragon 1" and "Dragon 2 will look really cool", etc.
I think once Elon decides on a change in direction, he doesn't waste time on sunk-cost projects just because they're half-way through the engineering pipeline.
My tea-leaf reading from this is that the possibility that Dragon 2 has been greatly revised away from Dragon 1 + SuperDracos, and the conspicuously missing Dragon/Draco test-bed hopping around McGregor are in agreement here.
I appreciate your reasoning and I too stumble over that contradiction between Dragon 2 is the manned Dragon for ISS-access and it is completely different to the present cargo Dragon.
But SpaceX has the CCiCap contract to meet and is in competition with Boeing on this. Do you really see they can have a completely new Dragon ready in time?
And convince NASA to accept this complete turnaround?
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I can't tell for sure, but IMO SpaceX is more likely to go with "direct-to-new-design"
A regular contractor would basically be thinking "I've already invested in this design, I need to book revenue on it" - the usual over-applied cliches - "the enemy of good is better", "walk before you run", etc.
SpaceX is thinking "Since we now know better, proceeding further with this design becomes a diversion - the more we invest in it, the bigger the detour from the path we now want to take" and so they chalk off the current design as a learning experience and move on as fast as possible.
They're also thinking "We've got a head start - a good way to spend it is to allow a major iteration where the competition can't afford it."
Mind reader, I have become! Accurate? we'll see.
I can tell you that till a few days ago, I was sure they'll do an upgraded Dragon (as shown in the video/mockup - very similar to the current one, but with SDs) But with Elon, you often can't tell whether he's talking about the hardware that's about to fly, or the hardware that he's currently envisioning for a few years down the road.
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Dragon 2? Dragonrider? Crew Dragon? IMO they're probably all the same thing.
The crew trials from earlier this year suggest that the "new" Dragon will not have a drastically different mold-line, at least, not on the inside. If, as Elon says, the SuperDracos are much larger than previously depicted, and closer together on the "sides", it may well have a distinctly different exterior apperance. Imagine 4 large pods bulging from either side. Other major features that could change its apperance are the deployable landing legs, if they moved to the exterior rather than through the heat shield, and forward facing windscreens, if they are deemed nessessary.
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A regular contractor ... "the enemy of good is better",
SpaceX is thinking "Since we now know better, proceeding further with this design becomes a diversion - the more we invest in it, the bigger the detour from the path we now want to take" and so they chalk off the current design as a learning experience and move on as fast as possible.
This is most especially true in the context of Mars colonization as their central goal.
The why/how/what hierarchy arises again. In my opinion, the why (Mars) is far more decisive and potent a reason to switch paths midstream than competitive concerns like below:
They're also thinking "We've got a head start - a good way to spend it is to allow a major iteration where the competition can't afford it."
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SpaceX has the CCiCap contract to meet and is in competition with Boeing on this. Do you really see they can have a completely new Dragon ready in time?
They've certainly been thinking about capsules for a while now. They may already have a paper design that they like. If so, it may come together fairly quick.
And convince NASA to accept this complete turnaround?
NASA seemed unbothered by a change in rocket from V1.0 to V1.1. Version 1.1 is in many ways a new rocket. It even uses different engines. Is that reasonable precedent?
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So regarding Dragons....
This is actually very obvious, and has been bugging me for a while.
SpaceX are very early to put up engineering development hardware on display (F1, F9, Dragon).
Also, once they started talking publicly about powered recovery of F9S1, Grasshopper was up in no time, and is now even flying.
They have Dragon, and they've been testing SuperDracos for quite some time now.
... so where's Dragon 2? There was a mockup on display, but nothing more.
I think all of this got reconciled when Elon said - "We didn't really know what we were doing with Dragon 1" and "Dragon 2 will look really cool", etc.
I think once Elon decides on a change in direction, he doesn't waste time on sunk-cost projects just because they're half-way through the engineering pipeline.
My tea-leaf reading from this is that the possibility that Dragon 2 has been greatly revised away from Dragon 1 + SuperDracos, and the conspicuously missing Dragon/Draco test-bed hopping around McGregor are in agreement here.
I appreciate your reasoning and I too stumble over that contradiction between Dragon 2 is the manned Dragon for ISS-access and it is completely different to the present cargo Dragon.
But SpaceX has the CCiCap contract to meet and is in competition with Boeing on this. Do you really see they can have a completely new Dragon ready in time?
And convince NASA to accept this complete turnaround?
SpaceX probably competed for CCiCap with this new Dragon, so NASA has already shown their approval for the changes.
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SpaceX probably competed for CCiCap with this new Dragon, so NASA has already shown their approval for the changes.
Heh, in that case, all we need to look for is that badly obfuscated PDF or PPT that's sure to be lurking somewhere in the NASA public archives
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Hi, everyone.
This is my first post on the forum, and I have a question.
Does anyone know, how much costs dragon capsule?
That is not public information. However, since SpaceX sells cargo delivery services to NASA at $133M per flight, and they advertise $54M for the Falcon 9, it must cost them less than $79M if they're profiting.
I was told by their head GNC engineer that they will do a flight of a refurbished/used dragon (rocket and all) for about $80 million.
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The Dragon appears to have had a few radiation issues on the last flight and from what I can tell from reading here it happened on one other occasion. That seems a bit high even for commercial non rad hardened electronics. Perhaps they were just unlucky, but there may be a bigger problem there.
The radiation environment in LEO is comparatively benign when you compare it to deep space or even the surface of Mars. Any trip beyond LEO means traveling through the Van Allen Radiation belts and the radiation exposure there is hundreds of times greater than in LEO.
This tells me that a rad hardened computer must be in the plans as I just don't see the current setup working for anything but LEO.
1) They experienced less radiation problems with their electronics than they expected (or designed for), so they consider themselves lucky, and their design to be quite robust to radiation.
2) They know they will have to go rad-hard for Mars.
Its funny to keep seeing people bringing this up:
Its kind of like the whole engine out discussion. SpaceX built a system with multiple redundant components (9 rocket engines/ 3 computers with 2 independent cores each (with voting)) From day one the system was designed to be able to be robust to a problem or failure of one of those components (engine pressure release/ rad hit causing a reboot), and then the system flew and performed exactly as expected when the planed for even occurred.
That is all that happened, but boy do people like to throw up heaps of concerns and warnings and calls for changes.
They will learn everything useful from these events and use the knowledge going forward, but they are optimizing for cost, not perfection.
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Hi, everyone.
This is my first post on the forum, and I have a question.
Does anyone know, how much costs dragon capsule?
That is not public information. However, since SpaceX sells cargo delivery services to NASA at $133M per flight, and they advertise $54M for the Falcon 9, it must cost them less than $79M if they're profiting.
I was told by their head GNC engineer that they will do a flight of a refurbished/used dragon (rocket and all) for about $80 million.
80-54=26
$26M for a Dragon capsule sounds about right compared to some private jets. That would be in today's dollars. The difference between $80M and $133M is the start up costs and inflation. $80M is most likely the base price and added cost would be added for the specific mission per flight.
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I found that article quite interesting. I wish there were similar articles for every F9 and Dragon component made by outside manufacturers.
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I found that article quite interesting. I wish there were similar articles for every F9 and Dragon component made by outside manufacturers.
There are actually a bunch of these I've seen. They show up on google news with little fanfare. Two more (and there are more if I could find them again):
http://www.plm.automation.siemens.com/en_us/about_us/success/case_study.cfm?Component=30328&ComponentTemplate=1481
http://www.altium.com/successes/testimonials/aerospace/en/spacex.cfm
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Robust Servo Motors Survive Launch Conditions to Optimize Rocket Fuel Burn
http://www.micromo.com/application-case-study-space-x-shuttle-launch.aspx
Some quotes from the article I found particularly interesting:
The first stage features nine engines that burn for approximately three minutes, and the second stage includes one engine that burns for approximately seven minutes. Because of the duration of the burn for each stages, the control loops can actually run relatively slowly. “The whole valve doesn't necessarily need to be fast,” says [Juerg Frefel, Avionics Engineer at SpaceX]. “It's a closed-loop system, which means that the command to the valve is to go to a certain angle. The outer loop adjusts the angle of the valve and the inner loop keeps the position steady in case it gets pushed around [by shock/vibration].”
Rocket engines produce heat as well as vibration, but contrary to what a person might think, thermal management does not pose a significant challenge in this application.
Much of the heat is radiated and is reflected away. In addition, given the relatively brief duration of the stages, the unit’s thermal mass makes it resistant to rapid temperature swings. “The actuator still has three to four pounds of mass, which means that in three minutes it doesn't heat up that dramatically,” Frefel says.
To control cost and production timelines, the SpaceX philosophy is to try to work with stock components whenever possible. Nothing special was done to the MICROMO motors to ruggedize them for the application; the design team simply ordered standard products.
From the Siemens (http://www.plm.automation.siemens.com/en_us/about_us/success/case_study.cfm?Component=30328&ComponentTemplate=1481) link:
SpaceX has modeled the entire Falcon 1 and Falcon 9 rockets and the Dragon capsule in NX. The software has no trouble handling more than 25,000-part assemblies. “Having the ability to work with an assembly of such size in a timely manner is very important,” says Thompson. “The entire assembly takes only five to 10 minutes to load.” Once loaded, a virtual mockup of the rocket enables designers to readily find interferences. A major benefit in working with large assemblies is “designing in context,” which allows various component parts to be developed and completed all while working in the assembly. Designing in context means immediate feedback relative to fit and feasibility. Conversely, without the ability to load all the relevant components around the area of concern, designing the components to fit precisely is a much more difficult and time-consuming task. In addition to NX’s assembly strengths, SpaceX designers use NX to simulate motion, such as the separation between the first and second stages, to further check their work.
SpaceX leverages its NX data in other ways as well. Technicians on the shop floor look at NX models as they build the rocket to better understand a rocket’s inner workings. This is particularly helpful for seeing the routes of tubes and wires within the rocket, for instance.
From the Altium (http://www.altium.com/successes/testimonials/aerospace/en/spacex.cfm) link:
To ensure its launch vehicles always perform at this extraordinary level, SpaceX develops many of its boards and controllers under the fault–tolerant discipline. This time consuming engineering technique ensures that all systems can continue to operate despite a given component failing. Controllers and PCBs are fitted with additional components and back-up mechanisms for greater reliability.
Altium’s live design capabilities mean that the simplest modifications are automatically adjusted in all previous board and schematic work. The result: a flexible but reliable development and documentation process for SpaceX’s catalogue of PCB designs. Altium’s comprehensive libraries were found to be one of the biggest development boons for SpaceX. The library feature provided engineers with the latest and most up-to-date components in a user-friendly system. Engineers were also able to add new components, which allowed for greater customization and board enhancements.
Since introducing Altium Designer into its development process, SpaceX has enjoyed considerable improvements in its productivity. Without prior knowledge of the software, engineers were easily able to complete designs without the usual rigorous training required from separate or loosely integrated tools. Within just two weeks of applying Altium technology, engineers were able to create a power distribution and regulation board. This trend has continued. SpaceX has found its project turn over has increased exponentially.
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I know I'm banging my head against a brick wall here, but it doesn't take five of you to complain on the thread about someone being rude. You do one thing and one thing only, you hit REPORT TO MODERATOR - it's right there, on every post.
By posting "OMG!" you only create two problem posts. Reporting it allows us to remove the one problem post.
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http://www.wacotrib.com/blogs/staff/joescience/About-last-nights-SpaceX-test.html
SpaceX conducted two single engine tests last night, of the Merlin 1D engine and the Merlin vacuum engine. The tests were three minutes apart, just before 10PM.
They probably do these tests daily, but what I found interesting is these two separate tests only minutes apart.
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They probably do these tests daily, but what I found interesting is these two separate tests only minutes apart.
Well, unless there are technical or practical reasons not to do so, I suppose sticking tests close together to reduce the noise nuisance is being a good neighbour.
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Posting here where it is less "off topic"
From http://shitelonsays.com/transcript/elon-musk-lecture-at-the-royal-aeronautical-society-2012-11-16
Just the url of this website had me laughing to the point where a passing coworker wondered what was so funny. I love it.
In a world obsessed with carefully scripted talking points Elon "walks the walk and talks the talk". You don't have to agree with all or anything he says, or believe a word of it, but I think you have to admire the guy.
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That is a great site! :D
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In a world obsessed with carefully scripted talking points Elon "walks the walk and talks the talk". You don't have to agree with all or anything he says, or believe a word of it, but I think you have to admire the guy.
I think that Musk is a horrible speaker, but one can see that he is talking without a script and that makes him appear much more genuine, believable and likeable.
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That's a curious definition of "horrible". Unconventional maybe?
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Well, he studders a lot and has lots of uhhm and hmms in it, when he speaks that is what I mean. Lets say that "people would generally characterize him as a bad speaker", but I think it makes him appear more genuine and credible than someone who clearly practiced every word in front of a mirror.
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That's a curious definition of "horrible". Unconventional maybe?
Unconventional suggests he's good at it but not in the traditional manner. I think it's more the case that he's just not that good.
Mitigated by the fact that he's extremely smart and well informed, and doing interesting stuff.
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This might have been covered elsewhere (couldn't find it) but I remember, a few years ago, people were talking excitedly about Kwajalein Atoll as a wonderful place for SpaceX to launch from, what with it being only 8 degrees north.
I know they launched the Falcon 1 from there but suddenly, even with a bursting order book, there's no mention of the Atoll even with the benefits of launching from that close to the equator.
Any thoughts?
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This might have been covered elsewhere (couldn't find it) but I remember, a few years ago, people were talking excitedly about Kwajalein Atoll as a wonderful place for SpaceX to launch from, what with it being only 8 degrees north.
I know they launched the Falcon 1 from there but suddenly, even with a bursting order book, there's no mention of the Atoll even with the benefits of launching from that close to the equator.
Any thoughts?
It turns out, logistics sucks for an island in the middle of the ocean far away from civilization. Also, Falcon 1 is barely worth it and the island would be too crowded to launch a Falcon 9 from, realistically. Lots more reasons, too.
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What does how Elon speaks got to do with Falcon and Dragon? Trim time.
Don't answer that, I'm being rhetorical ;)
Back on track with something more interesting please.
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Here are a few supplier webpages relating to SpaceX.
CAD Package - NX http://www.plm.automation.siemens.com/en_us/about_us/success/case_study.cfm?Component=30328&ComponentTemplate=1481 (http://www.plm.automation.siemens.com/en_us/about_us/success/case_study.cfm?Component=30328&ComponentTemplate=1481)
Board Layout - Altium http://www.altium.com/successes/testimonials/aerospace/en/spacex.cfm (http://www.altium.com/successes/testimonials/aerospace/en/spacex.cfm)
INS - Honeywell SIGI (stated publicly multiple places)
http://www51.honeywell.com/aero/common/documents/myaerospacecatalog-documents/Space-documents/Space_Integrated_GPS-INS.pdf (http://www51.honeywell.com/aero/common/documents/myaerospacecatalog-documents/Space-documents/Space_Integrated_GPS-INS.pdf)
Valves - Precision Fluid Controls (look closely and you will see at least two of these valves in pictures of Merlins)
http://precisionfluidcontrols.com/valves-pressure-controls-aerospace-industry/home.php (http://precisionfluidcontrols.com/valves-pressure-controls-aerospace-industry/home.php)
TVC Actuator - Jasc
http://jasc-controls.com/jasc-industry-listing/space/space-actuators/thrust-vector-control-actuator-part-101424-5/ (http://jasc-controls.com/jasc-industry-listing/space/space-actuators/thrust-vector-control-actuator-part-101424-5/)
MVAC Bi-Propellant Valve - JASC
http://jasc-controls.com/jasc-industry-listing/space/space-fluid-management/bi-propellant-valve/
Flowmeters for testing - Hoffer
http://www.hofferflow.com/news-featured-spacex.asp (http://www.hofferflow.com/news-featured-spacex.asp)
Valves - Marotta
http://www.marotta.com/files/Datasheets/mv74_ds.pdf (http://www.marotta.com/files/Datasheets/mv74_ds.pdf)
Turbopump - Barber Nichols
http://www.barber-nichols.com/products/rocket-engine-turbopumps (http://www.barber-nichols.com/products/rocket-engine-turbopumps)
Dragon Solar Array Steering Motors & GNC Bay door motors - Maxon
http://www.maxonmotorusa.com/maxon/view/news/MEDIENMITTEILUNG-SpaceX (http://www.maxonmotorusa.com/maxon/view/news/MEDIENMITTEILUNG-SpaceX)
Composite Software - Siemens Fibersim
http://www.plm.automation.siemens.com/CaseStudyWeb/dispatch/viewResource.html?resourceId=29661 (http://www.plm.automation.siemens.com/CaseStudyWeb/dispatch/viewResource.html?resourceId=29661)
Merlin Fuel Trim Valve Motor - Micromo
http://www.micromo.com/application-case-study-space-x-shuttle-launch.aspx (http://www.micromo.com/application-case-study-space-x-shuttle-launch.aspx)
Dragon Parachutes - Airborne Systems
http://www.airborne-sys.com/pages/view/spacex-dragon-capsule (http://www.airborne-sys.com/pages/view/spacex-dragon-capsule)
Dragon Eye prox ops sensor - ASC
http://www.advancedscientificconcepts.com/products/dragoneye.html (http://www.advancedscientificconcepts.com/products/dragoneye.html)
Non-Explosive Actuators for trunk release etc - Cooper Interconnect
http://www.connectorsupplier.com/in-cooper-spacex-specifier-071912 (http://www.connectorsupplier.com/in-cooper-spacex-specifier-071912)
http://www.cooperindustries.com/content/public/en/wiring_devices/interconnect/products/Mil-Aero_Products/non-explosive_actuators.html (http://www.cooperindustries.com/content/public/en/wiring_devices/interconnect/products/Mil-Aero_Products/non-explosive_actuators.html)
Flight Terminaton System - Ensign Bickford
http://www.spacex.com/F9-001.php (http://www.spacex.com/F9-001.php)
http://www.eba-d.com/ (http://www.eba-d.com/)
Prototype Spacesuit Mockups - Orbital Outfitters
http://orbitaloutfitters.com/2012/05/21/suit-mock-ups-for-spacex-nasa-crew-trials/ (http://orbitaloutfitters.com/2012/05/21/suit-mock-ups-for-spacex-nasa-crew-trials/)
AS9100 Quality Management System Consulting - Oxebridge
http://www.oxebridge.com/emma/?p=934 (http://www.oxebridge.com/emma/?p=934)
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Thanks for great list !
One interesting detail:
Airborne Systems says that they do supply parachutes not only for the Dragon, but for first stages as well:
http://www.airborne-sys.com/pages/view/spacex-falcon-1-and-falcon-9
"Airborne Systems has developed the recovery systems for all of the SpaceX launch vehicles.
This includes the 1st stage of both Falcon 1 and Falcon 9. Both systems use a mortar deployed
drogue stage followed by a main parachute stage. Falcon 1 lands under a single 75 ft slotted
polyconical parachute. Falcon 9 lands under four 116 ft ringsail parachutes."
From the size and number of parachutes used for F9-S1, it looks like they are intended for post-flight inspection, not for stage re-use.
If this is true, and CRS1 first stage was equipped with chutes, then SpaceX do have a contract with some boat company for recovery. May be it's possible to find this boat company website ?
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One interesting detail:
Airborne Systems says that they do supply parachutes not only for the Dragon, but for first stages as well:
http://www.airborne-sys.com/pages/view/spacex-falcon-1-and-falcon-9
As I understand it, these were used on the first two F9 flights, but stage reentry failed and subsequent flight first stages were not fitted with 'chutes.
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This might have been covered elsewhere (couldn't find it) but I remember, a few years ago, people were talking excitedly about Kwajalein Atoll as a wonderful place for SpaceX to launch from, what with it being only 8 degrees north.
I know they launched the Falcon 1 from there but suddenly, even with a bursting order book, there's no mention of the Atoll even with the benefits of launching from that close to the equator.
F1 was a rather small rocket and comparably easy to transport to Kwajalein. Falcon9 and its payloads are much bigger, making the effort more expensive and complicated.
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Wonder if the maritime asserts for a NASA commercial crew flight would be based on a LSD from the US Navy? You get the vertol aircrafts & water crafts attached to the LSD with extensive medical facilities. There is also the option of flying the crew back to shore in a V22.
Also won't be that costly, if you could integrate the recovery operation as part of the LSD's training schedule.
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Wonder if the maritime asserts for a NASA commercial crew flight would be based on a LSD from the US Navy? You get the vertol aircrafts & water crafts attached to the LSD with extensive medical facilities. There is also the option of flying the crew back to shore in a V22.
Also won't be that costly, if you could integrate the recovery operation as part of the LSD's training schedule.
You do realize that at typical LSD has a crew of 400+ There are smaller (cheaper) ships available.
Of course, since the USS Wasp is not up to combat par an has been used as a PR piece prowling US ports for the better part of a decade now, we might have a better option ;)
(link on the Wasp, http://www.defensenews.com/article/20120630/DEFREG02/306300003/Wasp-Mystery-Solved-Deployments-Skipped-Due-Outdated-Combat-System )
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The falcon 9 is really impressive and elon musk say the first stage and second stage will be fully reusable,but I got a question that what material the landing legs use for impact attenuation,is the Aluminum honeycomb just like the apollo or penumatic piston or any else?
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The falcon 9 is really impressive and elon musk say the first stage and second stage will be fully reusable,but I got a question that what material the landing legs use for impact attenuation,is the Aluminum honeycomb just like the apollo or penumatic piston or any else?
Grasshopper has pneumatic shock absorbers. F9r will likely be the same, but unconfirmed. The loading on the legs will be much greater than was seen on the LM.
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errrr.... First stage does not reach space
I am pretty sure it does reach space (IIRC separation is at or close to 100km), but not orbit...
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But pneumatic shock absorbers have not been used in recent years,you mean the oil-pneumatic shock absorber?And I doubt this shock absorber can endure the bad condition in the outer space.
errrr.... First stage does not reach space...
okay....but the second stage does,so what shock absober the second stage use?......
First off, welcome to the forums.
Re-usable 2nd stage doesn't exist and isn't even being tested yet and it won't be for something like 5 years. This is too early to be talking about, no one has much clue on to how the second stage will land, most likely even SpaceX.
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In other news, looks like its confirmed that SpaceX isn't going to be doing stratolaunch.
http://www.space.com/18747-stratolaunch-orbital-sciences-replaces-spacex.html
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In other news, looks like its confirmed that SpaceX isn't going to be doing stratolaunch.
http://www.space.com/18747-stratolaunch-orbital-sciences-replaces-spacex.html
thank you again.Is this forum official?
Official what?
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SpaceX Bests Orbital Sciences In First OSP-3 Duels
Space Exploration Technologies (SpaceX) has won the first two U.S. Air Force contracts aimed at fostering competition in the U.S. launch market over a new design proposed by Orbital Sciences.
SpaceX will use its Falcon 9 v1.1 to boost NASA’s Deep Space Climate Observatory (DSCOVR) in November 2014 and the Falcon 9 Heavy for launch of a Space Test Program satellite in September 2015, says Lt. Gen. Ellen Pawlikowski, program executive officer for Air Force space programs.
http://www.aviationweek.com/Article.aspx?id=/article-xml/awx_12_05_2012_p0-524585.xml&p=1
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That's an official Falcon Heavy on the USAF manifest? What sort of STP satellite would need one and chance a new rocket? I could see it for a really high delta-v mission. But I understand that USAF doesn't have any need beyond GSO.
Again, not that USAF doesn't have such payloads. Just that such a payload, for a test program, would be hugely expensive.
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That's an official Falcon Heavy on the USAF manifest?
Dunno. So far AwWeek seems to be the only one reporting this, I'd wait for more sources before calling it "official". It does cite official quotes, so it's reasonable that it'll hold up.
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That's an official Falcon Heavy on the USAF manifest? What sort of STP satellite would need one and chance a new rocket? I could see it for a really high delta-v mission. But I understand that USAF doesn't have any need beyond GSO.
Again, not that USAF doesn't have such payloads. Just that such a payload, for a test program, would be hugely expensive.
Well, perhaps USAF sees it as a relatively modest investment in a new heavy-lift capability so they don't have to buy so many of the expensive Delta IV Heavies.
Probably not going to use all of Falcon Heavy's lift capability, and probably isn't the most expensive USAF payload.
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GoreSat is back, sigh... Good risk reduction Falcon 9 flight.
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GoreSat is back, sigh... Good risk reduction Falcon 9 flight.
That's an L1 mission. Will they use a kick stage? The Falcon 9 US has never done anything beyond LEO. How's the flight profile to an L1 launch? I guess similar to an L2 launch, a TLI or a C3=0. But I'm guessing if that's a short mission (2hr) or a long mission (8hs) and if it would require multiple restarts.
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GoreSat is back, sigh... Good risk reduction Falcon 9 flight.
That's an L1 mission. Will they use a kick stage?
Already discussed here: http://forum.nasaspaceflight.com/index.php?topic=16053.msg490780#msg490780
DSCOVR has a not-to-exceed launch mass of 750 kg. F9v1.1 is projected to do 3500 kg to C3=0 so there should be ample margin.
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GoreSat is back, sigh... Good risk reduction Falcon 9 flight.
That's an L1 mission. Will they use a kick stage? The Falcon 9 US has never done anything beyond LEO. How's the flight profile to an L1 launch? I guess similar to an L2 launch, a TLI or a C3=0. But I'm guessing if that's a short mission (2hr) or a long mission (8hs) and if it would require multiple restarts.
Not strictly correct. On the second flight of Falcon 9, they did a restart of the second stage to go into a highly elliptical orbit, outside LEO. I suppose the burn itself was LEO, but the stage most certainly wasn't just in LEO. Even for an escape mission, your burn is usually in LEO.
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Description of DSCOVR payload: https://www.fbo.gov/utils/view?id=168229cf3e11961a9b8324a5dc8f80d3
Description of STP-2 payload: https://www.fbo.gov/utils/view?id=36de6af7670d2636c8c195173dd500e1
Good stuff.
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Falcon Heavy mission profile for STP-2 would be:
The LSC shall plan and execute a mission that includes the insertion orbits detailed below. The LSC shall also demonstrate a minimum of three upper stage burns and carry 5,000 kg (TBR) of LSC-provided ballast for the entire mission.
Insertion Orbit #1
Deliver the IPS to a circular orbit with an orbital altitude of 720 km and an orbital inclination of 24º. Deploy only the COSMIC-2 payload set, up to six APLs (TBR), and actuate up to eight P-PODs (TBR).
Insertion Orbit #2
Deliver the IPS (with remaining payloads) to the elliptical orbit with a perigee of 6,000 km, apogee of 12,000 km, and an orbital inclination of 45º. Deploy the DSX payload followed by remaining APLs and actuate remaining P-PODs. After deployment of these payloads, the LV shall enter a coast phase of [3 hours threshold, 5 hours objective]. After the coast phase, the LV shall execute an upper stage restart with a minimum duration of 5 seconds (TBR).
The maximum expected mass of COSMIC-2 including propellant is 1450 kg (3197 lbs). This mass includes all six SVs, their support structure and their separation systems.
This, with 5,000 kg of ballast mentioned above and DSX payload that could be up to 640 kg comes up to 7 tonnes total liftoff mass (there are a minimum of two and up to 6 APLs each 180 kg, but I neglected them here)? Also, an odd choice of insertion orbit inclination (24 deg). Note the (minimum) 3 upper stage burns, last burn apparently being to depletion.
edit: forgot DSX payload mass
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Description of DSCOVR payload: https://www.fbo.gov/utils/view?id=168229cf3e11961a9b8324a5dc8f80d3
Description of STP-2 payload: https://www.fbo.gov/utils/view?id=36de6af7670d2636c8c195173dd500e1
Good stuff.
Very good stuff. From the second:
"This document provides the requirements for Sample Mission 2.4 (SM-2.4) to be conducted under the Orbital Suborbital Program-3 (OSP-3) contract.
The baseline launch location for this mission will be from the East Coast of the United States.
The Initial Launch Capability (ILC) is August 2015."
A Falcon Heavy launch from the East Coat by 8/2015?
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Blah! My e-mail still being slow with some press releases? :( Jacques beats me on NASA stuff by 30 mins! ;D
So AvWeek have an article on. I'll still look at doing one too as they were mainly about beating Orbital.....
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SpaceX, Ten-HUT! You have been selected for basic training...
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SpaceX, Ten-HUT! You have been selected for basic training...
Been there, done that......no sweat. ;)
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Hmm..... according to Gunter's site, COSMIC-2 (a.k.a. FORMOSAT 7 of Taiwan) was previously booked on 2 Minotaur-4 launches (http://space.skyrocket.de/doc_sdat/formosat-7-cosmic-2.htm), while DSX was previously paired with the next DMSP launch in 2014 (http://space.skyrocket.de/doc_sdat/dsx.htm). What caused the change to FH?
Anyway that seems to be another win for SpaceX! :)
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Hmm..... according to Gunter's site, COSMIC-2 (a.k.a. FORMOSAT 7 of Taiwan)...
(http://space.skyrocket.de/doc_sdat/formosat-7-cosmic-2.htm)
Is that the NSPO mission on the SpaceX manifest?
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Hmm..... according to Gunter's site, COSMIC-2 (a.k.a. FORMOSAT 7 of Taiwan)...
(http://space.skyrocket.de/doc_sdat/formosat-7-cosmic-2.htm)
Is that the NSPO mission on the SpaceX manifest?
Nope, that's FORMOSAT 5 (http://space.skyrocket.de/doc_sdat/formosat-5.htm).
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SpaceX, Ten-HUT! You have been selected for basic training...
Been there, done that......no sweat. ;)
No sweat? You ain't doing it right, son. :D
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Patch collection now available in SpaceX shop.
I just bought mine. It'll be a nice stocking stuffer... for myself. :)
http://shop.spacex.com/collections/hats-accessories/products/mission-patch-collection
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Aerospace America has some possibly-new information on the SuperDraco testing:
-more than 45 firings
-89 seconds total
-20-100% throttling
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Patch collection now available in SpaceX shop.
I just bought mine. It'll be a nice stocking stuffer... for myself. :)
http://shop.spacex.com/collections/hats-accessories/products/mission-patch-collection
They're all sold out now :(
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Aerospace America has some possibly-new information on the SuperDraco testing:
-more than 45 firings
-89 seconds total
-20-100% throttling
Link?
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Aerospace America has some possibly-new information on the SuperDraco testing:
-more than 45 firings
-89 seconds total
-20-100% throttling
Link?
You have to be an AIAA member. It's in the December issue.
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Forget about North Korea. The private space wars have begun LOL. SpaceX was seen driving a billboard truck around Mojave streets looking for workers.
http://www.parabolicarc.com/2012/12/12/spacex-visits-mojave/
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SpaceX water paints.
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Has there been any recent news out of SLC-4? Are they on schedule? Pictures would be fun.
Rob
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Has there been any recent news out of SLC-4? Are they on schedule? Pictures would be fun.
Rob
I looked through the local newspaper website
http://www.lompocrecord.com/news/local/military/vandenberg/ (http://www.lompocrecord.com/news/local/military/vandenberg/)
and looked as far back as September and there hasn't been any local news about SpaceX or SLC-4.
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Has there been any recent news out of SLC-4? Are they on schedule? Pictures would be fun.
Rob
I looked through the local newspaper website
http://www.lompocrecord.com/news/local/military/vandenberg/ (http://www.lompocrecord.com/news/local/military/vandenberg/)
and looked as far back as September and there hasn't been any local news about SpaceX or SLC-4.
Thanks for looking!
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Has there been any recent news out of SLC-4? Are they on schedule? Pictures would be fun.
Rob
I looked through the local newspaper website
http://www.lompocrecord.com/news/local/military/vandenberg/ (http://www.lompocrecord.com/news/local/military/vandenberg/)
and looked as far back as September and there hasn't been any local news about SpaceX or SLC-4.
this is the space age, who has a Sat over it? Google maybe?
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Has there been any recent news out of SLC-4? Are they on schedule? Pictures would be fun.
Rob
I looked through the local newspaper website
http://www.lompocrecord.com/news/local/military/vandenberg/ (http://www.lompocrecord.com/news/local/military/vandenberg/)
and looked as far back as September and there hasn't been any local news about SpaceX or SLC-4.
this is the space age, who has a Sat over it? Google maybe?
Military base, they don't update the images of those with anything like the regularity of non military images... and you can't contract for a keyhole image of a US military base... for obvious reasons. Google maps stills shows a Titan pad there :).
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Has there been any recent news out of SLC-4?
Well, Cassiope is scheduled to launch NET April 2013 at the moment, so they still have plenty of time. The last I saw (October/November), the HIF was already under construction as was the pad itself.
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Military base, they don't update the images of those with anything like the regularity of non military images... and you can't contract for a keyhole image of a US military base... for obvious reasons. Google maps stills shows a Titan pad there :).
Ain't that the truth? I live next to, (work on) Hill AFB and last time a looked (about a year ago) google maps had "pictures" of the place where my apartment complex is/was showing Korea era tanks-and-trucks in a wrecking yard and the Hill flight line was supporting what looked like a couple of B-17s and maybe an F-84 or two :)
Now the ROADS were all in the right places which made things look a bit funny considering the access gates have changed and every ELSE was 'normal' as long as you were a couple of miles away from the base :)
Randy
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Has there been any recent news out of SLC-4? Are they on schedule? Pictures would be fun.
Rob
I looked through the local newspaper website
http://www.lompocrecord.com/news/local/military/vandenberg/ (http://www.lompocrecord.com/news/local/military/vandenberg/)
and looked as far back as September and there hasn't been any local news about SpaceX or SLC-4.
this is the space age, who has a Sat over it? Google maybe?
Military base, they don't update the images of those with anything like the regularity of non military images... and you can't contract for a keyhole image of a US military base... for obvious reasons. Google maps stills shows a Titan pad there :).
On a whim I tried baidu maps thinking the chinese might offer it, but nope, if its not china they don't have any maps closer in than a national scale.
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Has there been any recent news out of SLC-4? Are they on schedule? Pictures would be fun.
Rob
I looked through the local newspaper website
http://www.lompocrecord.com/news/local/military/vandenberg/ (http://www.lompocrecord.com/news/local/military/vandenberg/)
and looked as far back as September and there hasn't been any local news about SpaceX or SLC-4.
this is the space age, who has a Sat over it? Google maybe?
Military base, they don't update the images of those with anything like the regularity of non military images... and you can't contract for a keyhole image of a US military base... for obvious reasons. Google maps stills shows a Titan pad there :).
For $25 you can buy an image from 2012/1/18 http://www.terraserver.com/view.asp?cx=-120.613393&cy=34.632706&proj=4326&mpp=2.5&pic=img (http://www.terraserver.com/view.asp?cx=-120.613393&cy=34.632706&proj=4326&mpp=2.5&pic=img)
And if you pay enough dough you can ask DigitalGlobe (http://www.digitalglobe.com/purchase) to make an image especially for you. These guys (http://www.dreamlandresort.com/) even do it every two years for Area 51.
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Military base, they don't update the images of those with anything like the regularity of non military images... and you can't contract for a keyhole image of a US military base... for obvious reasons. Google maps stills shows a Titan pad there :).
Ain't that the truth? I live next to, (work on) Hill AFB and last time a looked (about a year ago) google maps had "pictures" of the place where my apartment complex is/was showing Korea era tanks-and-trucks in a wrecking yard and the Hill flight line was supporting what looked like a couple of B-17s and maybe an F-84 or two :)
Now the ROADS were all in the right places which made things look a bit funny considering the access gates have changed and every ELSE was 'normal' as long as you were a couple of miles away from the base :)
Randy
lol, maybe those are the same pics Jim has.
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Has there been any recent news out of SLC-4? Are they on schedule? Pictures would be fun.
Rob
I looked through the local newspaper website
http://www.lompocrecord.com/news/local/military/vandenberg/ (http://www.lompocrecord.com/news/local/military/vandenberg/)
and looked as far back as September and there hasn't been any local news about SpaceX or SLC-4.
this is the space age, who has a Sat over it? Google maybe?
Military base, they don't update the images of those with anything like the regularity of non military images... and you can't contract for a keyhole image of a US military base... for obvious reasons. Google maps stills shows a Titan pad there :).
For $25 you can buy an image from 2012/1/18 http://www.terraserver.com/view.asp?cx=-120.613393&cy=34.632706&proj=4326&mpp=2.5&pic=img (http://www.terraserver.com/view.asp?cx=-120.613393&cy=34.632706&proj=4326&mpp=2.5&pic=img)
And if you pay enough dough you can ask DigitalGlobe (http://www.digitalglobe.com/purchase) to make an image especially for you. These guys (http://www.dreamlandresort.com/) even do it every two years for Area 51.
sounds like the perfect kickstarter to me....
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http://www.livescience.com/25915-private-space-travel-leaps-2013.html
“Dragon Version 2 won’t look like [today’s Dragon]. I think it looks pretty cool. Dragon one, we didn’t really know what we were doing so that’s why Dragon looks similar to things that have happened in the past,” SpaceX founder Elon Musk told an audience during a talk at the UK’s Royal Aeronautical Society in London on Nov. 21. Musk described Dragon version 2 as having “legs that pop out” and added that it uses parachutes and its eight SuperDraco thrusters for a “propulsive landing”.
What will Dragon2 look like? It sounds like it will look more or less the same - sort of like what we saw in that "We Will Be Victorious" music video. Will this Dragon2 with propulsive landing make an appearance prior to F9R?
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http://www.livescience.com/25915-private-space-travel-leaps-2013.html
“Dragon Version 2 won’t look like [today’s Dragon]. I think it looks pretty cool. Dragon one, we didn’t really know what we were doing so that’s why Dragon looks similar to things that have happened in the past,” SpaceX founder Elon Musk told an audience during a talk at the UK’s Royal Aeronautical Society in London on Nov. 21. Musk described Dragon version 2 as having “legs that pop out” and added that it uses parachutes and its eight SuperDraco thrusters for a “propulsive landing”.
What will Dragon2 look like? It sounds like it will look more or less the same - sort of like what we saw in that "We Will Be Victorious" music video. Will this Dragon2 with propulsive landing make an appearance prior to F9R?
The vehicle from the reusable Falcon video is Dragonrider, the crewed Dragon. I don't think that anyone outside SpaceX knows what "Dragon-2" looks like yet.
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http://www.livescience.com/25915-private-space-travel-leaps-2013.html
“Dragon Version 2 won’t look like [today’s Dragon]. I think it looks pretty cool. Dragon one, we didn’t really know what we were doing so that’s why Dragon looks similar to things that have happened in the past,” SpaceX founder Elon Musk told an audience during a talk at the UK’s Royal Aeronautical Society in London on Nov. 21. Musk described Dragon version 2 as having “legs that pop out” and added that it uses parachutes and its eight SuperDraco thrusters for a “propulsive landing”.
What will Dragon2 look like? It sounds like it will look more or less the same - sort of like what we saw in that "We Will Be Victorious" music video. Will this Dragon2 with propulsive landing make an appearance prior to F9R?
Thread is here:
http://forum.nasaspaceflight.com/index.php?topic=30455.msg983579#msg983579
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http://www.livescience.com/25915-private-space-travel-leaps-2013.html
“Dragon Version 2 won’t look like [today’s Dragon]. I think it looks pretty cool. Dragon one, we didn’t really know what we were doing so that’s why Dragon looks similar to things that have happened in the past,” SpaceX founder Elon Musk told an audience during a talk at the UK’s Royal Aeronautical Society in London on Nov. 21. Musk described Dragon version 2 as having “legs that pop out” and added that it uses parachutes and its eight SuperDraco thrusters for a “propulsive landing”.
What will Dragon2 look like? It sounds like it will look more or less the same - sort of like what we saw in that "We Will Be Victorious" music video. Will this Dragon2 with propulsive landing make an appearance prior to F9R?
Thread is here:
http://forum.nasaspaceflight.com/index.php?topic=30455.msg983579#msg983579
I am fairly confident the Dragon 2 will appear before the fully reusable Falcon 9.
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http://www.livescience.com/25915-private-space-travel-leaps-2013.html
“Dragon Version 2 won’t look like [today’s Dragon]. I think it looks pretty cool. Dragon one, we didn’t really know what we were doing so that’s why Dragon looks similar to things that have happened in the past,” SpaceX founder Elon Musk told an audience during a talk at the UK’s Royal Aeronautical Society in London on Nov. 21. Musk described Dragon version 2 as having “legs that pop out” and added that it uses parachutes and its eight SuperDraco thrusters for a “propulsive landing”.
What will Dragon2 look like? It sounds like it will look more or less the same - sort of like what we saw in that "We Will Be Victorious" music video. Will this Dragon2 with propulsive landing make an appearance prior to F9R?
This is old info and here's a link to the video the quote was taken from.
https://www.youtube.com/watch?v=wB3R5Xk2gTY&t=19m20s
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Update shows how SLC-4E looks:
https://twitter.com/SpaceX (https://twitter.com/SpaceX)
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Can anyone pick out anything of significance? My untrained eye can't really see anything interesting.
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The first of the lightning towers looks to be up and I'm assuming those are RP-1 tanks.
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The first of the lightning towers looks to be up and I'm assuming those are RP-1 tanks.
That tower is preexisting. I don't think it's for lightning.
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Update shows how SLC-4E looks:
https://twitter.com/SpaceX (https://twitter.com/SpaceX)
Either:
A) Thanks, Padrat!
or
B) That was quite a coincidence.
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A little confused by what I'm seeing. Several things, what is the vertical structure? Where is the assembly building and what are the features at the far right?
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A little confused by what I'm seeing. Several things, what is the vertical structure? Where is the assembly building and what are the features at the far right?
Vertical structure is leftover from Titan at the west pad. Its east counterpart was demolished. I don't think the HIF is in the picture, could be behind a hill.
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The first of the lightning towers looks to be up and I'm assuming those are RP-1 tanks.
That tower is preexisting. I don't think it's for lightning.
If it was there before it's a communications tower. It is a little far from the pad.
The HIF is hidden behind the hill on the right side. Here is a picture from last year. http://www.facebook.com/photo.php?fbid=10152114539425131&set=pb.353851465130.-2207520000.1357355786&type=3&theater (http://www.facebook.com/photo.php?fbid=10152114539425131&set=pb.353851465130.-2207520000.1357355786&type=3&theater)
(http://sphotos-a.xx.fbcdn.net/hphotos-frc1/483067_10152114539425131_451918161_n.jpg)
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http://wikimapia.org/#lat=34.6326737&lon=-120.6081506&z=17&l=0&m=b
Did a little map update on wikimapia showing the location of all the photos we have seen to date of the Vandenburg construction site.
Am I missing something? How is SpaceX going to have a straight shot from their hanger to the launch pad, also it seems like the hanger is uphill of the launch site, is there any other rocket that goes up/down hill from it's hanger to it's pad?
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I don't think they need a straight shot... There have been hints from some on this forum that they will not use a rail system to move the LV from the assembly building to the pad. But no official indication yet.
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I seem to remember that one forum member said they would use a rail system. But I agree it's unknown at the moment. There's no reason why the tracks can't curve as long as the rail bogies can pivot. On the other hand a road transporter like Antares or Delta IV seems perfectly viable as well.
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http://wikimapia.org/#lat=34.6326737&lon=-120.6081506&z=17&l=0&m=b
Did a little map update on wikimapia showing the location of all the photos we have seen to date of the Vandenburg construction site.
Am I missing something? How is SpaceX going to have a straight shot from their hanger to the launch pad, also it seems like the hanger is uphill of the launch site, is there any other rocket that goes up/down hill from it's hanger to it's pad?
LC-39 requires the rocket to go up a significant slope.
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The rocket goes up a small incline at 40...
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.... is there any other rocket that goes up/down hill from it's hanger to it's pad?
Antares will go uphill.
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Thanks guys, I have only really seen launch pads for MLV+ rockets from photos, never actually been to one. Thanks!
Can't wait for more images of Vandenberg launch site.
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I seem to remember that one forum member said they would use a rail system. But I agree it's unknown at the moment. There's no reason why the tracks can't curve as long as the rail bogies can pivot. On the other hand a road transporter like Antares or Delta IV seems perfectly viable as well.
My understanding was that a KAMAG transporter, or something like it, was going to be used.
- Ed Kyle
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I attempted some annotation of the new image.
I am relatively sure they took this picture specifically avoiding any of the new infrastructure. It's all hidden behind the hill in the foreground which is right where the pad is. And the large hanger is off to the right beyond the edge of the image.
The mentioned "antenna" is also closer to SLC-4W rather than SLC-4E.
Edit: Also added google maps version of the image showing the same locations and the rough field of view of the image.
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Some old pics and the reference to an old post of KSC Sage:
.....It will look and operate similar to the Delta IV SLC-37 erector system.
http://forum.nasaspaceflight.com/index.php?topic=24711.msg969863#msg969863
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Netzsch Instruments weighs in as a SpaceX supplier -
http://www.rdmag.com/news/2013/01/netzsch-supply-spacex’s-thermal-analysis-laboratory-instruments
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Elon Musk to speak at TED on February 27th:
http://conferences.ted.com/TED2013/program/guide.php
I have no idea what his topic will be. But, these TED talks are almost always entertaining and informative.
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Elon Musk to speak at TED on February 27th:
I noticed on your link that he's got a website. http://elonmusk.com/
Funny twitter post about the "kale-eating overlord of Mars" :)
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Elon Musk to speak at TED on February 27th:
I noticed on your link that he's got a website. http://elonmusk.com/
Funny twitter post about the "kale-eating overlord of Mars" :)
I thought you meant this one: http://shitelonsays.com/ ;)
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I don't know if this image has been posted already before but it's kind of cool.
http://www.nasa.gov/exploration/commercial/crew/space-exploration-three.html
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Good find. This is the manned Dragon with SuperDracos on the side!
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Good find. This is the manned Dragon with SuperDracos on the side!
It is a (early ?)mockup of it
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Yep, that mockup has been seen in pictures from SpaceX for a while.
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CRS-8 will be launching with Bigelow's BEAM mission module for ISS in Dragon trunk.
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CRS-8 will be launching with Bigelow's BEAM mission module for ISS in Dragon trunk.
And that's how it is going to look like ;)
http://www.youtube.com/watch?v=d1u1Vl9X_gY
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Good find. This is the manned Dragon with SuperDracos on the side!
There is another picture (with Tim Hughes) of the same mockup here at the same event:
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And here is one with Musk & Bolden, from 6 months ago: (after the C2 mission)
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CRS-8 will be launching with Bigelow's BEAM mission module for ISS in Dragon trunk.
Excuse the question, but what is your source for this?
Do you have a list of what is going on which CRS flight?
I have a particular interest in SAGE-III, and was told that it was scheduled for CRS-6. Can you confirm, deny, or correct that?
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Sorry, Comga, but they mentioned that tidbit about CRS-8 specifically during the presser about BEAM today.
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Interested in software upgrades for future CRS missions. Any chance of possible upgrade to cargo Dragon considering the problems the Dragon capsule had last flight. Have not heard anything since the last story here at nasaspaceflight.com
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Interested in software upgrades for future CRS missions. Any chance of possible upgrade to cargo Dragon considering the problems the Dragon capsule had last flight. Have not heard anything since the last story here at nasaspaceflight.com
Of course they'd make changes.
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New photos from Vandenberg:
http://spacexlaunch.zenfolio.com/p368447768
New strongback under construction?
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New photos from Vandenberg:
http://spacexlaunch.zenfolio.com/p368447768
New strongback under construction?
Sure looks like it. I don't see any rails in the floor. Makes me think it's going to the pad on some kind of wheeled rig?
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it is sweet to finally see evidence on the pad for the FH mount... As expected, it lines up with how the Titan IV was aligned on the flame trench. The flame trench is getting some restoration/enhancement done as well.
It looks like the new wheeled(?) rig that delivers the strongback + F9/FH will be very wide, to straddle the right-most flame duct as it comes in from the right. (there is a flame duct exit on the other side of the pad too)
EDIT: I have attached a zoomed in view.
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http://www.floridatoday.com/article/20130117/SPACE03/130117013/NASA-confident-SpaceX-engines-ready-March-launch?nclick_check=1
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http://www.floridatoday.com/article/20130117/SPACE03/130117013/NASA-confident-SpaceX-engines-ready-March-launch?nclick_check=1
Very interesting, but this should probably go in a separate thread, or the general discussion thread, or even better the CRS2 updates thread: http://forum.nasaspaceflight.com/index.php?topic=30700.0
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Suffredini said a significant amount of pre-launch testing may have contributed to the early shutdown of one of nine Falcon 9 engines during the Oct. 7 launch of an unmanned cargo resupply mission.
