Author Topic: Should Crew Dragon have ability to use SuperDracos for landing emergency?  (Read 57524 times)

Offline envy887

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Boeing has found a way to return its crew without its escape propellant still aboard.  Apollo did it.  Soyuz does it.  Shenzhou too.  Etc.

 - Ed Kyle

So you would propose that SpaceX put everything on hold and radically redesign their capsule so that the LAS is jettisonable at some point before reentry.

Additionally, what happens if this new LAS fails to jettison?

Presumably the same thing that would happen to Starliner, Apollo, Soyuz, and Shenzhou -- loss of vehicle and crew. Starliner would be able to enter orbit and complete its mission, but I presume it would be unstable when it hit the atmosphere and therefore would tumble, probably break apart. Apollo, Soyuz, and Shenzhou would have been unable to complete their missions or reenter safely, and certainly would not have been able to deploy their parachutes.

additionally the de-orbit burn for the various spacecraft are located where:
1. dragon 2 - in reentering spacecraft
2. Soyuz - in trunk?
3. Apollo - in trunk?
4. Shenzhou - in trunk?

If yes to 2-4. Then after they are committed to reentry (from the burn) they must separate trunk or die.

It's called a service module on those vehicles. And sep failure isn't necessarily LOCV. I believe Soyuz has had several SM sep failures and the vehicle and crew landed mostly intact.

Offline whitelancer64

Boeing has found a way to return its crew without its escape propellant still aboard.  Apollo did it.  Soyuz does it.  Shenzhou too.  Etc.

 - Ed Kyle

So you would propose that SpaceX put everything on hold and radically redesign their capsule so that the LAS is jettisonable at some point before reentry.

Additionally, what happens if this new LAS fails to jettison?

Presumably the same thing that would happen to Starliner, Apollo, Soyuz, and Shenzhou -- loss of vehicle and crew. Starliner would be able to enter orbit and complete its mission, but I presume it would be unstable when it hit the atmosphere and therefore would tumble, probably break apart. Apollo, Soyuz, and Shenzhou would have been unable to complete their missions or reenter safely, and certainly would not have been able to deploy their parachutes.

additionally the de-orbit burn for the various spacecraft are located where:
1. dragon 2 - in reentering spacecraft
2. Soyuz - in trunk?
3. Apollo - in trunk?
4. Shenzhou - in trunk?

If yes to 2-4. Then after they are committed to reentry (from the burn) they must separate trunk or die.

I was thinking more of the fact that the LAS is built into the fairings for both Soyuz and Shenzhou. Apollo had a boost-protective cover that was part of the LAS which covered the entire CM, which would have similarly prevented parachute deployment. And yes, all three had / have service modules which perform the deorbit burns, and separation from them is also a mission-critical event.
"One bit of advice: it is important to view knowledge as sort of a semantic tree -- make sure you understand the fundamental principles, ie the trunk and big branches, before you get into the leaves/details or there is nothing for them to hang on to." - Elon Musk
"There are lies, damned lies, and launch schedules." - Larry J

Offline woods170

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My question is: why do you consider returning to Earth with hypergolic propellant in close proximity to the crew anymore (or less) desirable than having the crew in close proximity of hypergolic propellants during launch, on-orbit operations or landing on the Moon?

Merely pointing out that prior spacecraft did it differently does not adequately explain your earlier post. You must have a reason. But you haven't provided the reason.
First, which is riskier, Dragon 2 descending with substantial abort propellant or Starliner without?
 
Second, and more important in my mind, is the increased landing mass due to the unused propellant - propellant that has no purpose after the first few minutes of flight.  It is a waste to orbit this mass - and to return it to Earth unused.  The extra mass means less useful payload mass to orbit, and it makes the landing more complicated and risky than it need be.

 - Ed Kyle
Good, now you are giving the reasons you should have given in your original post. Thank you.

