Author Topic: SpaceX Falcon 9 / Dragon 2 : SpX-DM1 : March 2, 2019 : DISCUSSION (Read 601824 times)

ZChris13 · « **Reply #720 on:** 02/28/2019 10:04 pm »

Quote from: High Bay 4 on 02/28/2019 05:58 pm

During the CRS-16 pre-launch briefing Hans mentioned using Firing Room 4 at the LC-39 LCC for future launches. Anyone know if it will be used for this Saturday's DM-1 launch?

that was confirmed in the briefing on NASA TV a few hours ago, they are in Firing Room 4.

Almurray1958 · « **Reply #721 on:** 02/28/2019 10:23 pm »

Three questions:
Launch time in the oh-so-dark. I assume that's orbital dynamics with the ISS' orbit? It seems like in the 1960s they tried to do daylight launches to get the best views.

--yes, launch time is dictated by orbital mechanics. When the orbital plane comes closest to te launch site si when they'll launch.

In the eastern USA is there a chance to see powered flight (8 minutes 57 seconds up along the east coast, like the STS) or is the 'flat' trajectory keeping it below our horizon?

probably not, the launch vector is pretty much eastward and won't be visible this far north

We have a low in the northwest overflight of the ISS a few hours before docking. Heavens-above.com predicts magnitude -1.9, not as bright as typically. Is that too low and too dim to see Dragon?
https://heavens-above.com/passdetails.aspx?lat=41.034&lng=-73.7629&loc=White+Plains&alt=65&tz=EST&sa...

- the pass is very low in the NW, no higher than 19° from 42 north. If you have a good northern horizon and clear skies and dark skies, then maybe. But your tag mentions NYC, so...

Thank you - pointing to where I may have missed the answer to the first question would be fine.
If you have a link I missed to visibility of Dragon's powered flight, let me know.
Of course, the weather not looking favorable in the northeast USA this weekend.
bob

ejb749 · « **Reply #722 on:** 02/28/2019 10:25 pm »

This should be a routine launch, so darkness shouldn't be an issue. The fun stuff doesn't start until rendezvous.

Anyone know if the mannequin is already loaded, or will they be using the access arm?

Jeff Lerner · « **Reply #723 on:** 03/01/2019 01:30 am »

There is a lot riding on this DM1 flight...lots of new spacecraft parts and functionality...

I’m curious as to what is the minimum to be considered mission success for this Dragon ?

What has to work 100% ??..what could fail or partially fail, and not require a re-flight before NASA would allow a manned Dragon ??

Steven Pietrobon · « **Reply #724 on:** 03/01/2019 04:17 am »

Quote from: Jeff Lerner on 03/01/2019 01:30 am

I’m curious as to what is the minimum to be considered mission success for this Dragon ?

That it comes back in one piece and doesn't crash into ISS. An unsuccessful rendezvous and docking would probably mean crew would fly next anyway, as they can do a manual docking if the automatic systems still has bugs.

punder · « **Reply #725 on:** 03/01/2019 04:17 am »

Just some silly random musings here...

Iain M. Banks is my favorite science fiction author. Well, maybe after RAH. And Ripley is my favorite sci-fi movie hero. SpaceX punches all my buttons anyway, but it's gratifying that they also seem to share my own personal space craziness... or should I say, I share theirs.

Watching the last couple of press conferences, obviously Kathy and Hans have developed a personal bond. Technology is great. But it's people who make technology happen, who use technology to achieve their goals--really, to realize their dreams--and, I'm not ashamed to say, it warmed my heart to watch these people joking and poking each other and smiling in the midst of this deadly serious endeavor. Good luck to them, and to all of us.

docmordrid · « **Reply #726 on:** 03/01/2019 06:17 am »

Elon Musk ✔ @elonmusk
Ripley
1:37 AM - Mar 1, 2019

https://twitter.com/elonmusk/status/1101370880486076416

Norm38 · « **Reply #727 on:** 03/01/2019 02:02 pm »

Quote from: Chris Bergin on 03/01/2019 01:34 pm

Some confusion on the Russian stance per Dragon 2's DM-1 docking. On ISS Space to Ground - they are still NO GO for Dragon 2 DM-1 docking.

Recording of the conversation by https://twitter.com/Sunny_820

Conversation was 1 pm UTC today.

"What the heck!" is right. The Russians want the station crew huddled by the Soyuz, braced for impact?
All 16 Dragon missions have seen the ship come very gently, very slowly, very controlled up to the station. And they're acting like some completely untested thing is going to plow into them.

How much authority does Russia have to deny docking? Can the US deny a Progress/Soyuz docking?

MattMason · « **Reply #728 on:** 03/01/2019 02:22 pm »

Quote from: Norm38 on 03/01/2019 02:02 pm

Quote from: Chris Bergin on 03/01/2019 01:34 pm
Some confusion on the Russian stance per Dragon 2's DM-1 docking. On ISS Space to Ground - they are still NO GO for Dragon 2 DM-1 docking.