That doesn't sound very reasuring if reusability of Merlin engines is to eventually be the goal. Fortunately, this is the last flight with a Merlin 1C...
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Don't change the thread title. This one has a thread title already, for a reason.
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Suffredini said a significant amount of pre-launch testing may have contributed to the early shutdown of one of nine Falcon 9 engines during the Oct. 7 launch of an unmanned cargo resupply mission.
That doesn't sound very reasuring if reusability of Merlin engines is to eventually be the goal. Fortunately, this is the last flight with a Merlin 1C...
kerosene-burning engines still produce enough residues that their operational lifetimes are limited. you wouldn't have this problem whit CH4 so maybe we will see a CH4 engine sooner rather than later from spacex
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Suffredini said a significant amount of pre-launch testing may have contributed to the early shutdown of one of nine Falcon 9 engines during the Oct. 7 launch of an unmanned cargo resupply mission.
That doesn't sound very reasuring if reusability of Merlin engines is to eventually be the goal. Fortunately, this is the last flight with a Merlin 1C...
kerosene-burning engines still produce enough residues that their operational lifetimes are limited. you wouldn't have this problem whit CH4 so maybe we will see a CH4 engine sooner rather than later from spacex
But soot seems not to be the problem, if the fuel dome failed. That might be more of a resonance problem which would be different on the test stand than in flight. I am sure they run simulations and test runs with Merlin 1D now and may come up with minor alterations of the fuel dome to alleviate the problem. If it is not already altered on Merlin 1D.
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Suffredini said a significant amount of pre-launch testing may have contributed to the early shutdown of one of nine Falcon 9 engines during the Oct. 7 launch of an unmanned cargo resupply mission.
Incidentally, here is the press conference where Suffredini mentionned this:
http://www.youtube.com/watch?v=0DM750sNj8g&feature=player_embedded
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Possibly this indicates the first solid data towards calculating a maximum burn 'lifespan' of a Merlin-1c (before the stresses on the engine cause it to fail).
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Possibly this indicates the first solid data towards calculating a maximum burn 'lifespan' of a Merlin-1c (before the stresses on the engine cause it to fail).
And you don't think SpaceX has tested enough Merlin 1Cs to have better data? They test rocket engines all the time at McGregor.
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Regarding the new photos of the new FH launch pad at Vandenberg, I wonder if the large concrete trench to the right of the launch mount will house an erection mechanism similar to the one used to erect the Delta IV at SLC37. Photo's attached
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Possibly this indicates the first solid data towards calculating a maximum burn 'lifespan' of a Merlin-1c (before the stresses on the engine cause it to fail).
And you don't think SpaceX has tested enough Merlin 1Cs to have better data? They test rocket engines all the time at McGregor.
Maybe and maybe not. As far as anyone knows, have they ever purposely run a rocket until it 'explosively deconstructs'? This might be the very first data-point of that kind.
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Possibly this indicates the first solid data towards calculating a maximum burn 'lifespan' of a Merlin-1c (before the stresses on the engine cause it to fail).
And you don't think SpaceX has tested enough Merlin 1Cs to have better data? They test rocket engines all the time at McGregor.
Maybe and maybe not. As far as anyone knows, have they ever purposely run a rocket until it 'explosively deconstructs'? This might be the very first data-point of that kind.
Yes, I'm sure this is the first time they've tried.
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Yes, I'm sure this is the first time they've tried.
Hmm, what speaks against that is that SpaceX employees seemingly had developed a tongue in cheek description for the event as "RUD", rapid unexpected disassembly. But then, they might have just done that in anticipation of such an event?
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Regarding the new photos of the new FH launch pad at Vandenberg, I wonder if the large concrete trench to the right of the launch mount will house an erection mechanism similar to the one used to erect the Delta IV at SLC37. Photo's attached
To me, this seems more plausible than an additional exit for the flame trench. I wonder if this erection mechanism is what is shown under construction in the hangar photo.
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Possibly this indicates the first solid data towards calculating a maximum burn 'lifespan' of a Merlin-1c (before the stresses on the engine cause it to fail).
And you don't think SpaceX has tested enough Merlin 1Cs to have better data? They test rocket engines all the time at McGregor.
Maybe and maybe not. As far as anyone knows, have they ever purposely run a rocket until it 'explosively deconstructs'? This might be the very first data-point of that kind.
Not a whole rocket, but they have certainly run individual engines until they fail.
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Regarding the new photos of the new FH launch pad at Vandenberg, I wonder if the large concrete trench to the right of the launch mount will house an erection mechanism similar to the one used to erect the Delta IV at SLC37. Photo's attached
To me, this seems more plausible than an additional exit for the flame trench. I wonder if this erection mechanism is what is shown under construction in the hangar photo.
it is possible, but I doubt it. Because that trench as FAR deeper than it would have to be to mount a relatively simple erection mechanism. Also note that the launch mount is much higher, so the two ramps on each side will likely be built even higher to allow the rocket to be rolled right up to the current concrete level of the pad mount.
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Suffredini said a significant amount of pre-launch testing may have contributed to the early shutdown of one of nine Falcon 9 engines during the Oct. 7 launch of an unmanned cargo resupply mission.
Incidentally, here is the press conference (https://www.youtube.com/watch?v=0DM750sNj8g&feature=player_embedded) where Suffredini mentioned this
My transcription from 42:55 in the video:
The SpaceX engine anomaly. First of all it's not completely closed, there is still some work to wrap up and do the final closure, and we'll get into the details at the right time - we'll do that with our SpaceX colleagues that actually own that system, and there's some sensitivities in all of this that we try to avoid. But I can tell you that a very thorough review was conducted, there was an enormous amount of data provided, that the NASA engine guys, structure guys, propulsion system guys all participated with the SpaceX team to review the anomaly. As is often the case, with a failure like this on a system you don't get back, it was hard to find a specific smoking gun to point to. But a number of things were believed to be contributors that have been looked at, and the engines actually have been re-examined, NDE examinations, to confirm the health of the engines that are about to fly. In addition to that, a contributing factor was perhaps the amount of testing that this engine and engine 2 on that same vehicle saw before it flew - although it was certified and in all the testing it went through, none of those tests violated any of the design criteria of the engine, it's possible that the amount of testing they were exposed to might have been a contributing factor. And these engines flying on this next flight are all new engines that have been acceptance tested but really have not participated in other test programs. So the combination of the failure investigation, what legs of the fault tree were remaining, the extra NDE that's been done to these engines, and the fact that these engines from a test-time standpoint have very low additional test-time on them, other than what is necessary to certify the engine for flight, will help us conclude that the engines we have on this particular SpaceX flight are good to go. Again we haven't officially determined that - the NDE work is concluded but the review of the data is not, so that work needs to wrap up and then there'll be a more formal report at the end.
(emphasis added)
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Regarding the new photos of the new FH launch pad at Vandenberg, I wonder if the large concrete trench to the right of the launch mount will house an erection mechanism similar to the one used to erect the Delta IV at SLC37. Photo's attached
To me, this seems more plausible than an additional exit for the flame trench. I wonder if this erection mechanism is what is shown under construction in the hangar photo.
Old pic, and post of KSC sage regarding this.
http://forum.nasaspaceflight.com/index.php?topic=24711.msg969863#msg969863
He says: "It will look and operate similar to the Delta IV SLC-37 erector system."
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Hmm, yep, that picture definitely seems to indicate that this dug out area is not part of the flame trench. (since there appears to be no opening through to it in the back)
Here is a better picture of the SLC-37 Delta IV mechanism, it certainly matches up with what SpaceX is constructing:
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And that structure being built inside the hanger looks similar to the DeltaIV strong back as CorrodedNut suggested.
edit: until Lars_J added the last picture that is :)
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Picture I have not seen before, posted on SpaceX's facebook:
Great photo of NASA astronauts with Falcon 9, helping prepare cargo for Dragon's next trip to station.
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I wonder how the tire tracks ended up on the interstage. :)
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I wonder how the tire tracks ended up on the interstage. :)
Oh darn, I forget what they're called but on SRB we had these stands they'd put the boosters on that allowed them to be rotated for inspection, and the booster actually rested on a belt. I could imagine those making the same kind of mark.
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Picture I have not seen before, posted on SpaceX's facebook:
Great photo of NASA astronauts with Falcon 9, helping prepare cargo for Dragon's next trip to station.
Would astronauts normally get to hang around the rockets in production? I'd think they'd have a great time at SpaceX.
With regard to tire marks - and those marks do look very much like standard tire treads - clearly the Falcon at the stage of processing pictured is being turned on fitted rings, so the tire marks had to be made somewhat earlier, but after the paint job.
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It might just be from some sort of carrying frame that rests the trunk on tires to allow it to rotate before being attached to the stages.
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Would astronauts normally get to hang around the rockets in production? I'd think they'd have a great time at SpaceX.
Why?
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Picture I have not seen before, posted on SpaceX's facebook:
Great photo of NASA astronauts with Falcon 9, helping prepare cargo for Dragon's next trip to station.
Would astronauts normally get to hang around the rockets in production? I'd think they'd have a great time at SpaceX.
I suspect the purpose of that visit was evaluation of the manned Dragon crew cabin, not to hang around the Falcon. Some of the astronauts in that picture have been photographed in the Dragon cabin before. They did the Falcon 9 photo-op because SpaceX builds everything in the same building.
In the shuttle era, astronauts did plant visits to Michoud, ATK, and Rocketdyne on a fairly regular basis, and the practice goes back all the way to Mercury. It's not new.
You do know the picture is from SLC-40, right?
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Would astronauts normally get to hang around the rockets in production? I'd think they'd have a great time at SpaceX.
Why?
Because astronauts are geeks, just like us, who would in general have a great time hanging out with technology related stuff???
(Yes, that pic wasn't taken in Cali at the plant, I'm just answering Jim's "why?" )
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Suffredini said a significant amount of pre-launch testing may have contributed to the early shutdown of one of nine Falcon 9 engines during the Oct. 7 launch of an unmanned cargo resupply mission.
Incidentally, here is the press conference (https://www.youtube.com/watch?v=0DM750sNj8g&feature=player_embedded) where Suffredini mentioned this
My transcription from 42:55 in the video:
The SpaceX engine anomaly. First of all it's not completely closed, there is still some work to wrap up and do the final closure, and we'll get into the details at the right time - we'll do that with our SpaceX colleagues that actually own that system, and there's some sensitivities in all of this that we try to avoid. But I can tell you that a very thorough review was conducted, there was an enormous amount of data provided, that the NASA engine guys, structure guys, propulsion system guys all participated with the SpaceX team to review the anomaly. As is often the case, with a failure like this on a system you don't get back, it was hard to find a specific smoking gun to point to. But a number of things were believed to be contributors that have been looked at, and the engines actually have been re-examined, NDE examinations, to confirm the health of the engines that are about to fly. In addition to that, a contributing factor was perhaps the amount of testing that this engine and engine 2 on that same vehicle saw before it flew - although it was certified and in all the testing it went through, none of those tests violated any of the design criteria of the engine, it's possible that the amount of testing they were exposed to might have been a contributing factor. And these engines flying on this next flight are all new engines that have been acceptance tested but really have not participated in other test programs. So the combination of the failure investigation, what legs of the fault tree were remaining, the extra NDE that's been done to these engines, and the fact that these engines from a test-time standpoint have very low additional test-time on them, other than what is necessary to certify the engine for flight, will help us conclude that the engines we have on this particular SpaceX flight are good to go. Again we haven't officially determined that - the NDE work is concluded but the review of the data is not, so that work needs to wrap up and then there'll be a more formal report at the end.
(emphasis added)
Appreciated, thanks.
Cheers, Martin
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Would astronauts normally get to hang around the rockets in production? I'd think they'd have a great time at SpaceX.
Why?
Because astronauts are geeks, just like us, who would in general have a great time hanging out with technology related stuff???
Been around them enough to say they wouldn't.
Never had an astronaut come over to see an unmanned spacecraft, even though it was onsite (like MSL) or a few miles away at Astrotech.
a. they are too busy. They rarely "hang" around
b. It is a cargo hauler (boring to them)
c. There is nothing there that has a rotational or translational hand controller.
They only were at Spacex because it might eventually be a ride to space for them, not because it is technology related stuff
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Would astronauts normally get to hang around the rockets in production? I'd think they'd have a great time at SpaceX.
Why?
Because astronauts are geeks, just like us, who would in general have a great time hanging out with technology related stuff???
Been around them enough to say they wouldn't.
Never had an astronaut come over to see an unmanned spacecraft, even though it was onsite (like MSL) or a few miles away at Astrotech.
a. they are too busy. They rarely "hang" around
b. It is a cargo hauler (boring to them)
c. There is nothing there that has a rotational or translational hand controller.
They only were at Spacex because it might eventually be a ride to space for them, not because it is technology related stuff
Astronauts Andre Kuipers and Don Petit visited the SpaceX plant multiple times and went inside Dragon capsules multiple times in preparation for their Expedition 30/31 mission. "Boring" as the cargo capsules may be they still had to work with this spacecraft during their stay on ISS.
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Astronauts Andre Kuipers and Don Petit visited the SpaceX plant multiple times and went inside Dragon capsules multiple times in preparation for their Expedition 30/31 mission. "Boring" as the cargo capsules may be they still had to work with this spacecraft during their stay on ISS.
That is a standard practice. Astronauts did the same thing for Spacehab cargo flights.
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New picture of SLC-4E from Google Earth taken June 7th, but they just added recently.
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Appreciated, thanks.
Cheers, Martin
You're welcome - punctuating Suffredini is a sport all to itself. :)
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Would astronauts normally get to hang around the rockets in production? I'd think they'd have a great time at SpaceX.
Why?
Because astronauts are geeks, just like us, who would in general have a great time hanging out with technology related stuff???
Been around them enough to say they wouldn't.
Never had an astronaut come over to see an unmanned spacecraft, even though it was onsite (like MSL) or a few miles away at Astrotech.
a. they are too busy. They rarely "hang" around
b. It is a cargo hauler (boring to them)
c. There is nothing there that has a rotational or translational hand controller.
They only were at Spacex because it might eventually be a ride to space for them, not because it is technology related stuff
Well thanks for the perspective, Jim. How sad. I guess I'm not astronaut material for yet ANOTHER reason :) (I think I'm up to 39 reasons now)
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I think the Astros were there just for a general visit of the facility. Got to look around the vehicle/inside Dragon. I was too busy that day to see many of the names, didn't really recognize any of them other than all navy except for one I believe.
As far as the tire tracks, I asked about it as well. No one here really knew how other than it came from Cali that way. Probably from some tooling at some point.
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Astronauts Andre Kuipers and Don Petit visited the SpaceX plant multiple times and went inside Dragon capsules multiple times in preparation for their Expedition 30/31 mission. "Boring" as the cargo capsules may be they still had to work with this spacecraft during their stay on ISS.
That is a standard practice. Astronauts did the same thing for Spacehab cargo flights.
Yes, I know. Doesn't at least a part of your experience with astronauts come from those very Spacehab cargo flights?
Serious question Jim: Did the astronauts find the activities for those Spacehab cargo flights boring?
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Well, they knew they were never going to get ice cream out of SpaceHab... ;)
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Well, they knew they were never going to get ice cream out of SpaceHab... ;)
But they did get some pop (soda/coke for those not in the Midwest/Northwest/Rustbelt) out of a Spacelab mission!
http://en.wikipedia.org/wiki/STS-51-F
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Well, they knew they were never going to get ice cream out of SpaceHab... ;)
Flew ice cream a few times
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As far as the tire tracks, I asked about it as well. No one here really knew how other than it came from Cali that way. Probably from some tooling at some point.
I'll bet it's from the new Anti-Gravity Segway (AGS), that Elon's invented. They've been testing it late at night in the Hawthorne factory, but I hear the controls are a little twitchy. 8)
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Corrodednut linked to these set of images in the SpX-2 update thread, which showed CRS2 hardware arriving back in November:
http://mediaarchive.ksc.nasa.gov/search.cfm?cat=225
These images also happen to be one of the first set public images (to my knowledge) that shows the interior if the two new "high bays" that SpaceX added to the SLC-40 integration building last year. (see attached pictures)
I'm also attaching a picture of the 1st stage transport rig - yep, definitely oversize. :)
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Either they want it to warm under the sun or those SpaceX packers have a dirty mind :D
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Corrodednut linked to these set of images in the SpX-2 update thread, which showed CRS2 hardware arriving back in November:
http://mediaarchive.ksc.nasa.gov/search.cfm?cat=225
These images also happen to be one of the first set public images (to my knowledge) that shows the interior if the two new "high bays" that SpaceX added to the SLC-40 integration building last year. (see attached pictures)
I'm also attaching a picture of the 1st stage transport rig - yep, definitely oversize. :)
Thanks for the pictures. Does anyone know why the inside of the high bay has those white stripes on the walls? Will it be fully painted eventually?
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Corrodednut linked to these set of images in the SpX-2 update thread, which showed CRS2 hardware arriving back in November:
http://mediaarchive.ksc.nasa.gov/search.cfm?cat=225
These images also happen to be one of the first set public images (to my knowledge) that shows the interior if the two new "high bays" that SpaceX added to the SLC-40 integration building last year. (see attached pictures)
I'm also attaching a picture of the 1st stage transport rig - yep, definitely oversize. :)
Thanks for the pictures. Does anyone know why the inside of the high bay has those white stripes on the walls? Will it be fully painted eventually?
That looks like caulk(sp?) between dry-wall pieces, like you would see in any unfinished residential or commercial building. I would assume it would be painted at some point, if they want to cut down on dust.
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Corrodednut linked to these set of images in the SpX-2 update thread, which showed CRS2 hardware arriving back in November:
http://mediaarchive.ksc.nasa.gov/search.cfm?cat=225
These images also happen to be one of the first set public images (to my knowledge) that shows the interior if the two new "high bays" that SpaceX added to the SLC-40 integration building last year. (see attached pictures)
I'm also attaching a picture of the 1st stage transport rig - yep, definitely oversize. :)
Thanks for the pictures. Does anyone know why the inside of the high bay has those white stripes on the walls? Will it be fully painted eventually?
That looks like caulk(sp?) between dry-wall pieces, like you would see in any unfinished residential or commercial building. I would assume it would be painted at some point, if they want to cut down on dust.
I would say what we are seeing is far from complete. Unless it has snowed in central Florida the floor is covered in drywall dust. Cleaning up the mess that trailer tracked on the floor in the existing hangar must have been fun.
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Either they want it to warm under the sun or those SpaceX packers have a dirty mind :D
They're just practising safe SpaceX.
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Those pics were taken a while ago. The annex is pretty much done except for running some infrastructure and tying up odds and ends. It's already being used.
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Padrat is there anything you can share about what the falcon heavy infrastructure is going to look like at SLC-40?
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Wish I knew. All I've heard are rumors and then ill hear other rumors to dispel those rumors. So unfortunately I don't.
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Google maps now has imagery of Vandenberg from June 2012 posted.
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http://losaltos.patch.com/articles/tesla-motors-ceo-to-speak-about-spacex-solar-city-cutting-edge-cars
Tesla Motors CEO To Speak About SpaceX, Solar City & Cutting-Edge Cars
>
He'll also give his thoughts on the future of electric-powered autos and his vision for SpaceX, which includes a $36 billion space station on the surface of Mars.
>
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Google maps now has imagery of Vandenberg from June 2012 posted.
curious...
any ideas on cost to building the pad? Were they able to get some cheap storage tanks like they did for slc-40 (http://www.aero-news.net/images/content/aerospace/2008/SpaceX-SLC-40-O2-tank-0908a.jpg)?
jb
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any ideas on cost to building the pad? Were they able to get some cheap storage tanks like they did for slc-40 (http://www.aero-news.net/images/content/aerospace/2008/SpaceX-SLC-40-O2-tank-0908a.jpg)?
In mid-2010 press was reporting Musk said about $50M.
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http://losaltos.patch.com/articles/tesla-motors-ceo-to-speak-about-spacex-solar-city-cutting-edge-cars
Tesla Motors CEO To Speak About SpaceX, Solar City & Cutting-Edge Cars
He'll also give his thoughts on the future of electric-powered autos and his vision for SpaceX, which includes a $36 billion space station on the surface of Mars.
IIRC, in the early 90's NASA told Bush senior that it would cost $400B to put people on the surface of Mars and bring them home. Now Musk says that it will cost less than a tenth of that to establish a "space station on the surface of Mars." I would love to know how he gets that number.
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Just guessing here, but reusable BFR is instrumental. I'm looking forward to the talk as well.
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http://losaltos.patch.com/articles/tesla-motors-ceo-to-speak-about-spacex-solar-city-cutting-edge-cars
Tesla Motors CEO To Speak About SpaceX, Solar City & Cutting-Edge Cars
He'll also give his thoughts on the future of electric-powered autos and his vision for SpaceX, which includes a $36 billion space station on the surface of Mars.
IIRC, in the early 90's NASA told Bush senior that it would cost $400B to put people on the surface of Mars and bring them home. Now Musk says that it will cost less than a tenth of that to establish a "space station on the surface of Mars." I would love to know how he gets that number.
I would also love to hear where that $36 billion is going to come from.
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Can someone explain why Orion has the 'ribs' from it's orthogrid on the outside and Dragon has them on the inside?
What are the pros and cons of each?
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Can someone explain why Orion has the 'ribs' from it's orthogrid on the outside and Dragon has them on the inside?
What are the pros and cons of each?
I can't explain "why", but I'll try with the "how". Dragon's orthogrid panels are machined first, then they're bent, then welded together. Unless I'm mistaken, Orion's panels or sections are bent, welded, and then machined on a large multi-axis milling machine. It's probably a lot easier to machine the outside of the hull than the inside.
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Can someone explain why Orion has the 'ribs' from it's orthogrid on the outside and Dragon has them on the inside?
What are the pros and cons of each?
I can't explain "why", but I'll try with the "how". Dragon's orthogrid panels are machined first, then they're bent, then welded together. Unless I'm mistaken, Orion's panels or sections are bent, welded, and then machined on a large multi-axis milling machine. It's probably a lot easier to machine the outside of the hull than the inside.
SpaceX also uses stir welds its ridges into the material versus cutting the ridges out of a larger block of material, much less wasted material.
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Are you sure about that? Seems I remember reading somewhere that the Iso/orthogrid panels were milled out of a solid piece at SpaceX.
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Are you sure about that? Seems I remember reading somewhere that the Iso/orthogrid panels were milled out of a solid piece at SpaceX.
Possibly I'm confusing Dragon with Falcon 9, but Elon certainly stated that they stir weld reinforcement into panels, one of their "key technologies."
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Are you sure about that? Seems I remember reading somewhere that the Iso/orthogrid panels were milled out of a solid piece at SpaceX.
Possibly I'm confusing Dragon with Falcon 9, but Elon certainly stated that they stir weld reinforcement into panels, one of their "key technologies."
From the attached pdf file.
The first stage of the Falcon 9 is comprised of
aluminum-lithium propellant tanks, the previously
mentioned composite thrust skirt and aluminum thrust
frame, and the engines. The tanks are constructed from
an aluminum-lithium alloy that is lighter in weight than
traditional aluminum while providing improved
stiffness. A common dome is used to separate the fuel
and oxidizer tanks, minimizing mass and cost. The
tanks are produced using friction stir welding, which
creates a high-quality, repeatable weld. The tanks
employ a combination of monocoque and skin-andstringer
design and are used as primary load-bearing
structure.
Structures
• The first and second stages share a common
architecture; tooling costs are reduced and only one
welding line is required for each vehicle
• Common bulkhead design avoids need for intertank
structures
• By using a design that requires pressurization to
handle flight loads, but not ground loads, the need
for machined isogrid structures is avoided
• The composite structures for each vehicle are
manufactured on the same tooling mandrels
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Hmm, nothing in there about the Dragon, just Falcon.
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Can someone explain why Orion has the 'ribs' from it's orthogrid on the outside and Dragon has them on the inside?
What are the pros and cons of each?
I can't explain "why", but I'll try with the "how". Dragon's orthogrid panels are machined first, then they're bent, then welded together. Unless I'm mistaken, Orion's panels or sections are bent, welded, and then machined on a large multi-axis milling machine. It's probably a lot easier to machine the outside of the hull than the inside.
SpaceX also uses stir welds its ridges into the material versus cutting the ridges out of a larger block of material, much less wasted material.
if i remember correctly, can't stir weld an L joint. fastest and less wasted material is to use electric beam to print it out. I think spacex use cnc.
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Dragon is made from sections which are first milled, then formed, then welded. See the following sequence of pictures and captions; from:
http://twitter.com/SpaceX/status/104236392292429824
http://twitter.com/SpaceX/status/104237226048761856
http://twitter.com/SpaceX/status/104235681286602752
http://twitter.com/SpaceX/status/104219366802997248
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Thanks guys.
CorrodedNut's why Orions ribs are on the outside and Dragons inside seems pretty plausible. So what are the pros and cons of having the 'ribs' on the inside or outside? Maybe it doesn't really matter.
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All roads lead to Rome. Unless you use Apple Maps.
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So what are the pros and cons of having the 'ribs' on the inside or outside? Maybe it doesn't really matter.
Having them inside would imply slightly greater tensional strength and slightly less compressional strength, and on the outside would add slightly to compressional strength at slight cost to tensional. This might have some subtle difference in re-entry strength to weight, though the difference would probably be so small that other factors might dominate (just guessing). I don't know what those other factors would be. It might be something as simple as the observation that a smooth exterior allows less complex (or slightly lighter) thermal protection or an easier method of avionics cable attachments. I would guess that there is more to it, but don't know enough about spacecraft design to randomly guess any further (and may have guessed too far already).
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All roads lead to Rome. Unless you use Apple Maps.
Even then, you might find yourself on the Applian Way ... ;)
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All roads lead to Rome. Unless you use Apple Maps.
Even then, you might find yourself on the Applian Way ... ;)
nope, you stucked in an "I"land.
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The SpaceX twitter account just linked to this long Siemens ad with a SpaceX focus:
http://www.youtube.com/watch?v=U1EJinxpx4Y&feature=player_embedded
Lots of interesting shots there, specifically regarding the 5m fairing for the first VAFB launch.
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Great snag, Lars, some really interesting shots in there.
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What a great shot of the business end of the v1.0. I wonder how long ago they did the filming?
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and some missed this frame....
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Prober: Great observation!
"Looks like something from the future".
I'd be over the moon for a relevant scale bar. :D
Based on what looks like super dracos up top, in the bulge just under the heat shield, it looks like it should be able to separate if an abort is required.
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That, or it's a Falcon 9 v1.0 thrust structure and Kero tanks sans the LOX tank and Merlins.
If Elon sneezes, we speculate it is how spaceX plans to combat the common cold on Mars.
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That, or it's a Falcon 9 v1.0 thrust structure and Kero tanks sans the LOX tank and Merlins.
If Elon sneezes, we speculate it is how spaceX plans to combat the common cold on Mars.
THIS.
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Based on what looks like super dracos up top, in the bulge just under the heat shield, it looks like it should be able to separate if an abort is required.
It's not a Falcon 9 v1.1 people. Stop stating this. Engine configuration says it's F9 v1.0.
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Probably. I'm on my iPhone now, but it looked to me on first glance like a 9 engine upper stage with a weird looking "heat-shield up" dragon iteration on the top. But I could be wrong. Obviously.
It would make sense from a second stage reuse perspective (maybe) on tourist "dragon" missions. There doesn't need to be 2 heat shields for example...Windows could be protected on the other side, and there could be in-space separation and re-attachment before combined re-entry. Upper stage is also the new reusable trunk? Probably just my imagination getting away on me. If refuelable or "in-space exchangeable", could also act as a lunar crasher stage. FH might be able to get the whole works to orbit mostly or fully fueled.
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and some missed this frame....
What's so special about that frame? it is just a F9 v1.0 1st stage in orthographic (non-perspective) projection.
EDIT: Looking at it closer, it looks actually like the interstage and 2nd stage is there too. The projection just makes it look compressed.
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Few frames after, on the same monitor ....
Nothing but a v1.0 distorted from the view.
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Saw this:
http://www.geek.com/articles/geek-cetera/elon-musk-offers-boeing-spacex-batteries-for-the-787-dreamliner-20130129/
Make of it what you will...
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I think you might be right.
But it still looks like a bulge to me at the far end.
A VERY strange perspective to say the least.
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That strange perspective is not strange at all, if you have any experience with CAD and/or 3D modeling tools.
The bulge at the end might actually be the Dragon heat shield.
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That strange perspective is not strange at all, if you have any experience with CAD and/or 3D modeling tools.
As a 3D artist I concur.
The bulge at the end might actually be the Dragon heat shield.
To me it looks like the part of the upper stage that fits underneath the Dragon's solar array covers.
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does center has lower pressure while other 8 engines burning? if os does center engine has higher isp at sea level than other 8 of them?
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Was looking at the the SPX launch site from the NASA cauesway on Sunday, and it looked a lot as if there was a F9 standing out there on the pad... perhaps I'm missing something (as usual) ;)
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I think the guys said it was filmed one or two flights ago...
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Was looking at the the SPX launch site from the NASA cauesway on Sunday, and it looked a lot as if there was a F9 standing out there on the pad... perhaps I'm missing something (as usual) ;)
Just the T/E upright. Was being checked out after finishing one of the pad mods.
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Was looking at the the SPX launch site from the NASA cauesway on Sunday, and it looked a lot as if there was a F9 standing out there on the pad... perhaps I'm missing something (as usual) ;)
Just the T/E upright. Was being checked out after finishing one of the pad mods.
[/quote
What mods?
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That explains it. Thanks Padrat
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Was looking at the the SPX launch site from the NASA cauesway on Sunday, and it looked a lot as if there was a F9 standing out there on the pad... perhaps I'm missing something (as usual) ;)
Just the T/E upright. Was being checked out after finishing one of the pad mods.
[/quote
What mods?
Getting a head start on 1.1 stuff
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Was looking at the the SPX launch site from the NASA cauesway on Sunday, and it looked a lot as if there was a F9 standing out there on the pad... perhaps I'm missing something (as usual) ;)
Just the T/E upright. Was being checked out after finishing one of the pad mods.
[/quote
What mods?
Getting a head start on 1.1 stuff
Is SpaceX using a new T/E for the 1.1?
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Probably. I'm on my iPhone now, but it looked to me on first glance like a 9 engine upper stage with a weird looking "heat-shield up" dragon iteration on the top. But I could be wrong. Obviously.
This is how people started seeing pyramids on Mars, or further back, canals on Mars.
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That strange perspective is not strange at all, if you have any experience with CAD and/or 3D modeling tools.
As a 3D artist I concur.
Another one here? As another 3D artist, I concur too ;)
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This is how people started seeing pyramids on Mars, or further back, canals on Mars.
Well, hey now, that's a bit different. If you blur out a modern map of Mars, Lowell was actually pretty close on the major features (you can actually do this with Google Mars). And he did see changing features; we now know them to be dust storms, but the scientific consensus at the time was seasonal vegetation. Hoogaland sees pyramids on Mars because he's a crazy nutbag conspiracy theorist who thinks everything is a cover up. Nowhere near that same.
(And I'm totally not biased because I work at Lowell Observatory. ;) )
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Was looking at the the SPX launch site from the NASA cauesway on Sunday, and it looked a lot as if there was a F9 standing out there on the pad... perhaps I'm missing something (as usual) ;)
Just the T/E upright. Was being checked out after finishing one of the pad mods.
[/quote
What mods?
Getting a head start on 1.1 stuff
Is SpaceX using a new T/E for the 1.1?
Already being built...
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http://www.youtube.com/watch?v=J_af0ow1__E
Popular Mechanics interview with Elon Musk, taking notes now.
-Elon is hoping for 1st propulsive landing in 2013-2014, which sounds like a CRS mission that does propulsive landing.
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What's sourly sourly missing is DragonHopper. Is there any reason to try propulsive landing for the first times on real returning capsules, with or without parachutes?
So what's prevented them from pursuing low-altitude flights with SuperDracos?
There are two possibilities:
1) SuperDraco is not ready yet.
2) There was a deeper-than-expected redesign of Dragon.
Given how quickly they came up with GH, my money is on #1 being the reason.
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What's sourly sourly missing is DragonHopper. Is there any reason to try propulsive landing for the first times on real returning capsules, with or without parachutes?
So what's prevented them from pursuing low-altitude flights with SuperDracos?
There are two possibilities:
1) SuperDraco is not ready yet.
2) There was a deeper-than-expected redesign of Dragon.
Given how quickly they came up with GH, my money is on #1 being the reason.
A vtvl vehicle with gimbaling is easier and better in some ways than differential throttling. Also, kerosene is a lot less toxic than hydrazine. Also, Superdracos will be used for abort before being used for vertical landing.
Also, they'll be using first stage of Falcon 9 more than they will use Dragon, so getting that cheaper is arguably even more important for SpaceX, since they've already got Dragon splashdown recovery to work three times now.
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What's sourly sourly missing is DragonHopper. Is there any reason to try propulsive landing for the first times on real returning capsules, with or without parachutes?
So what's prevented them from pursuing low-altitude flights with SuperDracos?
There are two possibilities:
1) SuperDraco is not ready yet.
2) There was a deeper-than-expected redesign of Dragon.
Given how quickly they came up with GH, my money is on #1 being the reason.
Give them time. Right now they are working towards a pad abort test. This will likley be a bare bones dragon rider with lots of instrumentation. There is no reason they cant dragonhopper around with it afterward.
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Over on the crewed Dragon thread Lars_J posted this old pdf from2011 http://www.astronautical.org/sites/default/files/attachment/Bjelde.pdf
These pictures are from page 19, gotta love those fins :)
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What's sourly sourly missing is DragonHopper. Is there any reason to try propulsive landing for the first times on real returning capsules, with or without parachutes?
So what's prevented them from pursuing low-altitude flights with SuperDracos?
There are two possibilities:
1) SuperDraco is not ready yet.
2) There was a deeper-than-expected redesign of Dragon.
Given how quickly they came up with GH, my money is on #1 being the reason.
Dragonhopper would also require a separate experimental license, yes? And possibly a separate environmental assessment (for the hypergolics vs Grasshopper's kerolox)?
How far along was that process for Grasshopper before we heard of it?
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What's sourly sourly missing is DragonHopper. Is there any reason to try propulsive landing for the first times on real returning capsules, with or without parachutes?
So what's prevented them from pursuing low-altitude flights with SuperDracos?
There are two possibilities:
1) SuperDraco is not ready yet.
2) There was a deeper-than-expected redesign of Dragon.
Given how quickly they came up with GH, my money is on #1 being the reason.
Dragonhopper would also require a separate experimental license, yes? And possibly a separate environmental assessment (for the hypergolics vs Grasshopper's kerolox)?
How far along was that process for Grasshopper before we heard of it?
Agree with all the comments above. What I was saying is that if Elon is talking about doing propulsive landings in 2013-2014, DragonHopper should have already made an appearance, and so is likely to make one soon - or even 2014 will be tight.
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http://www.youtube.com/watch?v=J_af0ow1__E
At 12:56. "What we're going to for, call it [Dragon] v1.5, is parachutes to a land landing. I'm hoping to be able to do that next year [2013], but certainly the year after [2014]. And then level 2, maybe even level 3, because level 2 is like wings, but then level 3 would be landing with thrusters."
Elon talking about wings on a dragon?? Hasn't he recently stated he hated wings??
At 13:56. "You can lose any one of the [SuperDraco] engines and still be safe. And then we have parachutes as a backup."
Parachutes confirmed (kind of knew this already) for even being on SuperDraco landing Dragon.
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Elon talking about wings on a dragon?? Hasn't he recently stated he hated wings??
I doubt that! He was talking about level 2 being like wings, not using wings (I think.) But I'm not really sure what he meant by level 2. At this point I'm going to stop trying to read the tea leaves.
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Elon talking about wings on a dragon?? Hasn't he recently stated he hated wings??
I doubt that! He was talking about level 2 being like wings, not using wings (I think.) But I'm not really sure what he meant by level 2. At this point I'm going to stop trying to read the tea leaves.
I think he's referring to a precision landing (say, on a runway) by actively controlling the lift of Dragon using the Draco thrusters (à la Mars Science Laboratory reentry) and touching down with parachutes. That would be "like wings" because one of the advantages that people put forward about winged spacecraft is that they can land on a runway.
He's talked many times before about active reentry and precision landing of a capsule spacecraft.
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I'm pretty sure he was talking about having some sort of retractable flaps to control where the craft will land. The superdracos will just make sub kilometer adjustment to land on the pad.
That makes sense to test, even before having thrusted landing. That is why he mentioned it before "V3".
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Elon talking about wings on a dragon?? Hasn't he recently stated he hated wings??
At 13:56. "You can lose any one of the [SuperDraco] engines and still be safe. And then we have parachutes as a backup."
no, no wings...
"v2 is LIKE having wings", but then we move on to level 3... you don't literally introduce wings for an interim version...
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"v2 is LIKE having wings", but then we move on to level 3... you don't literally introduce wings for an interim version...
my WAG is I would think that the next version has more of a lift to the capsule so it has better ability to adjust flight path..not that it seems to be an issue with V1
jb
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My guess (to explore the difference between v1.5 and v2.0) :
- v1 is parachute splashdown
- v1.5 still uses parachutes the same way but activates the thrusters to make the landing soft, so potentially on ground, but no improvement in precision
- v2 uses thrusters first to steer the Dragon to a designated location and uses parachutes late for assured braking, precision between 100 and 500 metres
- v3 is all thrusters, precision of 10 metres
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My guess is he meant dragon will skip "level 2" (because that's, like, wings) and go straight to "level 3".
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My guess is he meant dragon will skip "level 2" (because that's, like, wings) and go straight to "level 3".
That was my take too.
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Elon talking about wings on a dragon?? Hasn't he recently stated he hated wings??
At 13:56. "You can lose any one of the [SuperDraco] engines and still be safe. And then we have parachutes as a backup."
no, no wings...
"v2 is LIKE having wings", but then we move on to level 3... you don't literally introduce wings for an interim version...
paraglider
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http://www.youtube.com/watch?v=J_af0ow1__E
At 12:56. "What we're going to for, call it [Dragon] v1.5, is parachutes to a land landing. I'm hoping to be able to do that next year [2013], but certainly the year after [2014]. And then level 2, maybe even level 3, because level 2 is like wings, but then level 3 would be landing with thrusters."
Elon talking about wings on a dragon?? Hasn't he recently stated he hated wings??
At 13:56. "You can lose any one of the [SuperDraco] engines and still be safe. And then we have parachutes as a backup."
Parachutes confirmed (kind of knew this already) for even being on SuperDraco landing Dragon.
Thanks for posting this. :)
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http://shitelonsays.com/transcript/elon-musk-panel-bta-2012-2013-01-28
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I'm pretty sure he was talking about having some sort of retractable flaps to control where the craft will land. The superdracos will just make sub kilometer adjustment to land on the pad.
That makes sense to test, even before having thrusted landing. That is why he mentioned it before "V3".
That would make more sense. The flaps are probably needed for version 3 anyways.
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I'm pretty sure he was talking about having some sort of retractable flaps to control where the craft will land. The superdracos will just make sub kilometer adjustment to land on the pad.
That makes sense to test, even before having thrusted landing. That is why he mentioned it before "V3".
That would make more sense. The flaps are probably needed for version 3 anyways.
No. He was referring to spacecraft landing technology in general for the levels, not specifically for Dragon.
Level 1: parachute + water splashdown (Apollo, current Dragon)
Level 1.5: parachute + retro rocket or airbag landing (Soyuz, CT-100, Blue origin and next Dragon)
Level 2: Wings (Shuttle, X-37, Dream chaser)
Level 3: propulsion landing + parachute backup (future Dragon)
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I'm pretty sure he was talking about having some sort of retractable flaps to control where the craft will land. The superdracos will just make sub kilometer adjustment to land on the pad.
That makes sense to test, even before having thrusted landing. That is why he mentioned it before "V3".
That would make more sense. The flaps are probably needed for version 3 anyways.
No. He was referring to spacecraft landing technology in general for the levels, not specifically for Dragon.
Level 1: parachute + water splashdown (Apollo, current Dragon)
Level 1.5: parachute + retro rocket or airbag landing (Soyuz, CT-100, Blue origin and next Dragon)
Level 2: Wings (Shuttle, X-37, Dream chaser)
Level 3: propulsion landing + parachute backup (future Dragon)
Agreed.
It should be noted that Dragon can already get very close using just Dragon's own guidance capabilities it has now. What makes the big dispersion on landing is the parachute and being dragged around by the wind, etc.
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http://shitelonsays.com/transcript/elon-musk-panel-bta-2012-2013-01-28
I like the name of the website. :) Here is what Elon actually said:
Version 1 of Dragon is pretty basic really. I'd classify it as, kinda, level one reentry and landing, which is parachutes to a water landing. It's fairly straightforward and fairly reliable but what we're going to for, call it, version 1.5 is we're going to go parachutes to a land landing. I'm hoping we'll be able to do that next year, but certainly the year or there after. Then, level 2, or maybe even level 3 - maybe level 2 is like wings - but then level 3 would be landing with thrusters. Another advantage of having the escape thrusters built into the escape wall of the Dragon is that, when you come back, you can use some of them to land. So, they're really high precision and they're redundant thrusters - you have eight - and well, if you lost the right four you could lose four - you could lose at least one - they're in pairs, so. We've gone back and forth on how we can make this better, but there's so many constraints in the system, but this is pretty good. You can lose any one of the engines and still be safe, and then we have parachutes as a backup on top of that, so - and the parachutes are redundant. So, there should be - I can't think of a safer way to do it, honestly, than to have redundant thrusters and redundant parachutes for landing. In a best case scenario you can be quite reusable because you can land propulsively - just like they landed on the Moon - and that sets you up for reuse quite well.
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I'm pretty sure he was talking about having some sort of retractable flaps to control where the craft will land. The superdracos will just make sub kilometer adjustment to land on the pad.
That makes sense to test, even before having thrusted landing. That is why he mentioned it before "V3".
That would make more sense. The flaps are probably needed for version 3 anyways.
No. He was referring to spacecraft landing technology in general for the levels, not specifically for Dragon.
Level 1: parachute + water splashdown (Apollo, current Dragon)
Level 1.5: parachute + retro rocket or airbag landing (Soyuz, CT-100, Blue origin and next Dragon)
Level 2: Wings (Shuttle, X-37, Dream chaser)
Level 3: propulsion landing + parachute backup (future Dragon)
Agreed.
It should be noted that Dragon can already get very close using just Dragon's own guidance capabilities it has now. What makes the big dispersion on landing is the parachute and being dragged around by the wind, etc.
FWIW, now that I have read the transcript, I have changed my mind and I agree with both of you. He was trying to make the point that propulsion landing is better (i.e., it is at a higher level) than having wings.
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No. He was referring to spacecraft landing technology in general for the levels, not specifically for Dragon.
Level 1: parachute + water splashdown (Apollo, current Dragon)
Level 1.5: parachute + retro rocket or airbag landing (Soyuz, CT-100, Blue origin and next Dragon)
Level 2: Wings (Shuttle, X-37, Dream chaser)
Level 3: propulsion landing + parachute backup (future Dragon)
Agreed.
It should be noted that Dragon can already get very close using just Dragon's own guidance capabilities it has now. What makes the big dispersion on landing is the parachute and being dragged around by the wind, etc.
FWIW, now that I have read the transcript, I have changed my mind and I agree with both of you. He was trying to make the point that propulsion landing is better (i.e., it is at a higher level) than having wings.
Yes, kudos to king1999, I think that is the most believeable interpretation of the conversation. Elon's intention is for Dragon to go from level 1.5 straight to level 3 class re-entry and landing.
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Ah, the joys of trying to understand http://shitelonsays.com ...
Less talk, more rock...ets, Elon.
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Ah, the joys of trying to understand http://shitelonsays.com ...
Less talk, more rock...ets, Elon.
Pity the historians.
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The image is also helpful:
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The image is also helpful:
That image should be posted EVERY time someone is trying to glean information from interviews and random tweets of http://shitelonsays.com
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Why not parafoils?
They allow gliding landings without heavy wings.
Just need a couple wheels.
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Maybe electro-mechanically operated variable-drag surfaces on the upper part of the Super-draco fairings?
I remember reading once that the internal weight distribution in a ballistic capsule creates a small amount of lift. So, you have the option of a controllable near-free-fall, steering the capsule to a steeper or shallower arc by varying its drag before you reach the terminal phase when the engines cut in.
Aerospace amateur here; is that even possible?
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Maybe electro-mechanically operated variable-drag surfaces on the upper part of the Super-draco fairings?
I remember reading once that the internal weight distribution in a ballistic capsule creates a small amount of lift. So, you have the option of a controllable near-free-fall, steering the capsule to a steeper or shallower arc by varying its drag before you reach the terminal phase when the engines cut in.
Aerospace amateur here; is that even possible?
Of course. As long as the center of pressure and center of mass aren't right at the same point, you can steer by moving them with respect to each other.
But again, this is a silly discussion.
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Pic of rock band Muse visiting SpaceX factory. It was Muse's music that was originally used for the SpaceX reuse system video.
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Why not parafoils?
They allow gliding landings without heavy wings.
Just need a couple wheels.
I've never seen parafoils mentioned by SpaceX. Since the SuperDracos are a given for launch escape, then using them for landing (with or without parachute assistance) makes more sense to me.
I would put parafoils in the "unlikely" category.
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Continued from advanced concepts, OT there, more suitable here, I hope.
Orbcomm's birds are very lightweight. If you've got enough satellites, your deployment mechanism may weigh nearly as much as the total mass of all the deployed satellites.
..or may not, as in gen1. But this is getting OT so I won't comment this more in here.
(http://upload.wikimedia.org/wikipedia/commons/thumb/2/2c/ORBCOMM_integrated.jpg/640px-ORBCOMM_integrated.jpg)
How much did the deployment mechanism weigh?
At maximum Pegasus' capacity (listed as 443kg in wiki) to intended orbit minus 8 x 42kg, so 107kg or less apparently.
Are you going to do multiple burns because of all the different payloads? That takes propellant, which comes from your payload.
Unknown, mut unlikely any of great magnitude. All SCs in the stack end up on same orbital plane, no?
Also, you have the payload integration which may be more complicated for a whole bunch of birds like that.
Yes it may, or may not. Depends on how deployment happens and responsibility is shared. Does Orbcomm deliver a ready stack of SCs, effectively singular SC and ask it to be deployed to intended orbit, and from there it's Orbcomm's responsibility to split it and maneuver individual SCs to their slots. Or do they deliver multiple SCs and it's launch service provider's task to stack them and deploy each to final slot? I do not know.
Also, do you know what ORBCOMM paid per kg to LEO for their first gen constellation? It was launched on Pegasus, which had a launch cost in 1994 of $11 million (~$17 in today's currency). For the ~40kg ORBCOMM-1 birds (with 8 launched at once), that works out to $35,000/kg to LEO in 1994, or about $53,000/kg to LEO in today's money. So yeah, I'd say $16,000/kg to LEO is a significant improvement.
Apple, orange. Comparing possibly the most expensive LV with minisat capacity to anything else yields 'impressive' price reductions. Falcon-1 would have been in comparable category with Pegasus, but Elon in his infinite wisdow saw fit to tell future minisat customers to either get stuffed, buy Falcon-9 or hope for an opportunity to piggyback.
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It /was/ wisdom for SpaceX to basically abandon Falcon 1/1e.
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I agree, wise for SpaceX. And good for Orbital! ;) Only the minisat customers got short end of the stick. In Orbcomm's case amount of SCs saved. As long as no more asplosions ;D
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Very simple really.
With COTS and with the success of F9, operating the F1 was no longer on the path between here and Mars.
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If Falcon 9 really does have good performance and is capable of a lot of restarts, it may not end up being such a bad deal after all. Falcon 9 is much cheaper per kg to LEO, and flying as a secondary isn't so bad. And Falcon 1/1e couldn't really go beyond LEO anyway.
Spaceflight Services ( http://spaceflightservices.com/pricing-plans/ ), which helps arrange secondaries for Falcon 9 (and other) launches isn't such a bad deal, actually. Not terribly good if you need to launch a big constellation of microsats weighing hundreds of kilograms, but if you need just a few weighing less, it looks like a pretty good deal. And if you need a ride to GSO or GEO, you couldn't really use Falcon 1/1e anyway.