Having said that I will notice that the bit about waste mass to orbit applies equally to Starliner. It also lifts its abort propellant all the way to orbit. So, in the discussion about propellant coming back down to Earth, it is invalid argument to support your case.

Offline clongton

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What SHOULD have happened once it became apparent that NASA was too risk-averse to allow propulsive landing, even though it had accepted propulsive landing in including SpaceX's Dragon design as a winner in the first place, was for SpaceX to immediately redesign the Spacecraft/Trunk interface to move the SD abort motors and abort propellant into the forward end of a slightly lengthened trunk. SpaceX has made more drastic changes than this in the past, with little lose to schedule, so there is no acceptable reason as to why Mr. Musk  did not do this. Perhaps he still hoped to make Dragon's propulsive landing available for non-NASA missions, or maybe he was unwilling for the SDs to be expendable, or he wanted to use Dragon as a lunar or Mars logistics lander or for some other reason. But the bottom line is that Dragon's abort capability should have been immediately relocated from the spacecraft into the trunk.

Personally I was very disappointed that Mr. Musk didn't fight NASA on this issue, tooth and nail, because in the beginning NASA accepted propulsive landing of Dragon. Propulsive landing absolutely is the right thing to do. SpaceX spent a great deal of money and time perfecting the design, only to have NASA develop cold feet and hide that fear behind a monumental mountain of paperwork to certify the system. Be that as it may, once it was clear that propulsive landing was no longer an option for Dragon, Mr. Musk should have relocated the abort system to the trunk, where it would have been left behind before reentry. Only 3 parachutes needed. Problem solved
« Last Edit: 10/08/2019 09:58 pm by clongton »
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Offline whitelancer64

What SHOULD have happened once it became apparent that NASA was too risk-averse to allow propulsive landing, even though it had accepted propulsive landing in including SpaceX's Dragon design as a winner in the first place, was for SpaceX to immediately redesign the Spacecraft/Trunk interface to move the SD abort motors and abort propellant into the forward end of a slightly lengthened trunk. SpaceX has made more drastic changes than this in the past, with little lose to schedule, so there is no acceptable reason as to why Mr. Musk  did not do this. Perhaps he still hoped to make Dragon's propulsive landing available for non-NASA missions, or maybe he was unwilling for the SDs to be expendable, or he wanted to use Dragon as a lunar or Mars logistics lander or for some other reason. But the bottom line is that Dragon's abort capability should have been immediately relocated from the spacecraft into the trunk.

Personally I was very disappointed that Mr. Musk didn't fight NASA on this issue, tooth and nail, because in the beginning NASA accepted propulsive landing of Dragon. Propulsive landing absolutely is the right thing to do. SpaceX spent a great deal of money and time perfecting the design, only to have NASA develop cold feet and hide that fear behind a monumental mountain of paperwork to certify the system. Be that as it may, once it was clear that propulsive landing was no longer an option for Dragon, Mr. Musk should have relocated the abort system to the trunk, where it would have been left behind before reentry. Only 3 parachutes needed. Problem solved

Perhaps you'd forgotten - propulsive landing was cancelled in mid 2017. FAR too late in the design process for that kind of a radical redesign. The pressure vessels for Demo-1 and Demo-2 Dragons and their Trunks were already well in production. The CR for the Demo-1 flight test was already completed and was scheduled for less than a year away.
"One bit of advice: it is important to view knowledge as sort of a semantic tree -- make sure you understand the fundamental principles, ie the trunk and big branches, before you get into the leaves/details or there is nothing for them to hang on to." - Elon Musk
"There are lies, damned lies, and launch schedules." - Larry J

Offline clongton

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Perhaps you'd forgotten - propulsive landing was cancelled in mid 2017. FAR too late in the design process for that kind of a radical redesign. The pressure vessels for Demo-1 and Demo-2 Dragons and their Trunks were already well in production. The CR for the Demo-1 flight test was already completed and was scheduled for less than a year away.

