SpaceX Falcon 9/Dragon COTS Demo (C2+) GENERAL DISCUSSION

[Jorge]

I think this one will be fully disassembled to check for problems and then reassembled for display. I doubt they will start reusing them before flight 6 or 8.

Once they have elsewhere to go you me.  NASA won't allow a used dragon to go to the ISS again.,

No, once again, this is wrong.  NASA never said anything about used Dragons going to ISS.  NASA said to price the CRS contract assuming new Dragons for each mission because the feasibility and cost are unknown.

So do you think SpaceX will eventual be able to renegotiate their CRS contract to be able to reuse the Dragon capsules?

Why would it need to be renegotiated?

Really gotta wonder how carefully you read what Jim wrote there.

[Joffan]

Looking round the SpaceX threads, I couldn't see whether anyone had talked about the unberth NOT requiring the station arm, and how that could be implemented.

The departure of the Dragon from the ISS was very smooth and I would imagine that the capsule could easily have backed away from the port without the aid of the arm. Will NASA/SpaceX be trying departure without arm assistance on any future visits?

No, CBM wasn't designed for it. Unbolting mechanism assumes the module with the PCBM (Dragon in this case) is secured by the arm.

Thanks, I was wondering about that. So I guess the follow-on question is: how much does the arm have to assist? Could it just back the capsule off by say 1m, without turning it? It seems we spent about an hour in arm ops that could perhaps be saved on future missions.

[Jorge]

Looking round the SpaceX threads, I couldn't see whether anyone had talked about the unberth NOT requiring the station arm, and how that could be implemented.

The departure of the Dragon from the ISS was very smooth and I would imagine that the capsule could easily have backed away from the port without the aid of the arm. Will NASA/SpaceX be trying departure without arm assistance on any future visits?

No, CBM wasn't designed for it. Unbolting mechanism assumes the module with the PCBM (Dragon in this case) is secured by the arm.

Thanks, I was wondering about that. So I guess the follow-on question is: how much does the arm have to assist? Could it just back the capsule off by say 1m, without turning it? It seems we spent about an hour in arm ops that could perhaps be saved on future missions.

No, absolutely not. The arm needs to turn Dragon so that its LIDARs are pointing back at the ISS so that Dragon can measure range and range rate during departure, and it needs to back Dragon far enough away for positive clearance during the turn.

[happyflower]

I think this one will be fully disassembled to check for problems and then reassembled for display. I doubt they will start reusing them before flight 6 or 8.

Once they have elsewhere to go you me.  NASA won't allow a used dragon to go to the ISS again.,

No, once again, this is wrong.  NASA never said anything about used Dragons going to ISS.  NASA said to price the CRS contract assuming new Dragons for each mission because the feasibility and cost are unknown.

So do you think SpaceX will eventual be able to renegotiate their CRS contract to be able to reuse the Dragon capsules?

Why would it need to be renegotiated?

Really gotta wonder how carefully you read what Jim wrote there.

One moment there. I think I understand his question, but you guys are sticking on a point of discussion.

Responding to Jim or Jorge from the OP:

Since its not specifically forbidden in the CRS contract, what if after 5 flights or so (pick a number), once the processing flow to reuse a Dragon (feasibility and costs, etc…) are better understood. Will NASA allow a re-used Dragon to approach the ISS? At anytime will that even be possible?

I don’t want to speak for someone else, but there it is. I mean I’d like to know that as well (if knowable that is)

[aero]

I interpreted Jim's various posts to say that NASA contracted for delivery of 12 payloads, and a specified total tonnage. They based their contract price on the estimated cost of 12 new Dragons delivering said payloads. NASA based their price on the cost of new Dragons and not reused Dragons because NASA knows how to estimate the cost of new Dragons. NASA does not know how to estimate the cost of used Dragons because there is no data to support such an estimate.