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Unless they are sold out when you need or want a ride up or don't want to share a ride.
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http://www.youtube.com/v/AHHwXUm3iIg?version=3&hl=en_US&rel=0
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Is that on Trent's website, yet?
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http://shitelonsays.com/transcript/computer-history-museum-presents-an-evening-with-elon-musk-2013-01-24
Transcribed from audio. Thanks for the video link.
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http://shitelonsays.com/transcript/computer-history-museum-presents-an-evening-with-elon-musk-2013-01-24
Transcribed from audio. Thanks for the video link.
Just watched the video. Turns out the audio link wasn't complete as compared to the video. Editing was done. Here are a few times I found that have parts of the interview that were in the video, but not in the audio.
0:37:50 - 0:39:20
0:47:20 - 1:01:50
1:03:18 - 1:04:57
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http://shitelonsays.com/transcript/computer-history-museum-presents-an-evening-with-elon-musk-2013-01-24
Transcribed from audio. Thanks for the video link.
Just watched the video. Turns out the audio link wasn't complete as compared to the video. Editing was done. Here are a few times I found that have parts of the interview that were in the video, but not in the audio.
0:37:50 - 0:39:20
0:47:20 - 1:01:50
1:03:18 - 1:04:57
Moan. Thanks, I'll look at it tomorrow.
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From Jeff Foust's Twitter
Tim Hughes, SpaceX: when I joined the company I was employee #81. Company just crossed 3,000-employee mark. #faacstc
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From Jeff Foust's Twitter
Tim Hughes, SpaceX: when I joined the company I was employee #81. Company just crossed 3,000-employee mark. #faacstc
And this is seen as a feature, not a bug? ;)
(At $100K per employee, or about 2.5x below the cost of a normal "OldSpace" man-year, employee overhead contributes $25M of the cost of a launch...assuming twelve launches per year and no growth of staff. If SpaceX achieves 3 or 4 flights this year, the labor overhead cost per flight alone will be between $100M and $75M, slightly more than the average revenue from those flights not counting any other expenses.)
Can you say "ULA-lite"?
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From Jeff Foust's Twitter
Tim Hughes, SpaceX: when I joined the company I was employee #81. Company just crossed 3,000-employee mark. #faacstc
And this is seen as a feature, not a bug? ;)
(At $100K per employee, or about 2.5x below the cost of a normal "OldSpace" man-year, employee overhead contributes $25M of the cost of a launch...assuming twelve launches per year and no growth of staff. If SpaceX achieves 3 or 4 flights this year, the labor overhead cost per flight alone will be between $100M and $75M, slightly more than the average revenue from those flights not counting any other expenses.)
Can you say "ULA-lite"?
Of course, since they're so vertically integrated, almost all the cost of the rocket is man-hours anyway.
Also, don't forget that Dragon (cargo and crew) must consume a lot of their manpower. So does Falcon Heavy. They get maybe half or more of their money from Dragon-related work. And, in fact, some fraction are working on future projects like Grasshopper (though I bet that number is much, much smaller than those working on Dragon), and probably some are devoted to new engine work. If they were simply launching Falcon 9, they could be much smaller. And I doubt they're taking any profit out of the company, likely just investing it back into R&D efforts and new product lines (i.e. Grasshopper, Falcon Heavy, Dragon, probably back-burner new engine tech, etc).
But they do need to increase flight rate a lot.
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Can you say "ULA-lite"?
Made a prediction in the rational outlook thread:
By 2019 SpaceX has grown so large that it's indistinguishable from "oldSpace".
Unsure if that just got proven right or wrong. Technically 'now' is 'by 2019' but sort of implied that it would still take some time!?
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It seems that both ULA and Orbital are around 3900 employees.
Now, they aren't as vertically integrated as SpaceX, but both companies do launch more often.
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From Jeff Foust's Twitter...I was employee #81. Company just crossed 3,000-employee mark
And this is seen as a feature, not a bug?
I strongly suspect that they handed out employee number 3000. Not that they have 3000 employees. They've been around for 13 years. People come and go. I would guess 2000 current employees maybe. ...but I might be wrong...
Whether 2000 or 3000, you make a reasonable point (assuming flight rate stays EELVish). If they can get incremental cost per flight significantly down, like with a reusable first stage and capsule, (and with higher manufacture rate of expendible upper stages) then tourist-driven flight rate might go up a lot. Until then, there's still a big launch manifest and cargo/crew money, as well as a motivated billionaire (with billionaire friends) at the helm. If all else fails, they can charge more until fully reusable, or IPO as a last resort.
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What I with I knew was how many of the 3000 are doing development work and how many are ops/sales/etc. There will be some overlap (e.g. in testing) but still, it would be paint a more useful picture for comparison.
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As of October, SpaceX press releases said they had "more than 1,800" employees; now it's "more than 2,000." No way they're actually at 3000. I agree with go4mars.
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From Jeff Foust's Twitter...I was employee #81. Company just crossed 3,000-employee mark
And this is seen as a feature, not a bug?
I strongly suspect that they handed out employee number 3000. Not that they have 3000 employees. They've been around for 13 years. People come and go. I would guess 2000 current employees maybe. ...but I might be wrong...
Whether 2000 or 3000, you make a reasonable point (assuming flight rate stays EELVish). If they can get incremental cost per flight significantly down, like with a reusable first stage and capsule, (and with higher manufacture rate of expendible upper stages) then tourist-driven flight rate might go up a lot. Until then, there's still a big launch manifest and cargo/crew money, as well as a motivated billionaire (with billionaire friends) at the helm. If all else fails, they can charge more until fully reusable, or IPO as a last resort.
Doubt thats the case. Last year (last academic year so fall 2011) they stated they were over 2000 employees, pretty sure they just broke 3000 actual employees which would make sense as people who graduated at end of 2012 probably are finishing moving into working around now.
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Let's say the payroll yearly cost is $300M. 2 Dragon flights this year is revenue of $260M. The DragonRider contract milestones will pull in about half of the CCiDev contract value or ~$220M, and at least 2 additional commercial flights another $108M. So revenue is $588M to payroll of $300M.
So whether it is 2000 or 3000 employees, I think SpaceX has the revenue to cover it.
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The 3000 employee data was also in link just posted on Falcon 1.1 thread
http://www.newspacewatch.com/articles/faa-conf-wed-afternoon-pt-2-notes.html (http://www.newspacewatch.com/articles/faa-conf-wed-afternoon-pt-2-notes.html)
FAA Conf. Wed Afternoon, pt. 2 - notes
...
Tim Hughes (VP, SpaceX)
Shows video of SpaceX highlights
Started when company less than 100. Just crossed 3000.
PS but is the OT sheriff OK with this...
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By 2019 SpaceX has grown so large that it's indistinguishable from "oldSpace".
Unsure if that just got proven right or wrong. Technically 'now' is 'by 2019' but sort of implied that it would still take some time!?
That assumes that employee count is the only thing that distinguishes "oldSpace" from "newSpace".
It is a factor, for sure, but given its vertical integration you would have to include PwR and other sub-contractors to ULA's count to get a more comparable employee count.
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Not sure where to post.
Tommorow there will be AMA with SpaceX software engineers at Reddit
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Not sure where to post.
Tommorow there will be AMA with SpaceX software engineers at Reddit
That sounds like a live event, see if Chris will start a new thread for it?
someone did create one.
http://forum.nasaspaceflight.com/index.php?topic=31050.0
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Let's say the payroll yearly cost is $300M. 2 Dragon flights this year is revenue of $260M. The DragonRider contract milestones will pull in about half of the CCiDev contract value or ~$220M, and at least 2 additional commercial flights another $108M. So revenue is $588M to payroll of $300M.
So whether it is 2000 or 3000 employees, I think SpaceX has the revenue to cover it.
Note I was assuming that their "man-year" is only $100K. That's a very generous assumption. If it is closer to $200K like everyone else, then they just break even...only on labor costs.
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Let's say the payroll yearly cost is $300M. 2 Dragon flights this year is revenue of $260M. The DragonRider contract milestones will pull in about half of the CCiDev contract value or ~$220M, and at least 2 additional commercial flights another $108M. So revenue is $588M to payroll of $300M.
So whether it is 2000 or 3000 employees, I think SpaceX has the revenue to cover it.
Note I was assuming that their "man-year" is only $100K. That's a very generous assumption. If it is closer to $200K like everyone else, then they just break even...only on labor costs.
Again, you're excluding Dragon, which is probably just as much of the company as Falcon 9 is. They get paid a lot more for Dragon missions.
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NASA MEDIA ADVISORY: M13-028
NASA ADMINISTRATOR, INTERIOR SECRETARY (to) ATTEND LANDSAT LAUNCH
WASHINGTON -- NASA Administrator Charles Bolden and Interior Secretary Ken Salazar will attend the launch of the Landsat Data Continuity Mission (LDCM) from Vandenberg Air Force Base in California on Monday, Feb. 11. The launch is scheduled for 10:02 a.m. PST.
[snip]
Following the post-launch news conference, Bolden will visit the SpaceX launch pad at 1:30 p.m. The launch pad, which is being built at Space Launch Complex-4, will support the SpaceX Falcon 9 and Falcon Heavy rockets. In 2015, a Falcon 9 rocket will launch the Jason-3 sea surface monitoring mission from Vandenberg.
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Let's say the payroll yearly cost is $300M. 2 Dragon flights this year is revenue of $260M. The DragonRider contract milestones will pull in about half of the CCiDev contract value or ~$220M, and at least 2 additional commercial flights another $108M. So revenue is $588M to payroll of $300M.
So whether it is 2000 or 3000 employees, I think SpaceX has the revenue to cover it.
Note I was assuming that their "man-year" is only $100K. That's a very generous assumption. If it is closer to $200K like everyone else, then they just break even...only on labor costs.
Again, you're excluding Dragon, which is probably just as much of the company as Falcon 9 is. They get paid a lot more for Dragon missions.
I'm only talking about the total labor costs of the enterprise. It doesn't matter what the people are doing; they still have to be paid. And oldAtlas_Eguy noted that they get perhaps $260M in CRS revenue this year, so that's not being ignored.
The message is the labor cost are huge and growing. Low-cost space transportation need a reduction in the standing army, no matter what they are doing. SpaceX isn't doing that.
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Low-cost space transportation needs some combination of reduction in standing army and increase in demand/launch-rate.
ULA is not building a capsule or doing ISS cargo.
And I bet if SpaceX were to focus just on Falcon 9, they could cut their workforce in perhaps a third or less. They wouldn't need Grasshopper, they wouldn't need Falcon Heavy, they wouldn't need further rocket engine development, they wouldn't need solar arrays or capsules or reentry processing or PICA-X or anything like that. They would be much lighter weight.
I basically agree with you, I just think you're slightly over-stating your point by implying that people doing Dragon should count in Falcon 9's overhead when Dragon is a very large revenue stream by itself.
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I'm only talking about the total labor costs of the enterprise. It doesn't matter what the people are doing; they still have to be paid. And oldAtlas_Eguy noted that they get perhaps $260M in CRS revenue this year, so that's not being ignored.
The message is the labor cost are huge and growing. Low-cost space transportation need a reduction in the standing army, no matter what they are doing. SpaceX isn't doing that.
You're both right. SpaceX is doing development and operations with labor costs that should (and are) putting everyone else to shame, and also SpaceX does not have enough revenue to keep up with all it is doing indefinitely, so needs to be careful with respect to cash flow.
The reassuring thing about this is that Elon went through a serious cash-crunch at Tesla, and could have lost the entire company there. Since Elon is clearly a learning system, I am sure he's keeping an eye on this so he doesn't end up in the same predicament.
I think he's looking at the capital he has at hand, at his launch manifest, and at his expenses, and somewhere has calculated that as long as he doesn't lose customers, he can afford to be late by X and still survive.
If his goal was to beat ULA at its own game, then yes, by all means, he should drop everything else and ops ops ops.
But his goal is further out, and as long as he thinks SpaceX is not getting into a cash crunch, he'll keep the pedal to the metal on development.
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It seems that both ULA and Orbital are around 3900 employees.
Now, they aren't as vertically integrated as SpaceX, but both companies do launch more often.
At the moment.
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From Jeff Foust's Twitter...I was employee #81. Company just crossed 3,000-employee mark
And this is seen as a feature, not a bug?
I strongly suspect that they handed out employee number 3000. Not that they have 3000 employees. They've been around for 13 years. People come and go. I would guess 2000 current employees maybe. ...but I might be wrong...
Whether 2000 or 3000, you make a reasonable point (assuming flight rate stays EELVish). If they can get incremental cost per flight significantly down, like with a reusable first stage and capsule, (and with higher manufacture rate of expendible upper stages) then tourist-driven flight rate might go up a lot. Until then, there's still a big launch manifest and cargo/crew money, as well as a motivated billionaire (with billionaire friends) at the helm. If all else fails, they can charge more until fully reusable, or IPO as a last resort.
Doubt thats the case. Last year (last academic year so fall 2011) they stated they were over 2000 employees, pretty sure they just broke 3000 actual employees which would make sense as people who graduated at end of 2012 probably are finishing moving into working around now.
Indeed, SpaceX employee turnover is supposed to be quite high compared the the rest of the industry. I'd expect that by the time they had even 2k simultaneous employees, they would have had at least 2k past employees that no longer work there. So the 3k number must be current employees.
Side note: turnover is high because pay is standard for the industry but demanded work hours are double for the industry. They are riding a coolness factor to let them get away with this, but it does cause high turnover.
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Let's say the payroll yearly cost is $300M. 2 Dragon flights this year is revenue of $260M. The DragonRider contract milestones will pull in about half of the CCiDev contract value or ~$220M, and at least 2 additional commercial flights another $108M. So revenue is $588M to payroll of $300M.
So whether it is 2000 or 3000 employees, I think SpaceX has the revenue to cover it.
Note I was assuming that their "man-year" is only $100K. That's a very generous assumption. If it is closer to $200K like everyone else, then they just break even...only on labor costs.
I know for new engineers they are not very competitive. I had graduating aerospace engineering friends who weren't interested in SpaceX at all because the 8am to 8pm workdays and the "low pay" compared to other companies. Apparently it was barely enough to pay living expenses and student loan payments.
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The message is the labor cost are huge and growing. Low-cost space transportation need a reduction in the standing army, no matter what they are doing. SpaceX isn't doing that.
I don't think we know that for sure.
In another thread, Padrat reported that they use very few people in pad operations compared to his previous (shuttle) experience. Dunno how they compare to ULA, of course, or any of the others.
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NASA MEDIA ADVISORY: M13-028
NASA ADMINISTRATOR, INTERIOR SECRETARY (to) ATTEND LANDSAT LAUNCH
WASHINGTON -- NASA Administrator Charles Bolden and Interior Secretary Ken Salazar will attend the launch of the Landsat Data Continuity Mission (LDCM) from Vandenberg Air Force Base in California on Monday, Feb. 11. The launch is scheduled for 10:02 a.m. PST.
[snip]
Following the post-launch news conference, Bolden will visit the SpaceX launch pad at 1:30 p.m. The launch pad, which is being built at Space Launch Complex-4, will support the SpaceX Falcon 9 and Falcon Heavy rockets. In 2015, a Falcon 9 rocket will launch the Jason-3 sea surface monitoring mission from Vandenberg.
what a way to ruin a launch have Bolden make a visit. So goes my plans.
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From Jeff Foust's Twitter...I was employee #81. Company just crossed 3,000-employee mark
And this is seen as a feature, not a bug?
I strongly suspect that they handed out employee number 3000. Not that they have 3000 employees. They've been around for 13 years. People come and go. I would guess 2000 current employees maybe. ...but I might be wrong...
Whether 2000 or 3000, you make a reasonable point (assuming flight rate stays EELVish). If they can get incremental cost per flight significantly down, like with a reusable first stage and capsule, (and with higher manufacture rate of expendible upper stages) then tourist-driven flight rate might go up a lot. Until then, there's still a big launch manifest and cargo/crew money, as well as a motivated billionaire (with billionaire friends) at the helm. If all else fails, they can charge more until fully reusable, or IPO as a last resort.
Doubt thats the case. Last year (last academic year so fall 2011) they stated they were over 2000 employees, pretty sure they just broke 3000 actual employees which would make sense as people who graduated at end of 2012 probably are finishing moving into working around now.
Indeed, SpaceX employee turnover is supposed to be quite high compared the the rest of the industry. I'd expect that by the time they had even 2k simultaneous employees, they would have had at least 2k past employees that no longer work there. So the 3k number must be current employees.
Side note: turnover is high because pay is standard for the industry but demanded work hours are double for the industry. They are riding a coolness factor to let them get away with this, but it does cause high turnover.
Perhaps but I'd also say that a factor is that they run a meritorious company. In other words, they expect their staff at every level to perform. Many wouldn't and either would recognise that and leave of their own volition or alternatively be asked to leave.
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Many wouldn't and either would recognise that and leave of their own volition or alternatively be asked to leave.
Burnout is the most reason for leaving
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The message is the labor cost are huge and growing. Low-cost space transportation need a reduction in the standing army, no matter what they are doing. SpaceX isn't doing that.
One thing to keep in mind is that the overwelming majority of the "standing army", as you call it, is in Hawthorne working on pumping out rockets. If you are going to put out enough rockets to meet the flight rates that are being planned for, and in as safe a manner as possible, it's going to take ALOT of people...
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NASA MEDIA ADVISORY: M13-028
NASA ADMINISTRATOR, INTERIOR SECRETARY (to) ATTEND LANDSAT LAUNCH
WASHINGTON -- NASA Administrator Charles Bolden and Interior Secretary Ken Salazar will attend the launch of the Landsat Data Continuity Mission (LDCM) from Vandenberg Air Force Base in California on Monday, Feb. 11. The launch is scheduled for 10:02 a.m. PST.
[snip]
Following the post-launch news conference, Bolden will visit the SpaceX launch pad at 1:30 p.m. The launch pad, which is being built at Space Launch Complex-4, will support the SpaceX Falcon 9 and Falcon Heavy rockets. In 2015, a Falcon 9 rocket will launch the Jason-3 sea surface monitoring mission from Vandenberg.
what a way to ruin a launch have Bolden make a visit. So goes my plans.
I think it's a good thing, because it brings up the chance that they might release pictures of the pad.
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Many wouldn't and either would recognise that and leave of their own volition or alternatively be asked to leave.
Burnout is the most reason for leaving
.. but what a way to go.
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Not sure if people have seen these pictures before, but there are a number of good ones of the solar array fairing installation on the KSC media gallery.
http://mediaarchive.ksc.nasa.gov/search.cfm
Search for SpaceX.
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I know for new engineers they are not very competitive. I had graduating aerospace engineering friends who weren't interested in SpaceX at all because the 8am to 8pm workdays and the "low pay" compared to other companies. Apparently it was barely enough to pay living expenses and student loan payments.
Unsure how it works in the US, but in Portugal freshly graduate engineers are underpaid and expected to work more hours. And there are some things money can't buy...
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Many wouldn't and either would recognise that and leave of their own volition or alternatively be asked to leave.
Burnout is the most reason for leaving
.. but what a way to go.
BTDT and it isn't fun for more than a couple of years. Any more and you realize that you missed out on a portion of your life
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Many wouldn't and either would recognise that and leave of their own volition or alternatively be asked to leave.
Burnout is the most reason for leaving
.. but what a way to go.
“My candle burns at both ends; It will not last the night; But ah, my foes, and oh, my friends It gives a lovely light!" --Edna St Vincent Millay
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The message is the labor cost are huge and growing. Low-cost space transportation need a reduction in the standing army, no matter what they are doing. SpaceX isn't doing that.
One thing to keep in mind is that the overwelming majority of the "standing army", as you call it, is in Hawthorne working on pumping out rockets. If you are going to put out enough rockets to meet the flight rates that are being planned for, and in as safe a manner as possible, it's going to take ALOT of people...
That's the funny thing. We hear they are building and testing lots of engines and have seen some Dragon cargo capsules in various stages of construction. But what is happening with all of the pieces that are getting built ? How big is the warehouse, since these components certainly aren't going to space ?
Given the current launch rate, why are they testing Merlin engines on a daily basis in Texas ?
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Given the current launch rate, why are they testing Merlin engines on a daily basis in Texas ?
Maybe working on ways to reduce engine weight? I know Formula 1 teams spend a lot of effort to save some gram per week on the cars. The season starts but they have new engine/car parts every week. One example is picking some structural element and redesigning it so it retains the same characteristics while weighting less.
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They are shooting for a high launch rate, and you can't wait to do the acceptance testing until after you launch! You need to have a long period of high testing frequency and high production capacity before you can hope to have a high launch rate. Almost tautological.
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They are shooting for a high launch rate, and you can't wait to do the acceptance testing until after you launch! You need to have a long period of high testing frequency and high production capacity before you can hope to have a high launch rate. Almost tautological.
Right. Build it, test it, put it in storage as finished goods. Once the assembly has completed acceptance testing, you move on to the next one. Now, how many days / test firings does it take for a single engine ?
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You need to have a long period of high testing frequency and high production capacity before you can hope to have a high launch rate.
And it might help with the ejecting panels issue too!
*ducks*
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BTDT and it isn't fun for more than a couple of years. Any more and you realize that you missed out on a portion of your life.
I think Jim just outed himself as a "work to live" kind of guy.
May I recommend: http://www.imdb.com/title/tt1772925/
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Many wouldn't and either would recognise that and leave of their own volition or alternatively be asked to leave.
Burnout is the most reason for leaving
.. but what a way to go.
BTDT and it isn't fun for more than a couple of years. Any more and you realize that you missed out on a portion of your life
I don't know how it is at SpaceX. But a lot of organizations expect you to work long hours at the beginning. But as you become more experienced, you are less and less required to put in long hours (unless there is an emergency) given that you compensate through your experience.
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Given the current launch rate, why are they testing Merlin engines on a daily basis in Texas ?
Maybe working on ways to reduce engine weight? I know Formula 1 teams spend a lot of effort to save some gram per week on the cars. The season starts but they have new engine/car parts every week. One example is picking some structural element and redesigning it so it retains the same characteristics while weighting less.
No, what you suggest is almost 100% incompatible with SpaceX's philosophy, which is to optimize for cost and not performance.
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Given the current launch rate, why are they testing Merlin engines on a daily basis in Texas ?
Maybe working on ways to reduce engine weight? I know Formula 1 teams spend a lot of effort to save some gram per week on the cars. The season starts but they have new engine/car parts every week. One example is picking some structural element and redesigning it so it retains the same characteristics while weighting less.
No, what you suggest is almost 100% incompatible with SpaceX's philosophy, which is to optimize for cost and not performance.
Not really. Merlin 1D is the best engine in terms of thrust/weight ratio. It is a requirement, otherwise having 9 engines would reduce performance considerably. Their 9 engines concept does not work so well with heavy engines.
And they did reduce weight from Merlin 1C to 1D, so that backs my suggestion.
Also you can optimize cost while searching for weight reduction. Redesigning a structure can lead to a simpler piece or less pieces.
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Not really. Merlin 1D is the best engine in terms of thrust/weight ratio. It is a requirement, otherwise having 9 engines would reduce performance considerably. Their 9 engines concept does not work so well with heavy engines.
You realize the point you made is irrelevant right? 100 engines or 1 engine, thrust to weight ratio is a _ratio_. Meaning 1 engine with the same thrust/weight ratio of a Merlin 1D but 9 times the thrust will have exactly the same weight as 9 Merlin 1Ds. Increasing thrust to weight is no more a requirement here than for any other rocket. So your argument that having 9 engines makes thrust/weight ratio more important is invalid.
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Not really. Merlin 1D is the best engine in terms of thrust/weight ratio. It is a requirement, otherwise having 9 engines would reduce performance considerably. Their 9 engines concept does not work so well with heavy engines.
You realize the point you made is irrelevant right? 100 engines or 1 engine, thrust to weight ratio is a _ratio_. Meaning 1 engine with the same thrust/weight ratio of a Merlin 1D but 9 times the thrust will have exactly the same weight as 9 Merlin 1Ds. Increasing thrust to weight is no more a requirement here than for any other rocket. So your argument that having 9 engines makes thrust/weight ratio more important is invalid.
Only if first stage weight scales linearly with engine count. There likely are secondary effects that make the thrust structure an engine piping support structure weight scale non-linearly with engine count.
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Given the current launch rate, why are they testing Merlin engines on a daily basis in Texas ?
Maybe working on ways to reduce engine weight? I know Formula 1 teams spend a lot of effort to save some gram per week on the cars. The season starts but they have new engine/car parts every week. One example is picking some structural element and redesigning it so it retains the same characteristics while weighting less.
No, what you suggest is almost 100% incompatible with SpaceX's philosophy, which is to optimize for cost and not performance.
Not really. Merlin 1D is the best engine in terms of thrust/weight ratio. It is a requirement, otherwise having 9 engines would reduce performance considerably. Their 9 engines concept does not work so well with heavy engines.
And they did reduce weight from Merlin 1C to 1D, so that backs my suggestion.
Also you can optimize cost while searching for weight reduction. Redesigning a structure can lead to a simpler piece or less pieces.
Redesigning again and again and never settling and always having a new version in the pipeline with just a few more tweaks here and there may be a recipe for reduced cost in a low flight and manufacturing rate operation, but SpaceX wants to mass produce to reduce costs, and endless tweaking will not help them achieve this form of cost reduction.
Merlin 1D was a good direction to go (and different than your Formula 1 tweaking team analogy) because they resigned primarily for manufacturability (and hence cost) and not performance. They threw in performance gains while they were at it based on what they had learned with previous Merlins.
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BTDT and it isn't fun for more than a couple of years. Any more and you realize that you missed out on a portion of your life.
I think Jim just outed himself as a "work to live" kind of guy.
May I recommend: http://www.imdb.com/title/tt1772925/
Great movie
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Given the current launch rate, why are they testing Merlin engines on a daily basis in Texas ?
Maybe working on ways to reduce engine weight? I know Formula 1 teams spend a lot of effort to save some gram per week on the cars. The season starts but they have new engine/car parts every week. One example is picking some structural element and redesigning it so it retains the same characteristics while weighting less.
No, what you suggest is almost 100% incompatible with SpaceX's philosophy, which is to optimize for cost and not performance.
Considering the engine is new and has never flown, wouldn't just learning about the engine be a priority, studying its reliability vs performance. They probably don't know enough about the engines reliability to know what it's maximum thrust/reliability value is yet. They just have a chosen design 100% thrust and so far statistically the reliability looks roughly acceptable.
Once desired thrust/reliability is confirmed, I would say simplifying and optimising fabrication for cost would be of higher priority than reducing a even 1 kg of weight.
Formula 1 cars weigh ~450kg and have a minimum race weight of ~600kg. A lot of ballast is added to them. Most of the design effort is for aerodynamics and squeezing an extra 10watts out of the engine.
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Considering the engine is new and has never flown, wouldn't just learning about the engine be a priority, studying its reliability vs performance. They probably don't know enough about the engines reliability to know what it's maximum thrust/reliability value is yet. They just have a chosen design 100% thrust and so far statistically the reliability looks roughly acceptable.
There has been a Merlin 1D flying on grasshopper for months.
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Not really. Merlin 1D is the best engine in terms of thrust/weight ratio. It is a requirement, otherwise having 9 engines would reduce performance considerably. Their 9 engines concept does not work so well with heavy engines.
You realize the point you made is irrelevant right? 100 engines or 1 engine, thrust to weight ratio is a _ratio_. Meaning 1 engine with the same thrust/weight ratio of a Merlin 1D but 9 times the thrust will have exactly the same weight as 9 Merlin 1Ds. Increasing thrust to weight is no more a requirement here than for any other rocket. So your argument that having 9 engines makes thrust/weight ratio more important is invalid.
You are forgetting two things:
1) Piping. Same T/W on the engines doesn't automatically translate to better T/W overall. The old octopus appeared to be very elegant, but it required the huge thrust structure. V1.1 arrangement takes most of the thrust directly to the tank walls. So it could have been that the square nine configuration required more mass than a single engine with same T/W, but the octagon less.
2) Engines still have scaling issues. For a given thrust they need to increase the throat area, which scales quadratically, but that implies an increased in engine volume, which is cubic. Thus, T/W of single nozzle engines tend to worsen when increasing.
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Off-topic:
Merlin 1D was a good direction to go[…] because they [redesigned] primarily for manufacturability (and hence cost) and not performance. They threw in performance gains while they were at it based on what they had learned with previous Merlins.
Please let this be how the F-1B is handled.
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There has been a Merlin 1D flying on grasshopper for months.
A few hops totaling less than 1 minute of cumulative burn time is months?
Compare to the total burn time a Merlin 1C flavor accumulated before first issue(s) were seen.
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There has been a Merlin 1D flying on grasshopper for months.
A few hops totaling less than 1 minute of cumulative burn time is months?
Compare to the total burn time a Merlin 1C flavor accumulated before first issue(s) were seen.
My least favorite thing about the Internet:
Intentionally misinterpreting someone else's post to invent "gotchas."
You could make your point just as easily without doing that.
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There has been a Merlin 1D flying on grasshopper for months.
A few hops totaling less than 1 minute of cumulative burn time is months?
Compare to the total burn time a Merlin 1C flavor accumulated before first issue(s) were seen.
My least favorite thing about the Internet:
Intentionally misinterpreting someone else's post to invent "gotchas."
You could make your point just as easily without doing that.
Actually ugordan was correctly addressing the context of the original argument.
Saying there was an engine in operation for "months" was misleading. The length of time in which it was strapped to the bottom of GH is irrelevant.
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There has been a Merlin 1D flying on grasshopper for months.
A few hops totaling less than 1 minute of cumulative burn time is months?
Compare to the total burn time a Merlin 1C flavor accumulated before first issue(s) were seen.
My least favorite thing about the Internet:
Intentionally misinterpreting someone else's post to invent "gotchas."
You could make your point just as easily without doing that.
Doing what? Pointing out that LegendCJS' comment about Merlin 1D not being new and unflown is laughable at least? I'm not misinterpreting anything, it's you who's picking a statement out of context and dissecting it. Another thing the Internet arguments are known for.
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You intentionally misinterpreted his statement as if he claimed it had been firing for months at a time. It is quite true they've been using a Merlin 1D for several months now for testing purposes in a suborbital test-bed (for short durations, but that doesn't change the fact they've been using it for testing Grasshopper for months now). Your original point is true as well, in that Merlin 1D still hasn't been used operationally in any orbital launch vehicle and thus is still a greenhorn, but you sullied your point.
Seriously, don't intentionally misinterpret other people's posts and then do the same thing AGAIN by pretending I'm agreeing with a previous point you implied he made just because I called you on it.
EDIT: Actually, you're reading into his original post.
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There has been a Merlin 1D flying on grasshopper for months.
A few hops totaling less than 1 minute of cumulative burn time is months?
Compare to the total burn time a Merlin 1C flavor accumulated before first issue(s) were seen.
My least favorite thing about the Internet:
Intentionally misinterpreting someone else's post to invent "gotchas."
You could make your point just as easily without doing that.
Actually ugordan was correctly addressing the context of the original argument.
Saying there was an engine in operation for "months" was misleading. The length of time in which it was strapped to the bottom of GH is irrelevant.
Context is important, here.
They've been testing Merlin 1D for a very long time, very often. They're test-firing (and acceptance-firing) Merlin 1Ds several times a week every week. And they were doing a heck of a lot of test-firing long before they strapped it to Merlin 1D. And the RELEVANT post that Legend was replying to (which you stripped off his quote, making it look like he was implying more than he was):
Given the current launch rate, why are they testing Merlin engines on a daily basis in Texas ?
Maybe working on ways to reduce engine weight? I know Formula 1 teams spend a lot of effort to save some gram per week on the cars. The season starts but they have new engine/car parts every week. One example is picking some structural element and redesigning it so it retains the same characteristics while weighting less.
No, what you suggest is almost 100% incompatible with SpaceX's philosophy, which is to optimize for cost and not performance.
Considering the engine is new and has never flown, wouldn't just learning about the engine be a priority, studying its reliability vs performance. They probably don't know enough about the engines reliability to know what it's maximum thrust/reliability value is yet. They just have a chosen design 100% thrust and so far statistically the reliability looks roughly acceptable....
Many of these things are design /requirements/, it's not like a gift from the aliens that they have to reverse engineer or something. They know it inside and out because they /designed/ it. They know that it will exceed such-and-such margins if they operate at such-and-such operating points. This is a little like saying the Shuttle folks had no idea about studying the reliability vs. performance of the SSME on the first launch of Shuttle... Well, in fact, they had been testing the SSME for years beforehand, long before first flight, and they had developed design requirements and done analysis on the design long before that. It's posts like this that make it seem like engineering is just a trial-by-error discipline instead of being driven by well-established empirical and semi-empirical relationships between stress, cycle-life, probability of failure, etc. And if they're flying it on a suborbital test-bed, it shows they've already done all that analysis, done extensive ground testing, and have graduated to flight demos. I'm confident they've already produced and tested at least twenty (probably thirty) Merlin 1Ds, which is a very large number compared to any other engine manufacturer in the US. They aren't clueless about the performance vs reliability of the Merlin 1D, anymore than Rocketdyne and NASA were about the SSME when Shuttle first launched on STS-1. This is just the sort of thing that ground-testing is useful for.
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I'll recap the headlines:
"Why are they firing the 1D so much?"
"Because it hasn't flown yet"
"but one has been flying on GH for months!" <--- irrelevant, misleading
ugordan: "that's irrelevant, it only fired for less than a minute"
And the rest, as they say, is history.
Shrug. Let's spend more time in the GH thread - hopefully an exciting week coming up.
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They're firing the Merlin 1D so much because they need a LOT of them (at one point, they suggested they were shooting for 8 launches this year... that's 80 Merlin 1Ds! I'll be happy if they get 3 launches) and they have to acceptance fire each one.
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There is an updated Google maps view of the Texas site which shows the Falcon Heavy stand construction, grasshopper, superdraco stand, new building etc.....
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Looks like they are digging a large flame trench - perhaps for better sound suppression?
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There is an updated Google maps view of the Texas site which shows the Falcon Heavy stand construction, grasshopper, superdraco stand, new building etc.....
Here's the partially-underground Falcon Heavy test stand:
http://goo.gl/maps/wxKG3
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There has been a Merlin 1D flying on grasshopper for months.
A few hops totaling less than 1 minute of cumulative burn time is months?
Compare to the total burn time a Merlin 1C flavor accumulated before first issue(s) were seen.
When I post on this forum about SpaceX, I assume everyone in the thread has seen all the Grasshopper videos, and therefore I did not worry about causing confusion.
I would also hazard to venture that the total burn time of all standalone Merlin 1D tests vs all standalone Merlin 1C tests is at least 1/2 by now, if not larger. I discount 3x3 grid grouped Merlin 1C testing time because those tests are to check for interaction of the engines with each other, not to figure out the engine performance curves as was the hypothesis of Karloss12's post about why so much Merlin 1D testing.
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There is an updated Google maps view of the Texas site which shows the Falcon Heavy stand construction, grasshopper, superdraco stand, new building etc.....
Here's the partially-underground Falcon Heavy test stand:
http://goo.gl/maps/wxKG3
Sorry for the slightly off topic question, but does anyone know what the strange field with what looks like sheds in a "fishbone" arrangement is to the north norht west of the teststand?
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A rough estimate of the depth of that flame pit from the height of the water tower being reportedly 280 ft, I get a depth of around 65 feet. Give or take a few feet.
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The new Google images are interesting. Here's what looks to be a standard SpaceX HIF, at McGregor. Is this known about?
69m x 23m (227' x 76')
http://wikimapia.org/#lat=31.3882981&lon=-97.4589332&z=19&l=0&m=b (http://wikimapia.org/#lat=31.3882981&lon=-97.4589332&z=19&l=0&m=b)
Edit: Add dimensions.
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Is that a first stage in the scrap yard?
http://wikimapia.org/#lat=31.3912389&lon=-97.4628576&z=19&l=0&m=b (http://wikimapia.org/#lat=31.3912389&lon=-97.4628576&z=19&l=0&m=b)
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The neatest thing (well, I can't really rank them) is the scrap yard:
https://maps.google.com/maps?q=McGregor,+TX&hl=en&ll=31.391367,-97.463004&spn=0.000735,0.001404&sll=33.95703,-118.328247&sspn=1.391925,2.469177&hnear=McGregor,+McLennan,+Texas&t=h&z=20
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The neatest thing (well, I can't really rank them) is the scrap yard:
https://maps.google.com/maps?q=McGregor,+TX&hl=en&ll=31.391367,-97.463004&spn=0.000735,0.001404&sll=33.95703,-118.328247&sspn=1.391925,2.469177&hnear=McGregor,+McLennan,+Texas&t=h&z=20
Nice find!!! Notice all the discarded thrust structures. I even spotted what looks like a v1.1 thrust structure at lat/long 31.391467, -97.462253 (just search for that at maps.google.com and view in satellite mode)
Here it is: http://goo.gl/EeaIQ
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There is an updated Google maps view of the Texas site which shows the Falcon Heavy stand construction, grasshopper, superdraco stand, new building etc.....
Here's the partially-underground Falcon Heavy test stand:
http://goo.gl/maps/wxKG3
Sorry for the slightly off topic question, but does anyone know what the strange field with what looks like sheds in a "fishbone" arrangement is to the north norht west of the teststand?
It's a military explosives storage area. The bunkers are used to prevent an explosion in one bunker from taking out the whole facility. It's decommissioned; there are even trees growing out of some of the bunkers.
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The neatest thing (well, I can't really rank them) is the scrap yard:
https://maps.google.com/maps?q=McGregor,+TX&hl=en&ll=31.391367,-97.463004&spn=0.000735,0.001404&sll=33.95703,-118.328247&sspn=1.391925,2.469177&hnear=McGregor,+McLennan,+Texas&t=h&z=20
Nice find!!! Notice all the discarded thrust structures. I even spotted what looks like a v1.1 thrust structure at lat/long 31.391467, -97.462253 (just search for that at maps.google.com and view in satellite mode)
GH is sitting dead center on its pad, and there are no scorch marks. So this is at least a tad old, as we'd expect.
When they fly GH, they're looking from the tower that's north of it, I'd assume.
On the test stand area, there's the pyramid test stand, and also a blue metal truss tower - does anyone know what that is?
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It's a military explosives storage area. The bunkers are used to prevent an explosion in one bunker from taking out the whole facility. It's decommissioned; there are even trees growing out of some of the bunkers.
Maybe some are used to store Merlins?
http://www.youtube.com/watch?v=bcYppAs6ZdI
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On the test stand area, there's the pyramid test stand, and also a blue metal truss tower - does anyone know what that is?
Structural test stand for the stages/interstage, at least it was for F9 v1.0.
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There is an updated Google maps view of the Texas site which shows the Falcon Heavy stand construction, grasshopper, superdraco stand, new building etc.....
Here's the partially-underground Falcon Heavy test stand:
http://goo.gl/maps/wxKG3
Sorry for the slightly off topic question, but does anyone know what the strange field with what looks like sheds in a "fishbone" arrangement is to the north norht west of the teststand?
It's a military explosives storage area. The bunkers are used to prevent an explosion in one bunker from taking out the whole facility. It's decommissioned; there are even trees growing out of some of the bunkers.
Ahh, I seee, thanks!
I too noticed the area that looks like a scrapyard. There are some interesting structures lying arround there. Some things look like first stages, others I am not sure about. I was wondering whether other things were just tanks of sorts for the test stand fuels that had to be discarded for some reason?
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more guess work on the McGregor google image.
Trying to match this:
http://www.youtube.com/watch?v=kwX9Ymu7t5A
to the map, based on the trees, and on the pole near the corner of the shed (at 0:19)
I think it is the shed at
https://maps.google.com/maps?q=McGregor,+TX&hl=en&ll=31.39401,-97.460546&spn=0.001102,0.001635&sll=33.95703,-118.328247&sspn=1.391925,2.469177&hnear=McGregor,+McLennan,+Texas&t=h&z=20
Just for kicks...
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more guess work on the McGregor google image.
Trying to match this:
to the map, based on the trees, and on the pole near the corner of the shed (at 0:19)
I think it is the shed at
https://maps.google.com/maps?q=McGregor,+TX&hl=en&ll=31.39401,-97.460546&spn=0.001102,0.001635&sll=33.95703,-118.328247&sspn=1.391925,2.469177&hnear=McGregor,+McLennan,+Texas&t=h&z=20
Just for kicks...
From an intern I know who actually helped build that stand, he said that stand is temporary and was only made to make the video. (The actual test stand wasn't done yet so they rigged up the test stand shown in the video in the span of a few days.) So there is a good chance that the test stand isn't in the google map.
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more guess work on the McGregor google image.
Trying to match this:
to the map, based on the trees, and on the pole near the corner of the shed (at 0:19)
I think it is the shed at
https://maps.google.com/maps?q=McGregor,+TX&hl=en&ll=31.39401,-97.460546&spn=0.001102,0.001635&sll=33.95703,-118.328247&sspn=1.391925,2.469177&hnear=McGregor,+McLennan,+Texas&t=h&z=20
Just for kicks...
From an intern I know who actually helped build that stand, he said that stand is temporary and was only made to make the video. (The actual test stand wasn't done yet so they rigged up the test stand shown in the video in the span of a few days.) So there is a good chance that the test stand isn't in the google map.
Mlinder, you are correct that the video was made on a "demo" stand. There was a NASA milestone that coincided with that test. MeekGee, good work, you are also correct about the temporary stand's location. You get a cookie.
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more guess work on the McGregor google image.
Trying to match this:
to the map, based on the trees, and on the pole near the corner of the shed (at 0:19)
I think it is the shed at
https://maps.google.com/maps?q=McGregor,+TX&hl=en&ll=31.39401,-97.460546&spn=0.001102,0.001635&sll=33.95703,-118.328247&sspn=1.391925,2.469177&hnear=McGregor,+McLennan,+Texas&t=h&z=20
Just for kicks...
From an intern I know who actually helped build that stand, he said that stand is temporary and was only made to make the video. (The actual test stand wasn't done yet so they rigged up the test stand shown in the video in the span of a few days.) So there is a good chance that the test stand isn't in the google map.
Mlinder, you are correct that the video was made on a "demo" stand. There was a NASA milestone that coincided with that test. MeekGee, good work, you are also correct about the temporary stand's location. You get a cookie.
There's a lot of people on this forum from a lot of places. Are you a SpaceX employee or current/former intern? You seem very sure of what you state so was just wondering.
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more guess work on the McGregor google image.
Trying to match this:
to the map, based on the trees, and on the pole near the corner of the shed (at 0:19)
I think it is the shed at
https://maps.google.com/maps?q=McGregor,+TX&hl=en&ll=31.39401,-97.460546&spn=0.001102,0.001635&sll=33.95703,-118.328247&sspn=1.391925,2.469177&hnear=McGregor,+McLennan,+Texas&t=h&z=20
Just for kicks...
From an intern I know who actually helped build that stand, he said that stand is temporary and was only made to make the video. (The actual test stand wasn't done yet so they rigged up the test stand shown in the video in the span of a few days.) So there is a good chance that the test stand isn't in the google map.
Mlinder, you are correct that the video was made on a "demo" stand. There was a NASA milestone that coincided with that test. MeekGee, good work, you are also correct about the temporary stand's location. You get a cookie.
There's a lot of people on this forum from a lot of places. Are you a SpaceX employee or current/former intern? You seem very sure of what you state so was just wondering.
No, but I have visited the test site and have lots of connections.
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GH is sitting dead center on its pad, and there are no scorch marks. So this is at least a tad old, as we'd expect.
I might be remembering it wrong, but didnt grasshopper lack the pointy top until after the first flight? Press photos from the September flight seem to still lack it (though it might have already been on there for the first flight and the press photos that showed the tip were older). I cant quite remember anymore.
The pointy tip is definitely on in the google maps image.
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GH is sitting dead center on its pad, and there are no scorch marks. So this is at least a tad old, as we'd expect.
I might be remembering it wrong, but didnt grasshopper lack the pointy top until after the first flight? Press photos from the September flight seem to still lack it (though it might have already been on there for the first flight and the press photos that showed the tip were older). I cant quite remember anymore.
The pointy tip is definitely on in the google maps image.
Yeah, I saw, posted it too later on. so it's not that old. I have cookie I can pass along!
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GH is sitting dead center on its pad, and there are no scorch marks. So this is at least a tad old, as we'd expect.
I might be remembering it wrong, but didnt grasshopper lack the pointy top until after the first flight? Press photos from the September flight seem to still lack it (though it might have already been on there for the first flight and the press photos that showed the tip were older). I cant quite remember anymore.
The pointy tip is definitely on in the google maps image.
Google Earth has the same image, where it's dated as 12/11/2012.
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GH is sitting dead center on its pad, and there are no scorch marks. So this is at least a tad old, as we'd expect.
I might be remembering it wrong, but didnt grasshopper lack the pointy top until after the first flight? Press photos from the September flight seem to still lack it (though it might have already been on there for the first flight and the press photos that showed the tip were older). I cant quite remember anymore.
The pointy tip is definitely on in the google maps image.
Google Earth has the same image, where it's dated as 12/11/2012.
Where in Google Earth are you seeing that date? I can't seem to find it.
Also, is that in MM/DD/YYYY format or DD/MM/YYYY format?
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Considering the engine is new and has never flown, wouldn't just learning about the engine be a priority, studying its reliability vs performance. They probably don't know enough about the engines reliability to know what it's maximum thrust/reliability value is yet. They just have a chosen design 100% thrust and so far statistically the reliability looks roughly acceptable.
There has been a Merlin 1D flying on grasshopper for months.
What does that have to do studying the Merlin's performance vs reliability. The grasshopper tests are for developing the hovering and landing control systems, not for studying the internal goings on of the engine its self.
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Considering the engine is new and has never flown, wouldn't just learning about the engine be a priority, studying its reliability vs performance. They probably don't know enough about the engines reliability to know what it's maximum thrust/reliability value is yet. They just have a chosen design 100% thrust and so far statistically the reliability looks roughly acceptable.
There has been a Merlin 1D flying on grasshopper for months.
What does that have to do studying the Merlin's performance vs reliability. The grasshopper tests are for developing the hovering and landing control systems, not for studying the internal goings on of the engine its self.
Do you have some documentation for that claim?
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Logic?
There is nothing the engine does on Grasshopper that can't be done on a test stand. And test stands are always more desirable, as they have far more instrumentation (pressure sensors, thermal sensors, cameras, IR imagers, etc) than you could possibly put on a flight vehicle.
Grasshopper is for flight testing of control systems. It's no more deeper or complex than that.
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Logic?
There is nothing the engine does on Grasshopper that can't be done on a test stand. And test stands are always more desirable, as they have far more instrumentation (pressure sensors, thermal sensors, cameras, IR imagers, etc) than you could possibly put on a flight vehicle.
Grasshopper is for flight testing of control systems. It's no more deeper or complex than that.
But test stands can only take you so far... You cannot simulate in-flight use 100% - the last F9 flight may be an example of that. In addition, GH will be invaluable for testing restarts in atmospheric free fall, something you otherwise would not be able to test until a full-up F9R flight.
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Logic?
There is nothing the engine does on Grasshopper that can't be done on a test stand. And test stands are always more desirable, as they have far more instrumentation (pressure sensors, thermal sensors, cameras, IR imagers, etc) than you could possibly put on a flight vehicle.
Grasshopper is for flight testing of control systems. It's no more deeper or complex than that.
But test stands can only take you so far... You cannot simulate in-flight use 100% - the last F9 flight may be an example of that. In addition, GH will be invaluable for testing restarts in atmospheric free fall, something you otherwise would not be able to test until a full-up F9R flight.
The original claim was that the grasshopper tests completed so far are being used to study the performance vs reliability of the Merlin engine. Common sense says that everything that the Merlin has done on the grasshopper so far can be done with less fuss in a test stand. Therefore the tests so far were for developing the control systems that will be used for recovery.
Yes, future tests for reigniting will need to be using actual free fall with the engine having plenty of sensors, data, analysis and potentially design improvements. Testing high speed re-entry conditions on a test stand would be to difficult or impossible.
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Test stands work pretty well for verifying reliability.
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GH is sitting dead center on its pad, and there are no scorch marks. So this is at least a tad old, as we'd expect.
I might be remembering it wrong, but didnt grasshopper lack the pointy top until after the first flight? Press photos from the September flight seem to still lack it (though it might have already been on there for the first flight and the press photos that showed the tip were older). I cant quite remember anymore.
The pointy tip is definitely on in the google maps image.