No, I hadn't forgotten. It is still what should have happened. Mr. Musk should have called out NASA on its bullcrap, then make the design change AND make NASA pay for it. Schedule would likely be pretty much where it is today. How much time has been lost so far dealing with parachute redesign, and the explosive loss of the IFA spacecraft? We'd probably be looking at today's schedule with a different Dragon.
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I started my career on the Saturn-V F-1A engine

Offline whitelancer64

Perhaps you'd forgotten - propulsive landing was cancelled in mid 2017. FAR too late in the design process for that kind of a radical redesign. The pressure vessels for Demo-1 and Demo-2 Dragons and their Trunks were already well in production. The CR for the Demo-1 flight test was already completed and was scheduled for less than a year away.

No, I hadn't forgotten. It is still what should have happened. Mr. Musk should have called out NASA on its bullcrap, then make the design change AND make NASA pay for it. Schedule would likely be pretty much where it is today. How much time has been lost so far dealing with parachute redesign, and the explosive loss of the IFA spacecraft? We'd probably be looking at today's schedule with a different Dragon.

How would NASA pay for it? Fixed price, not cost-plus....

Hindsight is 20/20. No way to know then that parachutes and SuperDraco were going to be such a problem.
« Last Edit: 10/08/2019 10:30 pm by whitelancer64 »
"One bit of advice: it is important to view knowledge as sort of a semantic tree -- make sure you understand the fundamental principles, ie the trunk and big branches, before you get into the leaves/details or there is nothing for them to hang on to." - Elon Musk
"There are lies, damned lies, and launch schedules." - Larry J

Offline clongton

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How would NASA pay for it? Fixed price, not cost-plus....

Doesn't matter. Customer ALWAYS pays for major design changes that IT is responsible for causing. There are literally tens of thousands of examples in many industries of this. It's established fact.
Chuck - DIRECT co-founder
I started my career on the Saturn-V F-1A engine

Offline theinternetftw

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How much time has been lost so far dealing with parachute redesign, and the explosive loss of the IFA spacecraft?

Is there any reason why the explosion wouldn't have happened if the SDs were in the trunk?

For reference, the explosion happened due to NTO making its way past a check valve during fueling ops.  No mention has been made to reuse causing this leak.  See the anomaly statement.
« Last Edit: 10/09/2019 04:56 am by theinternetftw »

Offline woods170

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What SHOULD have happened once it became apparent that NASA was too risk-averse to allow propulsive landing, even though it had accepted propulsive landing in including SpaceX's Dragon design as a winner in the first place, was for SpaceX to immediately redesign the Spacecraft/Trunk interface to move the SD abort motors and abort propellant into the forward end of a slightly lengthened trunk. SpaceX has made more drastic changes than this in the past, with little lose to schedule, so there is no acceptable reason as to why Mr. Musk  did not do this. Perhaps he still hoped to make Dragon's propulsive landing available for non-NASA missions, or maybe he was unwilling for the SDs to be expendable, or he wanted to use Dragon as a lunar or Mars logistics lander or for some other reason. But the bottom line is that Dragon's abort capability should have been immediately relocated from the spacecraft into the trunk.

Personally I was very disappointed that Mr. Musk didn't fight NASA on this issue, tooth and nail, because in the beginning NASA accepted propulsive landing of Dragon. Propulsive landing absolutely is the right thing to do. SpaceX spent a great deal of money and time perfecting the design, only to have NASA develop cold feet and hide that fear behind a monumental mountain of paperwork to certify the system. Be that as it may, once it was clear that propulsive landing was no longer an option for Dragon, Mr. Musk should have relocated the abort system to the trunk, where it would have been left behind before reentry. Only 3 parachutes needed. Problem solved

You are forgetting a few details here Chuck.