Recording of the conversation by https://twitter.com/Sunny_820

Conversation was 1 pm UTC today.

"What the heck!" is right. The Russians want the station crew huddled by the Soyuz, braced for impact?
All 16 Dragon missions have seen the ship come very gently, very slowly, very controlled up to the station. And they're acting like some completely untested thing is going to plow into them.

How much authority does Russia have to deny docking? Can the US deny a Progress/Soyuz docking?

I appreciate their concern, especially since their nearly exclusive use of autonomous docking for everything they have (including station modules) have resulted in two or three collisions.

That said, the US autonomous system isn't a third-party system as KURS is. In my opinion, the US has far greater technical sophistication in spacecraft systems in general. Proof? How many successful Mars landings or orbiters has Russian/Soviet technology made over the years?

And, lately, the US is really overdoing their risk management reviews to ensure that such a collision event is virtually unlikely.

A Crew Dragon is certainly using the same tech used by a small Dragon spacecraft (that arrives pretty darned close to the ISS) before being berthed.

gongora · « **Reply #729 on:** 03/01/2019 02:34 pm »

This is a mission thread. Please keep the discussion on DM-1, not what you think of the Russian space program.

abaddon · « **Reply #730 on:** 03/01/2019 02:41 pm »

Quote from: edkyle99 on 02/27/2019 01:49 pm

From the press briefing (below). I hope Stephen got his answer (drives me crazy that they don't share the numbers with the public). The "Internet" suggests Crew Dragon may weigh 11-ish tonnes fueled without cargo, and up to 14+ tonnes with cargo. Whatever the DM1 number, I expect this to be the heaviest-ever Falcon 9 payload.

"Stephen Clark, Spaceflight Now: Hi, Stephen Clark, Spaceflight Now, again. One question for maybe Hans or Kathy. Do you know about what the weight of the spacecraft is, in terms of pounds or kilograms at launch with all the fuel and cargo or crew loaded. About how heavy is it? And a little way ahead for the next week, you mentioned testing and analysis, what sort of milestones do you have over the next seven days to get ready for the launch? Fueling of the spacecraft with hypergolic fuel, et cetera.

Kathy Lueders, CCP: Well, the spacecraft, I'll have Stephanie get the specifics, she can get the specific weight, but the spacecraft's fueled right now. It's fueled, it's ready to go. It's over. And our folks have been following along with the fueling operation. We're moving towards obviously getting ready for Launch Readiness Review, which I think right now is the 27th. And we're rolling out to the pad on the 28th."

- Ed Kyle

So, as linked in the update thread, we have our answer: Crew Dragon and cargo mass 26577 pounds (isn't that a very precise number) or 12055 kilograms / 12 metric tons. The cargo is 449.7 pounds (but does this include Ripley? Probably not). So we're looking at ~11.75 fueled for DM-1 Crew Dragon, sans cargo.

daedalus1 · « **Reply #731 on:** 03/01/2019 02:43 pm »

Quote from: gongora on 03/01/2019 02:34 pm

This is a mission thread. Please keep the discussion on DM-1, not what you think of the Russian space program.

The Russians queried the safety of the Dragon, so they made themselves part of this thread.

abaddon · « **Reply #732 on:** 03/01/2019 02:48 pm »

Quote from: daedalus1 on 03/01/2019 02:43 pm

Quote from: gongora on 03/01/2019 02:34 pm
This is a mission thread. Please keep the discussion on DM-1, not what you think of the Russian space program.

The Russians queried the safety of the Dragon, so they made themselves part of this thread.

I would suggest discussion of the lack of Russian approval for docking is on topic, general aspersions of the Russian space program are not...

butters · « **Reply #733 on:** 03/01/2019 03:24 pm »

If I'm interpreting the ISS radio translation correctly, the Russians are concerned about a phase of the approach between 45 and 30 meters where Dragon is supposed to increase its approach rate from 0.3 to 0.8 m/s, and the Russians are concerned at what might happen if Dragon fails to accelerate and continues toward the station at a slower speed than is typically used for Soyuz/Progress dockings. Is that correct?

I also found it interesting that the Russians seemed to feel as if all the information has been dumped on them at the last minute. This program is no spring chicken, SpaceX and NASA have been fighting the battle of paperwork mountain for years, and on the eve of launch, the Russians are surprised by approach rates? It's almost hard to believe, but then again, the flow of information on this program has been tightly controlled and relatively inscrutable from the outside.

MattMason · « **Reply #734 on:** 03/01/2019 03:35 pm »

Quote from: gongora on 03/01/2019 02:34 pm

This is a mission thread. Please keep the discussion on DM-1, not what you think of the Russian space program.

Understood and apologies for any toe-stepping. Not attempting to start a bait on that but only to contrast a relevant fact, especially in light of past CRS and other automated visiting vehicles, Russian or otherwise.

BeamRider · « **Reply #735 on:** 03/01/2019 03:43 pm »

Scanned back several pages and do not see a prediction of times of approach and docking with ISS, to check on pass visibility. What is a good source for that info?