Google Earth has the same image, where it's dated as 12/11/2012.
Where in Google Earth are you seeing that date? I can't seem to find it.
Also, is that in MM/DD/YYYY format or DD/MM/YYYY format?
Here's a screen shot from my laptop. Check the lower left hand corner of the ground image.
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Happy Year of the Snake (Dragon) !
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Happy Year of the Snake (Dragon) !
Last year was Dragon.
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If you guys want to analyze imagery of McGregor or anywhere else, you're much better off using Google Earth than Google Maps. In Earth, go up to the "view" menu and click on "historical imagery", a box with slider bar will appear in the upper left hand corner. You can easily compare images from different dates (dates are shown) by clicking the forward and back buttons. Changes become obvious as you flip back and forth.
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If you guys want to analyze imagery of McGregor or anywhere else, you're much better off using Google Earth than Google Maps. In Earth, go up to the "view" menu and click on "historical imagery", a box with slider bar will appear in the upper left hand corner. You can easily compare images from different dates (dates are shown) by clicking the forward and back buttons. Changes become obvious as you flip back and forth.
Wow, thanks for the tip. I hadn't realized how much of this stuff was all from SpaceX. I had thought there was some existing infrastructure before they moved in, but there was really hardly nothing. They've built a tremendous amount of infrastructure during just the last 3-4 years. End of 2008 they had one testing infrastructure and looks like one was in construction. Come 2012 though there are several and the existing ones have doubled in size.
This reminds me of something one of the engineers that was at the recruiting fair here awhile back said. He mentioned how that it seemed like all the time at the McGregor facility there would suddenly be new doors in rooms that weren't there before and that it happened all the time. Obviously embellishing it of course, but they are expanding pretty fast.
Anyone who has worked at NASA testing facilities, are there often additions being added to the complex or are things relatively fixed?
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If you guys want to analyze imagery of McGregor or anywhere else, you're much better off using Google Earth than Google Maps. In Earth, go up to the "view" menu and click on "historical imagery", a box with slider bar will appear in the upper left hand corner. You can easily compare images from different dates (dates are shown) by clicking the forward and back buttons. Changes become obvious as you flip back and forth.
Wow, thanks for the tip. I hadn't realized how much of this stuff was all from SpaceX. I had thought there was some existing infrastructure before they moved in, but there was really hardly nothing. They've built a tremendous amount of infrastructure during just the last 3-4 years. End of 2008 they had one testing infrastructure and looks like one was in construction. Come 2012 though there are several and the existing ones have doubled in size.
This reminds me of something one of the engineers that was at the recruiting fair here awhile back said. He mentioned how that it seemed like all the time at the McGregor facility there would suddenly be new doors in rooms that weren't there before and that it happened all the time. Obviously embellishing it of course, but they are expanding pretty fast.
Anyone who has worked at NASA testing facilities, are there often additions being added to the complex or are things relatively fixed?
Google Earth can be your friend there too...
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I have a question.
How much longer do you think SpaceX can last without improving their flight rate? When does the industry start to write them off as "empty promises" and start pulling launch contracts? It seems to me that this is growing into the veritable "elephant in the room" for SpaceX despite all of their great accomplishments so far.
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Paying customers will pull contracts when it's clear to them that SpaceX won't be able to meet their needs. What's most important is: when do those customers want to be on orbit? They make no money if their spacecraft is sitting on the ground waiting for a launch vehicle. So most of those commercial customers probably have backup vehicles booked, and if SpaceX doesn't meet milestones, those customers will switch to the backup. It's all going to be done on a case by case basis, so I doubt you'd see a mass exodus unless there was clearly an issue with the launch vehicle.
Since I don't know the nature of those commercial contracts, I can't say whether it's an elephant or a mouse in the room at this time. Whatever it is, it's going to grow until SpaceX proves the F9 v1.1 design with the 5m fairing, starts producing enough vehicles to satisfy the manifest on time, and flies those vehicles successfully.
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Yeah, I guess I am just starting to grow anxious as there always seems to be one more thing to clear. ("as soon as we get f9 flying", "as soon as we get CRS down", "as soon as we get f8 v1.1"...)
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Will Dragon or Cygnus eventually also use the 6 hour flight option that was demonstrated today by the Russian Progress freighter?
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I don't think there is a requirement for it in the current CRS contracts, but there is also nothing preventing them from trying first-orbit rendezvous if they get the procedure down well enough.
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According to this (http://www.newspacewatch.com/articles/bolden-tours-spacex-at-vandenberg-first-launch-set-for-june.html) there is a lunch date set for CASSIOPE from Vandenberg on June 18th this year.
I would have posted this in the mission section but I could not find a mission thread for this mission. I hope posting here is also ok.
Cheers,
Kasei
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According to this (http://www.newspacewatch.com/articles/bolden-tours-spacex-at-vandenberg-first-launch-set-for-june.html) there is a lunch date set for CASSIOPE from Vandenberg on June 18th this year.
I would have posted this in the mission section but I could not find a mission thread for this mission. I hope posting here is also ok.
Cheers,
Kasei
Welcome to the site.
How about right here: http://forum.nasaspaceflight.com/index.php?topic=22085.msg610311#msg610311
Also try the search feature on this site using "CASSIOPE" for other post concerning this.
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Yeah, I guess I am just starting to grow anxious as there always seems to be one more thing to clear. ("as soon as we get f9 flying", "as soon as we get CRS down", "as soon as we get f8 v1.1"...)
SpaceX needs to remember that flying a satellite to LEO requires a fairing but does not require life support. Production of Falcon 9s can now be separated from development of the Dragon.
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Yeah, I guess I am just starting to grow anxious as there always seems to be one more thing to clear. ("as soon as we get f9 flying", "as soon as we get CRS down", "as soon as we get f8 v1.1"...)
SpaceX needs to remember that flying a satellite to LEO requires a fairing but does not require life support. Production of Falcon 9s can now be separated from development of the Dragon.
Seriously?
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Yeah, I guess I am just starting to grow anxious as there always seems to be one more thing to clear. ("as soon as we get f9 flying", "as soon as we get CRS down", "as soon as we get f8 v1.1"...)
SpaceX needs to remember that flying a satellite to LEO requires a fairing but does not require life support. Production of Falcon 9s can now be separated from development of the Dragon.
Seriously?
I'll be generous and assume that AMS is making a serious point rather than insulting everyone with a blinding flash of the obvious. On this subject - Is there any talk about SpaceX opening a new factory building for Dragon or Falcon and to completely focus the existing production building on the other?
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Bing maps imagery isn't as current as Google maps, so it does offer the ability see how much work has been done since the image was taken. It is a shame that the image isn't current because Bing gives the ability to see the image from all sides of the compass at an oblique angle by clicking the curved arrows near the upper right of the image.
http://binged.it/YWYEUU
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Yeah, I guess I am just starting to grow anxious as there always seems to be one more thing to clear. ("as soon as we get f9 flying", "as soon as we get CRS down", "as soon as we get f8 v1.1"...)
SpaceX needs to remember that flying a satellite to LEO requires a fairing but does not require life support. Production of Falcon 9s can now be separated from development of the Dragon.
Seriously?
I'll be generous and assume that AMS is making a serious point rather than insulting everyone with a blinding flash of the obvious. On this subject - Is there any talk about SpaceX opening a new factory building for Dragon or Falcon and to completely focus the existing production building on the other?
Just consider
This is 2013.
SpaceX has a backlog of payloads.
First Falcon 9 flew in 2010.
No flights in 2011.
Dragons on Falcon 9s docked with ISS in 2012.
No fairing flights, yet.
Why?
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Simple. They didn't need it yet. CRS took the lead as far as contract obligations. The Fairing has been undergoing testing and will be used this year (June). So my question is why the rush to judgement.
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Just consider
This is 2013.
SpaceX has a backlog of payloads.
First Falcon 9 flew in 2010.
No flights in 2011.
Dragons on Falcon 9s docked with ISS in 2012.
No fairing flights, yet.
Why?
AMS you have been in here for years, you know why. :)
CRS/COTS was/is the only contract SpaceX has with certain members of Congress wanting to defund it. In a situation where some of your customers are Aerospace professionals who understand your a start up and scheduled backups because they understand what the word NET means, and others of your customers are itching to cancel your largest contract so they can increase the funding for their favorite rocket program by a few percentage points. You oil the squeaky cog.
That added onto the fact that Falcon 1.0 under performed and the fairing had issues in simulations the smartest thing to do is focus on giving Congress as little reason as possible to defund COTS/CRS and focus your production capacity on the less flawed Falcon 9 1.1/Falcon Heavy.
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Underperforming? Well as far as specs vs. projected specs sure but, it did deliver a successful test launch, one test Dragon to orbit and two Dragons to the ISS.Not a bad track record so far for a launch vehicle that will launch only a total of 5 times.
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Underperforming? Well as far as specs vs. projected specs sure but, it did deliver a successful test launch, one test Dragon to orbit and two Dragons to the ISS.Not a bad track record so far for a launch vehicle that will launch only a total of 5 times.
100% agree, just because Falcon 9 1.0 never performed as well as intended does not mean it was a failure. Luckily SpaceX has the ability to take the pain early and restart a flawed launch vehicle program instead of flying it for 30 years.
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On a different note, after this upcoming launch, I would like to see an objective article or objective board about Falcon 1.0 listing it's overall track record with a per launch performance breakdown.
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AMS has a valid point. Why does concentration to COTS/CRS delay F-9s for other uses, are the people/equipment in F-9 production required in Dragon mfg?
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AMS has a valid point. Why does concentration to COTS/CRS delay F-9s for other uses, are the people/equipment in F-9 production required in Dragon mfg?
No, it is not a valid point. The delays are due to pad throughput and Falcon issues (redesign) and not Dragon.
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The delays are due to pad throughput and Falcon issues (redesign) and not Dragon.
Pad throughput? What's been holding back things there?
F-9 is getting redesigned, but was there no possibility to do sort of production run for limited number of 1.0 (it did work after all), without delaying the redesign process?
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The delays are due to pad throughput and Falcon issues (redesign) and not Dragon.
Pad throughput? What's been holding back things there?
Dragon moved schedules to the right pretty heftily, especially the COTS delays.
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The pad and hangar can only process one flight at a time. That is one of the reasons.
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Thanks, Chris-A, that cleared a lot!
I've been under impression that F-9 spends only little time on the pad. Hypothetically, two parallel hangars would have enabled higher throughput? If one has delay switch launch order and roll out the other to the pad. (oversimplified, I know)
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I think that part of the issue was that SpaceX was under a lot of pressure. Everyone was watching them. Many with alterior motives, particularly among the politicians were hoping for them to fail.
A catastropic failure would have probably been enough for certain congressmen to ask for a cancellation of COTS and CCDev.
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How much processing can SpaceX do at their other building-for-storing-rockets at the Cape? I've heard you can fit maybe a couple Falcon 9s in there, but is it possible to do any kind of launch vehicle processing there? (My assumption would be "no", but I'm curious.)
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CRS/COTS was/is the only contract SpaceX has with certain members of Congress wanting to defund it. In a situation where some of your customers are Aerospace professionals who understand your a start up and scheduled backups because they understand what the word NET means, and others of your customers are itching to cancel your largest contract so they can increase the funding for their favorite rocket program by a few percentage points. You oil the squeaky cog.
That added onto the fact that Falcon 1.0 under performed and the fairing had issues in simulations the smartest thing to do is focus on giving Congress as little reason as possible to defund COTS/CRS and focus your production capacity on the less flawed Falcon 9 1.1/Falcon Heavy.
"How SpaceX saved Cygnus" :D
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CRS/COTS was/is the only contract SpaceX has with certain members of Congress wanting to defund it. In a situation where some of your customers are Aerospace professionals who understand your a start up and scheduled backups because they understand what the word NET means, and others of your customers are itching to cancel your largest contract so they can increase the funding for their favorite rocket program by a few percentage points. You oil the squeaky cog.
That added onto the fact that Falcon 1.0 under performed and the fairing had issues in simulations the smartest thing to do is focus on giving Congress as little reason as possible to defund COTS/CRS and focus your production capacity on the less flawed Falcon 9 1.1/Falcon Heavy.
"How SpaceX saved Cygnus" :D
If SpaceX had not been doing so well under COTS when Kistler went under, I think you would have seen much more serious talk about scraping the whole program.
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AMS has a valid point. Why does concentration to COTS/CRS delay F-9s for other uses, are the people/equipment in F-9 production required in Dragon mfg?
No, it is not a valid point. The delays are due to pad throughput and Falcon issues (redesign) and not Dragon.
Technically, they could have launched some of their "commerical" payloads while waiting for the engineers to straighten out the Dragon software issues. It is wrong to say they didn't need the fairing. It is requirement for them to launch all of the non-CRS flights on their manifest.
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AMS has a valid point. Why does concentration to COTS/CRS delay F-9s for other uses, are the people/equipment in F-9 production required in Dragon mfg?
No, it is not a valid point. The delays are due to pad throughput and Falcon issues (redesign) and not Dragon.
Technically, they could have launched some of their "commerical" payloads while waiting for the engineers to straighten out the Dragon software issues. It is wrong to say they didn't need the fairing. It is requirement for them to launch all of the non-CRS flights on their manifest.
Most of their commercial payloads needed more performance
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Most of their commercial payloads needed more performance
Most of their commercial payloads needed (and many still need) more time.
It's not like SpaceX has some big Raiders Of The Lost Ark warehouse where they're piling up the satellites they've yet to launch.
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It's not like SpaceX has some big Raiders Of The Lost Ark warehouse where they're piling up the satellites they've yet to launch.
No, because customers went to other LVs since SpaceX wasn't ready.
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It's not like SpaceX has some big Raiders Of The Lost Ark warehouse where they're piling up the satellites they've yet to launch.
No, because customers went to other LVs since SpaceX wasn't ready.
IIRC, they still have some 48(?) flights on their manifest, so it is certainly not like customers left them in droves...
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Speaking of Falcon 9 version 1.1. The first flight of version 1.1 will be the MDA flight from Vandenberg, right?
Are the flights on the SpaceX website in the correct order? FH is the next flight after the MDA flight?
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Speaking of Falcon 9 version 1.1. The first flight of version 1.1 will be the MDA flight from Vandenberg, right?
Are the flights on the SpaceX website in the correct order? FH is the next flight after the MDA flight?
Note that the dates are when the hardware arrives, not the launch.
The first flight after the MDA should be CRS3, I would imagine.
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Speaking of Falcon 9 version 1.1. The first flight of version 1.1 will be the MDA flight from Vandenberg, right?
Are the flights on the SpaceX website in the correct order? FH is the next flight after the MDA flight?
First 1.1 is MDA, yes. But the manifest is a travesty. I wouldn't give it a high chance of reflecting SpaceX's actual plans. FH will probably be many flights later.
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FH demo might be the next flight for them from VAFB, though. But it all depends on how well the FH development is going, otherwise another v1.1 might go first.
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OK, thanks to both of you. That makes more sense.
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IIRC, they still have some 48(?) flights on their manifest, so it is certainly not like customers left them in droves...
At least MDA has been patient, Cassiope was supposed to go up in 2007/2008. It's container probably does look like the ark in Raiders of the Lost Ark!
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FH demo might be the next flight for them from VAFB, though. But it all depends on how well the FH development is going, otherwise another v1.1 might go first.
I believe that it is the other way around. The consolidated launch schedule (http://forum.nasaspaceflight.com/index.php?topic=8184.msg1010120#msg1010120) has MDC / Cassiope scheduled for June 18th on a v1.1 from VAFB.
As we just saw the Falcon Heavy erector structure partially assembled in the SpaceX hangar at VAFB. Can we assume that SpaceX will also launch the single body F9 from the same erector?
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I meant that FH might be the next flight from VAFB *after* the MDA 1.1 flight.
And yes, both v1.1 and FH will launch from the same pad using the same erector.
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I post a reply by edkyle on the ATK push for US space flight independence via Liberty thread.
SuperDraco's nominal burn time is only five seconds. It would have to burn for several minutes at a time if used for primary propulsion.
- Ed Kyle
It is an interesting and important point. It also makes sense that it is severely burn time restricted as it is designed as a lightweight small engine for abort and short landing burns.
Some of us (me for example) have anticipated the Super Draco as the main engine for a Dragon ServiceModule or for a moon lander. If the burntime is that restricted those uses would not be possible.
But is Super Draco really that restricted? It may well be as it is mounted inside covers on the Dragon. But could it burn much longer when it is mounted as a main engine that can radiate heat freely?
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If they need a new engine for in-space propulsion, they will develop it. They have plenty of experience in engine development now. But you could imagine SuperDraco as a starting point for such an engine.
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I post a reply by edkyle on the ATK push for US space flight independence via Liberty thread.
SuperDraco's nominal burn time is only five seconds. It would have to burn for several minutes at a time if used for primary propulsion.
- Ed Kyle
It is an interesting and important point. It also makes sense that it is severely burn time restricted as it is designed as a lightweight small engine for abort and short landing burns.
Some of us (me for example) have anticipated the Super Draco as the main engine for a Dragon ServiceModule or for a moon lander. If the burntime is that restricted those uses would not be possible.
But is Super Draco really that restricted? It may well be as it is mounted inside covers on the Dragon. But could it burn much longer when it is mounted as a main engine that can radiate heat freely?
You are missing the obvious - the couple of seconds of burn time is due to the limited propellant supply. Can it burn longer if given larger tanks of propellant? Surely, but only SpaceX knows the thermal limitations.
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You are missing the obvious - the couple of seconds of burn time is due to the limited propellant supply. Can it burn longer if given larger tanks of propellant? Surely, but only SpaceX knows the thermal limitations.
I am not missing that point. I am sure edkyle99 did not think of fuel supply when he mentioned the burntime limit. Also when building for example a Dragon SM there would be obviously enough propellant for the purpose. However unlike the 8 Super Dracos in Dragon there would be only one or two of them with much longer burn time even with the same amount of propellant. So it is the thermal issue I was thinking of.
So would there be thermal issues with Super Dracos not installed inside a Dragon for a long term burn? Would they require minor design adaptions or would they require a new design?
Certainly a Super Draco for main propulsion would need a much larger engine bell for increased ISP in vacuum as one modification.
Edit: Your point that only SpaceX would know exactly is correct, I agree.
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So would there be thermal issues with Super Dracos not installed inside a Dragon for a long term burn? Would they require minor design adaptions or would they require a new design?
Would need to know how SuperDraco does the cooling now. Is it just a heatsink, that would suit LAS usage. The powered landing imagery suggests longer sustained burns, that denotes ablative or regen cooling (would just thin film cooling hack it, dunno). Can't have sustained engine burn with just radiative cooling, CC would glow white hot (well yeah maybe one made out of tungsten...heavy!)
edit: heatsink means the walls suck the short duration heat impulse and then radiate it away at slower rate when engine is off. Engine cannot run long to reach thermal equilibrium, it would melt.
Certainly a Super Draco for main propulsion would need a much larger engine bell for increased ISP in vacuum as one modification.
Yes, and the nozzle extension can be radiatively cooled, like in Kestrel and MVac.
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Would need to know how SuperDraco does the cooling now. Is it just a heatsink, that would suit LAS usage. The powered landing imagery suggests longer sustained burns, that denotes ablative or regen cooling (would just thin film cooling hack it, dunno). Can't have sustained engine burn with just radiative cooling, CC would glow white hot (well yeah maybe one made out of tungsten...heavy!)
edit: heatsink means the walls suck the short duration heat impulse and then radiate it away at slower rate when engine is off. Engine cannot run long to reach thermal equilibrium, it would melt.
Nice explanation of heat sink. :)
I believe the powered landing can still be achieved without regen cooling. The burn is not that long and I am sure they have that covered as it is a short time goal. Ablative cooling is not what they want for reusability so unlikely IMO.
An engine not enclosed like the Dragon abort engines can radiate better and don't heat up the vehicle the same way so may have somewhat longer burn times but still short unless SD has regen cooling which seems unlikely. So probably not suitable as a SM engine unless pulsed with sufficient pause for cooling.
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I presume that super-Draco has a wide throttle range? To allow it to provide a high-g abort yet also deliver a soft landing with a crew.
Or are we assuming that this will be another 'stick' landing at full throttle?
Presumably throttle setting has a significant impact upon thermal build up.
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On a different topic, and apologies if this has been discussed at length, what would be the implications/benefits/likelihood or a SpaceX/SeaLaunch tie-up?
What comes to mind is that, if SeaLaunch goes under and the assets are sold, the launch platform is a rather handy potential up-range launch site catering for a Kerolox vehicle of similar dimensions to a F9.
With all the suggestions about down-range recovery, it seems to me that a mobile launch location makes a lot of sense. You could have a single recovery location and adjust the launch site for different inclinations.
I suppose one obvious drawback would be that the platform is presumably not big enough for FH.
I would hate to see the SeaLaunch infrastructure go to waste- it's an amazing concept.
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With SpaceX aiming for a 2015 non NASA Crewed visit to the ISS would they have already started astronaut selection or would they put that off until their system is more defined?
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They might already have their crew selected
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On a different topic, and apologies if this has been discussed at length,
I suppose one obvious drawback would be that the platform is presumably not big enough for FH.
I would hate to see the SeaLaunch infrastructure go to waste- it's an amazing concept.
It is an amazing concept, but it must be pretty expensive to maintain and operate the platform and the command ship. I think there is essentially zero chance that SpaceX will have anything to do with it. It's not as if they don't have enough on their plate.
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On a different topic, and apologies if this has been discussed at length, what would be the implications/benefits/likelihood or a SpaceX/SeaLaunch tie-up?
What comes to mind is that, if SeaLaunch goes under and the assets are sold, the launch platform is a rather handy potential up-range launch site catering for a Kerolox vehicle of similar dimensions to a F9.
With all the suggestions about down-range recovery, it seems to me that a mobile launch location makes a lot of sense. You could have a single recovery location and adjust the launch site for different inclinations.
I suppose one obvious drawback would be that the platform is presumably not big enough for FH.
I would hate to see the SeaLaunch infrastructure go to waste- it's an amazing concept.
IMO, it's like KSC's Crawler Transporters, only more so.
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It wanted to ask about this again in the hopes of getting a definitive answer.
Here are pictures of Orion, CST 100 and Dragon showing the orthogrid structure. Orion and CST 100 have the ribs on the outside, Dragon on the inside.
I tried to find some equivalent pictures of other capsules, Apollo, Gemini, Mercury to see what arrangement they used to no avail.
It seems there must be some important reason as to why they are one way or the other.
What is the reason?
Is Dragon doing some thing different than previous capsules or are there other examples of capsules with the ribs on the inside?
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Is Dragon doing some thing different than previous capsules or are there other examples of capsules with the ribs on the inside?
Dragon's ribs are added (friction stir welded) to the panel whereas the others are machined into the panel. I expect the inside-outside difference is just a result of the different processes used to make each.
.. but that's just my wild guess.
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Why not consider using the Delta-K or similar as the third stage since a variant of AJ-10 should remain in production for Orion?
It would have to be bigger than the Delta second stage, which only grosses a bit less than 7 tonnes (compared to 19 tonnes for ESC-A, 14 tonnes for Castor 30, etc.). Transtage, which used two AJ-10 engines, weighed about 12.5 tonnes at liftoff, so something about that size starts to be feasible. Note that Titan 3C and 34D - rockets just below Liberty class capability - used that very stage for GTO-GEO missions. (There are still numerous Transtages out there in orbit, but the last one lifted off in 1989.)
- Ed Kyle
It occurs to me if SpaceX will sell SuperDraco engines. A SuperDraco is roughly the same performance as the 2 AJ-10 on the Transtage. Also you don't have to deal with Aerozine 50 as a propellant.
SuperDraco's nominal burn time is only five seconds. It would have to burn for several minutes at a time if used for primary propulsion.
- Ed Kyle
I presume the limited tankage within the Dragon is why the nominal burn time is 5 seconds.
Only suggest the SuperDraco because it's going to be in mass production.
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No, I've seen pictures of the panels, they come in as one piece and the material between the ribs is machined out. Then they are rolled into shape. The ribs are not welded on.
Edit: CorrodedNut suggested that exterior ribs maybe machined after forming.
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No, I've seen pictures of the panels, they come in as one piece and the material between the ribs is machined out. Then they are rolled into shape. The ribs are not welded on.
When?
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Is Dragon doing some thing different than previous capsules or are there other examples of capsules with the ribs on the inside?
Dragon's ribs are added (fiction stir welded) to the panel whereas the others are machined into the panel. I expect the inside-outside difference is just a result of the different processes used to make each.
.. but that's just my wild guess.
how does stir-welding a rib onto a sheet work? I can't see the geometry in my head.
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No, I've seen pictures of the panels, they come in as one piece and the material between the ribs is machined out. Then they are rolled into shape. The ribs are not welded on.
When?
Page 15 of this thread
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No, I've seen pictures of the panels, they come in as one piece and the material between the ribs is machined out. Then they are rolled into shape. The ribs are not welded on.
When?
Page 15 of this thread
I assume you mean Joek's comment:
http://forum.nasaspaceflight.com/index.php?topic=30385.msg1005430#msg1005430
The pictures do not indicate how the panels are made, just that they're bent and welded together after they've been made.
In any case, corrodedNut answered the question of why Orion's ribs are on the outside:
http://forum.nasaspaceflight.com/index.php?topic=30385.msg1005398#msg1005398
Unless I'm mistaken, Orion's panels or sections are bent, welded, and then machined on a large multi-axis milling machine. It's probably a lot easier to machine the outside of the hull than the inside.
If there's a later post contradicting him, I don't see it.
Isn't Kremlinology fun? :)
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The only stir welding process that I know of is good for attaching flat sheets to each other, to make a "bigger" sheet.
It's a really impressive process, but I am not sure how it can be applied to attaching a rib to a flat sheet.
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Isn't Kremlinology fun? :)
Indeed, which is why I asked the question again :)
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The only stir welding process that I know of is good for attaching flat sheets to each other, to make a "bigger" sheet.
It's a really impressive process, but I am not sure how it can be applied to attaching a rib to a flat sheet.
They also make the stringers using a friction stir welding process. I vaguely remember Elon talking about how they can make much larger stringers than others because of this process. If anyone knows when that was, I'd love the video (or audio).
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In any case, corrodedNut answered the question of why Orion's ribs are on the outside:
I can't explain "why", but I'll try with the "how". Dragon's orthogrid panels are machined first, then they're bent, then welded together. Unless I'm mistaken, Orion's panels or sections are bent, welded, and then machined on a large multi-axis milling machine. It's probably a lot easier to machine the outside of the hull than the inside.
Yes, I thought this sounded very plausible, but why the two ways of doing it? Is SpaceX the first/only ones to do it this way? What's the advantage?
Edit: If the stringers, are indeed welded on that would explain it.
Of course then the question becomes what are the advantages of having the stringers on the inside.
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Yes, I thought this sounded very plausible, but why the two ways of doing it?
There's more than one way to do lots of things. :)
Is SpaceX the first/only ones to do it this way?
No idea.
What's the advantage?
Well, not having to have a ridiculously expensive multi-axis milling machine comes to mind. Instead, they just use their existing rolling welding hardware.
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The only stir welding process that I know of is good for attaching flat sheets to each other, to make a "bigger" sheet.
It's a really impressive process, but I am not sure how it can be applied to attaching a rib to a flat sheet.
They also make the stringers using a friction stir welding process. I vaguely remember Elon talking about how they can make much larger stringers than others because of this process. If anyone knows when that was, I'd love the video (or audio).
The stir welding that I know creates a butt weld.
I am not sure how stringers are made, but they look to me like roll-formed sheet metal profiles, and those can be made arbitrarily long.
Attaching them to the tank wall - I don't know. I'd have guessed it was a current (spot, line) weld process, but I don't know how these alloys behave in such a process. Also remember that any welding done on assembly affects any heat treatments or cold strain that was present, and you need to be very careful about introducing distortions. There is a lot of know-how involved.
Welding in general is always quirky. There are a lot of processes that fall under "welding", and each has its own idiosyncrasies.
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I am not sure how stringers are made, but they look to me like roll-formed sheet metal profiles, and those can be made arbitrarily long.
My understanding is that SpaceX is using an additive process to make their stringers.. but I don't recall where I heard that.. probably in that same Elon interview. Anyone?
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In any case, corrodedNut answered the question of why Orion's ribs are on the outside:
I can't explain "why", but I'll try with the "how". Dragon's orthogrid panels are machined first, then they're bent, then welded together. Unless I'm mistaken, Orion's panels or sections are bent, welded, and then machined on a large multi-axis milling machine. It's probably a lot easier to machine the outside of the hull than the inside.
Yes, I thought this sounded very plausible, but why the two ways of doing it? Is SpaceX the first/only ones to do it this way? What's the advantage?
Not sure about Orion, but for CST-100 they use spin-forming of the upper and lower pressure vessel. That precludes machining the panels first--there are no "panels", only the two halves of the pressure vessel which are subsequently bolted together (not welded). That suggests corrodedNut's explanation that machining from the outside would be much simpler. It may be that SpaceX is behind the curve in this particular technique, or that they've determined their technique is adequate/better, or maybe simply that's what they have the know-how to do reliably. Hard to tell.
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I am not sure how stringers are made, but they look to me like roll-formed sheet metal profiles, and those can be made arbitrarily long.
My understanding is that SpaceX is using an additive process to make their stringers.. but I don't recall where I heard that.. probably in that same Elon interview. Anyone?
Additive processes - as in metal deposition? ("printing")? that would be very impressive. I know there was work on that for addition Ti flanges and anchor points to thin sheets, but didn't know it was advanced enough to make an entire stringer. Are you sure?
Spin-forming pressure domes is the most reasonable way to make them. It is a process that I personally very much like.
You could, in principle, stir-weld a spin formed dome onto a rolled tank.
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Additive processes - as in metal deposition? ("printing")? that would be very impressive. I know there was work on that for addition Ti flanges and anchor points to thin sheets, but didn't know it was advanced enough to make an entire stringer. Are you sure?
Obviously I'm not sure.. it's a vague memory of an interview I can't find (like most information we get out of SpaceX).
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Why not consider using the Delta-K or similar as the third stage since a variant of AJ-10 should remain in production for Orion?
It would have to be bigger than the Delta second stage, which only grosses a bit less than 7 tonnes (compared to 19 tonnes for ESC-A, 14 tonnes for Castor 30, etc.). Transtage, which used two AJ-10 engines, weighed about 12.5 tonnes at liftoff, so something about that size starts to be feasible. Note that Titan 3C and 34D - rockets just below Liberty class capability - used that very stage for GTO-GEO missions. (There are still numerous Transtages out there in orbit, but the last one lifted off in 1989.)
- Ed Kyle
It occurs to me if SpaceX will sell SuperDraco engines. A SuperDraco is roughly the same performance as the 2 AJ-10 on the Transtage. Also you don't have to deal with Aerozine 50 as a propellant.
SuperDraco's nominal burn time is only five seconds. It would have to burn for several minutes at a time if used for primary propulsion.
- Ed Kyle
I'd be willing to bet SuperDraco is regen. It certainly isn't ablative, though I suppose it could be film-cooled. Either way, it reaches steady-state very quickly (within a few seconds) and could as well be fired for minutes as seconds. (Of course, qualifying the engine for longer would be necessary, but I see nothing fundamentally different.)
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Additive processes - as in metal deposition? ("printing")? that would be very impressive. I know there was work on that for addition Ti flanges and anchor points to thin sheets, but didn't know it was advanced enough to make an entire stringer. Are you sure?
Obviously I'm not sure.. it's a vague memory of an interview I can't find (like most information we get out of SpaceX).
no worries... we also kinda mixed the discussion about Dragon and fuel-tank manufacturing, and I don't think they are the same.
I need to get a factory tour...
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I'd be willing to bet SuperDraco is regen. It certainly isn't ablative, though I suppose it could be film-cooled. Either way, it reaches steady-state very quickly (within a few seconds) and could as well be fired for minutes as seconds. (Of course, qualifying the engine for longer would be necessary, but I see nothing fundamentally different.)
Agree it's unlikely ablative, but what makes you think it's regen? Or could fire for minues?
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I'd be willing to bet SuperDraco is regen. It certainly isn't ablative, though I suppose it could be film-cooled. Either way, it reaches steady-state very quickly (within a few seconds) and could as well be fired for minutes as seconds. (Of course, qualifying the engine for longer would be necessary, but I see nothing fundamentally different.)
Agree it's unlikely ablative, but what makes you think it's regen? Or could fire for minues?
Because non-ablative rocket engines reach equilibrium very quickly. It sure as hell isn't a heat-sink engine.
The only other option is film cooling, which for our purposes is very similar (though lower Isp).
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Here's another factory tour on the Seimens commercial I saw this morning. It's on Youtube: http://youtu.be/U1EJinxpx4Y
You can see a little more assembly work going on in this video.
Additive processes - as in metal deposition? ("printing")? that would be very impressive. I know there was work on that for addition Ti flanges and anchor points to thin sheets, but didn't know it was advanced enough to make an entire stringer. Are you sure?
Obviously I'm not sure.. it's a vague memory of an interview I can't find (like most information we get out of SpaceX).
no worries... we also kinda mixed the discussion about Dragon and fuel-tank manufacturing, and I don't think they are the same.
I need to get a factory tour...
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The only stir welding process that I know of is good for attaching flat sheets to each other, to make a "bigger" sheet.
It's a really impressive process, but I am not sure how it can be applied to attaching a rib to a flat sheet.
http://www.niar.twsu.edu/researchlabs/ajt_presentations/05-01-06%20Paper-Tweedy%20AIAA%2006-Static%20Strength%20Comparison.pdf
This article has one example.
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The only stir welding process that I know of is good for attaching flat sheets to each other, to make a "bigger" sheet.
It's a really impressive process, but I am not sure how it can be applied to attaching a rib to a flat sheet.
http://www.niar.twsu.edu/researchlabs/ajt_presentations/05-01-06%20Paper-Tweedy%20AIAA%2006-Static%20Strength%20Comparison.pdf
This article has one example.
Thanks - interesting.
Figure 1 shows the butt joint I'm familiar with. The rotating motion of the pin mixes material from both sheets, so the joint (seam) area (shown in Red) has a nice transition into the undisturbed material.
Figure 2 shows the stiffener, but now the mixing of the material has to happen perpendicular to the sheet plane (parallel the pin axis).
Obviously (from the PDF) it works, though the alloy mixing in the weld zone must be pretty sensitive to process parameters. (The sheet alloy wants to stay at the bottom and the stiffener allow wants to stay at the top)
For better or for worse, it will create a more aggressive mixture than the equivalent spot (roll) welding line (where practically no mixing occurs) and the transition in the planar direction will be smoother.
Anyway, thanks - that answers my question wrt to the tank construction.
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I add pictures:
-FSW machine welding the stringers in a RP1 tank barrel
-Rolled panels for Dragon walls
-Jurvetson pic inside Dragon, machining clearly visible on panels.
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The friction stir welding for the tanks was one of the first things they developed for Falcon 5/9. I remember seeing the rig for joining the barrel segments (they called it the "stargate") back in 2006, before the COTS award.
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how does stir-welding a rib onto a sheet work? I can't see the geometry in my head.
Here's another example, a patent
edit: switched link to google patents, much more links to other similar patents there.
http://www.google.com/patents/US8100316?dq=8100316&hl=fi&sa=X&ei=MgYiUfmaFKqp4gSMkoDoDw&ved=0CDYQ6AEwAA (http://www.google.com/patents/US8100316?dq=8100316&hl=fi&sa=X&ei=MgYiUfmaFKqp4gSMkoDoDw&ved=0CDYQ6AEwAA)
(http://www.strutpatent.com/image/get/2012/170/US08100316-20120124-D00000.jpg)
note how that does butt and rib weld in one pass, nice. Another pic
(http://www.strutpatent.com/image/get/2012/US08100316-20120124-D00002.jpg)
edit2: nice ESAB brochure on FSW, on page 18 you see just rib welded (T-joint). Looks like two passes on each side at 45 degrees, just like you'd do using MIG etc.
http://www.esab.ch/de/de/support/upload/FSW-Technical-Handbook.pdf (http://www.esab.ch/de/de/support/upload/FSW-Technical-Handbook.pdf)
edit3: man google popped up a lot of stuff...
http://www.fswelding.com/application-of-friction-stir-welding-in-aircraft-structures/fsw-application (http://www.fswelding.com/application-of-friction-stir-welding-in-aircraft-structures/fsw-application)
(http://www.fswelding.com/_/rsrc/1244623877124/application-of-friction-stir-welding-in-aircraft-structures/fsw-application/aa.JPG?height=167&width=420)
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I'd be willing to bet SuperDraco is regen. It certainly isn't ablative, though I suppose it could be film-cooled. Either way, it reaches steady-state very quickly (within a few seconds) and could as well be fired for minutes as seconds. (Of course, qualifying the engine for longer would be necessary, but I see nothing fundamentally different.)
Agree it's unlikely ablative, but what makes you think it's regen? Or could fire for minues?
Because non-ablative rocket engines reach equilibrium very quickly. It sure as hell isn't a heat-sink engine.
The only other option is film cooling, which for our purposes is very similar (though lower Isp).
I would not be surprised if SuperDraco is ablative, or even Merlin-1A style hybrid. See the test videos. Something that looks like a propellant hose goes to the throat. Inside of nozzle glows very bright.
edit: in the test video the convergent-divergent part appears to be bolted to the rest of the reaction chamber with very sturdy flange. Not very regen like setup.
edit2: why can't a SpaceX rep just say what the deal is, not as if it's a state secret. I know you are watching...
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-Jurvetson pic inside Dragon, machining clearly visible on panels.
Looks like the panels are cast first, then machined to proper tolerance. Milling marks near rib vertices are not uniform.
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They might already have their crew selected
I believe that NASA's AO signed off on their ground test article. As soon as that happened, I'd wire it up to one of Hawthorne's spare MCC rooms so they can start doing ground sims of complete missions for crew candidates.
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-Jurvetson pic inside Dragon, machining clearly visible on panels.
Looks like the panels are cast first, then machined to proper tolerance. Milling marks near rib vertices are not uniform.
Casting thin panels like these isn't easy not cheap, also normally cold rolled material is stronger. In my experience panels like these aren't cast.
Milling marks change is due to the fact that at corners the cutting behaviour of the end mill changes completely.
Edit:spelling
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Casting thin panels like these isn't easy not cheap, also normally cold rolled material is stronger. In my experience panels like these aren't cast.
Milling marks change is due to the fact that at corners the cutting behaviour of the end mill changes completely.
I concur with all, but the corners seem weird for just being milled, would like to know what causes the nonuniform discoloring. See attached close-up. Looks like the mill didn't cut in corners at all, and the top of ribs and vertexes look matte. The corners also have nonuniform areas that look matte as if not cut. Would be bending cause this? Seen old document where plate is first milled to create the ribs, then filled again with another material before bending. Then the filler is removed (solvent, melted?).
edit: here's link to the document
http://www.isogrid-sst.com/Scan%20to%20PDF/Isogrid%20Structures%20Applications.pdf (http://www.isogrid-sst.com/Scan%20to%20PDF/Isogrid%20Structures%20Applications.pdf)
edit2: Compare to Delta IV PLF, everything is very shiny
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I wouldn't doubt at all that it's from some post-machining finishing operation. Post-machining, there are probably a bunch of metal burs that need to be sanded out.
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Could it be some kind of acoustic absorbing/dampening structure?
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@Robotbeat
Machining aluminium with modern, sharp tools, you have very few burrs; I guess SpaceX tries to avoid manual sanding or deburring, it's really time consuming.
@R7
Finish has a price. The Delta IV fairing isogrid seems denser (and any "node" has a hole to make it lighter); I guess machining time was much more in that piece.
To explain what happens, consider the end mill in the picture above: if feed is homogeneous the cutting edge takes a defined chip of material and makes a sharp cut in the metal, leaving a shiny surface; when the mill arrives at the corner, feed is slowed, mill RPM tipically not, you possibly go outside the clean cutting parameters and you have a microscopically torn surface (or small and very messy chips rubbing all around).
Look at the detail you singled; cutting around the circular elevations (change in direction) the finish goes matt.
Can't detail cutting parameters and feed on a single picture (speculation has limits!), but in my experience the different appearance is only a bad visual finish.
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casting is wrong here. Cold rolled, and milled. (Rolling creates superior material, casting is unpredictable, gotta look for flaws, etc)
The corner marks are there since the small-radius fillets are created with a smaller diameter tool than the one used to hog out the triangles.
In this context, btw, machining is not expensive. And obviously cost of material is insignificant. (I have an almost identical flat panel sitting next to me here... and our machinist did a better job with the corner radii....)
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casting is wrong here. Cold rolled, and milled. (Rolling creates superior material, casting is unpredictable, gotta look for flaws, etc)
The corner marks are there since the small-radius fillets are created with a smaller diameter tool than the one used to hog out the triangles.
Makes sense, that's why said in the original post that it "looks" casted ;) because it does, seen alu-cast equipment boxes (but nothing remotely aerospace related) with milled finish surfaces while corners left untouched look just like that.
Some soft-alloy fast milling tools look more like wood-drills, very aggressive flutes, I guess those are used for fast-cutting most material, and smaller more precise tools to finish corners as u said.
Still leaves me a bit curious that the corners don't look the same, one would expect that from CNC machines with accuracy down to thou and less. Maybe SpaceX went even more anal and really had an intern to go through all the corners with dremel like Robotbeat suggested. Some triangles behind Jurvetson's back look like no touch-up at all.
Just overall curiosity how these things are made, wonder if these panels require the "filler" for bending, or is that just for isogrids with more complex, taller ribs.
PS while hunting for isogrid info came across patents that do reference casted isogrid mfg, but those are probably used for smaller pieces and harder materials (stainless, titanium?) that are PITA to machine.
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Thanks for all this info guys, very educational.
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I was wondering, SpaceX tested the Dragon shape for aerodynamics with the first Falcon 9 flight. Might SpaceX try out the Super Draco housings on a upcoming cargo flight for aerodynamics as well? If I remember right the cargo capsule follows almost the same line as the manned Dragon capsule.
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from a SpaceXer yesterday:
"The production floor went from artisan hobbycraft to Real Goddamn Factory in like 3 months."
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from a SpaceXer yesterday:
"The production floor went from artisan hobbycraft to Real Goddamn Factory in like 3 months."
That strongly suggests a serious production rate ramp-up, which is necessary if there is to be any hope of them meeting their manifested flight rate for this year.
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from a SpaceXer yesterday:
"The production floor went from artisan hobbycraft to Real Goddamn Factory in like 3 months."
Anyone have any recent pictures? Before and after would be interesting.
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Processing pictures for upcoming (post-v1.0) CRS flights are probably the best we'll get, but I can't recall seeing any too recently.
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@Robotbeat
Machining aluminium with modern, sharp tools, you have very few burrs; I guess SpaceX tries to avoid manual sanding or deburring, it's really time consuming.
@R7
Finish has a price. The Delta IV fairing isogrid seems denser (and any "node" has a hole to make it lighter); I guess machining time was much more in that piece.
To explain what happens, consider the end mill in the picture above: if feed is homogeneous the cutting edge takes a defined chip of material and makes a sharp cut in the metal, leaving a shiny surface; when the mill arrives at the corner, feed is slowed, mill RPM tipically not, you possibly go outside the clean cutting parameters and you have a microscopically torn surface (or small and very messy chips rubbing all around).
Look at the detail you singled; cutting around the circular elevations (change in direction) the finish goes matt.
Can't detail cutting parameters and feed on a single picture (speculation has limits!), but in my experience the different appearance is only a bad visual finish.
The bulk acerage of the hogged out area is cut with a flat bottom bit for speed, and the corners have to be cut with a radius cutter, possibly even a ball end mill bit to form the fillets at the base of the ribs especially around the lugs. This requires a tool change, and a slightly worn tool (as you might get from the extremely agressive and rapid cutting often used for hog out panels like this) sometimes results in steps and tracks where the cutters transition. And the surface finish on surfaces machined with a ball end mill is usually not as good as for flat bits. The differently colored patches are most likely areas where slight manual touch up was required to meet the drawing's surface finish requirements. If they were due to machining parameter differences, you would expect them to be much more uniform and repeatable corner to corner. Don't forget this engineering unit was one of the first, if not the first, set of such panels SpaceX built.
[edited spelling mistake]
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@blazotron:
thanks for the details.
Many of the things you say are options I considered (not posted, because as I said, speculation has limits); I was (quite) sure the panels weren't castings.
Honestly the only thing I really missed is:
"this engineering unit was one of the first, if not the first, set of such panels SpaceX built"
Otherwise working with a worn tool and being forced to do manual touch is a serious mistake in modern manufacturing.
About machining speed, for people that never saw it, enjoy the video:
https://www.youtube.com/watch?v=JCzFqRU94qE (https://www.youtube.com/watch?v=JCzFqRU94qE)
For people in the known, this is high speed machining (air cooling is the revealing detail) but on aluminium traditional milling parameters aren't that different.
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Senators McCain and Graham visit SpaceX:
https://twitter.com/SpaceX/status/305018927396827137/photo/1
It's important for SpaceX to get bipartisan support. I am glad to see that SpaceX understands that.
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Senators McCain and Graham visit SpaceX:
https://twitter.com/SpaceX/status/305018927396827137/photo/1
It's important for SpaceX to get bipartisan support. I am glad to see that SpaceX understands that.
Now that's a picture I like to see! Good to see SpaceX getting support from the other side of the isle as well. They need all the support they can get and maybe now the program won't be seen as a Democrat fixture. Good for Elon.
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Also, the other side of the aisle needs to be seen in support of SpaceX (and others involved in opening up space to something more closely approximating a free market). They are Republicans, how could they let Obama out-Republican them?
I like McCain, by the by (voted for him). Rohrabacher (sp?) has been also very supportive of SpaceX. It is really a shame, actually, that SpaceX almost became a casualty of the election where people were targeting everything that had any connection with Obama no matter how tenuous (such as executing competitively bid fixed price contracts when he happened to be in office) as "Solyndra."
Good for McCain.
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Suggestions for the CRS-2/SpX-2 Party Thread title please folks.
Obviously I don't want to derail this thread into 50 pages of that, so suggestions only for the next eight hours.
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"Junk in the Trunk Party Thread"?
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"Junk in the Trunk Party Thread"?
We have a winner!
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"Junk in the Trunk Party Thread"?
HA! Wow, we caught fire earlier than expected there. ;D
That's full of win and I'll set it up with that title when I'm back home later on Sunday.
Suggestions: CLOSED!
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Senators McCain and Graham visit SpaceX:
https://twitter.com/SpaceX/status/305018927396827137/photo/1 (https://twitter.com/SpaceX/status/305018927396827137/photo/1)
It's important for SpaceX to get bipartisan support. I am glad to see that SpaceX understands that.
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Party thread for CRS-2 now live.
http://forum.nasaspaceflight.com/index.php?topic=31195.0
I know a few posters on this thread will feel right at home in there! :D
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From the new hot-fire video, before and after:
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From the new hot-fire video, before and after:
Looks like the right hand image is from a previous flight, before some pad updates.
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Interesting... I guess that is what padrat referred to earlier as mods to prepare for F9 v1.1. (and maybe FH as well)
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^ that's what I was thinking.
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New holes in the pad surface are approximately same spot and dimensions to those just built at SLC-4E The part inside the TEL tracks is next to be removed for new SLC-4E based TEL hydraulic lifting device. It is confirmed that F9 and FH will use same HIF.
The mystery is, why would they need the hydraulic lifting device for a FH sized TEL (transporter/erector/launcher), if FH can not be launched from this pad at this orientation?
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New holes in the pad surface are approximately same spot and dimensions to those just built at SLC-4E The part inside the TEL tracks is next to be removed for new SLC-4E based TEL hydraulic lifting device. It is confirmed that F9 and FH will use same HIF.
The mystery is, why would they need the hydraulic lifting device for a FH sized TEL (transporter/erector/launcher), if FH can not be launched from this pad at this orientation?
look here: http://forum.nasaspaceflight.com/index.php?topic=24711.msg1012026#msg1012026 (http://forum.nasaspaceflight.com/index.php?topic=24711.msg1012026#msg1012026)
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russianhalo117, the VAFB building is larger than the CCAFS building.
Are you speculating or do you have a source?
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New holes in the pad surface are approximately same spot and dimensions to those just built at SLC-4E The part inside the TEL tracks is next to be removed for new SLC-4E based TEL hydraulic lifting device. It is confirmed that F9 and FH will use same HIF.
