SpaceX Dragon 2 Updates and Discussion - Thread 3

[SWGlassPit]

Static fire slo-mo video

https://twitter.com/commercial_crew/status/1197173732034396160

#ICYMI 🐉 Last week, @SpaceX completed a series of static fire engine tests of the #CrewDragon spacecraft.

The tests will help validate the launch escape system for the in-flight abort demonstration planned as part of @NASA's Commercial Crew Program.

💻: go.nasa.gov/2XjdMRq

That's a beautiful video to watch.

[BrianPeterson]

Propulsive landing would have been trickier than this? @NASA

Propulsive landings are impossible,NASA said no.

NASA is highly risk averse. Propulsive landings is something no crewed craft has ever done and they don't even want to try. Parachutes are 100 year old tech and no one has ever died on a NASA craft landing by Parachute, so... THey don't want to stray far from what they know. Elon on the other hand wants to drive the technology into the future.

50 years from now and decades of Starship landings and no one will blink an eye at the idea of propulsive landing.

[MichaelBlackbourn]

Propulsive landing would have been trickier than this? @NASA

Propulsive landings are impossible,NASA said no.

NASA is highly risk averse. Propulsive landings is something no crewed craft has ever done and they don't even want to try. Parachutes are 100 year old tech and no one has ever died on a NASA craft landing by Parachute, so... THey don't want to stray far from what they know. Elon on the other hand wants to drive the technology into the future.

50 years from now and decades of Starship landings and no one will blink an eye at the idea of propulsive landing.

I think Armstrong and Aldrin, in addition to a few other would would disagree with the 'ever done' part.

[Ionmars]

Propulsive landing would have been trickier than this? @NASA

Propulsive landings are impossible,NASA said no.

NASA is highly risk averse. Propulsive landings is something no crewed craft has ever done and they don't even want to try. Parachutes are 100 year old tech and no one has ever died on a NASA craft landing by Parachute, so... THey don't want to stray far from what they know. Elon on the other hand wants to drive the technology into the future.

50 years from now and decades of Starship landings and no one will blink an eye at the idea of propulsive landing.

I think Armstrong and Aldrin, in addition to a few other would would disagree with the 'ever done' part.

Apollo landing on the moon was too risky and shouldna been done. 

[dror]

I am surprise that Spacex has still prove its parachute works.
CRS has almost 20 mission with no single parachute deployment failure.
If NASA would like to play fair, at least 5-10 Starliner cargo  launches to approve Boeing parachute functionality. Definitely after their fiasco with pad abort, suppose to be required to prove their safety.

The crew capsule is heavier and has a different chute design.  There have been parachute issues on CRS flights, they just didn't have any complete failures.  (The downmass allowed on CRS missions is actually set by the parachutes.)

Propulsive landing would have been trickier than this? @NASA

They would still have to have parachutes with propulsive landings, so no gain there, I think.

[Draggendrop]

I believe that propulsive landing is the future for many craft but may have been too much, too early (wrt HSF) for conservative acceptance.

That is fine.

Just a side note...Propulsive would have had chutes as a backup system. Presently we have chutes...with over capacity.

I would rather not quibble over it...

[Rocket Science]

Personally I would like to have seen more research done on the rotor concept for capsules see 2:40 (Tip of the hat to Roton and our friend  HMXHMX as well)

[punder]

Personally I would like to have seen more research done on the rotor concept for capsules see 2:40 (Tip of the hat to Roton and our friend  HMXHMX as well)

Ah, Roton. My first foray into radical amazing peopleism.   

[gongora]

This thread is starting to stray a bit.

[WindyCity]

I believe that propulsive landing is the future for many craft but may have been too much, too early (wrt HSF) for conservative acceptance..

If Starship succeeds, the argument against propulsive landing will be considerably weakened, I should think.

[Draggendrop]

I believe that propulsive landing is the future for many craft but may have been too much, too early (wrt HSF) for conservative acceptance..