Ps. Saw two successive passes while a Cygnus module was approaching ISS, and the angular sep was reduced from ~10 deg on first pass to “double star” proximity on second. Very cool experience!

envy887 · « **Reply #736 on:** 03/01/2019 03:48 pm »

Quote from: abaddon on 03/01/2019 02:41 pm

Quote from: edkyle99 on 02/27/2019 01:49 pm
From the press briefing (below). I hope Stephen got his answer (drives me crazy that they don't share the numbers with the public). The "Internet" suggests Crew Dragon may weigh 11-ish tonnes fueled without cargo, and up to 14+ tonnes with cargo. Whatever the DM1 number, I expect this to be the heaviest-ever Falcon 9 payload.

"Stephen Clark, Spaceflight Now: Hi, Stephen Clark, Spaceflight Now, again. One question for maybe Hans or Kathy. Do you know about what the weight of the spacecraft is, in terms of pounds or kilograms at launch with all the fuel and cargo or crew loaded. About how heavy is it? And a little way ahead for the next week, you mentioned testing and analysis, what sort of milestones do you have over the next seven days to get ready for the launch? Fueling of the spacecraft with hypergolic fuel, et cetera.

Kathy Lueders, CCP: Well, the spacecraft, I'll have Stephanie get the specifics, she can get the specific weight, but the spacecraft's fueled right now. It's fueled, it's ready to go. It's over. And our folks have been following along with the fueling operation. We're moving towards obviously getting ready for Launch Readiness Review, which I think right now is the 27th. And we're rolling out to the pad on the 28th."

- Ed Kyle
So, as linked in the update thread, we have our answer: Crew Dragon and cargo mass 26577 pounds (isn't that a very precise number) or 12055 kilograms / 12 metric tons. The cargo is 449.7 pounds (but does this include Ripley? Probably not). So we're looking at ~11.75 fueled for DM-1 Crew Dragon, sans cargo.

Per Stephen Clark's updates, that is the docking mass, not the launch mass. Dragon 2 doesn't shed any fairings between launch and docking, so except for some expended Draco RCS fuel I'm not sure what the difference would be.

Rocket Science · « **Reply #737 on:** 03/01/2019 04:10 pm »

We're supposed to believe that NASA approved Dragon for a Kamikaze run at the ISS... Give me a break and you know better...

AU1.52 · « **Reply #738 on:** 03/01/2019 04:20 pm »

Quote from: envy887 on 02/28/2019 12:05 pm

Quote from: FutureSpaceTourist on 02/27/2019 08:28 pm
...
Quote
LAUNCH, LANDING AND DRAGON DEPLOYMENT
(all times are approximate)
Hour/Min/Sec   Events
+00:00:58   Max Q (moment of peak mechanical stress on the rocket)
+00:02:33   1st stage main engine cutoff (MECO)
+00:02:38   1st and 2nd stages separate
+00:02:44   2nd stage engine starts
+00:07:48   1st stage entry burn
+00:08:57   2nd stage engine cutoff (SECO-1)
+00:09:26   1st stage entry burn
+00:09:37   1st stage landing
+00:10:59   Crew Dragon separates from 2nd stage
+00:12:00   Dragon nosecone open sequence begins

Why are there 2 first stage entry burns? From the listed times, the 2nd one should be the landing burn, although 11 seconds is a short landing burn. Usually those are 30 sec for a single engine landing.

Also do we know why they are opening the nose cone so early? Would not keeping it closed be an extra protection from MMOD possible damage to the dock? Are they opening it early to check they can open it?

kevinof · « **Reply #739 on:** 03/01/2019 04:24 pm »

Would assume they want to confirm it works before starting the trip to the ISS. This is a new nose cone so never been tried before.

Quote from: AU1.52 on 03/01/2019 04:20 pm

Quote from: envy887 on 02/28/2019 12:05 pm
Quote from: FutureSpaceTourist on 02/27/2019 08:28 pm
...
Quote
LAUNCH, LANDING AND DRAGON DEPLOYMENT
(all times are approximate)
Hour/Min/Sec   Events
+00:00:58   Max Q (moment of peak mechanical stress on the rocket)
+00:02:33   1st stage main engine cutoff (MECO)
+00:02:38   1st and 2nd stages separate
+00:02:44   2nd stage engine starts
+00:07:48   1st stage entry burn
+00:08:57   2nd stage engine cutoff (SECO-1)
+00:09:26   1st stage entry burn
+00:09:37   1st stage landing
+00:10:59   Crew Dragon separates from 2nd stage
+00:12:00   Dragon nosecone open sequence begins

Why are there 2 first stage entry burns? From the listed times, the 2nd one should be the landing burn, although 11 seconds is a short landing burn. Usually those are 30 sec for a single engine landing.

Also do we know why they are opening the nose cone so early? Would not keeping it closed be an extra protection from MMOD possible damage to the dock? Are they opening it early to check they can open it?