The mystery is, why would they need the hydraulic lifting device for a FH sized TEL (transporter/erector/launcher), if FH can not be launched from this pad at this orientation?
It's always been assumed (because of something Elon once said) that they'd use the existing second firing hole (if that's the right terminology) for the FH. That's immediately north of where F9 launches. But what if instead they widened the hole they currently use east-west and didn't use the second hole at all. Is there any reason they couldn't do that? The flame / smoke duct points just south of east.
http://wikimapia.org/#lat=28.5619799&lon=-80.5770973&z=20&l=0&m=b (http://wikimapia.org/#lat=28.5619799&lon=-80.5770973&z=20&l=0&m=b)
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New holes in the pad surface are approximately same spot and dimensions to those just built at SLC-4E The part inside the TEL tracks is next to be removed for new SLC-4E based TEL hydraulic lifting device. It is confirmed that F9 and FH will use same HIF.
The mystery is, why would they need the hydraulic lifting device for a FH sized TEL (transporter/erector/launcher), if FH can not be launched from this pad at this orientation?
look here: http://forum.nasaspaceflight.com/index.php?topic=24711.msg1012026#msg1012026 (http://forum.nasaspaceflight.com/index.php?topic=24711.msg1012026#msg1012026)
I tend to agree with you, it seems reasonable that the new "holes" are for hydraulic devices like that at SLC-4E, but why? Does the taller F9 1.1 and its TEL really need an all new lifting mechanism?
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New holes in the pad surface are approximately same spot and dimensions to those just built at SLC-4E The part inside the TEL tracks is next to be removed for new SLC-4E based TEL hydraulic lifting device. It is confirmed that F9 and FH will use same HIF.
The mystery is, why would they need the hydraulic lifting device for a FH sized TEL (transporter/erector/launcher), if FH can not be launched from this pad at this orientation?
look here: http://forum.nasaspaceflight.com/index.php?topic=24711.msg1012026#msg1012026 (http://forum.nasaspaceflight.com/index.php?topic=24711.msg1012026#msg1012026)
I tend to agree with you, it seems reasonable that the new "holes" are for hydraulic devices like that at SLC-4E, but why? Does the taller F9 1.1 and its TEL really need an all new lifting mechanism?
FH does to handle the higher launcher mass.
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russianhalo117, the VAFB building is larger than the CCAFS building.
Are you speculating or do you have a source?
Well the width looks the same. I have no clue what the actual dimensions are since I cannot not measure it and I have not seen them posted anywhere on an official site.
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russianhalo117, the VAFB building is larger than the CCAFS building.
Are you speculating or do you have a source?
Well the width looks the same. I have no clue what the actual dimensions are since I cannot not measure it and I have not seen them posted anywhere on an official site.
There is a thread that shows that the existing CCAFS hangar is too small for the heavy. Anyways, a new one can be used since the heavy TEL doesn't use rails
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Post of the Photoshop is:
http://forum.nasaspaceflight.com/index.php?topic=21873.msg674675#msg674675
Pic below.
(Original post & Photoshop by gospacex, not mine)
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russianhalo117, the VAFB building is larger than the CCAFS building.
Are you speculating or do you have a source?
Well the width looks the same. I have no clue what the actual dimensions are since I cannot not measure it and I have not seen them posted anywhere on an official site.
There is a thread that shows that the existing CCAFS hangar is too small for the heavy. Anyways, a new one can be used since the heavy TEL doesn't use rails
I've wondered for a while if SpaceX are going to build a clone of the SLC-4 facility at CCAFS and use the existing HIF as a shed for a swing-up mobile Vertical Servicing Structure.
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Biggest issue with the above pics....the extra exhaust port, which is currently covered with a steel plate, is to the north of the currently used port. So your orientation is wrong, which is prob why they were looking at the option of building a new hanger at a right angle to the current one. However, looking at that pic, it would be tight and involve moving some structure but it would prob fit....
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Still no Falcon 9 v1.1 unveiling.
I'm feeling confident of my 1 launch prediction. :)
The rocket exists but I'm speculating there's a long way to go before the VAFB pad is ready to launch it.
And I'll put money down that you'll be wrong. ;D
I wonder if CCAFS might be ready before VAFB. What's the bet that the first F9 v.1.1 is on the East Range, maybe an Orbcomm cluster?
Brought this over from the number of flights poll 2013 so as not to upset the sheriff.
SpaceX had this to say on on page 18 of the CRS 2 press kit.
Quote: SpaceX is developing a new launch pad at Vandenberg Air Force Base. It is on target for activation in 2013
spectre9 why the doubt?
Perhaps padrat has some more insight.
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Biggest issue with the above pics....the extra exhaust port, which is currently covered with a steel plate, is to the north of the currently used port. So your orientation is wrong, which is prob why they were looking at the option of building a new hanger at a right angle to the current one. However, looking at that pic, it would be tight and involve moving some structure but it would prob fit....
I would have expected you to object to the lack of working space inside the hangar that I would see as the major challenge there. The door may be wide enough but can you maneuver various parts around inside to realistically, safely and securely (and preferably efficiently) undertake commissioning?
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spectre9 why the doubt?
Schedule slips are par for course with SpaceX. The first Vandenberg launch has slipped to around June and, if it's the first F9 v.1.1 flight, then the time-line for the rest of this year's manifest gets very tight.
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There are only 3 flights on the manifest out of Vandenberg in 2013
2 F9
1 FH
Takeaway the FH and two flights seems doable even if the first is delayed until June.
CCAFS has 4 flights of F9 manifested.
Even with the SpaceX time dilation factor, which I think is over stated by many, 1 SpaceX flight in 2013, as predicted by spectre9 seems incredibly pessimistic especially given that there will more than likely be one flight later this week.
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There are only 3 flights on the manifest out of Vandenberg in 2013
2 F9
1 FH
Takeaway the FH and two flights seems doable even if the first is delayed until June.
CCAFS has 4 flights of F9 manifested.
Even with the SpaceX time dilation factor, which I think is over stated by many, 1 SpaceX flight in 2013, as predicted by spectre9 seems incredibly pessimistic especially given that there will more than likely be one flight later this week.
Agreed, but then again, I've noticed that Spectre9 isn't the biggest SpaceX fan under the sun :)
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I've wondered for a while if SpaceX are going to build a clone of the SLC-4 facility at CCAFS and use the existing HIF as a shed for a swing-up mobile Vertical Servicing Structure.
I assume you mean at SLC-40. It's certainly a possibility, but it may be difficult to do without affecting the operation of the present pad. A new site might be preferable.
There is no need for the extra complication of a swing up service tower. It doesn't have to be kept in a hangar. It's easier to build a free standing structure which moves on rails in the traditional way.
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Anybody watching the streaming conference at http://www.spaceflightnow.com/falcon9/005/status.html (http://www.spaceflightnow.com/falcon9/005/status.html)?
Gwen just announced that "a materials defect" in the "engine bell" was the cause of the engine anomaly on CRS1.
Lot's of good information in this brief.
They're taking questions now.
Apologies if this is already on a different thread.
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Am I right in thinking that SpaceX's CRS contract is for the total of upmass payload and downmass payload to add up to 20 tonnes?
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Am I right in thinking that SpaceX's CRS contract is for the total of upmass payload and downmass payload to add up to 20 tonnes?
That's what Gwen just said on the briefing. And that Spacex would "far exceed that" in it's 12 resupply flights.
She also noted that this flight was "near the max payload mass" for launch.
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From update thread:
Gwen doesn't really want to talk about the loss of one flight computer on CRS-1. Radiation tolerant, but can have faults. Doesn't want to say why they decided not to re-sync the computer.
Makes sense, the only thing they could say might be miss-perceived as a statement showing friction between SpaceX and NASA. Best not to talk about it.
The story is that SpaceX designed the flight computer system with 3 independent computation streams, and the plan was that when one is knocked out it would be reset and get back in the game. But the resetting on orbit (while attached to ISS) hadn't been done before and had to be triggered from the ground. NASA's well placed conservatism led to uneasiness with attempting the reset, and SpaceX read the mood and didn't want to push things.
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Gwen says the engine failure of CRS-1 was due to a material flaw in the jacket of the engine.
What does that mean?
I tried to remember her exact words.
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Gwen says she thinks the mass that this Falcon V1.0 CRS-2 is launching is pretty close to being maxed out. But she is not sure.
Does this indicate the maximum mass of payload of the F9 V1.0?
Grapple bars are 273kg. Fixed clips are ~100kg and don't leave the trunk.
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Gwen says the engine failure of CRS-1 was due to a material flaw in the jacket of the engine.
What does that mean?
I tried to remember her exact words.
Poor quality metal, impurities in the alloy or something. What matters is that it wasn't able to handle the forces of the engine operating and the combustion chamber ruptured.
What I find interesting is that the State Department is 'investigating' and that there are ITAR 'issues'. That suggests maybe raw materials imported from overseas with misleading/inaccurate descriptions, maybe even faked government inspection certificates from the country of origin.
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Gwen says the engine failure of CRS-1 was due to a material flaw in the jacket of the engine.
What does that mean?
I tried to remember her exact words.
Poor quality metal, impurities in the alloy or something. What matters is that it wasn't able to handle the forces of the engine operating and the combustion chamber ruptured.
What I find interesting is that the State Department is 'investigating' and that there are ITAR 'issues'. That suggests maybe raw materials imported from overseas with misleading/inaccurate descriptions, maybe even faked government inspection certificates from the country of origin.
The jacket: is it some sort of heat resistant coating on the inside surface of the pressure dome?
I think the ITAR comment was her not wanting to go into to much detail in case she accedentally hand over US space technology to overseas interests. She later said she doesn't want to be in horizontal stripes...
....jail. :-)
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The jacket: is it some sort of heat resistant coating on the inside surface of the pressure dome?
No, it's the actual metal (likely a laminate of many different alloys) that make up the physical structure of the dome.
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What I find interesting is that the State Department is 'investigating' and that there are ITAR 'issues'. That suggests maybe raw materials imported from overseas with misleading/inaccurate descriptions, maybe even faked government inspection certificates from the country of origin.
The State Dept isn't investigating, they are reviewing the report on the anomaly from the Spacex/NASA investigation, to make sure it doesn't contain any ITAR sensitive information before it is released publicly.
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Grapple bars are 273kg. Fixed clips are ~100kg and don't leave the trunk.
Grapple bars, NASA hardware and the hardware to attach the grapple bars to station, which was made by SpaceX mass ~373kg.
There is also the mounting hardware that holds these two pieces in the trunk, which stays in the trunk, their mass was not mentioned.
This means SpaceX will have hardware on station after Dragon departure.
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Gwen says the engine failure of CRS-1 was due to a material flaw in the jacket of the engine.
What does that mean?
I tried to remember her exact words.
The Merlin 1c combustion chamber and throat is made of copper. Grooves for fuel (i.e. coolant) are milled into the outside of this copper vessel. A stainless steel "jacket" is brazed to the outside of the copper inner chamber, forming the the channels which fuel passes through on its way to the injector. The jacket is formed in a process that Musk has described as "electroplated layer by layer". If the "jacket" was indeed the engine component that failed on CRS-1, then the "sudden pressure loss" was caused by a high pressure fuel leak, presumably at or near the "fuel dome" (the top of the combustion chamber), NOT by a rupture of the combustion chamber itself, nor was the "pressure loss" caused by escaping combustion gasses.
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Grapple bars are 273kg. Fixed clips are ~100kg and don't leave the trunk.
Grapple bars, NASA hardware and the hardware to attach the grapple bars to station, which was made by SpaceX mass ~373kg.
There is also the mounting hardware that holds these two pieces in the trunk, which stays in the trunk, their mass was not mentioned.
This means SpaceX will have hardware on station after Dragon departure.
Later in the interview she gave the 373kg total. But earlier she said 273kg including SpaceX designed brackets that will go into the space station and be used to store the grapple bars in the station. She was proud of SpaceX hardware becoming part of the ISS.
She said on top of this was ~100kg for brackets to mount the grapple bars in the trunk during the launch. These brackets remain in the trunk.
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Gwen says the engine failure of CRS-1 was due to a material flaw in the jacket of the engine.
What does that mean?
I tried to remember her exact words.
The Merlin 1c combustion chamber and throat is made of copper. Grooves for fuel (i.e. coolant) are milled into the outside of this copper vessel. A stainless steel "jacket" is brazed to the outside of the copper inner chamber, forming the the channels which fuel passes through on its way to the injector. The jacket is formed in a process that Musk has described as "electroplated layer by layer". If the "jacket" was indeed the engine component that failed on CRS-1, then the "sudden pressure loss" was caused by a high pressure fuel leak, presumably at or near the "fuel dome" (the top of the combustion chamber), NOT by a rupture of the combustion chamber itself, nor was the "pressure loss" caused by escaping combustion gasses.
She definitely said material flaw of the jacket. She sound confident in saying it. But it could still be the most 'likely' cause from the information that they have. The report is currently being reviewed before detailed info is released to public. Partly to ensure ITAR sensitive info is protected.
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Gwen says the engine failure of CRS-1 was due to a material flaw in the jacket of the engine.
What does that mean?
I tried to remember her exact words.
The Merlin 1c combustion chamber and throat is made of copper. Grooves for fuel (i.e. coolant) are milled into the outside of this copper vessel. A stainless steel "jacket" is brazed to the outside of the copper inner chamber, forming the the channels which fuel passes through on its way to the injector. The jacket is formed in a process that Musk has described as "electroplated layer by layer". If the "jacket" was indeed the engine component that failed on CRS-1, then the "sudden pressure loss" was caused by a high pressure fuel leak, presumably at or near the "fuel dome" (the top of the combustion chamber), NOT by a rupture of the combustion chamber itself, nor was the "pressure loss" caused by escaping combustion gasses.
thanks corrodedNut, best description yet much appreciated.
PS I keep wanting to call you rusty balls........just kidding ;D
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Gwen says the engine failure of CRS-1 was due to a material flaw in the jacket of the engine.
What does that mean?
I tried to remember her exact words.
The Merlin 1c combustion chamber and throat is made of copper. Grooves for fuel (i.e. coolant) are milled into the outside of this copper vessel. A stainless steel "jacket" is brazed to the outside of the copper inner chamber, forming the the channels which fuel passes through on its way to the injector. The jacket is formed in a process that Musk has described as "electroplated layer by layer". If the "jacket" was indeed the engine component that failed on CRS-1, then the "sudden pressure loss" was caused by a high pressure fuel leak, presumably at or near the "fuel dome" (the top of the combustion chamber), NOT by a rupture of the combustion chamber itself, nor was the "pressure loss" caused by escaping combustion gasses.
Thanks for that.
I'm guessing there are many parallel channels? (or else the flow in the channels is needlessly fast)
If I understand the structure correctly, then if the failure occurred before the fuel dome (from the fuel's perspective) then there's a natural limit to how much fuel can be released, even if the turbo pump is not shut down immediately. (If it was the dome itself, then it can be argued that the still running turbo pump makes the failure closer to the case of a gas container bursting, since there's a bit of an effective "pressure reservoir".)
Does anyone know what a typical channel configuration is like? Is it one large spiral? multiple-start spirals? radial lines? In some engines you can see (I think) the spiral on the outside, but those don't fit the copper-stainless sandwich description of this engine.
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Does anyone know what a typical channel configuration is like? Is it one large spiral? multiple-start spirals? radial lines? In some engines you can see (I think) the spiral on the outside, but those don't fit the copper-stainless sandwich description of this engine.
Depends on M1D (http://www.flickr.com/photos/jurvetson/8233308933/) or M1C (http://www.flickr.com/photos/jurvetson/4928541992/) (thumbnails attached); for M1d:
A separate building contains the manufacturing flow for the Merlin 1D engines. The shiny nozzle here has channels etched vertically in it for the fuel to run down and back up, keeping the nozzle from melting during use. The nozzles at the far end of the room have those channels and are ready for a metal jacket to cover them. This is much more elegant than the individual brazed tubes used in the earlier Merlin engines, or the RL-10 used on other rockets.
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Does anyone know what a typical channel configuration is like? Is it one large spiral? multiple-start spirals? radial lines? In some engines you can see (I think) the spiral on the outside, but those don't fit the copper-stainless sandwich description of this engine.
Depends on M1D (http://www.flickr.com/photos/jurvetson/8233308933/) or M1C (http://www.flickr.com/photos/jurvetson/4928541992/) (thumbnails attached); for M1d:
A separate building contains the manufacturing flow for the Merlin 1D engines. The shiny nozzle here has channels etched vertically in it for the fuel to run down and back up, keeping the nozzle from melting during use. The nozzles at the far end of the room have those channels and are ready for a metal jacket to cover them. This is much more elegant than the individual brazed tubes used in the earlier Merlin engines, or the RL-10 used on other rockets.
Very good then. A radial configuration is the best at limiting the released flow in a event like this. (if indeed it was in the jacket and not the dome)
Electroforming and brazing. Processes I like.
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What is this?
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I would guess a lox vent. It kept venting after shutdown.
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What is this?
Likely a interseal purge dump line for the turbopump
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What is this?
The black spot to the left of the bell in the image.. was that a camera drop out? At first I thought it was S1 but it didn't recede (didn't change position, didn't get smaller) so ??
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What is this?
The black spot to the left of the bell in the image.. was that a camera drop out? At first I thought it was S1 but it didn't recede (didn't change position, didn't get smaller) so ??
Dirt on the camera cover, duh ;)
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What is this?
The black spot to the left of the bell in the image.. was that a camera drop out? At first I thought it was S1 but it didn't recede (didn't change position, didn't get smaller) so ??
It was a UFO trailing the vehicle
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It was a UFO trailing the vehicle
LOL! :D
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What is this?
The black spot to the left of the bell in the image.. was that a camera drop out? At first I thought it was S1 but it didn't recede (didn't change position, didn't get smaller) so ??
Dirt on the camera cover, duh ;)
Sorry, I like Jim's answer better. Besides why would there be dirt? Wouldn't they tend to clean that sort of thing as part of prelaunch procedures?
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What is this?
The black spot to the left of the bell in the image.. was that a camera drop out? At first I thought it was S1 but it didn't recede (didn't change position, didn't get smaller) so ??
It was a UFO trailing the vehicle
I see that Jim does have a sense of humor!
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AS-503, you really think Jim was joking?
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Those darn aliens mess up everything. Guess its not the first time I suppose.
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AS-503, you really think Jim was joking?
Thats funny, the moment I posted my humor comment I got the feeling that Jim was not joking.
Its that bad association of UFO meaning something alein, instead of the literal translation.
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How do you know the aliens are not from the future and just trying to observe what went wrong so they don't repeat the issue thruster issue on CRS-3.
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Interesting: Musks just said that the crewed Dragon that goes to the ISS wont have solar arrays, but a bigger battery instead. There will still be solar arrays for long duration missions. Wonder what else will be different...
I guess the battery will be in the reuseable part of the dragon?
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Interesting: Musks just said that the crewed Dragon that goes to the ISS wont have solar arrays, but a bigger battery instead. There will still be solar arrays for long duration missions. Wonder what else will be different...
I guess the battery will be in the reuseable part of the dragon?
IIRC it was mentioned the panels cost upwards of several millions $.
Good idea to reuse that.
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Interesting: Musks just said that the crewed Dragon that goes to the ISS wont have solar arrays, but a bigger battery instead. There will still be solar arrays for long duration missions. Wonder what else will be different...
I guess the battery will be in the reuseable part of the dragon?
Personally, I think that today's issue may lead the guys in the Dragonrider design office sit down and at least recheck their math on that one.
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One of the shots I got from Kennedy Point Park of the launch before she went into the cloud layers.
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IIRC it was mentioned the panels cost upwards of several millions $.
Good idea to reuse that.
Wow, if that is true that certainly sounds quite expensive, especially considering the cost of the rest of the vehicle/launch. Normally the cost of a solar panel is about 1000 USD per KW. Granted, these solar arrays are not your usual rooftop kind, but that still seems pretty harsh. It would certainly make sense to replace them with batteries in that case. Why not do the same for cargo?
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IIRC it was mentioned the panels cost upwards of several millions $.
Good idea to reuse that.
Wow, if that is true that certainly sounds quite expensive, especially considering the cost of the rest of the vehicle/launch. Normally the cost of a solar panel is about 1000 USD per KW. Granted, these solar arrays are not your usual rooftop kind, but that still seems pretty harsh. It would certainly make sense to replace them with batteries in that case. Why not do the same for cargo?
Because by policy, ISS will not perform reboosts to adjust phasing for cargo flights. So early rendezvous will not always be possible.
But if they extent the battery capacity enough (as Musk said they would for the crew version), would they need to do an early rendezvous?
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IIRC it was mentioned the panels cost upwards of several millions $.
Good idea to reuse that.
Wow, if that is true that certainly sounds quite expensive, especially considering the cost of the rest of the vehicle/launch. Normally the cost of a solar panel is about 1000 USD per KW. Granted, these solar arrays are not your usual rooftop kind, but that still seems pretty harsh. It would certainly make sense to replace them with batteries in that case. Why not do the same for cargo?
Because by policy, ISS will not perform reboosts to adjust phasing for cargo flights. So early rendezvous will not always be possible.
But if they extent the battery capacity enough (as Musk said they would for the crew version), would they need to do an early rendezvous?
There can be batteries in two places. In the trunk for the mission and Dragon for entry
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IIRC it was mentioned the panels cost upwards of several millions $.
Good idea to reuse that.
Wow, if that is true that certainly sounds quite expensive, especially considering the cost of the rest of the vehicle/launch. Normally the cost of a solar panel is about 1000 USD per KW. Granted, these solar arrays are not your usual rooftop kind, but that still seems pretty harsh. It would certainly make sense to replace them with batteries in that case. Why not do the same for cargo?
Because by policy, ISS will not perform reboosts to adjust phasing for cargo flights. So early rendezvous will not always be possible.
But if they extent the battery capacity enough (as Musk said they would for the crew version), would they need to do an early rendezvous?
There can be batteries in two places. In the trunk for the mission and Dragon for entry
No doubt about that. Wondering whether it will be cheaper though to throw away batteries than to throw away the solar panels. I am still shocked by how much more expensive Dragons solar arrays are compared to their non space counterparts. If the same applies to the batteries, throwing them away with the trunk might not save you much money (and I dont have any numbers for that).
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IIRC it was mentioned the panels cost upwards of several millions $.
Good idea to reuse that.
Wow, if that is true that certainly sounds quite expensive, especially considering the cost of the rest of the vehicle/launch. Normally the cost of a solar panel is about 1000 USD per KW. Granted, these solar arrays are not your usual rooftop kind, but that still seems pretty harsh. It would certainly make sense to replace them with batteries in that case. Why not do the same for cargo?
Because by policy, ISS will not perform reboosts to adjust phasing for cargo flights. So early rendezvous will not always be possible.
But if they extent the battery capacity enough (as Musk said they would for the crew version), would they need to do an early rendezvous?
There can be batteries in two places. In the trunk for the mission and Dragon for entry
No doubt about that. Wondering whether it will be cheaper though to throw away batteries than to throw away the solar panels. I am still shocked by how much more expensive Dragons solar arrays are compared to their non space counterparts. If the same applies to the batteries, throwing them away with the trunk might not save you much money (and I dont have any numbers for that).
I hear Boeing is selling battery packs for cheap now. <ducks>
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I hear Boeing is selling battery packs for cheap now. <ducks>
At least those batteries could solve their issues with frozen valves <giggles>
;)
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I wonder if SpaceX is getting help from Boeing to develop their lithium battery-only power system, like CST-100? ;)
(entirely tongue-in-cheek, by the way)
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curious
how would the lack of thruster firing after 2nd stage separation, if the mission required stage 2 to do second burn, how much would that have affected the re-ignition. I am assuming they want both 2nd stage and dragon relatively far apart before restart.
jb
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If the crewed version of Dragon is to have no PVAs, does it still need a trunk?
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If the crewed version of Dragon is to have no PVAs, does it still need a trunk?
IIRC, the trunk also carries the radiators.
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Interesting: Musks just said that the crewed Dragon that goes to the ISS wont have solar arrays, but a bigger battery instead. There will still be solar arrays for long duration missions. Wonder what else will be different...
I guess the battery will be in the reuseable part of the dragon?
IIRC it was mentioned the panels cost upwards of several millions $.
Good idea to reuse that.
Where was that mentioned? If someone is deciding that amount by comparing surface area to panel costs then they are going to get a vastly wrong figure. SpaceX uses dirt cheap silicon cells, not the commonly used BJT cells used on most space solar panels. You get a greatly reduced efficiency, but an even greater reduction in overall cost. It's a mass/power tradeoff.
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IIRC it was mentioned the panels cost upwards of several millions $.
Good idea to reuse that.
Wow, if that is true that certainly sounds quite expensive, especially considering the cost of the rest of the vehicle/launch. Normally the cost of a solar panel is about 1000 USD per KW. Granted, these solar arrays are not your usual rooftop kind, but that still seems pretty harsh. It would certainly make sense to replace them with batteries in that case. Why not do the same for cargo?
Yes they are similar to the standard rooftop kind.
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Watched the launch this morning, very beautiful vid views!!! :D
Congrats to the SpaceX team & NASA for working thru the valve issues!!!
This is all good stuff cause it ultimately gains everyone much needed high stress work experience and more knowledge about the vehicle. ;D
k I have a question about the 2nd stage engine firing, since I'm not an engineer...What is the small valve (looks like a smaller silver engine bell) above the main engine bell, and why does it move quickly to the right every so often? ???
thx!
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Watched the launch this morning, very beautiful vid views!!! :D
Congrats to the SpaceX team & NASA for working thru the valve issues!!!
This is all good stuff cause it ultimately gains everyone much needed high stress work experience and more knowledge about the vehicle. ;D
k I have a question about the 2nd stage engine firing, since I'm not an engineer...What is the small valve (looks like a smaller silver engine bell) above the main engine bell, and why does it move quickly to the right every so often? ???
thx!
It is providing as-needed trim to the ascent trajectory (when it kicks to the right and fires, the vehicle will roll to the left).
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Watched the launch this morning, very beautiful vid views!!! :D
Congrats to the SpaceX team & NASA for working thru the valve issues!!!
This is all good stuff cause it ultimately gains everyone much needed high stress work experience and more knowledge about the vehicle. ;D
k I have a question about the 2nd stage engine firing, since I'm not an engineer...What is the small valve (looks like a smaller silver engine bell) above the main engine bell, and why does it move quickly to the right every so often? ???
thx!
It is providing as-needed trim to the ascent trajectory (when it kicks to the right and fires, the vehicle will roll to the left).
Thx! Kinda was thinking that...just need confirmation.
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Basically just directs gas generator exhaust for roll control, etc.
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BTW, there's a way to avoid single-point-of-failure in your checkvalve: Use four of them, two parallel branches of two check valves in series. It guards against any one check valve failing either on or off. At the expense of more pressure drop, mass, complexity, etc...
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If the crewed version of Dragon is to have no PVAs, does it still need a trunk?
Which brings us full circle to the fact that no one has seen Dragon 2.0 yet so we don't know about the level of changes - we're all just guessing.
D2.0 will still support Solar panels for long duration missions, but that might be an entire hab add-on.
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Interesting: Musks just said that the crewed Dragon that goes to the ISS wont have solar arrays, but a bigger battery instead. There will still be solar arrays for long duration missions. Wonder what else will be different...
I guess the battery will be in the reuseable part of the dragon?
IIRC it was mentioned the panels cost upwards of several millions $.
Good idea to reuse that.
Where was that mentioned? If someone is deciding that amount by comparing surface area to panel costs then they are going to get a vastly wrong figure. SpaceX uses dirt cheap silicon cells, not the commonly used BJT cells used on most space solar panels. You get a greatly reduced efficiency, but an even greater reduction in overall cost. It's a mass/power tradeoff.
Can't remember aside that it was somewhere on these forums.
It was also initially mentioned SpaceX will switch to a different kind of solar panels for the crew version. No luck finding either discussion though.
Do you guys know what Apollo/Shuttle/Soyuz used for power generation? I don't remember seeing panels on any one of those.
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Dirt on the camera cover, duh ;)
But really, this sort of thing happens on every single launch of every single type of rocket - at least those which have onboard cameras - and seeing that footage is one of the main highlights for the viewing public.
Why can't somebody come up with a damn solution to this problem?
It's the same question I ask when I hear about mars rovers being impaired by dust on the solar panels.
Can't somebody come up with some mini-windshield-wipers?
Next thing - regarding the speculation that it was frozen oxidizer which caused problems for the Dragon thrusters, what is the likely future fix to prevent reoccurrence of this problem?
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BTW, there's a way to avoid single-point-of-failure in your checkvalve: Use four of them, two parallel branches of two check valves in series. It guards against any one check valve failing either on or off. At the expense of more pressure drop, mass, complexity, etc...
Like this (1):
__/----(X)----\___/----(X)----\___
\----(X)----/ \----(X)----/
or like this (2)?
__/----(X)--------(X)----\___
\----(X)--------(X)----/
Anyone good with probabilities to discuss the the one with less probability of total failure for all situations?
Edit: I think Robotbeat was talking about #2 but #1 can work in more situations with 3 defective valves.
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Ah, right, I hadn't considered the first one...
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(1)
__/----(X)----\___/----(X)----\___
\----(X)----/ \----(X)----/
(2)
__/----(X)--------(X)----\___
\----(X)--------(X)----/
If each X has a 50% chance of failure, and success is defined as having any path available from left to right...
In (1), 75% of the time you have a way from left to middle, and 75% of the time you have a way from middle to right... so that's 56% of the time you have a way through, which is an improvement of 6% over just one valve.
In (2), the top line fails 75% of the time (success @ 0.5 * 0.5), and the bottom line does the same, so the risk of failure is 56% - six percent worse than a single valve.
In one you're making something redundant, in the other you're making it worse and then slightly redundant.
By the way, two valves next to each other have a 75% chance of success, which is much higher than either of your drawings, which suggests to me that you're drawing the wrong pictures.
(Standard disclaimer: I'm deriving by staring and thinking, and my staring and thinking may be off a bit from the party thread. Feel free to double-check and debunk!)
(Followup disclaimer: turns out this really is rocket science. Thanks RobotBeat and Jorge.)
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Well yeah, if you have a 50% rate of failure, most redundancy schemes are probably going to make things work. Check it for 1% or 0.1% chance of failure.
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Dirt on the camera cover, duh ;)
But really, this sort of thing happens on every single launch of every single type of rocket - at least those which have onboard cameras - and seeing that footage is one of the main highlights for the viewing public.
Why can't somebody come up with a damn solution to this problem?
Formula 1 onboard cameras have some sort of a rotating circular glass in front of the camera. The glass rotates every "x" seconds and dirty/oil is cleaned in the back. It is a simple rotating device that rotates every time to the same side, no aerodynamic issues and no parts to go loose.
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You need to also consider the possibility of a valve failing *open* as well as closed. In other words, don't define "success" as having a path through the system, define "failure" as *either* not having a path through the system when you want it, *or* having a path through the system when you *don't* want it.
Exactly, but it can even get more complex! Let's say that the probability of failure is define by an exponential distribution depending on the number of operations. Using #1 you can start by using just 2 valves and when one fails due to fatigue you can use a fresh one.
So #1 is also better for fatigue malfunctions. On #2, a failure invalidates the other valve in series, which is still working well.
Also #1 scales quite well, the failure probability decreases even further with more parallel valves.
/----(X)---\ /----(X)---\
__/----(X)----\___/----(X)----\___
\----(X)----/ \----(X)----/
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You need to also consider the possibility of a valve failing *open* as well as closed. In other words, don't define "success" as having a path through the system, define "failure" as *either* not having a path through the system when you want it, *or* having a path through the system when you *don't* want it.
Exactly, but it can even get more complex! Let's say that the probability of failure is define by an exponential distribution depending on the number of operations. Using #1 you can start by using just 2 valves and when one fails due to fatigue you can use a fresh one.
So #1 is also better for fatigue malfunctions. On #2, a failure invalidates the other valve in series, which is still working well.
Also #1 scales quite well, the failure probability decreases even further with more parallel valves.
/----(X)---\ /----(X)---\
__/----(X)----\___/----(X)----\___
\----(X)----/ \----(X)----/
Adding more valves in || helps if your failure is "stuck closed", but doesn't help if your failure is "stuck open"... because with a connection in the middle you are really in a bad way if you get a stuck open on both the first and second parts.. so you want to have THREE parralel ladders in series and now you have made the system vastly more complex I fear.
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It also doesn't help if you get FOD between both banks
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Sooo basic put-more-of-them-in-there redundancy is completely useless if stuck-open is a failure mode.
How do you do redundant backups for stuck-open? I guess the serial version ((2)) from the original diagrams?
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Sooo basic put-more-of-them-in-there redundancy is completely useless if stuck-open is a failure mode.
How do you do redundant backups for stuck-open? I guess the serial version ((2)) from the original diagrams?
On the most simplistic view:
The serial version (2) is dual redundant for stuck open but twice as bad for stuck closed.
The mixed version (1) is dual redundant for stuck open and stuck closed.
Complex view:
- stuck closed or open can have different probabilities of occurrence
- stuck closed or open can have different risks. A stuck open valve connecting two tanks might not affect the mission, but a stuck closed might.
For n-level of stuck open redundancy, we can propagate it like this:
/----(X)---\ /----(X)---\ /----(X)---\
__/----(X)----\___/----(X)----\___/----(X)----\___
\----(X)----/ \----(X)----/ \----(X)----/
although in practice this could have some limitations... this was an armchair engineering probability exercise...
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That configuration also gives 3-level redundancy for stuck closed. In general you can achieve n-general redundancy for both stuck open and stuck closed with n^2 valves by propagating n by n valves in the configuration you described.
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Sure, but just as a reminder, all of this works for statistically independent failures, right? If there's humidity in the system and it's too cold, then all of them will fail.
So it makes more sense when you're talking for example about flight computers that are subject to random errors.
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Sure, but just as a reminder, all of this works for statistically independent failures, right? If there's humidity in the system and it's too cold, then all of them will fail.
So it makes more sense when you're talking for example about flight computers that are subject to random errors.
A point that many people miss.
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Sure, but just as a reminder, all of this works for statistically independent failures, right? If there's humidity in the system and it's too cold, then all of them will fail.
So it makes more sense when you're talking for example about flight computers that are subject to random errors.
2x2 or nxn configuration also arguably makes it more difficult to "hammer-head" valves (the thing SpaceX did to solve Spx-2 problems), so the single valve can be the best solution.
After all they could fly on 3 pods out of 4, so keeping each pod system as simple is possible is probably the best idea.
Anyway when 3 of 4 valves fail (or 3 of 8, depending on if it was pure coincidence that all failed valves were on ox lines, not on fuel lines), this means something is really wrong and redundancy would not help such issues.
Edit: the probability that all 3 failed valves are on either ox or fuel system is 1/7.
The first failed valve can by any of 8. The probability of the second failed valve to be on the same subsystem is 3 of remaining 7, and the probability of the third failed valve to be on the same subsystem is 2 of remaining 6, so the result is (3/7)*(2/6)=1/7
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Apollo and shuttle used fuel cells with cryogenic reactants.
Didn't Apollo also use hydrazine fuel cells? Or was that Mercury / Gemini?
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Didn't Apollo also use hydrazine fuel cells? Or was that Mercury / Gemini?
Don't think so. Gemini and Apollo used H2/02 fuel cells. (Some Geminis were battery powered.) Mercury only used batteries.
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Dirt on the camera cover, duh ;)
But really, this sort of thing happens on every single launch of every single type of rocket - at least those which have onboard cameras - and seeing that footage is one of the main highlights for the viewing public.
Why can't somebody come up with a damn solution to this problem?
Formula 1 onboard cameras have some sort of a rotating circular glass in front of the camera. The glass rotates every "x" seconds and dirty/oil is cleaned in the back. It is a simple rotating device that rotates every time to the same side, no aerodynamic issues and no parts to go loose.
I'd think the cleaning system would be complicated and subject to getting gunked up, resulting in smearing.
Actually, it's a simple roll of plastic which is spooled across the lens every few seconds.
Think of it like the film inside an old film camera, but in this case the plastic is a see-through lens cover. The dirty stuff simply winds onto the take-up spool and is not re-used.
It's a simple, low-mass, reliable system, though a little bulky I understand. It also copes OK with 5G+ braking and gets a pretty rough ride via the car's chassis. Whether it could be beefed up to cope with supersonic airflows I have no idea.
cheers, Martin
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BTW, there's a way to avoid single-point-of-failure in your checkvalve: Use four of them, two parallel branches of two check valves in series. It guards against any one check valve failing either on or off. At the expense of more pressure drop, mass, complexity, etc...
ISTR that is a requirement in NASA's Human Rating standards for anything mission critical?
cheers, Martin
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Interesting: Musks just said that the crewed Dragon that goes to the ISS wont have solar arrays, but a bigger battery instead. There will still be solar arrays for long duration missions. Wonder what else will be different...
I guess the battery will be in the reuseable part of the dragon?
Personally, I think that today's issue may lead the guys in the Dragonrider design office sit down and at least recheck their math on that one.
ISTM, the battery (including any redundancy) only needs to last as long as the shortest-lived element of the life-support system.
cheers, Martin
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Interesting: Musks just said that the crewed Dragon that goes to the ISS wont have solar arrays, but a bigger battery instead. There will still be solar arrays for long duration missions. Wonder what else will be different...
I guess the battery will be in the reuseable part of the dragon?
Personally, I think that today's issue may lead the guys in the Dragonrider design office sit down and at least recheck their math on that one.
ISTM, the battery (including any redundancy) only needs to last as long as the shortest-lived element of the life-support system.
cheers, Martin
It might also be a safety feature. I don't know the probabilities
but usually a static system (like the battery) will be more reliable than a non-static/dynamic system (fairings+mechanical opening of solar panels). So maybe the risk of the battery running out is much smaller than the risk of the solar panels not opening.
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But really, this sort of thing happens on every single launch of every single type of rocket - at least those which have onboard cameras - and seeing that footage is one of the main highlights for the viewing public.
Why can't somebody come up with a damn solution to this problem?
Because one is not needed.
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Actually, it's a simple roll of plastic which is spooled across the lens every few seconds.
Think of it like the film inside an old film camera, but in this case the plastic is a see-through lens cover. The dirty stuff simply winds onto the take-up spool and is not re-used.
It's a simple, low-mass, reliable system, though a little bulky I understand. It also copes OK with 5G+ braking and gets a pretty rough ride via the car's chassis. Whether it could be beefed up to cope with supersonic airflows I have no idea.
The cameras are behind the shock, generally inside the laminar flow region of the flow field. They don't have to survive supersonic airflow, but they do have to deal with acoustic and radiative/convective thermal loading, as well as the usual vibration environment that everything on the launch vehicle has to survive. So it's not what your typical Russian meteor-watching dashcam has to endure, but it's not like surviving the inside of a volcano either. :P
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One of the lessons learned from yesterday's incident is that there might be some benefit in emulating the Russian orbital insertion strategy for human flights: Soyuz is injected into a 245 x 190 km orbit that will decay within 24 hours unless the Soyuz thrusters fire to raise the orbit (which is done in Rev 2 or 3). Of course, the other benefit from the low initial orbit is that is allows the Soyuz to catch up with ISS faster.
The Soyuz approach saves the crew in the event that the thruster system suffers infant mortality and simply never works.
On the other hand, the SpaceX insertion altitude keeps Dragon on orbit for a couple of months if the thrusters fail completely.
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Interesting: Musks just said that the crewed Dragon that goes to the ISS wont have solar arrays, but a bigger battery instead. There will still be solar arrays for long duration missions. Wonder what else will be different...
I guess the battery will be in the reuseable part of the dragon?
Personally, I think that today's issue may lead the guys in the Dragonrider design office sit down and at least recheck their math on that one.
ISTM, the battery (including any redundancy) only needs to last as long as the shortest-lived element of the life-support system.
cheers, Martin
It's not Star Trek. Everybody doesn't collapse two seconds after life support fails.
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One of the lessons learned from yesterday's incident is that there might be some benefit in emulating the Russian orbital insertion strategy for human flights: Soyuz is injected into a 245 x 190 km orbit that will decay within 24 hours unless the Soyuz thrusters fire to raise the orbit (which is done in Rev 2 or 3). Of course, the other benefit from the low initial orbit is that is allows the Soyuz to catch up with ISS faster.
The Soyuz approach saves the crew in the event that the thruster system suffers infant mortality and simply never works.
On the other hand, the SpaceX insertion altitude keeps Dragon on orbit for a couple of months if the thrusters fail completely.
Elon said yesterday that the orbit Dragon was in would decay in 'a couple of days' of they didn't do a circularization burn.
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Here are the orbital elements for the 2nd stage:
2013-010B
1 39116U 13010B 13061.31448333 .00899770 11541-4 79078-3 0 109
2 39116 51.6760 278.9951 0083022 47.2216 313.5737 16.05050851 117
Empty rocket stages are basically balloons in the sense that they incur a lot of drag, so if Dragon were inserted into an orbit by this 2nd stage that would decay in a couple of days, this stage should be in the ocean by tomorrow. However, an orbital altitude that causes a rocket stage to decay in 2 days may support a capsule for a lot longer.
The reality is that Dragon is inserted into a 310 x 340 km orbit vs 190 x 240 km for Soyuz, so if you happen to be part of a Dragon crew that is riding in a capsule with no thrusters, you may have to hold your breath for a while, before coming home.
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This also came up yesterday:
Dragon's solar arrays are covered during ascent; the covers come off when the arrays are deployed. The implication is that zero power can be generated unless the deployment mechanisms work. However, the deployment mechanism have a single point failure mode where the command signal to deploy is inhibited.
Another approach would be to either drop the covers during launch (which has its own risks and rewards) or otherwise find a way to eject the covers at separation, so that even if the arrays do not deploy, SOME amount of power can be generated by the undeployed but uncovered array.
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The reality is that Dragon is inserted into a 310 x 340 km orbit vs 190 x 240 km for Soyuz
The reality is you got that number wrong. Both this Dragon and the last one were targeted for a 200 x 325 km orbit.
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Because one is not needed.
But we want our pretty pictures! (stamps foot).
ya, you're right, it's not critical. As long as the entire lens isn't obscured, I guess. But you watch, one of these times a glob of dirt (or alien slime ?) is going to obscure something important (like the turbo exhaust bell used for roll control failing to gimbal) and then what. :)
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ya, you're right, it's not critical. As long as the entire lens isn't obscured, I guess. But you watch, one of these times a glob of dirt (or alien slime ?) is going to obscure something important (like the turbo exhaust bell used for roll control failing to gimbal) and then what. :)
And they do what they did before cameras, look at telemetry.
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Another approach would be to either drop the covers during launch (which has its own risks and rewards) or otherwise find a way to eject the covers at separation, so that even if the arrays do not deploy, SOME amount of power can be generated by the undeployed but uncovered array.
Not necessarily. The arrays could be stowed with no cells facing outward.
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ya, you're right, it's not critical. As long as the entire lens isn't obscured, I guess. But you watch, one of these times a glob of dirt (or alien slime ?) is going to obscure something important (like the turbo exhaust bell used for roll control failing to gimbal) and then what. :)
And they do what they did before cameras, look at telemetry.
A picture is sometimes worth a thousand words.
Another approach would be to either drop the covers during launch (which has its own risks and rewards) or otherwise find a way to eject the covers at separation, so that even if the arrays do not deploy, SOME amount of power can be generated by the undeployed but uncovered array.
Not necessarily. The arrays could be stowed with no cells facing outward.
THAT seems an easy fix, make sure the last section faces outward! Either fold them the other way, or change the number of segments from even to odd (or odd to even) to make it come out that way.
But I doubt that 1/5 (or 1/6 or whatever the folded portion of the total is) of one panel facing at an oblique angle to the sun (as a random alignment would give you) is going to produce a lot of useful power. Might not be worth the added complexity of rigging the covers to come off as a separate action from the array deploy
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1. A picture is sometimes worth a thousand words.
2. THAT seems an easy fix, make sure the last section faces outward! Either fold them the other way, or change the number of segments from even to odd (or odd to even) to make it come out that way.
1. Better telemetry is worth more. Cameras have limited use and field of view, and high bandwith.
2. They are protected when pointed inward.
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How common are solar array deployment failures on commercial comm sats?
Indeed, none of the problems that Dragon had yesterday were specific to an almost-manned capsule, and could happen to any spacecraft/satellite with an RCS. This is more of SpaceX relearning things that others have been doing for years.
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Another approach would be to either drop the covers during launch (which has its own risks and rewards) or otherwise find a way to eject the covers at separation, so that even if the arrays do not deploy, SOME amount of power can be generated by the undeployed but uncovered array.
Not necessarily. The arrays could be stowed with no cells facing outward.
That's exactly how they are stowed - the white surface (no cells) is outside.
On the picture the part of folded panel is visible to the right of unattached cover:
http://mediaarchive.ksc.nasa.gov/imageviewer.cfm?mediaid=63999&mr=l&w=0&h=0&fn=2013-1110&sn=KSC-2013-1110
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How common are solar array deployment failures on commercial comm sats?
Indeed, none of the problems that Dragon had yesterday were specific to an almost-manned capsule, and could happen to any spacecraft/satellite with an RCS. This is more of SpaceX relearning things that others have been doing for years.
SpaceX has /also/ been doing this for years. ;)
Remember also that Dragon has a lot more failsafes than most satellites do. That contributed partly to the inhibiting of the thrusters (though it wasn't a bad idea).
Also, most spacecraft have much simpler RCS systems, i.e. they don't have eight propellant tanks. SpaceX is partially doing this for redundancy, but it all adds complication and increases the chances of getting non-LOM glitches like we just had. It's the same deal as with other redundant systems, it's completely unfair to compare non-LOM failure rate (like engine-outs, a single computer lock-up when you have three computers, etc) to failure rate that would mean LOM without redundancy (when you have just a single engine thus complete LOM if you have engine-out, just single-string computers, etc).
I'd rather have a non-LOM glitch rate of 10% in a system (with LOM rate of 0.1%) than a glitch-rate of 1% in a system where virtually all such glitches lead to LOM. What matters is LOM glitch rate, and in that sense, Dragon is doing perfect so far out of 4 launches. Falcon 9 as well (secondary early deorbit notwithstanding, considering it was entirely secondary).
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Another approach would be to either drop the covers during launch (which has its own risks and rewards) or otherwise find a way to eject the covers at separation, so that even if the arrays do not deploy, SOME amount of power can be generated by the undeployed but uncovered array.
Not necessarily. The arrays could be stowed with no cells facing outward.
THAT seems an easy fix, make sure the last section faces outward! Either fold them the other way, or change the number of segments from even to odd (or odd to even) to make it come out that way.
But I doubt that 1/5 (or 1/6 or whatever the folded portion of the total is) of one panel facing at an oblique angle to the sun (as a random alignment would give you) is going to produce a lot of useful power. Might not be worth the added complexity of rigging the covers to come off as a separate action from the array deploy
They probably don't have an issue during normal operation of the cells when unfolded, but there is a known issue with solar cell shadowing depending on how they are wired. Without going into details, on one of my university's recent nanosat cubesat missions we had solar cells fail because some of the cells were being shadowed while other cells were illuminated. Basically caused biasing of the cells in the wrong direction causing them to get fed current backwards through them. Result: LOM.
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How common are solar array deployment failures on commercial comm sats?
I can think of three in the last 10 years
Telstar 14 (Estrela do Sul 1)
Telstar 14R (Estrela do Sul 2)
Intelsat-19
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They probably don't have an issue during normal operation of the cells when unfolded, but there is a known issue with solar cell shadowing depending on how they are wired. Without going into details, on one of my university's recent nanosat cubesat missions we had solar cells fail because some of the cells were being shadowed while other cells were illuminated. Basically caused biasing of the cells in the wrong direction causing them to get fed current backwards through them. Result: LOM.
I think what you are touching is also an issue that even affects terrestrial solar cells. In grid tied terrestrial systems, multiple panels are placed in series and run through an inverter. The string will pretty much shut down when any of panels in the string are shadowed. (The terrestrial way around that is instead of using a single large inverter that takes multiple strings, is to put a micro inverter on each panel, more expensive, but it has advantages, google enphase M215).
For a partially exposed panel like being talked on the dragon, the exposed part would have to be it's own string. Otherwise you are right, it will not be producing any power.
