SpaceX Falcon 9 / Dragon 2 : SpX-DM1 : March 2, 2019 : DISCUSSION

[joek]

That means that SpaceX could build up a stockpile of used Crew Dragons that could potentially be used for private missions.  Could they be used for propulsive landing flight tests?

More likely for cargo (if they use refurb Dragons) as Dragon 2 (cargo version) will be used for CRS-2.

[hpras]

Splashdown !

SpaceX have posted a higher-res version of splashdown on their website (attached).

Despite claims up-thread, one can see from the closeness of the base of Dragon to the horizon, this video was not shot from a plane at 18k ft as claimed.
From 18 kft, the horizon is over 250 km away.
Plus the video was more stable and from a more constant distance and angle than is possible from a moving plane.

That last video segment with the actual splashdown seemed to me very much like it was being shot from one of the recovery vessels. The IR tracking video segments from plasma trail through drogue chute deployment were clearly shot by a stabilized camera mounted on the NASA WB-52 flying at roughly 18K feet, as the aircraft altitude was displayed in the upper right corner the whole time.

I saw the 18.000.... I thought it might be meters.

[Lars-J]

Under the side hatch is an open hatch. This photo taken from NASA video shows water sloshing in the bottom of the compartment. I’d like to know what was in there and when did it open.

thats the main parachute compartment.

I was pretty disgusted seeing seawater sloshing around in there.

Disgusted? Really? What did you expect?

[tyrred]

Splashdown !

SpaceX have posted a higher-res version of splashdown on their website (attached).

Despite claims up-thread, one can see from the closeness of the base of Dragon to the horizon, this video was not shot from a plane at 18k ft as claimed.
From 18 kft, the horizon is over 250 km away.
Plus the video was more stable and from a more constant distance and angle than is possible from a moving plane.

That last video segment with the actual splashdown seemed to me very much like it was being shot from one of the recovery vessels. The IR tracking video segments from plasma trail through drogue chute deployment were clearly shot by a stabilized camera mounted on the NASA WB-52 flying at roughly 18K feet, as the aircraft altitude was displayed in the upper right corner the whole time.

Agreed, with minor nitpick... It was a NASA WB-57.

[su27k]

Very thoughtful of them to have a bridge connecting the side door of the Dragon to the door of the astronaut quarter on the ship, not as cool looking as CAA but pretty useful for getting astronaut out of Dragon.

Photo Credit: Tom Cross

[CuddlyRocket]

That means that SpaceX could build up a stockpile of used Crew Dragons that could potentially be used for private missions.  Could they be used for propulsive landing flight tests?

More likely for cargo (if they use refurb Dragons) as Dragon 2 (cargo version) will be used for CRS-2.

They could be used for propulsive landing flight tests, but they won't because Starship is the next big thing. Equipment from the Crew Dragon stockpile can probably be removed and reused (the seats, for instance).

[TrevorMonty]

I don't think propulsive landing with crew is off table ,  just to difficult to prove to NASA in time they had. Cargo missions would be ideal for building confidence in it, problem is asking NASA to risk its precious science cargo.

If they want to do commercial HSF with Dragon 2 then propulsive landing is worth going for. Cost savings per mission are significant compared to new capsule, plus quicker turn around time between missions.

[kevinof]

Think you're spot on here.

So the D2 doesn't have legs or airbags (like Starliner). Question is - if they had to, could they do a land landing on the heatshield using chutes and then the SD's  in the final metres?

Is the cost of a refurb of the shield less than a water landing refurb? If Starship gets delayed and they have commercial opportunities outside Nasa for D2 rides, maybe this would be worth investing in.

I don't think propulsive landing with crew is off table ,  just to difficult to prove to NASA in time they had. Cargo missions would be ideal for building confidence in it, problem is asking NASA to risk its precious science cargo.

If they want to do commercial HSF with Dragon 2 then propulsive landing is worth going for. Cost savings per mission are significant compared to new capsule, plus quicker turn around time between missions.

[Alexphysics]

Guys, there's a thread for that on the general SpaceX section

[Zed_Noir]

Very thoughtful of them to have a bridge connecting the side door of the Dragon to the door of the astronaut quarter on the ship, not as cool looking as CAA but pretty useful for getting astronaut out of Dragon.

Think the bridge connection is more for a gurney than the crew. Since that hatch on the ship in the photo probably goes directly to the shipboard medical facility.

[Rocket Science]

https://arstechnica.com/science/2019/03/with-dragon-russian-critic-says-roscosmos-acting-left-behind/

[CorvusCorax]

So the D2 doesn't have legs or airbags (like Starliner). Question is - if they had to, could they do a land landing on the heatshield using chutes and then the SD's  in the final metres?

They certainly could. Although I doubt the heatshield would be of much use afterwards. It's not designed for mechanical point stress as would happen when landing on land. That likely wouldn't affect the rest of the capsule though, and if the heatshield needs to be replaced anyway, it doesn't matter.

