SpaceX Dragon 2 Updates and Discussion - Thread 3

[DistantTemple]

Crew Dragon is a different build. Crew will not be converted to cargo.

The SpaceX plan was/is to reuse Crew Dragons for cargo, in part because NASA wouldn't allow their reuse for NASA crew.

Now they can so that is restriction is gone.

salpun, you have exactly contradicted yourself: "different build. Crew will not be converted to cargo." and "Now they can so that is restriction is gone."

Edit: added Bold...

[salpun]

They got the authorization today look back up the thread for the contract wording.

[Tulse]

The point I was trying to make is that SpaceX's original intent was to repurpose some Crew Dragons for cargo (since the new Cargo Dragons use the same Dragon 2 design, with the retirement of the Dragon 1). This would have allowed SpaceX to demonstrate that a Dragon 2 refurbished after being pulled out of salt water could nonetheless be safely reflown. I would have thought that NASA would have required at least one such reflight before agreeing to put crew onto a recovered Dragon.

That said, I don't know when PCM-2 is likely to take place, and I suppose SpaceX may have a few CRS missions prior in which they could demonstrate the reflight of either Endeavour or the PCM-1 Dragon.

[gongora]

Crew Dragon is a different build. Crew will not be converted to cargo.

The SpaceX plan was/is to reuse Crew Dragons for cargo, in part because NASA wouldn't allow their reuse for NASA crew.

That is not true.

[darkenfast]

I would say that common sense indicates that if there were to be any problems with the rest of the mission, then not only re-use, but scheduled missions would be affected.  It's not like NASA HAS to accept previously flown hardware if they feel something is wrong.  Giving the go-ahead now allows for both SpaceX and NASA to establish refurbishment and inspection procedures and for SpaceX to schedule production.  Remember, NASA has the data from not only the Demo-1 flight (same sidewall), but also all the data from the many previous uses of the heatshield on Cargo Dragon missions.

[Tulse]

That is not true.

Was there never any plan to refurbish used Crew Dragon vehicles for cargo runs? I have seen multiple articles that say that, although I don't know if there has been anything official from SpaceX.

[rockets4life97]

It seems to me this announcement is an indication that plans are moving forward for PM2. The timing has to do with the increased confidence of the successful so far DM-2 test is having on PM1 (planned Aug 30ish).

[gongora]

That is not true.

Was there never any plan to refurbish used Crew Dragon vehicles for cargo runs? I have seen multiple articles that say that, although I don't know if there has been anything official from SpaceX.

I don't know if there was ever a plan, but we've known for quite a while that they are different vehicles and would not be converted.

[Tulse]

I don't know if there was ever a plan, but we've known for quite a while that they are different vehicles and would not be converted.

What was SpaceX's intent for the refurbished Crew Dragons prior to this NASA announcement -- use them for private/commercial astronauts?

[Lars-J]

I don't know if there was ever a plan, but we've known for quite a while that they are different vehicles and would not be converted.

What was SpaceX's intent for the refurbished Crew Dragons prior to this NASA announcement -- use them for private/commercial astronauts?

Yes. But they also knew that NASA would change their mind eventually. (like they did for Cargo Dragon reuses)

[rockets4life97]

I don't know if there was ever a plan, but we've known for quite a while that they are different vehicles and would not be converted.

What was SpaceX's intent for the refurbished Crew Dragons prior to this NASA announcement -- use them for private/commercial astronauts?

Yes. But they also knew that NASA would change their mind eventually. (like they did for Cargo Dragon reuses)

It seems to me it wasn't so much "change NASA's mind" as do the paperwork and have a process approved by NASA.

[su27k]

The point I was trying to make is that SpaceX's original intent was to repurpose some Crew Dragons for cargo (since the new Cargo Dragons use the same Dragon 2 design, with the retirement of the Dragon 1). This would have allowed SpaceX to demonstrate that a Dragon 2 refurbished after being pulled out of salt water could nonetheless be safely reflown. I would have thought that NASA would have required at least one such reflight before agreeing to put crew onto a recovered Dragon.

That said, I don't know when PCM-2 is likely to take place, and I suppose SpaceX may have a few CRS missions prior in which they could demonstrate the reflight of either Endeavour or the PCM-1 Dragon.

We don't know the details of the contract, the reuse of F9 and Dragon 2 doesn't necessary have to happen in the same mission, it's possible they'll just reuse F9 for PCM-2 and add reuse of Dragon 2 in a later PCM. There's a private mission after PCM-2 which they can use to demonstrate reuse of Dragon 2 is safe.

[Asteroza]

kinda a bummer the reuse was decided after forcing SpaceX to choose that one shot valve system for the SuperDraco fix, since now they actually have to tear out that segment to replace the burst disc system...

[John Santos]

kinda a bummer the reuse was decided after forcing SpaceX to choose that one shot valve system for the SuperDraco fix, since now they actually have to tear out that segment to replace the burst disc system...

I think they only need to replace the burst disks if they actually fire the SuperDracos, which they wouldn't do on a nominal flight.  I think the disks burst when the SDs are fired, not when the LAS is activated.  Otherwise, the Dragon would be sitting there attached to the ISS with (mostly) full tanks and burst disks for up to six months, in the course of a normal crew rotation mission.

[king1999]

The timing of the Dragon reuse announcement doesn't make much sense to me, as SpaceX hasn't even returned a single crewed Dragon yet, much less demonstrated their reusability. Why now? Obviously NASA wanted to extend the DM-2 mission, but surely they could have bargained something else with SpaceX.

 (Allowing previously-flown Falcon 9s makes sense, as their reliability is well-demonstrated.)

That's not an announcement and just extracted by somebody from a contract modification signed on May 15, 2020.

[guckyfan]

That's not an announcement and just extracted by somebody from a contract modification signed on May 15, 2020.

Do you think a contract modification is less than an announcement?

[king1999]

That's not an announcement and just extracted by somebody from a contract modification signed on May 15, 2020.

Do you think a contract modification is less than an announcement?

I was just saying that was not an announcement.

[Mandella]

kinda a bummer the reuse was decided after forcing SpaceX to choose that one shot valve system for the SuperDraco fix, since now they actually have to tear out that segment to replace the burst disc system...

I think they only need to replace the burst disks if they actually fire the SuperDracos, which they wouldn't do on a nominal flight.  I think the disks burst when the SDs are fired, not when the LAS is activated.  Otherwise, the Dragon would be sitting there attached to the ISS with (mostly) full tanks and burst disks for up to six months, in the course of a normal crew rotation mission.

But doesn't that mean that they can't test the SuperDracos between missions without replacing the disks?

[Vettedrmr]

But doesn't that mean that they can't test the SuperDracos between missions without replacing the disks?

Correct.

[Doesitfloat]

But doesn't that mean that they can't test the SuperDracos between missions without replacing the disks?

Correct.

I don't see what the issue is. They test them on he initial build, then replace the disks.  The refurbishment cycle  may be almost identical to the initial build cycle.