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They probably don't have an issue during normal operation of the cells when unfolded, but there is a known issue with solar cell shadowing depending on how they are wired. Without going into details, on one of my university's recent nanosat cubesat missions we had solar cells fail because some of the cells were being shadowed while other cells were illuminated. Basically caused biasing of the cells in the wrong direction causing them to get fed current backwards through them. Result: LOM.
I think what you are touching is also an issue that even affects terrestrial solar cells. In grid tied terrestrial systems, multiple panels are placed in series and run through an inverter. The string will pretty much shut down when any of panels in the string are shadowed. (The terrestrial way around that is instead of using a single large inverter that takes multiple strings, is to put a micro inverter on each panel, more expensive, but it has advantages, google enphase M215).
For a partially exposed panel like being talked on the dragon, the exposed part would have to be it's own string. Otherwise you are right, it will not be producing any power.
The more expensive panels have in-cell electronics to avoid it. AFAIk, it can be as simple as a diode.
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How common are solar array deployment failures on commercial comm sats?
Indeed, none of the problems that Dragon had yesterday were specific to an almost-manned capsule, and could happen to any spacecraft/satellite with an RCS.
Remember also that Dragon has a lot more failsafes than most satellites do. That contributed partly to the inhibiting of the thrusters (though it wasn't a bad idea).
Also none of these "other Satellites" need an RCS to return home. Which necessitates the redundancies.
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They probably don't have an issue during normal operation of the cells when unfolded, but there is a known issue with solar cell shadowing depending on how they are wired. Without going into details, on one of my university's recent nanosat cubesat missions we had solar cells fail because some of the cells were being shadowed while other cells were illuminated. Basically caused biasing of the cells in the wrong direction causing them to get fed current backwards through them. Result: LOM.
I think what you are touching is also an issue that even affects terrestrial solar cells. In grid tied terrestrial systems, multiple panels are placed in series and run through an inverter. The string will pretty much shut down when any of panels in the string are shadowed. (The terrestrial way around that is instead of using a single large inverter that takes multiple strings, is to put a micro inverter on each panel, more expensive, but it has advantages, google enphase M215).
For a partially exposed panel like being talked on the dragon, the exposed part would have to be it's own string. Otherwise you are right, it will not be producing any power.
The more expensive panels have in-cell electronics to avoid it. AFAIk, it can be as simple as a diode.
What are the voltage drops of typical space solar panels when producing? A diode might be a significant part of that, causing inefficiency? Depending on the circuit
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They probably don't have an issue during normal operation of the cells when unfolded, but there is a known issue with solar cell shadowing depending on how they are wired. Without going into details, on one of my university's recent nanosat cubesat missions we had solar cells fail because some of the cells were being shadowed while other cells were illuminated. Basically caused biasing of the cells in the wrong direction causing them to get fed current backwards through them. Result: LOM.
I think what you are touching is also an issue that even affects terrestrial solar cells. In grid tied terrestrial systems, multiple panels are placed in series and run through an inverter. The string will pretty much shut down when any of panels in the string are shadowed. (The terrestrial way around that is instead of using a single large inverter that takes multiple strings, is to put a micro inverter on each panel, more expensive, but it has advantages, google enphase M215).
For a partially exposed panel like being talked on the dragon, the exposed part would have to be it's own string. Otherwise you are right, it will not be producing any power.
The more expensive panels have in-cell electronics to avoid it. AFAIk, it can be as simple as a diode.
What are the voltage drops of typical space solar panels when producing? A diode might be a significant part of that, causing inefficiency? Depending on the circuit
Depends on the cost. I know some cheap ones use diodes for boats, as you want a large surface that is constantly being partially covered either by a sail or a girl in a bikini. Efficiency is not the top priority in those cases.
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How common are solar array deployment failures on commercial comm sats?
Indeed, none of the problems that Dragon had yesterday were specific to an almost-manned capsule, and could happen to any spacecraft/satellite with an RCS.
Remember also that Dragon has a lot more failsafes than most satellites do. That contributed partly to the inhibiting of the thrusters (though it wasn't a bad idea).
Also none of these "other Satellites" need an RCS to return home. Which necessitates the redundancies.
(almost) none of them have to return home....
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Can anyone explain what "Second stage propellant utilization active" means? This call comes more than a minute after Mvac ignition which occurs at about 43:20 in the SpaceX launch webcast video.
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How common are solar array deployment failures on commercial comm sats?
Indeed, none of the problems that Dragon had yesterday were specific to an almost-manned capsule, and could happen to any spacecraft/satellite with an RCS.
Remember also that Dragon has a lot more failsafes than most satellites do. That contributed partly to the inhibiting of the thrusters (though it wasn't a bad idea).
Also none of these "other Satellites" need an RCS to return home. Which necessitates the redundancies.
(almost) none of them have to return home....
Soyuz is the only other, currently?
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Can anyone explain what "Second stage propellant utilization active" means? This call comes more than a minute after Mvac ignition which occurs at about 43:20 in the SpaceX launch webcast video.
It is going from open loop to close loop. Before this, the engine is running on fixed mixture ratio. After te point, it is measuring the propellant remaining and adjusting the mixture ratio to ensure simulateous depletion
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Can anyone explain what "Second stage propellant utilization active" means? This call comes more than a minute after Mvac ignition which occurs at about 43:20 in the SpaceX launch webcast video.
It is going from open loop to close loop. Before this, the engine is running on fixed mixture ratio. After te point, it is measuring the propellant remaining and adjusting the mixture ratio to ensure simulateous depletion
Excellent, thank you.
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(almost) none of them have to return home....
Soyuz is the only other, currently?
Shenzhou, X37B. HTV, ATV and Cygnus do the retro anyways.
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Sorry if it has been asked before, but this surprised me: In the CRS-2 Pre Launch briefing, Gwynne Shotwell said, that the downmass is part of SpaceX's 20mT CRS-contract. Is that true?
I sometimes get the impression that she really has no clue what she is talking about...
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Sorry if it has been asked before, but this surprised me: In the CRS-2 Pre Launch briefing, Gwynne Shotwell said, that the downmass is part of SpaceX's 20mT CRS-contract. Is that true?
Maybe you should go listen again.
I sometimes get the impression that she really has no clue what she is talking about...
Wow.
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Sorry if it has been asked before, but this surprised me: In the CRS-2 Pre Launch briefing, Gwynne Shotwell said, that the downmass is part of SpaceX's 20mT CRS-contract. Is that true?
Yes it is part of the contract. There was an option for a minimum (by value) of 3 MT down in addition to the 20 MT up (by value). NASA exercised the option.
I.A.3 INDEFINITE DELIVERY INDEFINITE QUANTITY (IDIQ), FIRM FIXED PRICE CONTRACT
The guaranteed minimum value of this contract is the negotiated value of 20,000 kg (20 MT) ofupmass to the International Space Station (ISS) based on the values established in Clause I.A.4. If the contract includes the acceptance of Sub-CLIN 0001AC, an additional guaranteed minimum value of this contract is increased by the negotiated value of 3,000 kg (3 MT) of Return Cargo Downmass, based on the values established in Clause I.A.4.
...
• All per kilogram pricing assumes cargo mass capacity fully utilized (3310 kg upmass and 3310 kg dowumass).
• Cargo load is variable and could be volume rather than mass limited. Because pricing is based on mass--per mission pricing is applicable for volume limited missions.
I sometimes get the impression that she really has no clue what she is talking about...
Uncalled for and out of line.
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Sorry if it has been asked before, but this surprised me: In the CRS-2 Pre Launch briefing, Gwynne Shotwell said, that the downmass is part of SpaceX's 20mT CRS-contract. Is that true?
I sometimes get the impression that she really has no clue what she is talking about...
If you notice Shotwell always tends to turn press conferences around to new contracts signed, and operational workflow. In most cases Presidents are focused on workflow and contracts. Mr Musk always brings the press conference around the the companies mission (CEO), and new products coming online (CTO).
Mr Musk is much less likely to be able to give you a good number on profit per customer, or name operationally responsible folks at the 3 facilities.
All the Senior staff of an organization are going to have a broad brush idea what's going on, but each are going to be different in the questions they can speak well to. Notice Mr Musk tends to trip up on financial questions and Shotwell trips on technical questions.
This is how it it with most large companies... It's completely normal.
http://www.spacex.com/company.php
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Sorry if it has been asked before, but this surprised me: In the CRS-2 Pre Launch briefing, Gwynne Shotwell said, that the downmass is part of SpaceX's 20mT CRS-contract. Is that true?
I sometimes get the impression that she really has no clue what she is talking about...
Heh, someone asked her about you, but she didn't have an opinion. Strange. :)
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Sorry if it has been asked before, but this surprised me: In the CRS-2 Pre Launch briefing, Gwynne Shotwell said, that the downmass is part of SpaceX's 20mT CRS-contract. Is that true?
Yes it is part of the contract. There was an option for a minimum (by value) of 3 MT down in addition to the 20 MT up (by value). NASA exercised the option.
I.A.3 INDEFINITE DELIVERY INDEFINITE QUANTITY (IDIQ), FIRM FIXED PRICE CONTRACT
The guaranteed minimum value of this contract is the negotiated value of 20,000 kg (20 MT) ofupmass to the International Space Station (ISS) based on the values established in Clause I.A.4. If the contract includes the acceptance of Sub-CLIN 0001AC, an additional guaranteed minimum value of this contract is increased by the negotiated value of 3,000 kg (3 MT) of Return Cargo Downmass, based on the values established in Clause I.A.4.
...
• All per kilogram pricing assumes cargo mass capacity fully utilized (3310 kg upmass and 3310 kg dowumass).
• Cargo load is variable and could be volume rather than mass limited. Because pricing is based on mass--per mission pricing is applicable for volume limited missions.
I sometimes get the impression that she really has no clue what she is talking about...
Uncalled for and out of line.
Here
http://www.youtube.com/watch?v=S6AwJrckc8s
at around 40:00ff she does the following math: " ...1050kg up, down is 1370kilos, for total around 2400 kilos, if you multiply it by 12, you would have more than the 20 metric tons, required under CRS, and that's as far as i am going with math in public."
In this statement she also references to a question that was asked earlier (around 16:45), where somebody asked if he did the math correctly, that 12 missions like crs-1 and 2 would only add up to 14.000kg of cargo. she answers (17:20) "The cargo requirement is 20 metric tons up and back."
To me, that suggests that she implies that the 20mT are up and downmass combined. Which is not true if i understand the quoted document correctly. Doesn't it say that there have to be 20mT up PLUS minimum 3mT down?
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Sorry if it has been asked before, but this surprised me: In the CRS-2 Pre Launch briefing, Gwynne Shotwell said, that the downmass is part of SpaceX's 20mT CRS-contract. Is that true?
I sometimes get the impression that she really has no clue what she is talking about...
Heh, someone asked her about you, but she didn't have an opinion. Strange. :)
:) I actually LOLed, i guess you are right ;)
I didn't want to step on anybody's toes, sorry for my comment about her. I just get so irritated when i see her saying this stuff that seems to be not 100% correct.
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@ohlongjohnson: It was stated, if I remember correct, in one of the last briefings, that NASA can change the requirements about up/down-mass ratio if needed. So, it's possible, that NASA like to have more downmass than the stated 3t.
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@ohlongjohnson: It was stated, if I remember correct, in one of the last briefings, that NASA can change the requirements about up/down-mass ratio if needed. So, it's possible, that NASA like to have more downmass than the stated 3t.
thanks!
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Interesting: Musks just said that the crewed Dragon that goes to the ISS wont have solar arrays, but a bigger battery instead. There will still be solar arrays for long duration missions. Wonder what else will be different...
I guess the battery will be in the reuseable part of the dragon?
This will change in the future. Think a couple of solar collectors would still be installed on the outside trunk like HTV. Can see the large solar panels (arrays) go away.
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In this statement she also references to a question that was asked earlier (around 16:45), where somebody asked if he did the math correctly, that 12 missions like crs-1 and 2 would only add up to 14.000kg of cargo. she answers (17:20) "The cargo requirement is 20 metric tons up and back."
To me, that suggests that she implies that the 20mT are up and downmass combined. Which is not true if i understand the quoted document correctly. Doesn't it say that there have to be 20mT up PLUS minimum 3mT down?
The simple answer is we don't really know. NASA's total published up-mass requirements are in the range of ~40t for CRS (+/- ~10t as best I can tell). If you assume that is evenly split between SpaceX and OSC, then a requirement for each to deliver ~20t would be a reasonable conclusion.
However, while the contract verbiage is nominally stated in mass, there are those qualifiers "the negotiated value" and "volume limited missions", which is a statement of minimum contract value not mass. We also don't know if there's a price differential for up- vs. down-mass.
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Interesting: Musks just said that the crewed Dragon that goes to the ISS wont have solar arrays, but a bigger battery instead. There will still be solar arrays for long duration missions. Wonder what else will be different...
I guess the battery will be in the reuseable part of the dragon?
This will change in the future. Think a couple of solar collectors would still be installed on the outside trunk like HTV. Can see the large solar panels (arrays) go away.
Those collectors would likely require protection during ascent--protection which would have to be subsequently jettisoned? If they can meet the requirements without, what benefit would that provide?
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Interesting: Musks just said that the crewed Dragon that goes to the ISS wont have solar arrays, but a bigger battery instead. There will still be solar arrays for long duration missions. Wonder what else will be different...
I guess the battery will be in the reuseable part of the dragon?
This will change in the future. Think a couple of solar collectors would still be installed on the outside trunk like HTV. Can see the large solar panels (arrays) go away.
So I guess Elon doesn't know what he is talking about? :D Arguing interpretation is one thing, but now you are claiming that he is wrong, and it *will* be different? I know you think they are a mickey mouse group, but c'mon...
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Sorry if it has been asked before, but this surprised me: In the CRS-2 Pre Launch briefing, Gwynne Shotwell said, that the downmass is part of SpaceX's 20mT CRS-contract. Is that true?
I sometimes get the impression that she really has no clue what she is talking about...
Heh, someone asked her about you, but she didn't have an opinion. Strange. :)
:) I actually LOLed, i guess you are right ;)
I didn't want to step on anybody's toes, sorry for my comment about her. I just get so irritated when i see her saying this stuff that seems to be not 100% correct.
:) I aim to please ....
and btw, yes, when you get used to seeing a CEO like Elon Musk, everyone else sort of pales in comparison. I am sure she's not the one coming up with the strategic technical plan, but she IS the one that leaves the meeting room with positive results.
Do you remember the predictions on this forum about how long it will take SpaceX to even get in the DOD door? It's not just their technical magic show that's paving their way.
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From the party thread:
On a side note, I'm disappointed with the rocketcams they flew the last two missions. They said they changed something, but it didn't improve quality and in fact it seems to have dropped the frame rate from the full 30 fps.
Found this about the video system in the meantime:
This footage came thru the VID/103 module in the CWC-AE Acra KAM-500 onboard #SpaceX Falcon 9 on Friday.
source: https://twitter.com/cwcae/status/308547914026848256
VID/103 is labeled (http://www.etmc.com.au/agencies1-1a.html) as an MPEG-4 encoder so that confirms my suspicion the rocketcam feed is all digital now, right from the vehicle. Previous F9 flights seemed to use primarily analog NTSC video, but possibly "experimental" digital as secondary as there were certain feed drops/switches in the past that made me suspect there was a format change involved.
Now, if they would only stop feeding interlaced frames to that MPEG-4 encoder to get rid of those ugly checkerboard pattern artifacts... ::)
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This will change in the future. Think a couple of solar collectors would still be installed on the outside trunk like HTV. Can see the large solar panels (arrays) go away.
Those collectors would likely require protection during ascent--protection which would have to be subsequently jettisoned? If they can meet the requirements without, what benefit would that provide?
...or, if they do go with that, just coat any such panels with Gorilla Glass?
cheers, Martin
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Do you remember the predictions on this forum about how long it will take SpaceX to even get in the DOD door? It's not just their technical magic show that's paving their way.
It isn't her either. They are their either.
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Do you remember the predictions on this forum about how long it will take SpaceX to even get in the DOD door? It's not just their technical magic show that's paving their way.
It isn't her either. They are their either.
Please explain, Jim. Even by your standards, this is cryptic. I'm not even sure the last sentence has syntactical meaning.
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"They aren't there, either."
;)
Whenever Jim says something that doesn't make sense , just assume he meant to put in a "No" or something in there. ;)
(http://cdn.memegenerator.net/instances/400x/31220121.jpg)
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Do you remember the predictions on this forum about how long it will take SpaceX to even get in the DOD door? It's not just their technical magic show that's paving their way.
It isn't her either. They are their either.
Jim logged into the forums while drunk?
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Does the trunk significantly protect Dragon's heat shield from (micro)meteors, space junk or solar heating?
With talk of skipping solar panels for Dragon 2.0, it would seem deadweight after Falcon separation. If there's no external cargo, maybe they could jettison it at separation time.
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Does the trunk significantly protect Dragon's heat shield from (micro)meteors, space junk or solar heating?
With talk of skipping solar panels for Dragon 2.0, it would seem deadweight after Falcon separation. If there's no external cargo, maybe they could jettison it at separation time.
The radiators are on the trunk.
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Does the trunk significantly protect Dragon's heat shield from (micro)meteors, space junk or solar heating?
With talk of skipping solar panels for Dragon 2.0, it would seem deadweight after Falcon separation. If there's no external cargo, maybe they could jettison it at separation time.
Simple material in the way of a micrometeorite helps a lot actually. It acts to both use up energy of the incoming projectile and also break it up. Look up the Whipple Shield. Not quite as good as full out shield, but one layer helps. http://en.wikipedia.org/wiki/Whipple_shield
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In this statement she also references to a question that was asked earlier (around 16:45), where somebody asked if he did the math correctly, that 12 missions like crs-1 and 2 would only add up to 14.000kg of cargo. she answers (17:20) "The cargo requirement is 20 metric tons up and back."
To me, that suggests that she implies that the 20mT are up and downmass combined. Which is not true if i understand the quoted document correctly. Doesn't it say that there have to be 20mT up PLUS minimum 3mT down?
The simple answer is we don't really know. NASA's total published up-mass requirements are in the range of ~40t for CRS (+/- ~10t as best I can tell). If you assume that is evenly split between SpaceX and OSC, then a requirement for each to deliver ~20t would be a reasonable conclusion.
However, while the contract verbiage is nominally stated in mass, there are those qualifiers "the negotiated value" and "volume limited missions", which is a statement of minimum contract value not mass. We also don't know if there's a price differential for up- vs. down-mass.
Ideally, the question should have been asked to Gerst who was also on the conference call. There is some logic in NASA paying the same amount for downmass than it is paying for upmass. It is obvious that SpaceX will exceed the 3mT option for downmass. There may have been an amendment to the CRS contract that is not posted on the commercial crew and cargo reference library. For the time being, we have to assume that Shotwell's answer is correct.
http://www.nasa.gov/exploration/commercial/document_library.html
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At least back in 2008 (http://www.nasa.gov/home/hqnews/2008/dec/HQ_C08-069_ISS_Resupply.html) the upmass requirement was pretty clear text.
The contracts each call for the delivery of a minimum of 20 metric tons of upmass cargo to the space station.
If since altered shouldn't Joe the taxpayer have the right to know what kind of contract NASA currently has?
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I am not going to comment about contractual issues. All I can say is that downmass is extremely valuable for research, whereas for upmass there are currently plenty of alternatives.
I recently went to a lecture about radiation measurements on the columbus module. The researcher was really happy that he would get his radiation measurement devices back due to dragon downmass capability.
The passive radiation measurement devices are really tiny, so they can squeeze them into a soyuz with the returning crew. But the active experiments and the dummies are quite large, so without the dragon they would have to be discarded. If I remember correctly they got some equipment down with the last STS mission, which has now been launched to the station again.
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Never downplay downmass !
(sorry, coudn't resist... ::))
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It does appear that Dragon is being used for more downmass than CRS originally seemed to stipulate.
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It does appear that Dragon is being used for more downmass than CRS originally seemed to stipulate.
I have my suspicions that the terms of the CRS contracts was based on a lot of politically-motivated and highly-dubious assumptions.
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At least back in 2008 (http://www.nasa.gov/home/hqnews/2008/dec/HQ_C08-069_ISS_Resupply.html) the upmass requirement was pretty clear text.
The contracts each call for the delivery of a minimum of 20 metric tons of upmass cargo to the space station.
Actually, re-reading the CRS SpaceX contract, the 3mT is only a minimum value (if the return cargo downmass option is exercised). The agreement seems to allow for more than that (the total maximum value of the contract can be as high as $3.1B). It is not clear if the 20mT is the minimum amount of upmass cargo since it only says that it is the minimum value of the contract. It could be that you are allowed to substitute downmass return cargo for upmass cargo as Shotwell implied. If this is the case, this would mean that SpaceX must bring 23mT of cargo up or down. Given that Shotwell signed the 2009 amendments to the CRS agreement, I am assuming that she knows what she is talking about. A lot of the CRS contract is redacted, so I wouldn't assume that she is wrong.
I.A.3 INDEFINITE DELIVERY INDEFINITE QUANTITY (IDIQ), FIRM FIXED PRICE CONTRACT
In accordance with Clause VI.A.5, Single or Multiple Awards (FAR 52.216-27) (Oct 1995), NASA may elect to award multiple contracts. The guaranteed minimum value of this contract is the negotiated value of 20,000 kg (20 MT) of upmass to the International Space Station (ISS) based on the values established in Clause I.A.4. If the contract includes the acceptance of Sub-CLIN 0001AC, an additional guaranteed minimum value of this contract is increased by the negotiated value of 3,000 kg (3 MT) of Return Cargo Downmass, based on the values established in Clause I.A.4. The total maximum value of each contract awarded is $3.1 billion.
See pages 7 and 8 of the PDF:
http://www.nasa.gov/centers/johnson/pdf/418857main_sec_nnj09ga04b.pdf
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I would expect, myself, that the price for downmass would be higher than that for upmass. If they are equal, NASA is getting a bargain.
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I would expect, myself, that the price for downmass would be higher than that for upmass. If they are equal, NASA is getting a bargain.
Given COTS/CRS where a gamble, and if things had turned out differently NASA could have spent nearly 500 Million on SpaceX and not got an ounce of cargo to/from the ISS, I think a sweetheart deal on downmass could be very well possible.
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SpaceX has a unique ability in the fact that they can bring back large amts. of downmass from the ISS and they know it. SpaceX reminds us about it all the time, when they put out press statements.
Elon is very savvy, I would be surprized if they would only get a one to one trade off with up mass.
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SpaceX has a unique ability in the fact that they can bring back large amts. of downmass from the ISS and they know it. SpaceX reminds us about it all the time, when they put out press statements.
Elon is very savvy, I would be surprized if they would only get a one to one trade off with up mass.
Correct, but savvy does not necessarily mean near-term greedy. NASA is not SpaceX's ultimate source of money. However, they ARE the bootstrap customer, and more importantly - the gatekeepers of cred.
If he is giving them a sweet deal on something that they cannot get anywhere else, it generates a ton of good will. Which you later see when they are open-minded to allow a spacecraft to dock even though it had a serious propulsion glitch, or the Lidar was misbehaving, or even flexibility with backloading the upmass... Not to mention the tons of accolades SpaceX gets from the astronauts and NASA management in general - all this stuff is worth a lot more than the extra $ he could have squeezed out of them.
"Good will begets good will"
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It does appear that Dragon is being used for more downmass than CRS originally seemed to stipulate.
I have my suspicions that the terms of the CRS contracts was based on a lot of politically-motivated and highly-dubious assumptions.
What are you trying to say? Come out and say it directly.
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It does appear that Dragon is being used for more downmass than CRS originally seemed to stipulate.
I have my suspicions that the terms of the CRS contracts was based on a lot of politically-motivated and highly-dubious assumptions.
What are you trying to say? Come out and say it directly.
Well this fits into that other "goodwill" discussion. Maybe, just maybe, SpaceX is giving NASA a sweet deal on downmass, and NASA is being flexible on the distribution of upmass, and everyone is happy without being sinister. It might just be a good working relationship with a vendor that actually delivers.
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Actually, re-reading the CRS SpaceX contract, the 3mT is only a minimum value (if the return cargo downmass option is exercised). The agreement seems to allow for more than that (the total maximum value of the contract can be as high as $3.1B). It is not clear if the 20mT is the minimum amount of upmass cargo since it only says that it is the minimum value of the contract. It could be that you are allowed to substitute downmass return cargo for upmass cargo as Shotwell implied. If this is the case, this would mean that SpaceX must bring 23mT of cargo up or down. Given that Shotwell signed the 2009 amendments to the CRS agreement, I am assuming that she knows what she is talking about. A lot of the CRS contract is redacted, so I wouldn't assume that she is wrong.
Yes (http://forum.nasaspaceflight.com/index.php?topic=30385.msg1021803#msg1021803), also note the qualifiers following that paragraph (http://forum.nasaspaceflight.com/index.php?topic=30385.msg1021787#msg1021787) for "pricing assumes cargo mass capacity fully utilized" and "per mission pricing is applicable for volume limited missions".
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Actually, re-reading the CRS SpaceX contract, the 3mT is only a minimum value (if the return cargo downmass option is exercised). The agreement seems to allow for more than that (the total maximum value of the contract can be as high as $3.1B). It is not clear if the 20mT is the minimum amount of upmass cargo since it only says that it is the minimum value of the contract. It could be that you are allowed to substitute downmass return cargo for upmass cargo as Shotwell implied. If this is the case, this would mean that SpaceX must bring 23mT of cargo up or down. Given that Shotwell signed the 2009 amendments to the CRS agreement, I am assuming that she knows what she is talking about. A lot of the CRS contract is redacted, so I wouldn't assume that she is wrong.
Yes (http://forum.nasaspaceflight.com/index.php?topic=30385.msg1021803#msg1021803), also note the qualifiers following that paragraph (http://forum.nasaspaceflight.com/index.php?topic=30385.msg1021787#msg1021787) for "pricing assumes cargo mass capacity fully utilized" and "per mission pricing is applicable for volume limited missions".
That is a very good point. This also suggests that the 20mT is probably not a hard requirement for CRS but only a minimum value for the contract.
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I recall Elon being a bit miffed that SpaceX was paid less for their cargo trips than Orbital therefore doubtful that there was any intent to give NASA a 'sweet' deal.
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I'm attending a Q&A session with SpaceX tomorrow. The blurb says "they will take any and all questions." I doubt they'll take all of mine!
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It might just be a good working relationship with a vendor that actually delivers.
What vendors don't deliver for NASA?
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What vendors don't deliver for NASA?
Rephrase: "What vendors don't deliver for NASA at a reasonable and predictable price point?" While "reasonable" and "predictable" are subject to interpretation, SOMD's price shock over the last couple years suggest those vendors can not deliver at a reasonable and predictable price point.
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What vendors don't deliver for NASA?
Rephrase: "What vendors don't deliver for NASA at a reasonable and predictable price point?" While "reasonable" and "predictable" are subject to interpretation, SOMD's price shock over the last couple years suggest those vendors can not deliver at a reasonable and predictable price point.
Which vendors are those? Non HSF SOMD contractors meet contract costs and don't exceed them. And what SOMD's price shock?
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I would expect, myself, that the price for downmass would be higher than that for upmass. If they are equal, NASA is getting a bargain.
Just about any price for downmass must be mostly profit for SpaceX. How much does it actually cost them extra over what their expenses are with an empty Dragon being returned?
Having said that, they are currently in a near-monopoly position with regards to downmass capability, and could charge ridiculously high prices if they wanted to. It would be a terrible customer relations move that would be almost certain to backfire horribly down the road, but they could.
My own guess is that they will charge the contracted prices for the first 3000 kg of downmass, and then charge a nominal price for everything beyond that (potentially several tens of thousands of kg in the remaining flights under contract).
Dragon will bring back ~2940 kg on the first three flights alone (665 kg on C2+, 905 kg on CRS-1 and ~1370 kg on CRS-2), so SpaceX will have already almost met the contractual requirements.
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Having said that, they are currently in a near-monopoly position with regards to downmass capability, and could charge ridiculously high prices if they wanted to. It would be a terrible customer relations move that would be almost certain to backfire horribly down the road, but they could.
My own guess is that they will charge the contracted prices for the first 3000 kg of downmass, and then charge a nominal price for everything beyond that (potentially several tens of thousands of kg in the remaining flights under contract).
No, they are under a fixed price IDIQ contract. The cost for downmass has already been set. The 3000kg is just the minimum order for the downmass option in the contract, meaning if exercises the option, NASA is going to order at least that amount. The applies to the 20mt going up. That is the minimum NASA will order on the contract. NASA can buy as much upmass from Spacex and OSC and downmass from Spacex as long as it doesn't exceed 3.1B
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No, they are under a fixed price IDIQ contract. The cost for downmass has already been set. The 3000kg is just the minimum order for the downmass option in the contract, meaning if exercises the option, NASA is going to order at least that amount.
I stand corrected. Of course, under a fixed-price contract, NASA would be stupid not to take full advantage of the available downmass capability.
Oh wait, you edited your comment. So Nasa has to pay a fixed price per kg for downmass? Is there any information on what SpaceX will charge NASA for additional downmass?
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Dragon will bring back ~2940 kg on the first three flights alone (665 kg on C2+, 905 kg on CRS-1 and ~1370 kg on CRS-2), so SpaceX will have already almost met the contractual requirements.
No, that is almost meeting NASA's minimum order for downmass.
The 3000kg minimum is a guarantee from NASA that if a contract provides a down mass capability, NASA will order at least that amount.
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What vendors don't deliver for NASA?
Rephrase: "What vendors don't deliver for NASA at a reasonable and predictable price point?" While "reasonable" and "predictable" are subject to interpretation, SOMD's price shock over the last couple years suggest those vendors can not deliver at a reasonable and predictable price point.
Which vendors are those? Non HSF SOMD contractors meet contract costs and don't exceed them. And what SOMD's price shock?
That would be ULA (at least at this time).
True, non-HSF SOMD contractors meet contract costs--but given that ULA is the only viable supplier at this time, that counts for what? As to SOMD's price shock, the rather significant increase in cost under NLS II, and the concerns expressed by SOMD as to the impact speaks for itself.
Or do you suggest that the GAO's and NASA IG's concerns are irrelevant? They certainly seem to believe that those "Non HSF SOMD contractors meet contract costs and don't exceed them" are at best something NASA has to live with, rather that an optimal solution.
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NASA would be stupid not to take full advantage of the available downmass capability.
No, not at the expense of upmass. They get paid for from the the same pot of money.
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That would be ULA (at least at this time).
True, non-HSF SOMD contractors meet contract costs--but given that ULA is the only viable supplier at this time, that counts for what? As to SOMD's price shock, the rather significant increase in cost under NLS II, and the concerns expressed by SOMD as to the impact speaks for itself.
Or do you suggest that the GAO's and NASA IG's concerns are irrelevant? They certainly seem to believe that those "Non HSF SOMD contractors meet contract costs and don't exceed them" are at best something NASA has to live with, rather that an optimal solution.
Wrong. SOMD was not shocked. It was SMD.
And yes, it is something NASA has to live with and it isn't that bad.
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Wrong. SOMD was not shocked. It was SMD.
Fine, the presentations I've seen don't appear to make a distinction, but I'll take your word for it. So SMD was shocked, not SOMD; the fact remains that they were surprised. Ok, maybe "surprised" isn't the right word, but maybe more "holy cra*p, we didn't think this would happen... but now it has".
And yes, it is something NASA has to live with and it isn't that bad.
Yeah, NASA obviously has to live with it, but last I checked, "isn't that bad" could be several hundred $M/yr or on the order of $100M/launch for NASA. Or has the DoD backed off on their demand?
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I would expect, myself, that the price for downmass would be higher than that for upmass. If they are equal, NASA is getting a bargain.
Just about any price for downmass must be mostly profit for SpaceX. How much does it actually cost them extra over what their expenses are with an empty Dragon being returned?
Having said that, they are currently in a near-monopoly position with regards to downmass capability, and could charge ridiculously high prices if they wanted to. It would be a terrible customer relations move that would be almost certain to backfire horribly down the road, but they could.
My own guess is that they will charge the contracted prices for the first 3000 kg of downmass, and then charge a nominal price for everything beyond that (potentially several tens of thousands of kg in the remaining flights under contract).
Dragon will bring back ~2940 kg on the first three flights alone (665 kg on C2+, 905 kg on CRS-1 and ~1370 kg on CRS-2), so SpaceX will have already almost met the contractual requirements.
It doesn't matter what the cost is - the value of providing downmass capability is higher than that for upmass, because of the scarcity of options. Hence the downmass price should be higher - if SpaceX are negotiating sensibly.
In fact there's nothing in the available part of the contracts to suggest that the prices are equal, now I read them properly.
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NASA would be stupid not to take full advantage of the available downmass capability.
No, not at the expense of upmass. They get paid for from the the same pot of money.
Jim are they paid more for greater up mass?
Are they paid more for greater down mass?
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I would expect, myself, that the price for downmass would be higher than that for upmass. If they are equal, NASA is getting a bargain.
Just about any price for downmass must be mostly profit for SpaceX. How much does it actually cost them extra over what their expenses are with an empty Dragon being returned?
Offhand my guess at the incremental costs for downmass are
- slightly more propellant used in maneuvering on the way home (leaving the station, reentry, etc) ... probably pretty marginal
- labor to safe the payloads (if any such safing is needed), unpack, repack for transport, etc
- earthside transport costs not otherwise borne by NASA
What did I miss?
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I would expect, myself, that the price for downmass would be higher than that for upmass. If they are equal, NASA is getting a bargain.
Just about any price for downmass must be mostly profit for SpaceX. How much does it actually cost them extra over what their expenses are with an empty Dragon being returned?
Offhand my guess at the incremental costs for downmass are
- slightly more propellant used in maneuvering on the way home (leaving the station, reentry, etc) ... probably pretty marginal
- labor to safe the payloads (if any such safing is needed), unpack, repack for transport, etc
- earthside transport costs not otherwise borne by NASA
What did I miss?
Higher heat shield wear if/when cargo Dragons start to get reused. Less time between heat shield replacements.
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Hence the downmass price should be higher - if SpaceX are negotiating sensibly.
There is no negotiating. The price was set 5 years ago when the CRS contract was awarded. An IDIQ contract has fixed prices for various services. The gov't just orders up what services it needs. Upmass, downmass, late installation, power, early removal, etc all have a fixed price per unit of measurement.
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I would expect, myself, that the price for downmass would be higher than that for upmass. If they are equal, NASA is getting a bargain.
Just about any price for downmass must be mostly profit for SpaceX. How much does it actually cost them extra over what their expenses are with an empty Dragon being returned?
Offhand my guess at the incremental costs for downmass are
- slightly more propellant used in maneuvering on the way home (leaving the station, reentry, etc) ... probably pretty marginal
- labor to safe the payloads (if any such safing is needed), unpack, repack for transport, etc
- earthside transport costs not otherwise borne by NASA
What did I miss?
Higher heat shield wear if/when cargo Dragons start to get reused. Less time between heat shield replacements.
This might be case of not seeing the forest from the trees. Of course downmass has cost, because making a vehicle returnable has cost. That's why nobody else (ATV, HTV, Cygnus, Progress) is doing it. It is convenient for NASA that SpaceX's long term goals include crew transport, but that doesn't mean that Dragon's downmass capability comes "free".
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Hence the downmass price should be higher - if SpaceX are negotiating sensibly.
There is no negotiating. The price was set 5 years ago when the CRS contract was awarded. An IDIQ contract has fixed prices for various services. The gov't just orders up what services it needs. Upmass, downmass, late installation, power, early removal, etc all have a fixed price per unit of measurement.
I would expect a call-off price for services, yes. I guess I had forgotten that the CRS award was that far back, and as a competitive tender I don't recall if there were any other offers of downmass, so SpaceX would have had to guess a little on their offer. But it was apparent even then that the other international partners were providing plenty of upmass, so I would still have thought the downmass would have a premium.
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NASA would be stupid not to take full advantage of the available downmass capability.
No, not at the expense of upmass. They get paid for from the the same pot of money.
So you are saying that SpaceX has to bring 20mT of upmass cargo on 12 flights unless some of the flights are volume limited. That means that what Shotwell said at the press conference about upmass and downmass being interchangeable was incorrect. I suppose this also means that Space is likely to earn more than $1.6B dollars on its contract given that it will likely exceed the minimum downmass return cargo of 3mT.
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I would expect, myself, that the price for downmass would be higher than that for upmass. If they are equal, NASA is getting a bargain.
Just about any price for downmass must be mostly profit for SpaceX. How much does it actually cost them extra over what their expenses are with an empty Dragon being returned?
Offhand my guess at the incremental costs for downmass are
- slightly more propellant used in maneuvering on the way home (leaving the station, reentry, etc) ... probably pretty marginal
- labor to safe the payloads (if any such safing is needed), unpack, repack for transport, etc
- earthside transport costs not otherwise borne by NASA
What did I miss?
Higher heat shield wear if/when cargo Dragons start to get reused. Less time between heat shield replacements.
Right, I forgot that there may be incrementally more wear per return to the PICA-X due to the higher mass of the vehicle. A lot of these are hard to quantify and some seem like fairly low cost effects, although not zero.
What else would have more wear and tear? How about the lifetime of the SuperDracos? If they have to burn longer per return, they will need to be R&Red more frequently... (I remembered the fuel, LOL, but forgot the firing time on the thrusters is a finite resource as welll)
This might be case of not seeing the forest from the trees. Of course downmass has cost, because making a vehicle returnable has cost. That's why nobody else (ATV, HTV, Cygnus, Progress) is doing it. It is convenient for NASA that SpaceX's long term goals include crew transport, but that doesn't mean that Dragon's downmass capability comes "free".
I'm not saying it's free! But I think it's not as expensive per kg as upmass, all in all.
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NASA would be stupid not to take full advantage of the available downmass capability.
No, not at the expense of upmass. They get paid for from the the same pot of money.
So you are saying that SpaceX has to bring 20mT of upmass cargo on 12 flights unless some of the flights are volume limited.
No, I meant that NASA can't use up the contract limit just on downmass. It has to work out how it is going allocate downmass and upmass against the contract limit and minimums.
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NASA would be stupid not to take full advantage of the available downmass capability.
No, not at the expense of upmass. They get paid for from the the same pot of money.
So you are saying that SpaceX has to bring 20mT of upmass cargo on 12 flights unless some of the flights are volume limited.
No, I meant that NASA can't use up the contract limit just on downmass. It has to work out how it is going allocate downmass and upmass against the contract limit and minimums.
So NASA could decide to bring less than 20mT of upmass cargo and more than 3mT of downmass and still respect the contract. Correct?
Do you think that SpaceX could end up getting the maximum amount of $3.1B because it is delivering both upmass cargo and downmass return cargo?
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Do you think that SpaceX could end up getting the maximum amount of $3.1B because it is delivering both upmass and downmass return cargo?
I thought the $3.1B limit would be a case of NASA buying more resupply flights, not a case of buying more cargo per flight. I thought the current 12 flight prices were set in stone.
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Do you think that SpaceX could end up getting the maximum amount of $3.1B because it is delivering both upmass cargo and downmass return cargo?
No, there is still is OSC allocation of about $1.6B
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Do you think that SpaceX could end up getting the maximum amount of $3.1B because it is delivering both upmass cargo and downmass return cargo?
No, there is still is OSC allocation of about $1.6B
Space X gets $1.6B and Orbital gets $1.9B for a total of $3.5B. But the $3.1B is the maximum amount for each contract individually (not for both companies). It's not clear from the contract if this includes amounts for additionnal flights or if it's for additional return cargo downmass, etc. (it might be both). I thought that you might know how the CRS contracts work because the contracts are not clear since they are heavily redacted.
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Shotwell was proud to say that they would obliterate the minimum cargo expectations. This is part of the commercial paradigm shift. In both the short and long term, SpaceX wants to over-deliver and not haggle about incrementals. It's what those of us who run our own competitive private businesses do.This is how you successfully compete.
SpaceX isn't looking to say, "Hey there's your 20, have a nice day." They want and will be a flexible, reliable, extremely cost efficient NASA service provider that goes way above and beyond. And thank heavens for them.
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Space X gets $1.6B and Orbital gets $1.9B for a total of $3.5B. But the $3.1B is the maximum amount for each contract individually (not for both companies). It's not clear from the contract if this includes amounts for additionnal flights or if it's for additional return cargo downmass, etc. (it might be both). I thought that you might know how the CRS contracts work because the contracts are not clear since they are heavily redacted.
Sorry, I was getting my billions mixed up. I believe the number of flights is the 20 already contracted and is fixed. The difference between current and max contract amounts is for items such as power for experiments, late installation, early removal and down mass.
CRS was patterned after NLS I.
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Space X gets $1.6B and Orbital gets $1.9B for a total of $3.5B. But the $3.1B is the maximum amount for each contract individually (not for both companies). It's not clear from the contract if this includes amounts for additionnal flights or if it's for additional return cargo downmass, etc. (it might be both). I thought that you might know how the CRS contracts work because the contracts are not clear since they are heavily redacted.
Sorry, I was getting my billions mixed up. I believe the number of flights is the 20 already contracted and is fixed. The difference between current and max contract amounts is for items such as power for experiments, late installation, early removal and down mass.
CRS was patterned after NLS I.
Thanks Jim for making how the CRS contracts work clearer to us.
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I would expect a call-off price for services, yes. I guess I had forgotten that the CRS award was that far back, and as a competitive tender I don't recall if there were any other offers of downmass, so SpaceX would have had to guess a little on their offer. But it was apparent even then that the other international partners were providing plenty of upmass, so I would still have thought the downmass would have a premium.
Orbital (albeit, their offer was taken later), did offered to have a returnable version of Cygnus. They were told to concentrate on the disposable version. If you look at it, it might or might not have been a bad decision. They are getting one supplier with downmass capability (Dragon) and another with atmospheric disposal and plenty of pressurized module (Cygnus). Of course HTV does supply lots of pressurized, unpressurized and atmospheric disposal. But the retirement of the ATV does generates a logistical problem (on top of the Shuttle's).
On the other hand, they might have thought that they would have had an American crewed vehicle by now that could supply alternative downmass (probably Ares I + Orion, or commercial crew). I don't know also, what life horizon for the ISS they were expecting when they told that to the ISS. May be they thought they were going to deorbit it by 2017, so it was not such a hit. As of now, if we take a reasonable 2025 as a deorbit date, they might have a downmass limitation until they have commercial crew. And if Dragon is chosen, they will have a single system risk for downmass. Even if Cargo Dragon and Dragonrider are kept as separate systems, thy will share lots of systems and the same LV.
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I would expect a call-off price for services, yes. I guess I had forgotten that the CRS award was that far back, and as a competitive tender I don't recall if there were any other offers of downmass, so SpaceX would have had to guess a little on their offer. But it was apparent even then that the other international partners were providing plenty of upmass, so I would still have thought the downmass would have a premium.
Orbital (albeit, their offer was taken later), did offered to have a returnable version of Cygnus. They were told to concentrate on the disposable version. If you look at it, it might or might not have been a bad decision. They are getting one supplier with downmass capability (Dragon) and another with atmospheric disposal and plenty of pressurized module (Cygnus). Of course HTV does supply lots of pressurized, unpressurized and atmospheric disposal. But the retirement of the ATV does generates a logistical problem (on top of the Shuttle's).
On the other hand, they might have thought that they would have had an American crewed vehicle by now that could supply alternative downmass (probably Ares I + Orion, or commercial crew). I don't know also, what life horizon for the ISS they were expecting when they told that to the ISS. May be they thought they were going to deorbit it by 2017, so it was not such a hit. As of now, if we take a reasonable 2025 as a deorbit date, they might have a downmass limitation until they have commercial crew. And if Dragon is chosen, they will have a single system risk for downmass. Even if Cargo Dragon and Dragonrider are kept as separate systems, thy will share lots of systems and the same LV.
That's why I would love to see two commercial crew providers with no commonality, that can provide both crew and cargo delivery and return.
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Space X gets $1.6B and Orbital gets $1.9B for a total of $3.5B. But the $3.1B is the maximum amount for each contract individually (not for both companies). It's not clear from the contract if this includes amounts for additionnal flights or if it's for additional return cargo downmass, etc. (it might be both). I thought that you might know how the CRS contracts work because the contracts are not clear since they are heavily redacted.
Sorry, I was getting my billions mixed up. I believe the number of flights is the 20 already contracted and is fixed. The difference between current and max contract amounts is for items such as power for experiments, late installation, early removal and down mass.
CRS was patterned after NLS I.
Thanks that's very helpful.
The only thing that I am still not sure about is if Spacex can bring 12mT upmass and 12 mT downmass during its 12 flights and say that it has fulfilled its 20mT upmass and 3mT downmass obligations because it has exceeded the required combined total of 23mT (20mT +3mT). Shotwell implied that this was the case but I still don't know for sure if that is true.
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The contract talks about fulfilling the contract value of the 20t of upmass and the 3t of downmass. These may not have the same value per ton, but the implication as I read it is that the combined value of services is what is required. So imagine for simplicity that 1t of upmass is $2m and 1t of downmass is $3m, then the transportation contract value would be $49m, and any combination of upmass and downmass that reaches that value fulfills the contract.
That doesn't mean that no more cargo is allowed after that. It just means the minimum value has been fulfilled.
(There are complications to that also, when the cargo is volume-limited, meaning that extra value will accrue to that flight to represent the "lost" mass transport potential.)
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I recall Elon being a bit miffed that SpaceX was paid less for their cargo trips than Orbital therefore doubtful that there was any intent to give NASA a 'sweet' deal.
I suspect that Elon being 'miffed' was more about giving that impression to the media so that they would be more likely to cover the story; which, after all, does underline that SpaceX is cheaper!
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The only thing that I am still not sure about is if Spacex can bring 12mT upmass and 12 mT downmass during its 12 flights and say that it has fulfilled its 20mT upmass and 3mT downmass obligations because it has exceeded the required combined total of 23mT (20mT +3mT). Shotwell implied that this was the case but I still don't know for sure if that is true.
NASA may order more or less. This is IDIQ, and nothing was "purchased" by execution of the CRS contract--that is done through individually competed and awarded task orders* (as Jim stated same model as NLS, give-or-take a bit); e.g., see (emphasis added):
INDEFINITE QUANTITY (FAR 52.216-22) (OCT 1995)
(h) This is an indefinite-quantity contract for the supplies or services specified and effective for the period stated in Clause I.A.2. The quantities of supplies and services specified in the Schedule are estimates only and are not purchased by this contract.
(i) Delivery or performance shall be made only as authorized by orders issued in accordance with Clause II.A.7, FAR 52.216-18, Ordering (Oct 1995). The Contractor shall furnish to the Government, when and if ordered, the supplies or services specified in the Schedule up to and including the quantity designated in the Schedule as the "maximum." The Government shall order at least the quantity of supplies or services designated in the Schedule as the "minimum."
* edit: Dragon and Cygnus have dissimilar capabilities--they only share pressurized up-mass capability--so not all task orders will be competed...
| Dragon | Cygnus |
Pressurized up | yes | yes |
Pressurized down | yes | no |
Pressurized disposal | no | yes |
Unpressurized disposal | yes | no |
Unpressurized up | yes | no |
Unpressurized down | no | no |
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Some notes from a presentation today:
-1.1 qualification tank on structural stand in Texas will be rebuilt as next Grasshopper, with flight-like landing legs
-First 1.1 vehicle ships from Hawthorne to Texas late March
-After separation during its first launch, the 1.1 first stage will flip around using cold gas thrusters, and relight its engine to reenter more slowly. Then it will try to "land" on the ocean as practice for eventually landing back near the pad.
-Underground test stand in Texas is currently for FH only, but could change.
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Some notes from a presentation today:
-1.1 qualification tank on structural stand in Texas will be rebuilt as next Grasshopper, with flight-like landing legs
-First 1.1 vehicle ships from Hawthorne to Texas late March
-After separation during its first launch, the 1.1 first stage will flip around using cold gas thrusters, and relight its engine to reenter more slowly. Then it will try to "land" on the ocean as practice for eventually landing back near the pad.
-Underground test stand in Texas is currently for FH only, but could change.
Is there an audio or video recording of this presentation?
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Some notes from a presentation today:
-1.1 qualification tank on structural stand in Texas will be rebuilt as next Grasshopper, with flight-like landing legs
-First 1.1 vehicle ships from Hawthorne to Texas late March
-After separation during its first launch, the 1.1 first stage will flip around using cold gas thrusters, and relight its engine to reenter more slowly. Then it will try to "land" on the ocean as practice for eventually landing back near the pad.