Btw, starliner jettisons the heatshield before touchdown!

[jerwah]

Btw, starliner jettisons the heatshield before touchdown!

Elon tweeted last night that propulsive landings of cargo "should be no problem"

We know there aren't any feet holes in the current heat shield design.

I've always felt that dropping the heat shield was a viable solution to the not wanting holes in the heatshield concern.

<rampant speculation warning>
One interpretation of Elon's tweet is that they still want to try and do cargo landings propulsively.

It would make sense that they don't want to have to create two different heat shield designs, (holes and no holes) therefore a jettisonable heat shield of the no holes design could be used on the cargo variants after refurbishment.

You could test this system with cargo return, water landings at first, with almost no additional risk to NASA  (since they would be expecting water landings anyway)
</rampant speculation warning>

[Herb Schaltegger]

Agreed, with minor nitpick... It was a NASA WB-57.

Yep, typo.

[freddo411]

Btw, starliner jettisons the heatshield before touchdown!

Elon tweeted last night that propulsive landings of cargo "should be no problem"

We know there aren't any feet holes in the current heat shield design.

I've always felt that dropping the heat shield was a viable solution to the not wanting holes in the heatshield concern.

<rampant speculation warning>
One interpretation of Elon's tweet is that they still want to try and do cargo landings propulsively.

It would make sense that they don't want to have to create two different heat shield designs, (holes and no holes) therefore a jettisonable heat shield of the no holes design could be used on the cargo variants after refurbishment.

You could test this system with cargo return, water landings at first, with almost no additional risk to NASA  (since they would be expecting water landings anyway)
</rampant speculation warning>

SpaceX could design legs that extended thought the sides of the capsule; breaking thru the pica-x only after reentry -- much like aperture to the parachute compartment and parachute cord pathways.    No need to change the bottom heat shield at all.

[TrevorMonty]

Btw, starliner jettisons the heatshield before touchdown!

Elon tweeted last night that propulsive landings of cargo "should be no problem"

We know there aren't any feet holes in the current heat shield design.

I've always felt that dropping the heat shield was a viable solution to the not wanting holes in the heatshield concern.

<rampant speculation warning>
One interpretation of Elon's tweet is that they still want to try and do cargo landings propulsively.

It would make sense that they don't want to have to create two different heat shield designs, (holes and no holes) therefore a jettisonable heat shield of the no holes design could be used on the cargo variants after refurbishment.

You could test this system with cargo return, water landings at first, with almost no additional risk to NASA  (since they would be expecting water landings anyway)
</rampant speculation warning>

SpaceX could design legs that extended thought the sides of the capsule; breaking thru the pica-x only after reentry -- much like aperture to the parachute compartment and parachute cord pathways.    No need to change the bottom heat shield at all.

You mean deploy on outside of shield, similar to how NS does it.

[freddo411]

Btw, starliner jettisons the heatshield before touchdown!

Elon tweeted last night that propulsive landings of cargo "should be no problem"

We know there aren't any feet holes in the current heat shield design.

I've always felt that dropping the heat shield was a viable solution to the not wanting holes in the heatshield concern.

<rampant speculation warning>
One interpretation of Elon's tweet is that they still want to try and do cargo landings propulsively.

It would make sense that they don't want to have to create two different heat shield designs, (holes and no holes) therefore a jettisonable heat shield of the no holes design could be used on the cargo variants after refurbishment.

You could test this system with cargo return, water landings at first, with almost no additional risk to NASA  (since they would be expecting water landings anyway)
</rampant speculation warning>

  Yes, something akin to that
SpaceX could design legs that extended thought the sides of the capsule; breaking thru the pica-x only after reentry -- much like aperture to the parachute compartment and parachute cord pathways.    No need to change the bottom heat shield at all.

You mean deploy on outside of shield, similar to how NS does it.

[Vettedrmr]

Have we heard anything from NASA/SpaceX about the performance and interaction of the 4 chutes? 

Have a good one,
Mike

[deruch]

Have we heard anything from NASA/SpaceX about the performance and interaction of the 4 chutes? 

No.  Probably will have to wait for the next ASAP meeting to see if it gets discussed.  I don't think we're likely to get many specific statements from SpaceX or NASA on technical matters or systems performance beyond just, "Everything went well."  Or generalizations about "few minor issues being worked through," etc.

[Lars-J]

Have we heard anything from NASA/SpaceX about the performance and interaction of the 4 chutes? 

No.  Probably will have to wait for the next ASAP meeting to see if it gets discussed.  I don't think we're likely to get many specific statements from SpaceX or NASA on technical matters or systems performance beyond just, "Everything went well."  Or generalizations about "few minor issues being worked through," etc.

The more chutes you add the more weird interactions between them you are liable to get. Even ASAP should realize that eventually.