Based on that and only IMO, if SpaceX develops the capability to refurbish and reuse Dragons, then NASA may have the option to require further testing of the safety of said used Dragons operating within the forbidden zone around the ISS. Other ISS partners may have a say as well, I don't know. I do know that a used vehicle is not the same as a new vehicle.

edit: Or perhaps more operational experience with used vehicles, rather than dedicated testing.

[sweb]

Hi

just a quick one
why is the grapple fixture on the capsule  and not on the trunk located

[happyflower]

I interpreted Jim's various posts to say that NASA contracted for delivery of 12 payloads, and a specified total tonnage. They based their contract price on the estimated cost of 12 new Dragons delivering said payloads. NASA based their price on the cost of new Dragons and not reused Dragons because NASA knows how to estimate the cost of new Dragons. NASA does not know how to estimate the cost of used Dragons because there is no data to support such an estimate.

Based on that and only IMO, if SpaceX develops the capability to refurbish and reuse Dragons, then NASA may have the option to require further testing of the safety of said used Dragons operating within the forbidden zone around the ISS. Other ISS partners may have a say as well, I don't know. I do know that a used vehicle is not the same as a new vehicle.

edit: Or perhaps more operational experience with used vehicles, rather than dedicated testing.

I dont think the first part of your statement will preclude a used Dragon going to ISS on a CRS flight. NASA has already paid for the flights up, so replacing a used Dragon for a new one will not have additional costs to NASA since SpaceX will have to eat that cost.

But I think you have a good point that as a used vehicle it may have other/additional qualifications to do before its allowed to approach the ISS. So that may add too much cost to SpaceX and it maybe just better(cheaper) to go with a new capsule.

Anyway this is all theoretical for me, since I think all the CRS flight Dragons will be used for SpaceX research or donated to a museum.

[jjknap]

Can someone tell me what the large, pronounced "crack" is on the Dragon that is seen in the landing photos?  You can actually see it in the orbitting photos as well, but it is easier to see upon landing.  Does it have anything to do with the parachute system?

[modemeagle]

Can someone tell me what the large, pronounced "crack" is on the Dragon that is seen in the landing photos?  You can actually see it in the orbitting photos as well, but it is easier to see upon landing.  Does it have anything to do with the parachute system?

[Jim]

Hi

just a quick one
why is the grapple fixture on the capsule  and not on the trunk located

so it can be reused

[Prober]

I interpreted Jim's various posts to say that NASA contracted for delivery of 12 payloads, and a specified total tonnage. They based their contract price on the estimated cost of 12 new Dragons delivering said payloads. NASA based their price on the cost of new Dragons and not reused Dragons because NASA knows how to estimate the cost of new Dragons. NASA does not know how to estimate the cost of used Dragons because there is no data to support such an estimate.

Based on that and only IMO, if SpaceX develops the capability to refurbish and reuse Dragons, then NASA may have the option to require further testing of the safety of said used Dragons operating within the forbidden zone around the ISS. Other ISS partners may have a say as well, I don't know. I do know that a used vehicle is not the same as a new vehicle.

edit: Or perhaps more operational experience with used vehicles, rather than dedicated testing.

I dont think the first part of your statement will preclude a used Dragon going to ISS on a CRS flight. NASA has already paid for the flights up, so replacing a used Dragon for a new one will not have additional costs to NASA since SpaceX will have to eat that cost.

But I think you have a good point that as a used vehicle it may have other/additional qualifications to do before its allowed to approach the ISS. So that may add too much cost to SpaceX and it maybe just better(cheaper) to go with a new capsule.

Anyway this is all theoretical for me, since I think all the CRS flight Dragons will be used for SpaceX research or donated to a museum.

Since Dragon is a new design, and SpaceX continues to "tinker" with the design, a new Dragon each time might be a given.

[Space Pete]

Hi

just a quick one
why is the grapple fixture on the capsule  and not on the trunk located

so it can be reused

Also, so that aerodynamic forces don't rip it off during launch.