Most importantly: NASA did not outright forbid the use of propulsive landing. They accepted SpaceX's offer for CCtCAP WITH propulsive landing. It being a novel technology NASA set an initial set of requirements which basically directed SpaceX to demonstrate the basic idea behind propulsive landing. Only after the basic idea had been demonstrated would NASA allow SpaceX to continue full development.

We have all witnessed the results of those initial demonstrations: Crew Dragon performing static fire tests of the SuperDracos as well as the hover tests (while suspended from a crane).

The results of those initial demonstrations were so successful that SpaceX wanted to proceed full steam with development of propulsive landing. NASA on the other hand panicked. They had more-or-less anticipated that the initial demonstrations would show that propulsive landing was NOT viable.
SpaceX actually requesting to proceed with propulsive landing was NOT what NASA wanted, but NASA had to comply, in accordance with the rules set by the CCtCAP contract.

However: there was a way out for NASA. NASA had secured the contractual right to set the requirements for propulsive landing. And that is what they did: they produced a set of requirements so vast and demanding that SpaceX quickly recognized that in no way would SpaceX be able to satisfy those requirements within the budget set for CCtCAP.

So what happened is that for almost three years after awarding the CCtCAP contracts NASA made SpaceX believe that propulsive landing was something they might actually end up using. So for three years development of Crew Dragon proceeded full steam ahead WITH SuperDracos baselined to be on the Crew Module.
By the time SpaceX had to throw in the towel - due to the mountain of NASA requirements - there was zero chance that SpaceX would reverse and radically alter the design of Crew Dragon. It was simply too late in the game. The design had gone thru several required reviews and hardware was being built.


Crew Dragon was also supposed to be used - in a derivative form - for the Red Dragon mission. Which very much required the SuperDraco's to be located on the Crew Module.

And there was the prospect of flying non-NASA crewed missions which would have done propulsive landing (no need to certify a system to NASA requirements when it is not being used for a NASA mission).

Plenty reasons why SuperDracos remained on the Crew Module.

Also: hindsight is always 20-20.
« Last Edit: 10/09/2019 07:31 am by woods170 »

Offline Semmel

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What SHOULD have happened once it became apparent that NASA was too risk-averse to allow propulsive landing, even though it had accepted propulsive landing in including SpaceX's Dragon design as a winner in the first place, was for SpaceX to immediately redesign the Spacecraft/Trunk interface to move the SD abort motors and abort propellant into the forward end of a slightly lengthened trunk. SpaceX has made more drastic changes than this in the past, with little lose to schedule, so there is no acceptable reason as to why Mr. Musk  did not do this. Perhaps he still hoped to make Dragon's propulsive landing available for non-NASA missions, or maybe he was unwilling for the SDs to be expendable, or he wanted to use Dragon as a lunar or Mars logistics lander or for some other reason. But the bottom line is that Dragon's abort capability should have been immediately relocated from the spacecraft into the trunk.

Personally I was very disappointed that Mr. Musk didn't fight NASA on this issue, tooth and nail, because in the beginning NASA accepted propulsive landing of Dragon. Propulsive landing absolutely is the right thing to do. SpaceX spent a great deal of money and time perfecting the design, only to have NASA develop cold feet and hide that fear behind a monumental mountain of paperwork to certify the system. Be that as it may, once it was clear that propulsive landing was no longer an option for Dragon, Mr. Musk should have relocated the abort system to the trunk, where it would have been left behind before reentry. Only 3 parachutes needed. Problem solved

You are forgetting a few details here Chuck.

Most importantly: NASA did not outright forbid the use of propulsive landing. They accepted SpaceX's offer for CCtCAP WITH propulsive landing. It being a novel technology NASA set an initial set of requirements which basically directed SpaceX to demonstrate the basic idea behind propulsive landing. Only after the basic idea had been demonstrated would NASA allow SpaceX to continue full development.

We have all witnessed the results of those initial demonstrations: Crew Dragon performing static fire tests of the SuperDracos as well as the hover tests (while suspended from a crane).