If Starship succeeds, the argument against propulsive landing will be considerably weakened, I should think.

I agree and hopefully time will favour this method for all vendors.

[SWGlassPit]

I believe that propulsive landing is the future for many craft but may have been too much, too early (wrt HSF) for conservative acceptance.

That is fine.

Just a side note...Propulsive would have had chutes as a backup system. Presently we have chutes...with over capacity.

I would rather not quibble over it...

Side note to the side note: there are flight regimes in which parachutes would not have sufficient time to take over from a failing propulsion system.  I'm not sure how that one gets resolved.

[Robotbeat]

I believe that propulsive landing is the future for many craft but may have been too much, too early (wrt HSF) for conservative acceptance.

That is fine.

Just a side note...Propulsive would have had chutes as a backup system. Presently we have chutes...with over capacity.

I would rather not quibble over it...

Side note to the side note: there are flight regimes in which parachutes would not have sufficient time to take over from a failing propulsion system.  I'm not sure how that one gets resolved.

Test fire of the propulsive system high enough to be able to use the parachutes if there’s a problem.

[SWGlassPit]

Not all failures manifest early in a firing.  An uncaught propellant leak that causes early low-level cutoff, for example.

[happyflower]

A couple of questions

1. Will crew dragon be used again by NASA after its recovered now that SpaceX has made some changes to the superdraco system, or is each crew dragon used once only?

2. If NASA doesnt want the crew dragon after its mission, can spacex use it again for private use?

[kevinof]

No re-use for Nasa and yes, SpaceX can do whatever it wants with them after their flight.

A couple of questions

1. Will crew dragon be used again by NASA after its recovered now that SpaceX has made some changes to the superdraco system, or is each crew dragon used once only?

2. If NASA doesnt want the crew dragon after its mission, can spacex use it again for private use?

[snotis]

A couple of questions

1. Will crew dragon be used again by NASA after its recovered now that SpaceX has made some changes to the superdraco system, or is each crew dragon used once only?

2. If NASA doesnt want the crew dragon after its mission, can spacex use it again for private use?

NASA is not buying a rocket and a spacecraft from SpaceX.  They are basically buying a taxi ride to the ISS for 4 people.  So SpaceX can use the rocket (Falcon 9) and spacecraft (Crew Dragon) however they want after they get the job done.

[clongton]

Side note to the side note: there are flight regimes in which parachutes would not have sufficient time to take over from a failing propulsion system.  I'm not sure how that one gets resolved.

By realizing Elon's stated eventual goal: that spacecraft become as safe and reliable as today's aircraft.
Admittedly that will take time, but it is the ultimate answer to the question.

[Draggendrop]

I believe that both commercial crew providers will do well and complete their service for the ISS under chute use.

My statement was primarily for future vehicles, not restricted to earth, but also beyond LEO to other bodies for landing and liftoff.

I still think retro propulsion with a backup, is the way forward for many scenarios in the future.

as a side...chute use has been around for a very long time (well before WW2) and though has become much better now, is not fool proof.

I may have diverted the thread and apologize...I'll can it now...

[woods170]

A couple of questions

1. Will crew dragon be used again by NASA after its recovered now that SpaceX has made some changes to the superdraco system, or is each crew dragon used once only?

2. If NASA doesnt want the crew dragon after its mission, can spacex use it again for private use?

1. All seven currently manifested manned Crew Dragon missions (DM-1 and the six operational missions) are to use brand-new spacecraft. However, this may be subject to change once a few manned missions have flown. It all depends on how many additional missions NASA will order (now that ISS is likely to remain in orbit until 2030) and if NASA is willing to certify Crew Dragon for reuse, like they have done for cargo Dragon.

2. SpaceX is and remains the owner of each and every Crew Dragon spacecraft. They are not NASA property. Nor can NASA "want" the Crew Dragon after a flown mission.