-Underground test stand in Texas is currently for FH only, but could change.
Anything on the status of the second or third 1.1s, or how the 1.1 production rate is shaping up generally?
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Some notes from a presentation today:
-1.1 qualification tank on structural stand in Texas will be rebuilt as next Grasshopper, with flight-like landing legs
-First 1.1 vehicle ships from Hawthorne to Texas late March
-After separation during its first launch, the 1.1 first stage will flip around using cold gas thrusters, and relight its engine to reenter more slowly. Then it will try to "land" on the ocean as practice for eventually landing back near the pad.
-Underground test stand in Texas is currently for FH only, but could change.
Is there an audio or video recording of this presentation?
No, it was pretty informal. And 2552 - I didn't ask specifically, but see my post in the "where are the engines" thread.
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Some notes from a presentation today:
-1.1 qualification tank on structural stand in Texas will be rebuilt as next Grasshopper, with flight-like landing legs
-First 1.1 vehicle ships from Hawthorne to Texas late March
-After separation during its first launch, the 1.1 first stage will flip around using cold gas thrusters, and relight its engine to reenter more slowly. Then it will try to "land" on the ocean as practice for eventually landing back near the pad.
-Underground test stand in Texas is currently for FH only, but could change.
Woah, VERY informative (and great idea about "landing" on the water... I've thought about the same exact thing in a different context). Answers a lot of speculation. Pretty crazy they're going to be testing reuse techniques on the /first/ v1.1 flight! That should be pretty soon!
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Some notes from a presentation today:
-1.1 qualification tank on structural stand in Texas will be rebuilt as next Grasshopper, with flight-like landing legs
-First 1.1 vehicle ships from Hawthorne to Texas late March
-After separation during its first launch, the 1.1 first stage will flip around using cold gas thrusters, and relight its engine to reenter more slowly. Then it will try to "land" on the ocean as practice for eventually landing back near the pad.
-Underground test stand in Texas is currently for FH only, but could change.
Is there an audio or video recording of this presentation?
No, it was pretty informal. And 2552 - I didn't ask specifically, but see my post in the "where are the engines" thread.
Who gave the presentation?
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Some notes from a presentation today:
-1.1 qualification tank on structural stand in Texas will be rebuilt as next Grasshopper, with flight-like landing legs
-First 1.1 vehicle ships from Hawthorne to Texas late March
-After separation during its first launch, the 1.1 first stage will flip around using cold gas thrusters, and relight its engine to reenter more slowly. Then it will try to "land" on the ocean as practice for eventually landing back near the pad.
-Underground test stand in Texas is currently for FH only, but could change.
Wow, awesome! I hope they will share data on how well the reusability test of 1.1 goes.
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Very interesting about the testing on the next flight, in addition to the existing and next Grasshopper... This is going along faster than I had thought, I think they're kind of counting on this working... (They do seem to be doing the requisite testing with Grasshopper this time.)
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Some notes from a presentation today:
-1.1 qualification tank on structural stand in Texas will be rebuilt as next Grasshopper, with flight-like landing legs
-First 1.1 vehicle ships from Hawthorne to Texas late March
-After separation during its first launch, the 1.1 first stage will flip around using cold gas thrusters, and relight its engine to reenter more slowly. Then it will try to "land" on the ocean as practice for eventually landing back near the pad.
-Underground test stand in Texas is currently for FH only, but could change.
Very cool! The anticipation is growing for the maiden v1.1 flight! :o ;D
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Some notes from a presentation today:
-1.1 qualification tank on structural stand in Texas will be rebuilt as next Grasshopper, with flight-like landing legs
-First 1.1 vehicle ships from Hawthorne to Texas late March
-After separation during its first launch, the 1.1 first stage will flip around using cold gas thrusters, and relight its engine to reenter more slowly. Then it will try to "land" on the ocean as practice for eventually landing back near the pad.
-Underground test stand in Texas is currently for FH only, but could change.
Presentation by whom? If this is substantiated, I think a bunch of us are owed about 5 gallons of cool-aid :)
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Pretty crazy they're going to be testing reuse techniques on the /first/ v1.1 flight! That should be pretty soon!
Hmm? Crazy? Didn't they test reuse techniques on the first v1.0 flight? Of course those were different techniques.... ;)
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Pretty crazy they're going to be testing reuse techniques on the /first/ v1.1 flight! That should be pretty soon!
Hmm? Crazy? Didn't they test reuse techniques on the first v1.0 flight? Of course those were different techniques.... ;)
I guess I meant surprising and unexpected, not more crazy than they were in the past...
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Some notes from a presentation today:
-After separation during its first launch, the 1.1 first stage will flip around using cold gas thrusters, and relight its engine to reenter more slowly. Then it will try to "land" on the ocean as practice for eventually landing back near the pad.
Honestly, not a big surprise for me.
http://forum.nasaspaceflight.com/index.php?topic=30350.msg996323#msg996323
And Jim's hints made me assured.
BTW: Thanks Jason !
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-After separation during its first launch, the 1.1 first stage will flip around using cold gas thrusters, and relight its engine to reenter more slowly. Then it will try to "land" on the ocean as practice for eventually landing back near the pad.
Any word on whether the only recovery mechanism will be propulsion, or whether the cork and/or parachutes will be making a return? I'm guessing it's the former, but the latter would be nice. Do they count on recovering more than just recognisable wreckage? I'm guessing they don't.
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Recovering *anything* will be a huge step forward. Then they can move on from there.
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Agreed, but they already have the cork and the parachutes, so a guy can hope...
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I think the idea is to simulate a real landing on the water - a parachute will not be helpful in that regard. As for TPS, they certainly have margin on that flight, but we'll have to wait and see.
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Once you kill your horizontal velocity you don't need TPS.
And a good propulsive landing has less residual speed than parachute.
I think that, for the first trial, they would be very happy to recover some recognizable wreckage.
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This is exciting stuff. Even if they just demonstrate first stage turn around and relight that will be a big step forward. Anything extra would be a bonus.
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Agreed with all your points, but if they did manage to recover the stage in the way they originally intended + some propulsion, then that would be an enormous breakthrough. But hey, I'll be happy with just recognisable wreckage.
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So this experiment is going to be performed on the next flight? The first flight of v1.1? Nice.
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Then it will try to "land" on the ocean as practice for eventually landing back near the pad.
Will it float?
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Then it will try to "land" on the ocean as practice for eventually landing back near the pad.
Will it float?
Likely.
Over 400 m3 of tanks for a dry weight around 20 t.
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Then it will try to "land" on the ocean as practice for eventually landing back near the pad.
Will it float?
Likely.
Over 400 m3 of tanks for a dry weight around 20 t.
If it survives the turn-around and descent (the previous F9 v.1.0 stages were torn apart by aerodynamic forces, IIRC), the final contact with the ocean's surface will be slower than a parachute descent. Apart from flash-cooling and salt-water damage to the engines, the stage would then be recovered near-intact. That alone will make some SpaceX structural engineers delirious with glee - they'll get to tear apart a flight article core and determine exactly what stresses it suffers and therefore what needs to be done to make it reusable.
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Then it will try to "land" on the ocean as practice for eventually landing back near the pad.
Will it float?
Likely.
Over 400 m3 of tanks for a dry weight around 20 t.
depends on how intact it comes down, and whether it lets in water- through either engines or a hard landing.
So yes, it will float- question is for how long.
another question is how structurally sound the empty stage is when floating on an angle, partially submerged and with some amount of fuels left and boiling off..
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I wonder how they are going to monitor the "landing". The "impact" point likely will be over the horizon from any VAFB tracking assets and also, don't want to use assets still tracking the upperstage? TDRS? but that may require two satellites. Renting some land on Palos Verde and put their own dish there? Still might have the over the horizon issue.
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How about the approach they used on one of the early flights - a boat in the expected drop zone and then they either recover the stage if it survives or one of those fancy talon pods, i.e. possibly no live telemetry during splashdown?
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Article on LWN about SpaceX's avionics software development process and software stack:
http://lwn.net/SubscriberLink/540368/29c72913b4ab8016/
Main point is that Falcon/Dragon avionics are both now fully Linux-based.
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Also good to hear that they're deeply into automation: unit testing, build server, static analysis, build status monitoring etc.
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-Underground test stand in Texas is currently for FH only, but could change.
So we can assume that they are going to test the F9 v1.1 stages on the same test stand that was peviously used for the 1.0 stages?
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-Underground test stand in Texas is currently for FH only, but could change.
So we can assume that they are going to test the F9 v1.1 stages on the same test stand that was peviously used for the 1.0 stages?
Yes, and as already pointed out by someone, you can actually see the "umbilical" tower on VTS-3 has also been extended similar to the structural test stand. See here: http://www.flickr.com/photos/jimntexas/8506121798/in/photostream
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Article on LWN about SpaceX's avionics software development process and software stack:
http://lwn.net/SubscriberLink/540368/29c72913b4ab8016/
Main point is that Falcon/Dragon avionics are both now fully Linux-based.
I think the main point is that their working procedures and logging/replay strategy is very good.
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Article on LWN about SpaceX's avionics software development process and software stack:
http://lwn.net/SubscriberLink/540368/29c72913b4ab8016/
Main point is that Falcon/Dragon avionics are both now fully Linux-based.
hmm. I'm not sure whether LWN will like you publishing a subscriber link in an open forum.. the article will be free in a couple of weeks.
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There are two penguin enforcers outside my door even now, wearing dark suits, and shifting their weight side to side in a very intimidating manner.
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Article on LWN about SpaceX's avionics software development process and software stack:
http://lwn.net/SubscriberLink/540368/29c72913b4ab8016/
Main point is that Falcon/Dragon avionics are both now fully Linux-based.
hmm. I'm not sure whether LWN will like you publishing a subscriber link in an open forum.. the article will be free in a couple of weeks.
The LWN FAQ says:
Where is it appropriate to post a subscriber link?
Almost anywhere. Private mail, messages to project mailing lists, and blog entries are all appropriate. As long as people do not use subscriber links as a way to defeat our attempts to gain subscribers, we are happy to see them shared.
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I wonder how they are going to monitor the "landing". The "impact" point likely will be over the horizon from any VAFB tracking assets and also, don't want to use assets still tracking the upperstage? TDRS? but that may require two satellites. Renting some land on Palos Verde and put their own dish there? Still might have the over the horizon issue.
Presumably they'll have some boat near the expected impact/landing point, that can document but also recover what is left. It will be interesting to see the NOTAM area for this excercise.
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Article on LWN about SpaceX's avionics software development process and software stack:
http://lwn.net/SubscriberLink/540368/29c72913b4ab8016/
Main point is that Falcon/Dragon avionics are both now fully Linux-based.
hmm. I'm not sure whether LWN will like you publishing a subscriber link in an open forum.. the article will be free in a couple of weeks.
To the contrary, this is exactly how the subscriber link feature is intended to be used! :)
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Very exciting information in the SpaceX general section forum today.
Not a single post in the missions section so far today and Dragon is on orbit.
SpaceX have an uncanny ability to get people thinking/excited about whats next.
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Apart from flash-cooling and salt-water damage to the engines, the stage would then be recovered near-intact. That alone will make some SpaceX structural engineers delirious with glee - they'll get to tear apart a flight article core and determine exactly what stresses it suffers and therefore what needs to be done to make it reusable.
I don't know, you will have a vertical stage that will fall over, and has LOX in it.
It is very possible that when the engine cuts it will fall over with enough force to rupture the tanks. The boiling LOX will make the stage hazardous to approach until it completely vents.
My two cents if you want to try to recover the stage is to hover until you are out of LOX and hope enough of the stage survives the fall to stay afloat.
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LOx is going to boil off pretty darned quick once the stage hits the water.
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My two cents if you want to try to recover the stage is to hover until you are out of LOX and hope enough of the stage survives the fall to stay afloat.
Except that the stage won't be able to hover with empty tanks, Merlin thrust is too high, assuming the known 30% throttle.
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Apart from flash-cooling and salt-water damage to the engines, the stage would then be recovered near-intact. That alone will make some SpaceX structural engineers delirious with glee - they'll get to tear apart a flight article core and determine exactly what stresses it suffers and therefore what needs to be done to make it reusable.
I don't know, you will have a vertical stage that will fall over, and has LOX in it.
It is very possible that when the engine cuts it will fall over with enough force to rupture the tanks. The boiling LOX will make the stage hazardous to approach until it completely vents.
My two cents if you want to try to recover the stage is to hover until you are out of LOX and hope enough of the stage survives the fall to stay afloat.
Dumping the LOX is an important issue that may prove a problem. But if the pseudo-landing is a success, then entry to the ocean could be quite gentle - straight down and only toppling once half-submerged, so a gradual loading, perhaps not hugely more than the horizontal configuration for commissioning.
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Sorry, from the above mentioned LWN article, I found this too funny (my bold):
When the build fails, it should "fail loudly" with a "monitor that starts flashing red" and email to everyone on the team. When that happens, you should "respond immediately" to fix the problem. In his team, they have a full-size Justin Bieber cutout that gets placed facing the team member who broke the build. They found that "100% of software engineers don't like Justin Bieber", and will work quickly to fix the build problem.
This is technical but has been discussed to death (and I was on the other fence). So I gotta admit this is humbling.
His team does not use "off-the-shelf distro kernels". Instead, they spend a lot of time evaluating kernels for their needs. One of the areas they focus on is scheduler performance. They do not have hard realtime requirements, but do care about wakeup latencies, he said. There are tests they use to quantify the performance of the scheduler under different scenarios, such as while stressing the network. Once a kernel is chosen, "we try not to change it".
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My two cents if you want to try to recover the stage is to hover until you are out of LOX and hope enough of the stage survives the fall to stay afloat.
Except that the stage won't be able to hover with empty tanks, Merlin thrust is too high, assuming the known 30% throttle.
Source for just 30% throttle figure?
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Dumping the LOX is an important issue that may prove a problem. But if the pseudo-landing is a success, then entry to the ocean could be quite gentle - straight down and only toppling once half-submerged, so a gradual loading, perhaps not hugely more than the horizontal configuration for commissioning.
I'm not sure it would topple at all, rather it should float upright with the engines submerged. The center of gravity will be quite low with empty tanks, afterall. Ofcourse if it comes apart, all bets are off.
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Source for just 30% throttle figure?
Saw it mentioned countless times here on the forum.
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Source for just 30% throttle figure?
Saw it mentioned countless times here on the forum.
I thought it was a 30% throttle range, from 70-100.
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I thought it was a 30% throttle range, from 70-100.
Right, that is what 30% throttle means, up to 30% down from nominal. At least that is how I understand it.
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Source for just 30% throttle figure?
Saw it mentioned countless times here on the forum.
I thought it was a 30% throttle range, from 70-100.
That is an old figure, for just v1.0 Merlin Vac. If that's the source, then it's outdated and no longer applies.
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Fix yer' quotes!
Sorry, did it already.
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If that's the source, then it's outdated and no longer applies.
OK, I'll bite. What does apply, because Tom Mueller originally reported M1D to also be in that throttle range?
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Anyone have a clue where the first stage reentry point would be or take a best guess launching from Vandenburg, California.
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If that's the source, then it's outdated and no longer applies.
OK, I'll bite. What does apply, because Tom Mueller originally reported M1D to also be in that throttle range?
Show the source.
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Source for just 30% throttle figure?
Saw it mentioned countless times here on the forum.
I thought it was a 30% throttle range, from 70-100.
That is an old figure, for just v1.0 Merlin Vac. If that's the source, then it's outdated and no longer applies.
Are you sure? It was mentioned all the time on the Grasshopper thread. And that is a Merlin 1D.
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Somebody that know more about turbopumps and engines can answer this question. We "know":
1) That Merlin 1D can throttle from 100% to 70%.
2) Merlin 1D Vac will use the same turbopump as 1D.
Can we then assume that Merlin 1D Vac will only be able to throttle 100% to 70%?
Why this question? Because if they could do it, they might use a Vac without extension on the center engine. On the one hard they will have to restart it, thus, that's expected. But the second thing is that they channel the GG exhaust to the nozzle. This might help (with a SL optimized extension) with instabilities at low throttle point at sea level.
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If that's the source, then it's outdated and no longer applies.
OK, I'll bite. What does apply, because Tom Mueller originally reported M1D to also be in that throttle range?
Show the source.
I think it's you who should show the source that it does NOT apply. So show the source.
I have better things to do than chasing references for your convenience while your remarks are supposed to go unchallenged.
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I'm not sure it would topple at all, rather it should float upright with the engines submerged. The center of gravity will be quite low with empty tanks, afterall. Ofcourse if it comes apart, all bets are off.
It's not going to float upright, the stage is long and CG not so close to the bottom.
It will float inclined with two or three engines submerged.
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Somebody that know more about turbopumps and engines can answer this question. We "know":
1) That Merlin 1D can throttle from 100% to 70%.
2) Merlin 1D Vac will use the same turbopump as 1D.
Can we then assume that Merlin 1D Vac will only be able to throttle 100% to 70%?
Why this question? Because if they could do it, they might use a Vac without extension on the center engine.
I think that with the (assumed) commonality between M1D and M1DVac, an M1DVac without nozzle extension... would basically be an M1D. :D Not quite... But what would be the point?
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If that's the source, then it's outdated and no longer applies.
OK, I'll bite. What does apply, because Tom Mueller originally reported M1D to also be in that throttle range?
Show the source.
It was stated on the "SpaceX Unveils Plans To Be World’s Top Rocket Maker" article on Aviation Week and Space Technology. Regrettably now it requires a subscription. Enough proof or do you also need a subscription?
BTW, it's stated on an article of this very site here:
http://www.nasaspaceflight.com/2012/06/spacex-merlin-1d-orbital-fire-aj-26-engine/ (http://www.nasaspaceflight.com/2012/06/spacex-merlin-1d-orbital-fire-aj-26-engine/)
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Somebody that know more about turbopumps and engines can answer this question. We "know":
1) That Merlin 1D can throttle from 100% to 70%.
2) Merlin 1D Vac will use the same turbopump as 1D.
Can we then assume that Merlin 1D Vac will only be able to throttle 100% to 70%?
Why this question? Because if they could do it, they might use a Vac without extension on the center engine.
I think that with the (assumed) commonality between M1D and M1DVac, an M1DVac without nozzle extension... would basically be an M1D. :D Not quite... But what would be the point?
The channeling of the turbopump is different. I ignore if they could do something to increase the throttle point on the Vac. That was my technical question.
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If that's the source, then it's outdated and no longer applies.
OK, I'll bite. What does apply, because Tom Mueller originally reported M1D to also be in that throttle range?
Show the source.
I think it's you who should show the source that it does NOT apply. So show the source.
I have better things to do than chasing references for your convenience while your remarks are supposed to go unchallenged.
It's common sense that says you're not going to be doing a heck of a lot of stable hovering if you only can throttle from 70-100%! You need to have a high throttle range or your control authority is going to be limited so much that your flight will be unstable. And yet, they've already done so with Grasshopper.
I am confident there's better throttle range for the center engine Merlin 1D, even if the outer ones might not throttle as much (perhaps because the center engine would have a slightly shorter nozzle, preventing flow separation).
I will /bet/ someone that the center engine of Grasshopper has better than a 70-100% throttle range.
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Somebody that know more about turbopumps and engines can answer this question. We "know":
1) That Merlin 1D can throttle from 100% to 70%.
2) Merlin 1D Vac will use the same turbopump as 1D.
Can we then assume that Merlin 1D Vac will only be able to throttle 100% to 70%?
Why this question? Because if they could do it, they might use a Vac without extension on the center engine. On the one hard they will have to restart it, thus, that's expected. But the second thing is that they channel the GG exhaust to the nozzle. This might help (with a SL optimized extension) with instabilities at low throttle point at sea level.
1) What? Really? I was under the impression this was a 100% to 30% throttle.
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No... While the true throttling range may be more (it is proprietary/secret), the official word is a 70-100% throttling range.
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No... While the true throttling range may be more (it is proprietary/secret), the official word is a 70-100% throttling range.
Official where?
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No... While the true throttling range may be more (it is proprietary/secret), the official word is a 70-100% throttling range.
Official where?
I mean what the press have been told. You can ask Chris what the source was for this article: http://www.nasaspaceflight.com/2012/06/spacex-merlin-1d-orbital-fire-aj-26-engine/
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No... While the true throttling range may be more (it is proprietary/secret), the official word is a 70-100% throttling range.
Official where?
I mean what the press have been told. You can ask Chris what the source was for this article: http://www.nasaspaceflight.com/2012/06/spacex-merlin-1d-orbital-fire-aj-26-engine/
Thank you. That is the throttle range of all the engines, nothing says the engine being used for landing (i.e. the one on Grasshopper) won't have a better throttle range. It'd be really weird if SpaceX chose to limit themselves to just 70-100% throttling for landing. I highly, highly doubt it.
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In the presentation that prompted all of this discussion, they said that the reusable first stage has too high T/W to hover at all.
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How about the approach they used on one of the early flights - a boat in the expected drop zone and then they either recover the stage if it survives or one of those fancy talon pods, i.e. possibly no live telemetry during splashdown?
Too many things could go wrong. To be a useful test, I think you need live telemetry.
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In the presentation that prompted all of this discussion, they said that the reusable first stage has too high T/W to hover at all.
The heck? So they ARE planning on sticking the landing. Wow that is going to be an impressive landing! This is mind boggling.
Edit: Jeez people are posting fast on this forum. We're getting to a new page every 15-30 minutes at the current rate.
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In the presentation that prompted all of this discussion, they said that the reusable first stage has too high T/W to hover at all.
Okay, looks like I may be wrong, then (still think it's not 70-100%, though...). Thanks.
Too bad no one took up my bet! ;)
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It's common sense that says you're not going to be doing a heck of a lot of stable hovering if you only can throttle from 70-100%!
You can't hover, but it's not necessarily the case that you need or even want to hover, due to gravity losses it's optimal if you land at full throttle. I imagine they'll come in at some throttle point that gives them plenty of room on either side to adjust.
Landing requires that the speed is survivable when the stage reaches the ground, it doesn't require hovering.
And yet, they've already done so with Grasshopper.
Grasshopper is ballasted.
I am confident there's better throttle range for the center engine Merlin 1D, even if the outer ones might not throttle as much (perhaps because the center engine would have a slightly shorter nozzle, preventing flow separation).
Seems like that would sacrifice performance and increase gravity losses, particularly during landing.
If it can be done without this measure, it should be.
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About throttling: Merlins have good potential for deep throttling due to pintle injector design (LEM descent engine used it too), but it requires a moving pintle, dunno if current Merlins have it, unlikely with just 70%-100% range. Throttling is less turbopump issue but more about maintaining adequate injector drop (for combustion/injection stability) while flow rate decreases. To achieve that you need to constrict your injector orifices, easier with pintle because you have only two.
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Some notes from a presentation today:
-1.1 qualification tank on structural stand in Texas will be rebuilt as next Grasshopper, with flight-like landing legs
-First 1.1 vehicle ships from Hawthorne to Texas late March
-After separation during its first launch, the 1.1 first stage will flip around using cold gas thrusters, and relight its engine to reenter more slowly. Then it will try to "land" on the ocean as practice for eventually landing back near the pad.
-Underground test stand in Texas is currently for FH only, but could change.
Where, when and what presentation and by whom? Where there any slides, recordings done of the presentation?
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Some notes from a presentation today:
-1.1 qualification tank on structural stand in Texas will be rebuilt as next Grasshopper, with flight-like landing legs
-First 1.1 vehicle ships from Hawthorne to Texas late March
-After separation during its first launch, the 1.1 first stage will flip around using cold gas thrusters, and relight its engine to reenter more slowly. Then it will try to "land" on the ocean as practice for eventually landing back near the pad.
-Underground test stand in Texas is currently for FH only, but could change.
Where, when and what presentation and by whom? Where there any slides, recordings done of the presentation?
Is there an audio or video recording of this presentation?
No, it was pretty informal. And 2552 - I didn't ask specifically, but see my post in the "where are the engines" thread.
The presentation was given by three employees from the propulsion and manufacturing divisions. It was mostly about interning at SpaceX, but they took technical questions too.
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Just so we're on the same page, we are talking about just the first stage, right?
1. Just the center engine would be used for landing. The other eight serve as ballast.
2. M1D-Vac only applies to the second stage, which is presumably in orbit and not trying to land.
This configuration seems to be very similar to Grasshopper in terms of mass and COG, so they probably know that the stage can hover. However, without the numerical details, we can't be totally sure that Grasshopper is a good substitute for the first stage. Still, it seems like they could be simulating an F9-1.1 stage with Grasshopper and would have high confidence they can make it work.
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I tried to resume in a simple graph the info we have on Grasshopper flight regarding thrust to weight.
We know that M1D has a SL thrust of 650 kN and a propellant flow of 230 kg/s (100%)
To take off we need a T/W higher than 1.
To land without relight we need a T/W lower than 1
Plotting the actual mass (take-off mass less propellant flow, lower line 100% flow, upper line min throttle flow) and the minimum mass (assuming as minimum mass Tmin/0.9) I get the following diagrams:
First case take off T/W 1.2 min throttle 70%
Second case take off T/W 1.1 min throttle 70%
Third case take off T/W 1.2 min throttle 60%
Grasshopper's december flight lasted about 30 seconds, so first plot data are out of range.
Third plot shows that with 60% throttle SpaceX has lot of margin to do other hovering tests
Second plot show that with 70% throttle the only way to push the envelope is stick the landing.
Obviously an assumptions of the plots is slow motion, perhaps compatible with first Grasshopper hops.
About plots: X=seconds - Y=kg - Upper sloped line=mass at minimum flow - Lower sloped line=mass at maximum flow - Flat line=minimum mass threshold
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Grasshopper and Falcon 9 v1.1 shouldn't be compared directly in the way people are doing. They are substantially different vehicles.
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Grasshopper and Falcon 9 v1.1 shouldn't be compared directly in the way people are doing. They are substantially different vehicles.
The next Grasshopper will be very, very similar to v1.1. It will be made from the v1.1 qualification tank.
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Grasshopper and Falcon 9 v1.1 shouldn't be compared directly in the way people are doing. They are substantially different vehicles.
My only intention was to show that we will see soon if SpaceX is going to stick the landing on Grasshopper, and this will go directly into v1.1 landing.
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Grasshopper and Falcon 9 v1.1 shouldn't be compared directly in the way people are doing. They are substantially different vehicles.
The next Grasshopper will be very, very similar to v1.1. It will be made from the v1.1 qualification tank.
Yes, but we have no examples of it flying which people are generating numbers from. We don't even have solid numbers on the dry weight of Falcon 9 v1.1 for calculating T/W.
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We know that the Grasshopper can throttle below hover thrust. (We've seen videos of it doing so.) What we don't know is how much ballast it is carrying. I doubt the ballast is in the form of excess fuel as that would create quite a hazard in case of any kind of accident causing a fuel tank rupture.
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We know that the Grasshopper can throttle below hover thrust. (We've seen videos of it doing so.) What we don't know is how much ballast it is carrying. I doubt the ballast is in the form of excess fuel as that would create quite a hazard in case of any kind of accident causing a fuel tank rupture.
Indeed. It will be interesting once they remove all the ballast and we get to see demonstrations of landing sticks, if that is indeed the plan.
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We know that the Grasshopper can throttle below hover thrust. (We've seen videos of it doing so.) What we don't know is how much ballast it is carrying. I doubt the ballast is in the form of excess fuel as that would create quite a hazard in case of any kind of accident causing a fuel tank rupture.
Per the EPA environmental assessment:
"The Grasshopper RLV has a maximum operational propellant load of approximately 6,900 gallons; however, the propellant loads for any one test would often be lower than the maximum propellant load. Even when the maximum propellant load is used, the majority of the propellant would remain unburned and would serve as ballast to keep the thrust-to-weight ratio low."
So...they're ballasting with fuel.
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I doubt the ballast is in the form of excess fuel as that would create quite a hazard in case of any kind of accident causing a fuel tank rupture.
I think a lot of it is fuel. There's also the indestructible landing gear.
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LOx is going to boil off pretty darned quick once the stage hits the water.
LOX boiling off in water will cause the water to freeze. There is a risk that the rocket stage will turn into an iceberg.
Do you think that Titanic is a good name for the recovery ship? :-\ ::)
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How about a chase plane?
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I was tipped by somebody else that the new April 2013 issue of Popular Mechanics has a large Falcon feature that includes a nice 3D illustration of the Merlin 1D and a 2 page Falcon Heavy illustration. Maybe someone here can check out how they look like? ;)
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I wonder how they are going to monitor the "landing". The "impact" point likely will be over the horizon from any VAFB tracking assets and also, don't want to use assets still tracking the upperstage? TDRS? but that may require two satellites. Renting some land on Palos Verde and put their own dish there? Still might have the over the horizon issue.
SpaceX has quite a few different satellite communications providers on its launch manifest. Maybe it could give one of them a launch discount in return for telemetry transfer? The whole mach 9 thing is likely to confuse some of the networks, but maybe one of them would work? Many of the networks are designed to work with mach 0.8 airplanes, for which mach 9 is only an order of magnitude faster than usual.
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I wonder how they are going to monitor the "landing". The "impact" point likely will be over the horizon from any VAFB tracking assets and also, don't want to use assets still tracking the upperstage? TDRS? but that may require two satellites. Renting some land on Palos Verde and put their own dish there? Still might have the over the horizon issue.
SpaceX has quite a few different satellite communications providers on its launch manifest. Maybe it could give one of them a launch discount in return for telemetry transfer? The whole mach 9 thing is likely to confuse some of the networks, but maybe one of them would work? Many of the networks are designed to work with mach 0.8 airplanes, for which mach 9 is only an order of magnitude faster than usual.
Normal communication satellites cannot handle such rocket to ground telemetry transfers (or else why build TDRS?).....
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Normal communication satellites cannot handle such rocket to ground telemetry transfers (or else why build TDRS?).....
Is the problem excessive speed, excessive altitude, or something else?
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I was tipped by somebody else that the new April 2013 issue of Popular Mechanics has a large Falcon feature that includes a nice 3D illustration of the Merlin 1D and a 2 page Falcon Heavy illustration. Maybe someone here can check out how they look like? ;)
Yep, just got it today in the mail. Typical PM, short, basic info with a graphic that is , I'm sure, their interpretation of what it will look like. Nice looking graphic anyways.
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I was tipped by somebody else that the new April 2013 issue of Popular Mechanics has a large Falcon feature that includes a nice 3D illustration of the Merlin 1D and a 2 page Falcon Heavy illustration. Maybe someone here can check out how they look like? ;)
Yep, just got it today in the mail. Typical PM, short, basic info with a graphic that is , I'm sure, their interpretation of what it will look like. Nice looking graphic anyways.
RT @PopSci http://www.kollected.com/Next
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I wonder how they are going to monitor the "landing". The "impact" point likely will be over the horizon from any VAFB tracking assets and also, don't want to use assets still tracking the upperstage? TDRS? but that may require two satellites. Renting some land on Palos Verde and put their own dish there? Still might have the over the horizon issue.
SpaceX has quite a few different satellite communications providers on its launch manifest.
What are the size of the dishes that send data to the comsat? Also they aren't moving.
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I'm not sure what bandwidth we're talking about, but there are plenty of S-band satellites that have large enough footprints so horizontal speed wouldn't be a problem if you reserved that transponder for dedicated use at the time. They can also be set for wide range AFC that was made for cheap VSAT oscillators, but can also account for doppler shift to handle vertical speed. Some work with very low gain antennas that don't need precise pointing.
If you want shipboard relay, boats everywhere have 1.2M ku-band dishes that do 3mbs up and down.
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I'm not sure what bandwidth we're talking about, but there are plenty of S-band satellites that have large enough footprints so horizontal speed wouldn't be a problem if you reserved that transponder for dedicated use at the time. They can also be set for wide range AFC that was made for cheap VSAT oscillators, but can also account for doppler shift to handle vertical speed. Some work with very low gain antennas that don't need precise pointing.
If you want shipboard relay, boats everywhere have 1.2M ku-band dishes that do 3mbs up and down.
That is my point, launch vehicles don't have dishes, they have omni antennas
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That is my point, launch vehicles don't have dishes, they have omni antennas
Handheld satellite phones don't have dishes either:
http://www.satellitephonestore.com/catalog/phones-terminals
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That is my point, launch vehicles don't have dishes, they have omni antennas
Handheld satellite phones don't have dishes either:
http://www.satellitephonestore.com/catalog/phones-terminals
I think they tried an Iridium link on one of the early F1s. They're basic channel is only 2400bps and there are a lot of handoffs that can cause glitches and disconnection. They claim higher speeds, but I doubt if compression is going to be any good on a telemetry stream, so all they could do would be combined carriers.
The bgan type is one of the ones I referred to as using low gain s-band. But it's always shared uphill and could have problems with a fast moving remote end throwing the slot timing off. They were suppose to have high speed handheld s-band phones by now, but I haven't kept track of the Skyterra/TerraStar disasters in a few years.
What would Doppler shift be at the greatest speed relative to a satellite? Something like 10khz? I seem to remember radios that use the incoming carrier as their timebase and could adjust up to 20khz.
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That is my point, launch vehicles don't have dishes, they have omni antennas
Handheld satellite phones don't have dishes either:
They don't have the data rate
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They claim higher speeds, but I doubt if compression is going to be any good on a telemetry stream, so all they could do would be combined carriers.
Just on this specific point, I'd think a telemetry stream is very compressible by its very nature. (though a smart telemetry-optimized data format can reduce the bandwidth requirement by a huge amount)
The air force has very powerful comm-center type airplanes. If one of those is lurking downrange, it will have good coverage of the trajectory, right?
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I was tipped by somebody else that the new April 2013 issue of Popular Mechanics has a large Falcon feature that includes a nice 3D illustration of the Merlin 1D and a 2 page Falcon Heavy illustration. Maybe someone here can check out how they look like? ;)
Yep, just got it today in the mail. Typical PM, short, basic info with a graphic that is , I'm sure, their interpretation of what it will look like. Nice looking graphic anyways.
RT @PopSci http://www.kollected.com/Next
That's a lot of detail.
I'm looking at the actuation components - can some experienced hand here give their impression?
I see:
- Actuation on all gimbals, appears to be 2 DOF per each
- Short stroke actuators and a curious ring on the actuation rod
- Actuation on all the pump exhausts? The thin silver rods - they look like very thin pistons or very thick tie rods.
Also, and I'm sure this is a trivial question - what are the very coarse large concentric "ribs" inside the nozzles?
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RT @PopSci http://www.kollected.com/Next
That's a lot of detail.
Looking at the M1D render alone, it doesn't seem to fit the actual hardware. The GG exhaust pipe is M1C-like and angled to the left, while the production M1D units appear to have it shorter, fatter and not pointed to the side. Also, the pipe feeding fuel to the regen jacket follows the nozzle curvature instead of being a straight pipe as rendered here.
Take these graphics with a very large grain of salt.
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RT @PopSci http://www.kollected.com/Next
That's a lot of detail.
Looking at the M1D render alone, it doesn't seem to fit the actual hardware. The GG exhaust pipe is M1C-like and angled to the left, while the production M1D units appear to have it shorter, fatter and not pointed to the side. Also, the pipe feeding fuel to the regen jacket follows the nozzle curvature instead of being a straight pipe as rendered here.
Take these graphics with a very large grain of salt.
Agreed. The thrust structure above each engine chamber also is not the correct one we've seen in M1D test firings.
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yeah, I just took a look at the rest of the site.... Especially that silly building...
I think you're right. He did get the CAD data from SpaceX probably, but it is as you say, just not right.
Still - do these internal ribs ring any bells with anyone? They are on the inner surface of the nozzle - would there be any reason to mess with the flow there?
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what are the very coarse large concentric "ribs" inside the nozzles?
Artistic bovine excrement.
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Also in the illustration he has corner fairings. Why would these be necessary with the concentric engine arrangement?
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I distrust deeply these drawings.
About M1D:
the old quadrapods aren't on the engine anymore;
the humps in the nozzle are ABE (R7 trademark);
TPA exaust is different;
Actuators rods are shorter and with different attachment points on the TC;
About FH:
Why tic-tac-toe fairings?
Why the old thrust structure?
To my knowledge, LOX tank has no stringers (maybe on FH the center core is going to gain stringers in the LOX tank, but not the boosters)
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Also core/booster tanks are of the same length, AIUI boosters are going to have longer tanks?
Rigid struts running from TPA to quadrapod in 1A/1C fashion. If I have understood correctly in (latest?) 1D the TPA gimbals with the thrust assembly, enabling TPA exhaust to be ducted into nozzle (1D Mvac).
It's just a good modeller mashing something together based on googled imagery. Looks great and professional, visually very palatable for Joe 6Pack.
Why 1.0 rectangular fairing at the base, is that how it's going to be despite circular engine arrangement?
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LOx is going to boil off pretty darned quick once the stage hits the water.
LOX boiling off in water will cause the water to freeze. There is a risk that the rocket stage will turn into an iceberg.
Do you think that Titanic is a good name for the recovery ship? :-\ ::)
I think you misrepresent the latent heat and conductivity of water. There is no way a bunch of LOX boiling off, even several tons of it, will freeze any appreciable amount of water.
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Rigid struts running from TPA to quadrapod in 1A/1C fashion. If I have understood correctly in (latest?) 1D the TPA gimbals with the thrust assembly, enabling TPA exhaust to be ducted into nozzle (1D Mvac).
I think the first stage version does that too. At least that's what it looks like...
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Rigid struts running from TPA to quadrapod in 1A/1C fashion. If I have understood correctly in (latest?) 1D the TPA gimbals with the thrust assembly, enabling TPA exhaust to be ducted into nozzle (1D Mvac).
I think the first stage version does that too. At least that's what it looks like...
No, that's the fuel manifold.
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I stand corrected! Thanks.
What's the ring around the nozzle then?
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I stand corrected! Thanks.
What's the ring around the nozzle then?
The fuel manifold.
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What's the ring around the nozzle then?
The fuel manifold.
In other words it injects fuel into the nozzle regenerative coolant lines. Depending on design some or all starts flowing down towards the nozzle lip, make a u-turn there and then flows back up, past the manifold, all the way to the injector in the other end.
Here the latest 1D Mvac image, added descriptions of the manifolds. Compare to F-1.
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It's just a good modeller mashing something together based on googled imagery. Looks great and professional, visually very palatable for Joe 6Pack.
yes, lots of things wrong with it, but if he went out and modeled this himself based on pictures, he's a nut case. This is a LOT of work.
My guess is that engineering gave him assemblies from some lot branch of the revision tree, and he assembled things together himself.
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what are the very coarse large concentric "ribs" inside the nozzles?
Artistic bovine excrement.
But the pictures are so pretty.
It's a Popular Science/Mechanics tradition. I remember a good looking article they did on Masten. It would have been a lot better if they'd given it to Jon (back then) or someone for five minutes to check out, but the graphics were nice to look at.
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It's just a good modeller mashing something together based on googled imagery. Looks great and professional, visually very palatable for Joe 6Pack.
yes, lots of things wrong with it, but if he went out and modeled this himself based on pictures, he's a nut case. This is a LOT of work.
My guess is that engineering gave him assemblies from some lot branch of the revision tree, and he assembled things together himself.
Or more likely he gets paid a decent amount for the work.
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yes, lots of things wrong with it, but if he went out and modeled this himself based on pictures, he's a nut case. This is a LOT of work.
Check his other work http://www.kollected.com/About (http://www.kollected.com/About)
Mr. Kaloterakis' other work looks very impressive and the Falcon actually looks simpler than many of the other illustrations, most clearly pure fantasy.
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Yes, I'm forwarding that round building around, for kicks.
Everything that's wrong with the environmental movement today, captured in one concise picture :)
The F9 modeling work, with all the routing of pipes and wires, is very very intricate. If he did it all himself, I'm actually impressed somewhat, bovine excrement notwithstanding :)
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yes, lots of things wrong with it, but if he went out and modeled this himself based on pictures, he's a nut case. This is a LOT of work.
Check his other work http://www.kollected.com/About (http://www.kollected.com/About)
Mr. Kaloterakis' other work looks very impressive and the Falcon actually looks simpler than many of the other illustrations, most clearly pure fantasy.
Sort of a modern day Chesley Bonestell. It isn't the details that matter, it is the overall impression created by the artist. (If he tried to present accurate draftsman-like details, the details would probably change before he published anyway.)
- Ed Kyle
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These things are not that hard to do. I bet he had some references from photographs and simply filled in the blanks with imagination. This is an illustration and not a CAD drawing. It is meant to give people a general idea of the thing, not to provide a plan for manufacturing.
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Robert Bigelow -“Right now, I think everyone is very impressed with SpaceX,” Bigelow said. “SpaceX has done a tremendous job successfully. They need to be recognized as a very serious player, and a very serious asset to this country.”
"Bigelow Aerospace has two pricing options for its potential customers. One uses SpaceX rockets and capsules and the other offers rides by Boeing, which is developing a passenger spaceship, the CST-100, to fly on sister company ULA’s Atlas 5 rockets.
But Bigelow said a third option is evolving as well, one that may be the truest testament to SpaceX’s future: launching Boeing’s capsules on SpaceX Falcon 9 rockets".
-Any truth about the CST-100 launching on Falcon 9? I know it was an option but I thought Boeing was just throwing this out there.
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Lets put it this way.
Boeing chose Atlas V which belongs to Lockheed ahead of their own Delta IV.
Price is the only thing that's important.
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Lets put it this way.
Boeing chose Atlas V which belongs to Lockheed ahead of their own Delta IV.
Price is the only thing that's important.
ULA is owned by both now.
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In this CRS2 launch video at 43 minutes we see the 1st and 2nd stage separation. The first stage appears to stay in perfect position relative to the second stage for about 45 seconds or so before beginning a slow turn.
Is this typical of stage separation? Is the 1st stage completely passive at this point? If it is what forces start the rotation?
http://www.youtube.com/watch?v=APYsbN-_l0M
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In this CRS2 launch video at 43 minutes we see the 1st and 2nd stage separation. The first stage appears to stay in perfect position relative to the second stage for about 45 seconds or so before beginning a slow turn.
Is this typical of stage separation? Is the 1st stage completely passive at this point? If it is what forces start the rotation?
This is only my speculation, someone correct me if this seems incorrect.
In reality nothing is built exactly the same. There are tiny manufacturing differences in the pusher rods that separate the stages and the time in which they activate. This normally wouldn't be noticeable, but in the absence of any resistive forces this can be seen as a net force such that it causes a slight rotation in the stage.
Even if they were built exactly the same, other things are different like the exact center of mass not being aligned with the center of the vehicle or things like remnant fuel left in the lower stage impacting or sloshing against the tank sides.
Edit: I just actually watched the time you were talking about. (Oops.) That rotation would be caused by thrust from the startup of the upper stage engine.
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I can't rule that out, but the start of rotation is very sudden, and occurs much too late after second stage ignition, IMO.
I think this was a deliberate actuation.
Between now and June, we will have nothing to do but rehash old videos, huh.
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I can't rule that out, but the start of rotation is very sudden, and occurs much too late after second stage ignition, IMO.
I think this was a deliberate actuation.
Between now and June, we will have nothing to do but rehash old videos, huh.
Huh? You can petty easily see the upper stage initially veer to the right and thrust in that direction, then the stage also starts to rotate in the same direction. It's pretty obvious its a combination of the upper stage moving away and the thrust from the upper stage kicking into a rotation in that direction.
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Look at the other frame, where you have a nice bore sight onto the second stage.
The second stage lights up, and for the longest time stays dead on center. Then, after much longer than it would have taken the exhaust to reach the first stage, there's a very sharp start of motion.
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There would still be some aerodynamic forces at MECO, right? Nose cone jettison is not until some time later than this.
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Gas thruster trying the turnaround rotation (thrust x-seconds gives y-rotation rate)?
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You're welcome to fire off guesses, but realize how little information we're dealing with here. It's bad to draw any kind of conclusion over something that's so small and could be explained in several other ways or combinations of ways. Upper stage engine thrust, atmospheric effects, fuel slosh, confusion from inertial coordinate frames, are a few that come to mind.
Just watch out for Occam's razor.
Edit: One other idea that came to mind, initially the lower stage is in the upper stage's wake. As it slowly moves off, one side of the lower stage will feel aerodynamic drag stronger than the other side which will cause a sudden strong net torque.
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You're welcome to fire off guesses, but realize how little information we're dealing with here. It's bad to draw any kind of conclusion over something that's so small and could be explained in several other ways or combinations of ways. Upper stage engine thrust, atmospheric effects, fuel slosh, confusion from inertial coordinate frames, are a few that come to mind.
Just watch out for Occam's razor.
Agree, too little data, but guessing is fun.
My guess is a valve is released on the 1st stage to depressurization the tanks and vent the last of the helium to insure a complete breakup of the stage as it reenters.
If they are not wanting to recover the stages at time the last thing they need is a scrap company getting a intact motor off the ocean floor considering they don't use patents.
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You're welcome to fire off guesses, but realize how little information we're dealing with here. It's bad to draw any kind of conclusion over something that's so small and could be explained in several other ways or combinations of ways. Upper stage engine thrust, atmospheric effects, fuel slosh, confusion from inertial coordinate frames, are a few that come to mind.
Just watch out for Occam's razor.
Edit: One other idea that came to mind, initially the lower stage is in the upper stage's wake. As it slowly moves off, one side of the lower stage will feel aerodynamic drag stronger than the other side which will cause a sudden strong net torque.
Guesses, for sure, but Occam's not your side this time. The wake thing is especially contrived....
We also know that they were experimenting with methods to get the stages to not break up on re-entry - at some point someone suggested induced tumbling.
But, yes - those are pretty weak guesses.
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Gas thruster trying the turnaround rotation (thrust x-seconds gives y-rotation rate)?
Yes, that's what I'm think as well. Or a tank pressure release valve on one of the sides that induces rotation. This is happening to late to be MVac induced, I would think.
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It seems like once the first stage starts turning in any given direction, more area is exposed to the second stage wake, increasing the turn rate.
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It seems like once the first stage starts turning in any given direction, more area is exposed to the second stage wake, increasing the turn rate.
yup - and that didn't seem to happen. It looked like a one time impulse.
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Jim, it's tumbled in the same way every flight. I wouldn't be surprised if it was intentional via tank venting. Remember, this stage was originally supposed to be recovered. It can't be completely "dead" if there was a planned parachute deployment further down the line (even if the parachutes haven't been installed lately).
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If the stage started turning then stopped I might believe it. If someone can provide evidence that there were thrusters in the interstage I might believe it.
Until then, I look forward to the first flight of v1.1 to see how they really maneuver the first stage.
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it's tumbled in the same way every flight
No, this time the SEP was very clean and 1st stage took longer to start tumbling. mlindner's analysis (http://forum.nasaspaceflight.com/index.php?topic=30385.msg1024766#msg1024766) is good, lots of random factors here.
Compare CRS-2 and COTS-1 images ten seconds after stage separation:
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I think this was a deliberate actuation.
Huh? Grasping for straws. The stage was dead. Aerodynamics, second stage thrust, and residual thrust from the booster made it pitch over.
I'm not weighing into the argument one way or the other, but will just note that video showed the upper stage venting post-SECO, and not longitudinally. It looked to me as if this would have induced tumbling of the upper stage.
Assuming commonality between M1Vac and M1C, and general second / first stage design, would it be reasonable to assume the same venting from the first stage engines? (With the eight outer engines being arranged symmetrically, there would be little net thrust, but any discharge from the centre engine would be unbalanced.)
cheers, Martin
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Moving this discussion beyond the whole rotating lower stage. I noticed something during launch that I'm wondering if someone could identify.
http://www.youtube.com/watch?v=BqCELhkXtsY?t=55s
At 55 seconds in on the right image there is an extensive amount of what looks like venting. Is this simply condensation from the vehicle hitting the wet air or is it something coming from the vehicle?
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Is this simply condensation from the vehicle hitting the wet air
The duration and intensity of that means it's almost certainly vapor in the air condensing as air flows along the cold LOX tank skin. Falcon always appears to fly at a slight angle of attack at around that portion of flight so air will flow around and concentrate on the portion of the vehicle facing the ground. If there's also a slight pressure drop in that region (which an AoA could produce there), that would only help in causing condensation.
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Hi all,
First post, complete noob, please be kind. I searched but could not find anything on this topic
My Question, when Dragon is at the ISS, does NASA consider it an emergency escape craft for the astronauts?
Welcome to the forum!