[joek]

I interpreted Jim's various posts to say that NASA contracted for delivery of 12 payloads, and a specified total tonnage. They based their contract price on the estimated cost of 12 new Dragons delivering said payloads. NASA based their price on the cost of new Dragons and not reused Dragons because NASA knows how to estimate the cost of new Dragons. NASA does not know how to estimate the cost of used Dragons because there is no data to support such an estimate.

Based on that and only IMO, if SpaceX develops the capability to refurbish and reuse Dragons, then NASA may have the option to require further testing of the safety of said used Dragons operating within the forbidden zone around the ISS. Other ISS partners may have a say as well, I don't know. I do know that a used vehicle is not the same as a new vehicle.

edit: Or perhaps more operational experience with used vehicles, rather than dedicated testing.

I dont think the first part of your statement will preclude a used Dragon going to ISS on a CRS flight. NASA has already paid for the flights up, so replacing a used Dragon for a new one will not have additional costs to NASA since SpaceX will have to eat that cost.

But I think you have a good point that as a used vehicle it may have other/additional qualifications to do before its allowed to approach the ISS. So that may add too much cost to SpaceX and it maybe just better(cheaper) to go with a new capsule.

Anyway this is all theoretical for me, since I think all the CRS flight Dragons will be used for SpaceX research or donated to a museum.

Aero got it about right.  A nit: NASA just wanted delivery of X over period Y at a firm fixed price of $Z; SpaceX did their estimating and provided a proposal.  Apparently, since SpaceX could not accurately estimate costs for refurb's, NASA asked them to provide pricing based on new.*  However it happened, it was  prudent risk mitigation, as it would have been in no one's interest to have SpaceX go broke or have to renegotiate a higher price (and NASA more budget) because SpaceX flubbed their cost estimates.

Also note that the CRS contract doesn't specify a launch vehicle or spacecraft, much less**  whether the spacecraft is new or used.  In any case, there are other reasons why SpaceX and NASA might find refurb advantageous: potentially more profitable for SpaceX and lower cost to NASA.  Maybe not significant factors today, but CRS provides for competing task orders and on-ramping new providers. Today CRS may effectively be limited to SpaceX and OSC, but from a contract perspective it's competitive and the field is open.

** Edit: Oops, sorry, it does...

IV.A.1 MINIMUM REQUIREMENTS COMPLIANCE
... Specifically, SpaceX will rely upon its Falcon 9 launch vehicle and Dragon spacecraft, both of which are manufactured by SpaceX at facilities in the United States and use minimal foreign components or technologies in a manner consistent with U.S. laws and regulations.

*  Exactly who asked who for what and when is unclear.  IIRC that was mentioned once in passing by someone from SpaceX long ago at a press conference (something to the effect of "NASA asked us...", unfortunately can't find a reference).

[mr. mark]

CRS looks to be on fast track with NASA after SpaceX COTS 2....
http://www.spaceflightnow.com/falcon9/003/120602crs/

[Avron]

CRS sounds like its a few weeks away, but does no-one find it strange the Dragon has no markings.. I have just finished looking a maybe a zillion hi-res images in L2 and no markings??

[mr. mark]

Why does Dragon need any markings? There's no other commercial vehicle flying.   

[Avron]

Why does Dragon need any markings? There's no other commercial vehicle flying.   

This side up...?

[go4mars]

My very technical question:

At 49-54 seconds, what is the flame from the upper stuff...

[Kabloona]

CBS 60 Minutes ran their previous SpaceX piece again tonight, with extra footage of the COTS2+ mission tacked onto the end.

Still touching to see Elon get choked up when asked about the opposition to commercial space from his boyhood astronaut heroes...wonder if the success of COTS2+ has softened any opinions there.

[Prober]

Apologies if this has been covered already.  I haven't yet worked my way through all of the SpaceX threads (uncharacteristcally I know).  Actually just watched the launch for the first time just now.  Believe be when I say I'm swamped!

My very technical question:

At 49-54 seconds, what is the flame from the upper stuff...

wb go4mars,  I have a better question.    Can LOX be used to pressurize?    Past times the valves are closed prior to launch and LOX is not seen out of the valve.