The results of those initial demonstrations were so successful that SpaceX wanted to proceed full steam with development of propulsive landing. NASA on the other hand panicked. They had more-or-less anticipated that the initial demonstrations would show that propulsive landing was NOT viable.
SpaceX actually requesting to proceed with propulsive landing was NOT what NASA wanted, but NASA had to comply, in accordance with the rules set by the CCtCAP contract.

However: there was a way out for NASA. NASA had secured the contractual right to set the requirements for propulsive landing. And that is what they did: they produced a set of requirements so vast and demanding that SpaceX quickly recognized that in no way would SpaceX be able to satisfy those requirements within the budget set for CCtCAP.

So what happened is that for almost three years after awarding the CCtCAP contracts NASA made SpaceX believe that propulsive landing was something they might actually end up using. So for three years development of Crew Dragon proceeded full steam ahead WITH SuperDracos baselined to be on the Crew Module.
By the time SpaceX had to throw in the towel - due to the mountain of NASA requirements - there was zero chance that SpaceX would reverse and radically alter the design of Crew Dragon. It was simply too late in the game. The design had gone thru several required reviews and hardware was being built.


Crew Dragon was also supposed to be used - in a derivative form - for the Red Dragon mission. Which very much required the SuperDraco's to be located on the Crew Module.

And there was the prospect of flying non-NASA crewed missions which would have done propulsive landing (no need to certify a system to NASA requirements when it is not being used for a NASA mission).

Plenty reasons why SuperDracos remained on the Crew Module.

Also: hindsight is always 20-20.

I think you both are right. If the initial contract didnt limit the amount of requirements that can be asked of any of the contenders, then this is a bug in the contract. It should not be legal because it gives one side arbitrary power. You could just in the same way argue that SpaceX would have the right to waive any requirement they want. No one in their right mind would sign such a contract.

This sort of shenanigans convinced SpaceX that NASA will not have "insight and oversight" on Starship. NASA lost more long term than SpaceX lost short term.


My own view on it with an analogy:
Dragon2 is was designed as a 4-wheel race car in a 3-wheel race. Everybody thought that using 4 wheels is stupid and sure to fail but when it didnt fail, the race master got scared. So they demanded so many requirements on the 4-wheeler that they rather chopped off one wheel than comply with the requirements. Now Dragon2 is the maimed 3-wheel race car in a 3-wheel race that was designed as a 4-wheel vehicle. It will never be right.
Now there will be a new race, sporting 4-wheel race cars and none of the 3-wheelers stand a chance.

Offline dondar

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I guess weíre going down the rabbit hole of ever decreasing likelihood and inefficient mitigation measures to address the final minute risks, itís a NASA thing.

Exactly. Compare today's NASA to 1960's NASA. The difference is extreme.


Every other capsule has only got parachutes for landing (soyuz touchdown solids excluded)
The Soyuz solids are only there to soften the blow. They are not critical for a safe landing. If they fail the crew still walks away from the capsule in one piece.

Nasa is paying for the ride so if they want the SDs shut down for EDL thatís ok.

That's not quite what was going on. NASA didn't order SpaceX to disable the SDs for EDL. What they basiscally said was this: "OK Elon, looks like those SDs can do the job. Now here's our list of requirements before we sign off on them". And then NASA stepped aside to reveal a Mount Everest sized pile of requirements.

Understandably, SpaceX dropped the SDs for landing there and then.
Emphasis mine.  The Soyuz retro rockets are for comfort measures only?  Interesting.
It depends on what you call by comfort.