The answer to your question is no. There was some talk about equipping the cargo version of the Dragon with replaceable foam seats so the astronauts could use it as an emergency escape vehicle but those plans never went ahead. The problem, as I understand it, is the Common Berthing Mechanism (CBM) used to connect the Dragon to the station requires power to unberth. As this is unlikely to be available in an emergency, the CBM isn't suitable.
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Even referring to those as "plans" grants too much dignity. It was spitballin', nothing further.
Well, it is SpaceX after all ;)
It takes a long time. Not suitable for emergency situations at all.
Yep. CBM isn't just a little bit unsuitable for emergency egress.. it's very unsuitable :)
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Thanks for moving to the correct thread.
I understand what you are saying about the lengthy time to disconnect and power needed.
It's fun to dream, especially about spacex dragon!
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I believe another reason is that at least one, maybe two astros, would have to stay behind to operate the robotic arm to move Dragon away from station.
The manned version of Dragon which will dock instead of berth will be available relatively soon, 2015 - 2016 That version of Dragon will be capable of acting as a lifeboat.
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I believe another reason is that at least one, maybe two astros, would have to stay behind to operate the robotic arm to move Dragon away from station.
The manned version of Dragon which will dock instead of berth will be available relatively soon, 2015 - 2016 That version of Dragon will be capable of acting as a lifeboat.
If it were needed, they could fit a Dragon with a docking port, life support and seats. Just the LAS would be missing.
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I believe another reason is that at least one, maybe two astros, would have to stay behind to operate the robotic arm to move Dragon away from station.
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Not that it really matters (this idea is sunk by many considerations), but you can control the arm from the ground...
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I believe another reason is that at least one, maybe two astros, would have to stay behind to operate the robotic arm to move Dragon away from station.
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Not that it really matters (this idea is sunk by many considerations), but you can control the arm from the ground...
I think the problem is that this procedure would still require a bunch of systems on the station to be operational (power, computers, comms with ground, etc.). A life boat should function even if the station is completely dead - the crew, with flashlights and oxygen masks, hand-operate mechanical hatches, undock and deorbit.
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I believe another reason is that at least one, maybe two astros, would have to stay behind to operate the robotic arm to move Dragon away from station.
The manned version of Dragon which will dock instead of berth will be available relatively soon, 2015 - 2016 That version of Dragon will be capable of acting as a lifeboat.
If it were needed, they could fit a Dragon with a docking port, life support and seats. Just the LAS would be missing.
None of those are small modifications and would affect Dragon's ability to transport cargo. You also forgot to mention ECLSS.
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I believe another reason is that at least one, maybe two astros, would have to stay behind to operate the robotic arm to move Dragon away from station.
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Not that it really matters (this idea is sunk by many considerations), but you can control the arm from the ground...
Preprogrammed arm movements can be, but capture/release cannot.
So why isn't the arm capable of autonomously grappling objects (like HTV, Dragon, Cygnus) and berthing them?
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If it were needed, they could fit a Dragon with a docking port, life support and seats. Just the LAS would be missing.
None of those are small modifications and would affect Dragon's ability to transport cargo. You also forgot to mention ECLSS.
The cargo Dragons would fly unmodified.
They may not be small modifications. But they are already part of what is planned for the manned Dragon, so not a big separate challenge. Just the most challenging and most difficult to prove part, the Super Dracos with LAS function would be omitted.
And I did mention life support, just did not use the expression ECLSS.
Edit: Fixed quote.
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If it were needed, they could fit a Dragon with a docking port, life support and seats. Just the LAS would be missing.
None of those are small modifications and would affect Dragon's ability to transport cargo. You also forgot to mention ECLSS.
The cargo Dragons would fly unmodified.
They may not be small modifications. But they are already part of what is planned for the manned Dragon, so not a big separate challenge. Just the most challenging and most difficult to prove part, the Super Dracos with LAS function would be omitted.
And I did mention life support, just did not use the expression ECLSS.
Are you proposing to modify it or not? The ISS is not yet equipped with the docking mechanisms planned to be used for Commercial Crew (they don't planned to be delivered until 2015). Filling the cargo variant with seats will affect much cargo you can place in it. Why would a spacecraft that launches unmanned require LAS?
And finally why waste resources trying to force the Dragon cargo variant to also serve as a lifeboat when DragonRider is planned to become operational shortly thereafter?
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Are you proposing to modify it or not? The ISS is not yet equipped with the docking mechanisms planned to be used for Commercial Crew (they don't planned to be delivered until 2015). Filling the cargo variant with seats will affect much cargo you can place in it. Why would a spacecraft that launches unmanned require LAS?
Fun fact, according to AvWeek[1]a cargo Dragon will carry the docking adapter to ISS that DragonRider will use :)
And finally why waste resources trying to force the Dragon cargo variant to also serve as a lifeboat when DragonRider is planned to become operational shortly thereafter?
I agree!
1 - here: http://www.aviationweek.com/Article.aspx?id=/article-xml/AW_06_04_2012_p34-463365.xml
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Are you proposing to modify it or not? The ISS is not yet equipped with the docking mechanisms planned to be used for Commercial Crew (they don't planned to be delivered until 2015). Filling the cargo variant with seats will affect much cargo you can place in it. Why would a spacecraft that launches unmanned require LAS?
And finally why waste resources trying to force the Dragon cargo variant to also serve as a lifeboat when DragonRider is planned to become operational shortly thereafter?
I have difficulties understanding how you can misinterpret my statements. It may be because I am not a native english speaker but don't think that is the reason.
I did not propose to make these changes. I said they could be done if required. I don't see a requirement at this point and agree that the timeframe for Manned Dragon is short enough that it will probably not be required.
It would be an early installment of the manned Dragon, without LAS. So not safe to launch crew but safe as a rescue vessel because Dragon already has a history of successful landings.
I am not talking about modifying Cargo Dragon. Cargo Dragon would fly unmodified.
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Are you proposing to modify it or not? The ISS is not yet equipped with the docking mechanisms planned to be used for Commercial Crew (they don't planned to be delivered until 2015). Filling the cargo variant with seats will affect much cargo you can place in it. Why would a spacecraft that launches unmanned require LAS?
And finally why waste resources trying to force the Dragon cargo variant to also serve as a lifeboat when DragonRider is planned to become operational shortly thereafter?
I have difficulties understanding how you can misinterpret my statements. It may be because I am not a native english speaker but don't think that is the reason.
I did not propose to make these changes. I said they could be done if required. I don't see a requirement at this point and agree that the timeframe for Manned Dragon is short enough that it will probably not be required.
It would be an early installment of the manned Dragon, without LAS. So not safe to launch crew but safe as a rescue vessel because Dragon already has a history of successful landings.
I am not talking about modifying Cargo Dragon. Cargo Dragon would fly unmodified.
Okay, now I think I know the message you are trying to convey.
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Okay, now I think I know the message you are trying to convey.
So is there any value in launching an unmanned DragonRider to ISS? (If, for example, the LAS was late)
I think it's an interesting thought exercise and it might be doable for not TOO much effort[1], but I'm not sure I see the value add in it.
1 - the big work item being docking, I think... unless it was supposed to be automated before, someone either has to remote control it, or it has to be berthed to the IDS with the arm, or something
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All this talk of emergency egress makes me want to go read 'Dragonfly' again. Good timing too. Was too young last time round.
Anyway, the speculation, and what happened aboard Mir got me wondering, is there any escape scenario involving all crew members egressing through EVA? [In case, the paths to the escape craft through the station are blocked off] Can people in Orlan/PLSS ingress Soyuz and then repressurise? Can Soyuz undock without ANY manual intervention (hatch closure etc.), and maintain structural integrity?
Would this be a possible design consideration for a crewed dragon, or any other capsule? It should be possible in the case of Orion..?
PS - For those who know it's not possible currently, ignore the rest of this post.
For others - here are some of the reasons why.
1) Simply not enough space inside the Soyuz(or Dragon for that matter) to fit 3 in (in their spacesuits), and then close the hatch. [This is ignoring the complexity of donning launch and re-entry suits since they can land in the same suits. the equipment might make it impossible to fit in the seats though.. I'm sure they can hack something once inside (literally if need be) - but they won't be able to get inside]
2) It's pretty dangerous moving around without a proper MMU (SAFER's contingency only). Especially considering that station might not have attitude control after whatever the emergency it was that caused this. (It'd very likely have to be structural failure - through impact/fire etc, because other emergencies wouldn't be such fast onset ones - and they'd do 'normal' escape)
3) Donning the suits is time consuming, and there'd be no time even for an ISLE N2 purge. They'd be running the risk of the bends.
4) Quest hatch has to be operational (Can this be done manually? Without power? Can't assume it'd be too hard, even with the suits, given the pressure difference. But again, I don't think it's big enough to fit everyone in suits. If it can repress, then that's something else.)
5) I don't know if there's anywhere to hold on to a Soyuz/Dragon and not get burned, when it undocks. I guess they COULD hold hands in a sort of triangle, and hug the heat shield, but that's just in Hollywood script zone now.
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is there any escape scenario involving all crew members egressing through EVA? [In case, the paths to the escape craft through the station are blocked off] Can people in Orlan/PLSS ingress Soyuz and then repressurise?
No.
Can Soyuz undock without ANY manual intervention (hatch closure etc.)
Not without the hatch being closed already. (manually)
But there are probably better threads to ask this in... (Q&A or ISS forum)
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... according to AvWeek (http://"http://www.aviationweek.com/Article.aspx?id=/article-xml/AW_06_04_2012_p34-463365.xml"), a cargo Dragon will carry the docking adapter to ISS that DragonRider will use :)
Do we know if this is the regular Dragon or the extended-Trunk Dragonphant?
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None of those are small modifications and would affect Dragon's ability to transport cargo. You also forgot to mention ECLSS.
Are these things really NEEDED in an emergency? Suppose there are 6 astronauts on the station and a Soyuz catches fire and they need to evacuate. So three folks pile into the as-is Dragon, the remaining three close the hatch and cast it free, then take the remaining Soyuz home. Do the folks in the Dragon survive?
I think they've got a decent chance, if they can land somewhere where folks can find them and let them out. You don't need food, water, toilets, etc. for just a few hours, and there should be enough air as well. Without power it probably gets cold, if anything, but that's OK for short while, and maybe they can grab some extra clothes on the way out. It would certainly be better to have seats, but if they lie down on the deck with their heads padded, the main shocks (parachute opening, water impact) might be survivable. Then someone has to find them and let them out. It's not fun, but in an emergency you take what you can get.
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None of those are small modifications and would affect Dragon's ability to transport cargo. You also forgot to mention ECLSS.
Are these things really NEEDED in an emergency? Suppose there are 6 astronauts on the station and a Soyuz catches fire and they need to evacuate. So three folks pile into the as-is Dragon, the remaining three close the hatch and cast it free, then take the remaining Soyuz home. Do the folks in the Dragon survive?
Simply put, the odds are against it. If they aren't fatally injured by the re-entry forces (5g+) in a cabin without any padding, let alone couches, the air will get stale very quickly, especially as it will take some time for the spacecraft to either get to a re-entry window close to a civilisation or for a rescue team to get to a randomly-splashed capsule.
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None of those are small modifications and would affect Dragon's ability to transport cargo. You also forgot to mention ECLSS.
Are these things really NEEDED in an emergency? Suppose there are 6 astronauts on the station and a Soyuz catches fire and they need to evacuate. So three folks pile into the as-is Dragon, the remaining three close the hatch and cast it free, then take the remaining Soyuz home. Do the folks in the Dragon survive?
I think they've got a decent chance, if they can land somewhere where folks can find them and let them out. You don't need food, water, toilets, etc. for just a few hours, and there should be enough air as well. Without power it probably gets cold, if anything, but that's OK for short while, and maybe they can grab some extra clothes on the way out. It would certainly be better to have seats, but if they lie down on the deck with their heads padded, the main shocks (parachute opening, water impact) might be survivable. Then someone has to find them and let them out. It's not fun, but in an emergency you take what you can get.
No they don't. There is no room for three to lay down. There is no heat, water or CO2 removal for the air. There is no way to let themselves out.
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Guys, all this was discussed before. The current Dragon cannot be used as a rescue craft. We have to wait for the manned version for that.
As for one of the Soyuzes becoming unusable, a spare one can, at a push, be sent unmanned to dock automatically with ISS. It means the crew of the incapacitated Soyuz will have to wait maybe a few extra months for their ride home.
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Are these things really NEEDED in an emergency? Suppose there are 6 astronauts on the station and a Soyuz catches fire and they need to evacuate. So three folks pile into the as-is Dragon, the remaining three close the hatch and cast it free, then take the remaining Soyuz home. Do the folks in the Dragon survive?
No they don't. There is no room for three to lay down. There is no heat, water or CO2 removal for the air. There is no way to let themselves out.
Addressing these issues in turn:
http://en.wikipedia.org/wiki/File:Inside_the_Dragon_(capsule).jpg
Looks like enough room for 2 folks to lie on their backs with their knees up; maybe 3 if the side part is flat.
Apollo 13 survived with no heat, and they don't need water since the air will run out first.
As far as air, both Houdini and Amazing Randi survived in underwater coffins for 1.5 hours. Houdini specified the size ( http://www.lettersofnote.com/2009/11/houdinis-last-trick.html ) of 0.57 cubic meter, actually less since his body took up some room. Straight extrapolation to 3 people, 10 cubic meters of Dragon gives 8.77 hours. These folks would be more excited, so say 5-6 hours.
So can they land somewhere, in water, where someone can get them out within this time? I guess yes. Each orbit must cross North or South America somewhere. This gives you two coasts to aim for. All these countries have navies with helicopters. With GPS and big parachutes it should be possible to find the capsule fairly easily, hopefully on the way down. It's OK to open the capsule destructively in this case, so tools should not be problem.
And no, this is not a realistic scenario, where there is an emergency important enough to leave but still time to unberth the Dragon. Just interesting to think what could be done in the spirit of Apollo 13 (though of course the Apollo 13 scenerio was thought through in advance).
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1. Looks like enough room for 2 folks to lie on their backs with their knees up; maybe 3 if the side part is flat.
2. Apollo 13 survived with no heat, and they don't need water since the air will run out first.
3 Straight extrapolation to 3 people, 10 cubic meters of Dragon gives 8.77 hours. These folks would be more excited, so say 5-6 hours.
4. So can they land somewhere, in water, where someone can get them out
5. within this time? I guess yes. Each orbit must cross North or South America somewhere. This gives you two coasts to aim for. All these countries have navies with helicopters. With GPS and big parachutes it should be possible to find the capsule fairly easily, hopefully on the way down. It's OK to open the capsule destructively in this case, so tools should not be problem.
None are valid
1. "Looks like" doesn't mean it is, which it isn't
2. The problem is the opposite, heat and water need to be removed from the air
3. 10 m3 is for an empty capsule without racks. Also, wrong subjects for extrapolation. There are two strikes, lack of fitness and excitation.
4. it is an emergency and picking a landing spot is not a given. Also, the high inclination of the orbit does put it out of the reach of coastal helicopters
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Okay, I've done report to mod three times on this thread already. Obviously the mods disagree with me, so I'll just whine instead.
I'm sorry I answered a newbie's question. I didn't think it would result in all this rehashing and speculative ISS disaster fiction.
Does anyone have anything Falcon or Dragon to talk about?
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Is the concept of "general discussion" unknown to you, or is whining always on-topic?
Fair enough.. guess I don't have to read every thread.
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Is the concept of "general discussion" unknown to you, or is whining always on-topic?
Fair enough.. guess I don't have to read every thread.
Sure you do because someone may add bit of info you didn't know before. For example I suggested un-berthing dragon required astros on the station. To which robotbeat replied it can be controlled from the ground. To which Jorge replied only preprogrammed ops can be done from the ground but not berthing/ un-birthing. I didn't know that and only found out by discussing something that pretty much everyone says isn't realistic :)
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1. Looks like enough room for 2 folks to lie on their backs with their knees up; maybe 3 if the side part is flat.
2. Apollo 13 survived with no heat, and they don't need water since the air will run out first.
3 Straight extrapolation to 3 people, 10 cubic meters of Dragon gives 8.77 hours. These folks would be more excited, so say 5-6 hours.
4. So can they land somewhere, in water, where someone can get them out
5. within this time? I guess yes. Each orbit must cross North or South America somewhere. This gives you two coasts to aim for. All these countries have navies with helicopters. With GPS and big parachutes it should be possible to find the capsule fairly easily, hopefully on the way down. It's OK to open the capsule destructively in this case, so tools should not be problem.
None are valid
1. "Looks like" doesn't mean it is, which it isn't
2. The problem is the opposite, heat and water need to be removed from the air
3. 10 m3 is for an empty capsule without racks. Also, wrong subjects for extrapolation. There are two strikes, lack of fitness and excitation.
4. it is an emergency and picking a landing spot is not a given. Also, the high inclination of the orbit does put it out of the reach of coastal helicopters
1. Quite possible, data is needed to settle this. What *are* the sizes? I looked and could not find them. Remember, the astronauts can remove the packages from the layer nearest the heat shield if that gives them more surface.
2. The cargo dragon is specified to supply 1500-2000 watts to the cargo; therefore they must be able to dissipate this without exceeding their max temp of 46 C. (See http://wsn.spaceflight.esa.int/docs/Factsheets/28%20SpaceXDragon%20LR.pdf for cargo power, http://www.spaceflight101.com/dragon-spacecraft-information.html for cabin temp) Three resting people will add about 300 watts. The temperature control should handle this easily.
3) Assuming 1000kg of stuff at an average density of 1, the stuff takes up only 1 m^3 of volume. That's 10% less air, but we left out an opposite factor of 10% since Houdini/Randi took up 10% of their coffins. Fitness and excitation are reasonable, but presumably astronauts are as rational as Houdini and Randi and will remain as still as possible. My proposal was that, all things considered, they were 50% more active than Houdini or Randi. What number do you think is reasonable?
4) North America extends past the northmost excursion of the ISS orbit, and South America below the southmost. Therefore every orbit must cross both the East and West coast of one of the Americas. There are no restrictions that I am aware of as to where you perform your de-orbit burns, so you can land as close as you want to either coast, subject only to not wanting to hit land. For North America the coastal cities, and Coast Guard bases, are close enough together you can surely get a helicopter there in time. South America is iffier, but it's an emergency and you take your chances (and many of orbits that cross South America then cross Western Europe, where the coast is dense with cities). You can also drop Seals or their equivalent, equipped with can-openers, from cargo planes if helicopters cannot reach or are too slow.
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4. So can they land somewhere, in water, where someone can get them out
4. it is an emergency and picking a landing spot is not a given. Also, the high inclination of the orbit does put it out of the reach of coastal helicopters
Ahem. Why are we talking helos. They aren't the fastest aircraft around.
One alternative is to drop para-frogmen out of a C130 or C17 transport first then emergency gear afterwards. The para-frogmen secure the capsule with flotation support gear and wait for the recovery ship.
Another alternative is to drop the para-frogmen from V-22 VTOL aircraft if the capsule lands near to a V-22 base or operations platform.
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A completely different topic.
Assuming that SpaceX can produce enough launch vehicles the launch sites become the limiting factor.
Vandenberg is not suitable for all trajectores. The large majority will launch at CCAFS How many flights a year out of CCAFS are realistic? I have not seen a discussion dedicated to this, just some general remarks. Apologies if I missed it.
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A completely different topic.
Assuming that SpaceX can produce enough launch vehicles the launch sites become the limiting factor.
Vandenberg is not suitable for all trajectores. The large majority will launch at CCAFS How many flights a year out of CCAFS are realistic? I have not seen a discussion dedicated to this, just some general remarks. Apologies if I missed it.
My guess is once a month - this is roughly the launch pace Ariane 4 has maintained in the 1990s. But that depends on how large the market share SpaceX has managed to catch.....
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I think one a month might be a bit optimistic with the current infrastructure.
At the moment the size of the hangar and its proximity to the pad means that they can only prepare one vehicle at a time. This could become a bottleneck if the flight rate goes up. As it stands, the launch campaign would have to be well under 30 days to achieve this kind of flight rate. I imagine that as they gain experience, the length of the campaign will come down.
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A completely different topic.
Assuming that SpaceX can produce enough launch vehicles the launch sites become the limiting factor.
Vandenberg is not suitable for all trajectores. The large majority will launch at CCAFS How many flights a year out of CCAFS are realistic? I have not seen a discussion dedicated to this, just some general remarks. Apologies if I missed it.
I would say any given pad at CCAFS will max out at 12 launches a year with an average interval of 4 weeks. This only becomes a problem if SpaceX has any missions that require a dual launch for any reason.
That said, I agree with Douglas about the bottleneck of the HIF and Hanger AO. At present, if you've got two sequential FH flights lined up, you're looking at a big delay.
Hmm...
Is the old Titan VAB up the crawlway from SLC-40 and -41 still there?
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From what I've been told the 1.1/FH cores are too long to fit in AO for processing. The 1.1 stages are supposed to come to us practically complete so should be less time to process than in the past. Besides, there may be other future plans for AO anyways.....
The Titan structures (SMAB/SMARF) are still there as well. Could be plans for one of those as well, nothing concrete yet... not 1st stage or core processing from what I've heard..
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1. Looks like enough room for 2 folks to lie on their backs with their knees up; maybe 3 if the side part is flat.
2. Apollo 13 survived with no heat, and they don't need water since the air will run out first.
3 Straight extrapolation to 3 people, 10 cubic meters of Dragon gives 8.77 hours. These folks would be more excited, so say 5-6 hours.
4. So can they land somewhere, in water, where someone can get them out
5. within this time? I guess yes. Each orbit must cross North or South America somewhere. This gives you two coasts to aim for. All these countries have navies with helicopters. With GPS and big parachutes it should be possible to find the capsule fairly easily, hopefully on the way down. It's OK to open the capsule destructively in this case, so tools should not be problem.
None are valid
1. "Looks like" doesn't mean it is, which it isn't
2. The problem is the opposite, heat and water need to be removed from the air
3. 10 m3 is for an empty capsule without racks. Also, wrong subjects for extrapolation. There are two strikes, lack of fitness and excitation.
4. it is an emergency and picking a landing spot is not a given. Also, the high inclination of the orbit does put it out of the reach of coastal helicopters
2. The cargo dragon is specified to supply 1500-2000 watts to the cargo; therefore they must be able to dissipate this without exceeding their max temp of 46 C. (See http://wsn.spaceflight.esa.int/docs/Factsheets/28%20SpaceXDragon%20LR.pdf for cargo power, http://www.spaceflight101.com/dragon-spacecraft-information.html for cabin temp) Three resting people will add about 300 watts. The temperature control should handle this easily.
There's a difference between dissipating heat loads from rack-mounted equipment connected to active thermal control loops and removing heat from the ambient air, which must be evenly and fully circulated throughout the entire volume of the pressurized cabin.
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Thanks for the replies. I could have imagined that there is no simple answer. Could someone please tell me what AO stands for?
Yes I was looking for dual launch missions beside total capacity. Exciting things could be done with two FH launches. But that would require two independent pads, I imagine.
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The Titan structures (SMAB/SMARF) are still there as well. Could be plans for one of those as well, nothing concrete yet... not 1st stage or core processing from what I've heard..
Sorry, I'm silly but I've just had a mental image of that building with all its high bay doors open with a row of FHs and F9s ready to be rolled out. :D
Could someone please tell me what AO stands for?
'AO' is just the building designation. As ugordan mentions below, it's previous role was a storage facility for Delta-IIs.
[edit]
Replied to guckyfan
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Could someone please tell me what AO stands for?
Hangar AO.
http://www.collectspace.com/ubb/Forum35/HTML/000493.html
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That is the larger group of women at SpaceX - They made a separate picture of just the women engineers - you can see that here:
https://twitter.com/SpaceX/status/304699525635907584/photo/1
That needs to appear here: http://shop.spacex.com/ as a poster. To inspire young women...
I'll stop there. Please do likewise.
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Is the old Titan VAB up the crawlway from SLC-40 and -41 still there?
It was torn down
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Popular science April edition has a "How it works" issue. The Front cover is the Falcon Heavy.
Link is here:http://www.popsci.com/science/article/2013-03/most-powerful-space-rocket (http://www.popsci.com/science/article/2013-03/most-powerful-space-rocket)
The surprise that I do not think I have heard before is that cross-feed is not used unless the payload is over 100,000 lbs.
PopSci Quote:
2) FIRST STAGE: THREE ROCKET CORES
Falcon Heavy’s first stage consists of three cores. All three cores operate together at liftoff. About T+2:45 minutes into flight, the center core throttles down while the two side cores continue at full thrust until their fuel is nearly spent. At that point, pneumatic separators release the side cores, which plummet into the ocean, and the center core throttles up.
3) CENTER CORE
For payloads heavier than 100,000 pounds, Falcon Heavy uses a cross-feed system to run fuel from the side cores to the center core, leaving the center core almost fully fueled after the side boosters separate. What’s left is the equivalent of a complete Falcon 9 rocket already high in space.
And then later it has the time line that shows center core throttling down 15 sec before side cores burn out and the center only burns for 30 seconds extra.
T + 0:02:45
The rocket has now burned enough fuel (thus decreasing its mass) that the center core engines can throttle down.
T + 0:03:00
The side cores separate and fall into the ocean, while the center core’s nine Merlin engines continue to burn for approximately 30 seconds.
T + 0:03:30
The second stage separates from the remaining first-stage core. The second-stage engine ignites and continues toward orbit.
Does this all make sense?
So, with all the complications added for the cross-feed is only for the benefit of an extra 17,000 lbs.
I was thinking one of the benefits of the cross-feed once re usability starts it to burn the side cores quickly so they are not a downrange and have a little reduced velocity to get the cores turned around and headed back to the launch pad. Maybe the FHR will change all the above.
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I wouldn't take whatever they wrote with a grain of salt. The higher energy orbits would benefit more from cross feeding than the lower orbits. But to give you an idea, according to ULA, using cross feeding would give 5 extra tonnes. Which was about an extra 20%. Of course the Delta IV doesn't have such a good T/W so the gravity losses are greater.
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Popular science April edition has a "How it works" issue. The Front cover is the Falcon Heavy.
Link is here:http://www.popsci.com/science/article/2013-03/most-powerful-space-rocket (http://www.popsci.com/science/article/2013-03/most-powerful-space-rocket)
PopSci Quote:
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Does this all make sense?
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Yes. Obviously they give timeline for the case with NO cross-feed -- otherwise it would take center core about 3 min. to burn the full tanks dry.
So, with all the complications added for the cross-feed is only for the benefit of an extra 17,000 lbs.
It's not "only" 17,000 lbs, it's bold 17%. Pretty close to the number baldusi quoted.
The surprise that I do not think I have heard before is that cross-feed is not used unless the payload is over 100,000 lbs.
Think of cross-feed as of SRBs on Atlas or Delta: you won't use SRB if there is no need, they cost money.
And thanks for the link, I've seen the pictures, but not the time line.
By this time line, they use 91.6% fuel in side boosters. Looks like these 8.4% are for powered reentry
:)
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The surprise that I do not think I have heard before is that cross-feed is not used unless the payload is over 100,000 lbs.
Think of cross-feed as of SRBs on Atlas or Delta: you won't use SRB if there is no need, they cost money.
But it costs more to fly different configurations. FH will already have different core from the boosters (different length and crossfeed flow direction), and if you fly non-crossfeed, you'll need another version of both. More configurations cost more $, and complicates matters. It also takes longer to become confident in crossfeed if you fly without it most of the time.
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The surprise that I do not think I have heard before is that cross-feed is not used unless the payload is over 100,000 lbs.
Think of cross-feed as of SRBs on Atlas or Delta: you won't use SRB if there is no need, they cost money.
But it costs more to fly different configurations. FH will already have different core from the boosters (different length and crossfeed flow direction), and if you fly non-crossfeed, you'll need another version of both. More configurations cost more $, and complicates matters. It also takes longer to become confident in crossfeed if you fly without it most of the time.
It costs more to build different configurations. It costs less to build a cross feed capable configuration, and then save money by not installing the subcomponents that are required for cross feed (i.e. actuators for cross feed piping) on flights that do not need it.
Flying cross feed full time would mean that stage separation and the rest of the mission critical events for the light payloads end up being significantly further out, higher altitude, and higher velocity than for heavier payloads. It may be that the costs to potential first stage re-usability and or avionics development to cover such an expanded envelope of flight for the various flight events is not insignificant.
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But it costs more to fly different configurations. FH will already have different core from the boosters (different length and crossfeed flow direction), and if you fly non-crossfeed, you'll need another version of both.
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No, this is not how I see this.
Cross-feeding means that during the flight you pump propellants from side tanks into the core with THE SAME rate as NINE M1Ds consume. That's A LOT of pumping, and a lot of energy to keep pumps running. The cost of this system is much more than 4 pairs of fittings on the tanks.
Once again, the example with strapons on Atlas V is valid to some extent: the support system and locks/jettisons add some cost, but the cost of SRBs is much higher.
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But it costs more to fly different configurations. FH will already have different core from the boosters (different length and crossfeed flow direction), and if you fly non-crossfeed, you'll need another version of both.
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No, this is not how I see this.
Cross-feeding means that during the flight you pump propellants from side tanks into the core with THE SAME rate as NINE M1Ds consume. That's A LOT of pumping, and a lot of energy to keep pumps running. The cost of this system is much more than 4 pairs of fittings on the tanks.
Once again, the example with strapons on Atlas V is valid to some extent: the support system and locks/jettisons add some cost, but the cost of SRBs is much higher.
There's no pump whatsoever in the plumbing of any rocket. Some engines might implement a low pressure turbine to avoid cavitation problems. But tank pressurization (50psi in the Falcon 9 case), gravity and acceleration couple with wide pipes feed the engines. Cross feeding implementations, like the Atlas II, Falcon Heavy or the Angara 5 use simple piping couples to the manifolds. The big design issue is the quick disconnect and the extra tank penetrations. I repeat, there's no pumping (unless you consider the tank pressurization a pump of sorts).
I don't really understand your Atlas V comment.
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I find it strange. No X-Feed also means the side cores separate later in the flight, and for a company that wants to bring them back I'd think they want the side cores to drop away as soon as possible.
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I find it strange. No X-Feed also means the side cores separate later in the flight, and for a company that wants to bring them back I'd think they want the side cores to drop away as soon as possible.
It's a matter of insurance and risk. Once they have actually developed a boost back booster, they might chance that. But as long as they use it as an expendable rocket, the XF adds risk and thus increases insurance cost. Thus, I doubt any client will use it unless there's a very good reason for it.
As I stated before, I suspect the XF effect will be more marked for high energy orbits.
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You're assuming "will not be used" means "will not be installed on the rocket", correct?
Having configuration changes increases risk. I'd think they will install the same piping every time, and once installed, I see no reason not to use them. (The usage itself does not add risk - it adds performance margin, which reduces risk)
In short, I am not sure I trust the PM article to have gotten everything right.
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You're assuming "will not be used" means "will not be installed on the rocket", correct?
Having configuration changes increases risk. I'd think they will install the same piping every time, and once installed, I see no reason not to use them. (The usage itself does not add risk - it adds performance margin, which reduces risk)
There's always risk of a bad seal. But the real risk is a failure at separation. Either a QD that doesn't disconnects or that doesn't seals once separated. Thus, you don't install the QD, just plug the pipes and don't use X F.
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There's no pump whatsoever in the plumbing of any rocket. Some engines might implement a low pressure turbine to avoid cavitation problems. But tank pressurization (50psi in the Falcon 9 case), gravity and acceleration couple with wide pipes feed the engines. Cross feeding implementations, like the Atlas II, Falcon Heavy or the Angara 5 use simple piping couples to the manifolds. The big design issue is the quick disconnect and the extra tank penetrations. I repeat, there's no pumping (unless you consider the tank pressurization a pump of sorts).
I don't really understand your Atlas V comment.
>>There's no pump whatsoever in the plumbing of any rocket.
I'm sorry, may be it's my fault, in Russian for "pump" and "turbopump" we can use same word.
So, I mean turbopump, like the one which feeds propellants into the engine. As I understand, it is necessary to create working pressure in combustion chamber and supply propellants at working rate.
In my understanding (and I'm not an expert here) cross-feed in case of FH requires pumping:
First, side buster has roughly 330 mT of propellants, and in just 2 minutes it burns 220 and _transfers_ the rest - 110 mT - to the core. Which gives combined cross-feed flow rate of 0.9 mT per second.
Again, I'm no expert, I have general engineering background - and I really can't imagine that kind of flow WITHOUT any external pumping.
Second, the tanks are at same level, so at the end you will have to push the liquid UP some 10-15 meters to top nearly-full core from nearly-empty sides. Ok, lets say it is 15 meters, LOX with 1.1 g/ml and at acceleration of 5 g. This gives the pressure difference of 15*1.1*5 atm = 82 atm. This is the excess pressure in side buster tank which is required just to keep LOX from going backwards, from the core.
Once again, I can't see how "simple piping couples to the manifolds" could work here.
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Atlas II -- Do you have any link with it cross-feed system described? That would be nice
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There's no pump whatsoever in the plumbing of any rocket. Some engines might implement a low pressure turbine to avoid cavitation problems. But tank pressurization (50psi in the Falcon 9 case), gravity and acceleration couple with wide pipes feed the engines. Cross feeding implementations, like the Atlas II, Falcon Heavy or the Angara 5 use simple piping couples to the manifolds. The big design issue is the quick disconnect and the extra tank penetrations. I repeat, there's no pumping (unless you consider the tank pressurization a pump of sorts).
I don't really understand your Atlas V comment.
>>There's no pump whatsoever in the plumbing of any rocket.
I'm sorry, may be it's my fault, in Russian for "pump" and "turbopump" we can use same word.
So, I mean turbopump, like the one which feeds propellants into the engine. As I understand, it is necessary to create working pressure in combustion chamber and supply propellants at working rate.
In my understanding (and I'm not an expert here) cross-feed in case of FH requires pumping:
First, side buster has roughly 330 mT of propellants, and in just 2 minutes it burns 220 and _transfers_ the rest - 110 mT - to the core. Which gives combined cross-feed flow rate of 0.9 mT per second.
Again, I'm no expert, I have general engineering background - and I really can't imagine that kind of flow WITHOUT any external pumping.
Second, the tanks are at same level, so at the end you will have to push the liquid UP some 10-15 meters to top nearly-full core from nearly-empty sides. Ok, lets say it is 15 meters, LOX with 1.1 g/ml and at acceleration of 5 g. This gives the pressure difference of 15*1.1*5 atm = 82 atm. This is the excess pressure in side buster tank which is required just to keep LOX from going backwards, from the core.
Once again, I can't see how "simple piping couples to the manifolds" could work here.
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Atlas II -- Do you have any link with it cross-feed system described? That would be nice
It was speculated that FH crossfeed works without pumping against hydrostatic forces. It works in the following way: center 3 engines of center core always operate from center tank. They could be throttled back in the first phase of flight to save fuel.
But the outer 6 engines of center core operate from side boosters in the first phase of flight. Just before the fuel in side boosters runs out, those outer engines of center core are switched to operate from center core.
Arguably, this could be accomplished without sudden pressure surge by using appropriate kind of valve, switching lines gradually.
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I find it strange. No X-Feed also means the side cores separate later in the flight, and for a company that wants to bring them back I'd think they want the side cores to drop away as soon as possible.
What if they want to recover the central core too? :-)
Cheers, Martin
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There's no pump whatsoever in the plumbing of any rocket. Some engines might implement a low pressure turbine to avoid cavitation problems. But tank pressurization (50psi in the Falcon 9 case), gravity and acceleration couple with wide pipes feed the engines. Cross feeding implementations, like the Atlas II, Falcon Heavy or the Angara 5 use simple piping couples to the manifolds. The big design issue is the quick disconnect and the extra tank penetrations. I repeat, there's no pumping (unless you consider the tank pressurization a pump of sorts).
I don't really understand your Atlas V comment.
>>There's no pump whatsoever in the plumbing of any rocket.
I'm sorry, may be it's my fault, in Russian for "pump" and "turbopump" we can use same word.
So, I mean turbopump, like the one which feeds propellants into the engine. As I understand, it is necessary to create working pressure in combustion chamber and supply propellants at working rate.
In my understanding (and I'm not an expert here) cross-feed in case of FH requires pumping:
First, side buster has roughly 330 mT of propellants, and in just 2 minutes it burns 220 and _transfers_ the rest - 110 mT - to the core. Which gives combined cross-feed flow rate of 0.9 mT per second.
Again, I'm no expert, I have general engineering background - and I really can't imagine that kind of flow WITHOUT any external pumping.
Second, the tanks are at same level, so at the end you will have to push the liquid UP some 10-15 meters to top nearly-full core from nearly-empty sides. Ok, lets say it is 15 meters, LOX with 1.1 g/ml and at acceleration of 5 g. This gives the pressure difference of 15*1.1*5 atm = 82 atm. This is the excess pressure in side buster tank which is required just to keep LOX from going backwards, from the core.
Once again, I can't see how "simple piping couples to the manifolds" could work here.
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Atlas II -- Do you have any link with it cross-feed system described? That would be nice
The only pumps whatsoever are in the engines (turbopump, hydraulic pumps, etc). Some rockets might use a small pump to keep pressurizing the tanks, but normally they either use a dedicated pressurant tank with a regulator (like He or N), reheat some propellant through a radiator in the engine or take a bit of the output of the gas generator.
All the pumping is done but the engine's turbopumps. As long as you can keep a positive pressure on the engine's incoming line, you up the pressure with the turbopump.
In the case of the pressure fed designs, you don't even use a pump. You just regulate the pressure on the tank and use only that to feed the combustion chamber.
In the case of some small thrusters, you might have some diaphragm between the pessurant gas and the propellant, so you could say that the tank and pressurization system is a diaphragm pump.
But once you have a positive pressure on the inline pipe of the engine, you simple use a wider pipe, and let the pump up the pressure. Please remember the propellant are almost uncompressible, and as long as you keep moving the same volume without cavitation, it doesn't matter the pressure.
Regarding the need to pump "up" the propellant, you are picturing it wrong. Go look to this post (http://forum.nasaspaceflight.com/index.php?topic=28424.msg877014#msg877014), that shows the Angara cross feed arrangement. You'll see that the couple is done at the bottom of the tank. Thus, you only need a little extra pressure on the boosters than the center engine. Or a valve on the main tank that when open displaces the flux from the boosters.
Also, Elon stated that the Falcon Heavy cross feeding worked byt feeding the outer engines of one side from the booster of that side. This means two things. First, that they'll keep the center engine fed from the central tank. And second, that they can make the connection directly at the manifold (look at the top image, that's where all the engines feed from the tank) (http://forum.nasaspaceflight.com/index.php?topic=29130.msg963291#msg963291).
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It was speculated that FH crossfeed works without pumping against hydrostatic forces. It works in the following way: center 3 engines of center core always operate from center tank. They could be throttled back in the first phase of flight to save fuel.
But the outer 6 engines of center core operate from side boosters in the first phase of flight. Just before the fuel in side boosters runs out, those outer engines of center core are switched to operate from center core.
Arguably, this could be accomplished without sudden pressure surge by using appropriate kind of valve, switching lines gradually.
Thanks a lot! This clarifies the whole thing.
In this case, it is just pipes, valves and manifolds, indeed.
>>switching lines gradually
"Gradually" means - one engine at a time?
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I find it strange. No X-Feed also means the side cores separate later in the flight, and for a company that wants to bring them back I'd think they want the side cores to drop away as soon as possible.
What if they want to recover the central core too? :-)
Maybe partly accounts for the published $45M price differential ($83M vs. $128M) for > 6.4t to GTO? Always wondered if that might be an indication of cross-feed costs, non-recoverability premium, market pricing, ...?
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@baldusi
Thank you for so detailed explanation, it helps a lot!
And thanks for the link to the cross-feed thread, I did not see it.
I'll read it through.
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I find it strange. No X-Feed also means the side cores separate later in the flight, and for a company that wants to bring them back I'd think they want the side cores to drop away as soon as possible.
What if they want to recover the central core too? :-)
Cheers, Martin
They do, but this stays the same.... (except for the extra performance of course). But since fly-back costs fuel, keeping the side cores attached for longer means that you'll need to reserve more propellant...
So while in an EELV, X-feed means simply that you carry the cores for less time and have a fully fueled center core at separation, with an RLV it bites you one more time on the way back.
The valving is interesting. The pressure at the pump inlet is proportional to the liquid column height and to the acceleration. When switching from the empty side core to the center core, pressure will increase. Also, until you close the path to the side core, fuel will try to flow back to it, to equalize the heights.
The solution I would try would be a 5-second pressurized buffer tank. So I can shut the side core first, and then within 5 seconds open the center core path.
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ELV. Delta IV and Atlas V are the only EELV's. EELV's was a specific contract for the DOD.
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[quote author=MP99 link=topic=30385.msg1026742#msg1026742
The valving is interesting. The pressure at the pump inlet is proportional to the liquid column height and to the acceleration. When switching from the empty side core to the center core, pressure will increase. Also, until you close the path to the side core, fuel will try to flow back to it, to equalize the heights.
Just add gas to side boosters to keep them above the core pressure,
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[quote author=MP99 link=topic=30385.msg1026742#msg1026742
The valving is interesting. The pressure at the pump inlet is proportional to the liquid column height and to the acceleration. When switching from the empty side core to the center core, pressure will increase. Also, until you close the path to the side core, fuel will try to flow back to it, to equalize the heights.
Just add gas to side boosters to keep them above the core pressure,
A few issues:
1. It solves the back flow, but still requires instantaneous valving action.
2. That's a hell of a lot of has pressure and a hell of a lot of volume.
3. It applies high pressure to the top of the tank, whereas before the high pressure was only at the bottom of the tank. I don't know if the structure is optimized around this gradient.
4. The buffer tank is also very useful for zero-g restarts.
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[quote author=MP99 link=topic=30385.msg1026742#msg1026742
The valving is interesting. The pressure at the pump inlet is proportional to the liquid column height and to the acceleration. When switching from the empty side core to the center core, pressure will increase. Also, until you close the path to the side core, fuel will try to flow back to it, to equalize the heights.
Just add gas to side boosters to keep them above the core pressure,
A few issues:
1. It solves the back flow, but still requires instantaneous valving action.
2. That's a hell of a lot of has pressure and a hell of a lot of volume.
3. It applies high pressure to the top of the tank, whereas before the high pressure was only at the bottom of the tank. I don't know if the structure is optimized around this gradient.
4. The buffer tank is also very useful for zero-g restarts.
Look at the "ball valve" :) I have drawn, you can rotate it slowly (1 second or even more) so there is no sudden pressure surge on turbopump inlet.
When you rotate it there is the period when the tanks are connected, so some liquid will flow into side boosters, that is no problem, you just switch off boosters 0.1 seconds later.
Do not look for solution (buffer tank???) if there is no problem! :)
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Look at the "ball valve"
3-way valve may work in the central core but you need cutoff valves in the side boosters too. Otherwise they would blow all residuals upon the central core when separated.
Wouldn't the TPs require stable NPSH (http://en.wikipedia.org/wiki/NPSH) anyway, so different ullage pressures in side boosters and central core near separation event is given.
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ELV. Delta IV and Atlas V are the only EELV's. EELV's was a specific contract for the DOD.
Isn't that changing? IIRC, the Air Force is in the process of certifying F9 and F9H as EELVs under NEEP. Hmm... link:
http://www.spacex.com/press.php?page=20121205 (http://www.spacex.com/press.php?page=20121205)
These two missions will support the EELV certification process for both the Falcon 9 and Falcon Heavy. Falcon Heavy, the most powerful rocket in the world, is expected to take its first flight in the second half of 2013. Building on reliable flight proven architecture, the Falcon 9 and Falcon Heavy launch vehicles are designed for exceptional reliability, meeting the stringent U.S. Air Force requirements for the Evolved Expendable Launch Vehicle (EELV) program.
-R C
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No. Air Force is not certifying F9 and F9H as EELV's, they are certifying that they meet the requirements of the EELV program.
The first "E" in EELV means Evolved. Falcon 9 did not evolved from previous ELV's unlike Delta IV and Atlas V and was not developed under the EELV contract. Falcon 9 is a EELV class vehicle but it is not an EELV.
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[quote author=MP99 link=topic=30385.msg1026742#msg1026742
The valving is interesting. The pressure at the pump inlet is proportional to the liquid column height and to the acceleration. When switching from the empty side core to the center core, pressure will increase. Also, until you close the path to the side core, fuel will try to flow back to it, to equalize the heights.
Just add gas to side boosters to keep them above the core pressure,
A few issues:
1. It solves the back flow, but still requires instantaneous valving action.
2. That's a hell of a lot of has pressure and a hell of a lot of volume.
3. It applies high pressure to the top of the tank, whereas before the high pressure was only at the bottom of the tank. I don't know if the structure is optimized around this gradient.
4. The buffer tank is also very useful for zero-g restarts.
Look at the "ball valve" :) I have drawn, you can rotate it slowly (1 second or even more) so there is no sudden pressure surge on turbopump inlet.
When you rotate it there is the period when the tanks are connected, so some liquid will flow into side boosters, that is no problem, you just switch off boosters 0.1 seconds later.
Do not look for solution (buffer tank???) if there is no problem! :)
A ball valve is not needed. Think simpler! If you have two tanks feeding a burner, one your adding pressure (side boosters) and the other your not (center core) then the flow will come from the side tanks and not the center tank. When you need to switch to core flow you start to pressurize the center tank which will decrease flow from the sides to zero. Now you close the QDs to the boosters without interrupting flow to the core engines.
The connections just have to be sized to flow the volume needed from each side booster. No propellant from the side booster needs to travel up into the center tank.
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There was a thread on all this earlier.
http://forum.nasaspaceflight.com/index.php?topic=28424.0
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The first "E" in EELV means Evolved. Falcon 9 did not evolved from previous ELV's unlike Delta IV and Atlas V and was not developed under the EELV contract. Falcon 9 is a EELV class vehicle but it is not an EELV.
Hmmmm. That sounds like a distinction without a difference.
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Ok, lets say it is 15 meters, LOX with 1.1 g/ml and at acceleration of 5 g. This gives the pressure difference of 15*1.1*5 atm = 82 atm. This is the excess pressure in side buster tank which is required just to keep LOX from going backwards, from the core.
Wrong calculation. You forgot to multiply by 9.8 (g), multiply by 1000 (density is kg/m) and divide by 101000 (KiloPascals in atm).
Not 82, but around 8 atm.
82 atm (1200 psi) looks more like the pressure in the combustion chamber! :)
A ball valve is not needed. Think simpler! If you have two tanks feeding a burner, one your adding pressure (side boosters) and the other your not (center core) then the flow will come from the side tanks and not the center tank. When you need to switch to core flow you start to pressurize the center tank which will decrease flow from the sides to zero. Now you close the QDs to the boosters without interrupting flow to the core engines.
You will need a cut-off valves anyway. I do not know if it is easy to balance delicate pressure difference between tanks. Without 3-way valve the side boosters become also interconnected and can exchange fluid between them, so may be 3-way valve is simple enough to simplify control logic. We may learn what approach SpaceX selected closer to actual launch.
I'm sure Elon will take this opportunity to boast how unheavenly smart his team is!
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The first "E" in EELV means Evolved. Falcon 9 did not evolved from previous ELV's unlike Delta IV and Atlas V and was not developed under the EELV contract. Falcon 9 is a EELV class vehicle but it is not an EELV.
Hmmmm. That sounds like a distinction without a difference.
Far from it. Thumb is a finger but not all fingers are thumbs
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You're not defining the rocket. You're defining the word. There might be a lot less difference between F9 1.0 and 1.1 than there is between the Atlas V and the previous model, but "evolved" is still a perfectly valid term. Maybe a better term for the F9, seeing how the Delta and Atlas are closer to entirely new rockets.
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You're not defining the rocket. You're defining the word. There might be a lot less difference between F9 1.0 and 1.1 than there is between the Atlas V and the previous model, but "evolved" is still a perfectly valid term. Maybe a better term for the F9, seeing how the Delta and Atlas are closer to entirely new rockets.
It doesn't matter about the difference between F9 1.0 and 1.1. F9 was not a contender for the intital EELV contracts and therefore is not an EELV, it is just a plain ELV. EELV is specific title for some specific contracts. No other vehicles were procured under those contracts and therefore the term is not applicable as a proper name to other vehicles.
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This was wandering all over the place again, with some really crap "LOLZ!" level posts - from members who really should know better. Trimmed, but you can see it's still shaky, so started a new thread.
http://forum.nasaspaceflight.com/index.php?topic=31402.0