Soyuz-35 had such hard landing (the altimeter lens remained covered during final decent and as a result retro-rockets had never fired). While Cosmonauts did experience 30-g forces during landing shock they had both walked out without external help.
One of these cosmonauts was Valeri Kubasov  btw.
Due to it's "insignificance" the event is pretty much forgotten.
Which is a pity, the Russians had redesigned not only the gamma-ray altimeter but also crew chairs and capsule crash structure.
And eventually they got "tested" it fully. Due to electrical failure retro-rockets of Soyuz TM-25 reacted too early at the attitude of 5km and the capsule had to crash land using parachutes only. No health issues for the crew either.

But! the Russians had also experienced a number of ballistic reentries. Such descends cause not only higher approach speeds and harder de-accelerations but also landings in random places (in Russian case often mountains) where use of retro-rockets could be critical for crew survival. It is an important feature which always helps and could be life saving.


While pilots get often injured in ejection events (~20g if not lucky) they sit very differently and that matters very very much.
 Crew chairs, not surprisingly looking very much alike in all existing landing crafts, are specially designed to absorb vertical g-forces.

Offline clongton

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Crew Dragon was also supposed to be used - in a derivative form - for the Red Dragon mission. Which very much required the SuperDraco's to be located on the Crew Module.

NASA had to know that as soon as they published the monumental amount of work SpaceX had to do to certify propulsive landing that Red Dragon was immediately - instantly - dead as a door nail. Red Dragon could have put instrumentation or logistics on the Martian surface almost on demand launched by a rocket that could be built and flown by the dozens faster and cheaper than NASA could do even one. NASA itself killed that with its unjustifiable fear toward propulsive landing. Remember it was NASA back in the 1960s that created and perfected propulsive landing when it created the Apollo LM. Then it totally lost its nerve and is now unbelievably frightened at doing that again.

NASA lost more than SpaceX did when it pulled that crap. As grateful as SpaceX is - and always will be - for NASA's confidence in giving them a CRS contract that saved the company, SpaceX will never again allow NASA oversight at a fixed price basis into any of its space endeavors - ever. Going forward NASA will never again be anything but a paying customer on a SpaceX flight. If NASA doesn't like something about what SpaceX is doing then they can just go get themselves another ride from somebody else. And I promise you that Blue Origin (the other ride), who needs NASA money even less than SpaceX ever did, will never go down that rabbit hole, now that NASA has exposed itself for being the mere shadow of the great organization it once was. There is no vision left at NASA anymore and that has got to drive Musk and Bezos crazy because both of their companies are led by men of great vision. While NASA wastes its time and money on videos showing all the wonderful things it is going to be doing someday as they (cough) return humans to the moon (cough) once SLS gets to fly someday, Musk will be on the lunar surface building a permanent base or 2 there.

Nope, NASA lost more than SpaceX did when it pulled that propulsive landing crap.
« Last Edit: 10/09/2019 03:47 pm by clongton »
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Offline eriblo

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What SHOULD have happened once it became apparent that NASA was too risk-averse to allow propulsive landing, even though it had accepted propulsive landing in including SpaceX's Dragon design as a winner in the first place, was for SpaceX to immediately redesign the Spacecraft/Trunk interface to move the SD abort motors and abort propellant into the forward end of a slightly lengthened trunk. SpaceX has made more drastic changes than this in the past, with little lose to schedule, so there is no acceptable reason as to why Mr. Musk  did not do this. Perhaps he still hoped to make Dragon's propulsive landing available for non-NASA missions, or maybe he was unwilling for the SDs to be expendable, or he wanted to use Dragon as a lunar or Mars logistics lander or for some other reason. But the bottom line is that Dragon's abort capability should have been immediately relocated from the spacecraft into the trunk.

Personally I was very disappointed that Mr. Musk didn't fight NASA on this issue, tooth and nail, because in the beginning NASA accepted propulsive landing of Dragon. Propulsive landing absolutely is the right thing to do. SpaceX spent a great deal of money and time perfecting the design, only to have NASA develop cold feet and hide that fear behind a monumental mountain of paperwork to certify the system. Be that as it may, once it was clear that propulsive landing was no longer an option for Dragon, Mr. Musk should have relocated the abort system to the trunk, where it would have been left behind before reentry. Only 3 parachutes needed. Problem solved
Most abort propellant is also the orbital maneuvering propellant ("you need either, not both"), so this would also have led to an increase in total propellant load and vehicle mass. Most of the hazard and mass problems with on board propellant would have remained but would now occur after an abort instead of a nominal reentry. You would discard the SDs and their associated plumbing making potential crewed reuse more expensive.

Offline clongton

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1. Most abort propellant is also the orbital maneuvering propellant ("you need either, not both"), so this would also have led to an increase in total propellant load and vehicle mass. Most of the hazard and mass problems with on board propellant would have remained but would now occur after an abort instead of a nominal reentry.
2. You would discard the SDs and their associated plumbing making potential crewed reuse more expensive.

1. The total propellant load already included everything the spacecraft needed for both Draco and Super Draco use. There would not have been any additional propellant needed.
2. NASA already demanded a brand new spacecraft for each mission. By contract no spacecraft reuse was allowed.
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Offline eriblo

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1. Most abort propellant is also the orbital maneuvering propellant ("you need either, not both"), so this would also have led to an increase in total propellant load and vehicle mass. Most of the hazard and mass problems with on board propellant would have remained but would now occur after an abort instead of a nominal reentry.
2. You would discard the SDs and their associated plumbing making potential crewed reuse more expensive.

1. The total propellant load already included everything the spacecraft needed for both Draco and Super Draco use. There would not have been any additional propellant needed.
2. NASA already demanded a brand new spacecraft for each mission. By contract no spacecraft reuse was allowed.
1. Yes, but in that case you have either redesigned and moved the whole propulsion system to the trunk or you are running hypergolic plumbing from the trunk to the Dracos on the capsule.
2. Yes, but it would have had implications for CRS2 prices as well as potential future orders of crewed flights for NASA or other customers.

Offline woods170

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Crew Dragon was also supposed to be used - in a derivative form - for the Red Dragon mission. Which very much required the SuperDraco's to be located on the Crew Module.

NASA had to know that as soon as they published the monumental amount of work SpaceX had to do to certify propulsive landing that Red Dragon was immediately - instantly - dead as a door nail.

Correct. But NASA is not monolithic in nature. It was NASA HQ and the CCP office that chickened out of propulsive landing. Other parts of NASA were excited as hell about Red Dragon and were actively working with SpaceX to make it happen. Those parts of NASA had the door slammed in their faces by their colleagues from HQ and CCP. I know from feedback from NASA sources that they were pretty upset about it.

But that particular little episode was hardly the first time that one part of NASA shot another part of NASA in the foot. It has happened plenty of times. And given how NASA still operates it will happen again in the future.

Offline Oli

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NASA had to know that as soon as they published the monumental amount of work SpaceX had to do to certify propulsive landing that Red Dragon was immediately - instantly - dead as a door nail.

Why? Surely unmanned landing on Mars would have been substantially different and would only have had to be as safe as any other Mars landing before it.

Red Dragon could have put instrumentation or logistics on the Martian surface almost on demand launched by a rocket that could be built and flown by the dozens faster and cheaper than NASA could do even one.

There's no basis whatsoever for this claim.

SpaceX will never again allow NASA oversight at a fixed price basis into any of its space endeavors - ever.

We'll see about that.
« Last Edit: 10/09/2019 06:23 pm by Oli »

Offline clongton

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I know from feedback from NASA sources that they were pretty upset about it.

I got the same feedback.
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Offline Spindog

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Quite possible that a multiple failure scenario would involve 2 or more chutes tangling with each other? I dont know but I would presume that impact with the water on only 2 of the 4 chutes would be rather dangerous. I would think that any scenario with dangerous, injury causing, or capsule damaging (and potentially sinking) impact speeds would call for some SD firing even if only to cushion the blow.

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