SpaceX COTS Demo 2 Updates

[docmordrid]

The latter - I doubt the Orbcomm's have the fuel to take them to 775km once dtopped from the trunk

I see it as a variation on this

SpaceFlight Services planner guide....

[ugordan]

I also doubt the Orbcomm's have the fuel to take them to 775km once dtopped from the trunk

Based on published info, they will/would barely have any prop left after circularizing that 775 km altitude.

[go4mars]

I also doubt the Orbcomm's have the fuel to take them to 775km once dtopped from the trunk

Based on published info, they will/would barely have any prop left after circularizing that 775 km altitude.

and then uses the remaining performance margin to boost itself + Orbcomms (attached to the 2nd stage as already illustrated)

Can the 2nd stage do some of that orbcomm circularizing work too?

[Chris Bergin]

So does Nov 30th look solid enough to ask for the day off? 

Nope. Nothing is set yet and AV is simply quoting from the STS-135 presser. Nothing was set in that either.

The presser just a few days before noted it might be 2012.

I'd guess December, providing NASA and SpaceX have smooth future meetings, because, as noted by Suff, they are still discussing F9 Flight 2 and other things.

[cuddihy]

I also doubt the Orbcomm's have the fuel to take them to 775km once dtopped from the trunk

Based on published info, they will/would barely have any prop left after circularizing that 775 km altitude.

and then uses the remaining performance margin to boost itself + Orbcomms (attached to the 2nd stage as already illustrated)

Maybe the 2nd stage does some of that work too.

It'd be a lot chancier than using the Dracos for obvious reasons.

[Jorge]

Ok, it looks like the plan is for Spacex to go for a combined mission with a November 30th launch and a December 7th berthing date (hopefully a date that will not live in infamy for Spacex)

Already out of date. 12/9 berthing now.

[Antares]

It just leaves his statements logically incomplete.  He doesn't "have to" say anything, but he he states that they are still in the process of approving the combined flights, without defining the focus of that process.  It makes it sound like NASA is fumbling around and just indecisive.  This isn't to say that NASA is fumbling, just that Suffredini's statements lack a narative of how they will get to approval or disapproval.

If you're in the middle of business negotiations, why would you tilt your hand in public?

[ugordan]

Can the 2nd stage do some of that orbcomm circularizing work too?

Without the "delta-V" mission kit, no. And let me stop you right there: no, I don't think there's even the slightest possibility the 2nd stage will have Draco RCS on this flight.

[Halidon]

Potentially stupid question: Assuming the demo flight Dragon berths safely, is there anything standing in the way of the ISS crew packing in some downmass for the trip back?

[mr. mark]

this off the twitter line from Jeff Foust...

Bill Gerstenmaier: NASA technically agreed w/SpaceX to combine C2/C3 flights, but still working some details before formally approving it.

[Jason1701]

Potentially stupid question: Assuming the demo flight Dragon berths safely, is there anything standing in the way of the ISS crew packing in some downmass for the trip back?

The ISS crew would pack in all they can fit. However, it would likely be trash or low-value return items until Dragon reenters a few more times.

[SpacemanInSPACE]

Can anyone explain the reasoning behind the Nov. 30 launch date that has been thrown around alot? Why then?

[mr. mark]

It has been thrown around for a while now that a combined mission would happen at the end of this year or beginning of 2012. Mainly because of the extra testing needed to accomplish the mission objectives.

[RocketEconomist327]

Can anyone explain the reasoning behind the Nov. 30 launch date that has been thrown around alot? Why then?

The reason we do not know the date is because NASA needs to validate SpaceX data.  Once that data is validated NASA will decide when to launch.  Remember, this is a demo mission that may carry provisions to ISS. 

Therefore, ISS must be ready to receive those provisions and there must also be a slot available for Dragon to berth to.

This is how it was explained to me.

VR
RE327

[Ben the Space Brit]

Bill Gerstenmaier: NASA technically agreed w/SpaceX to combine C2/C3 flights, but still working some details before formally approving it.

Is that like Charlie Bolden technically agreeing to the SLS design but OMB working some details before formally approving it? My point is that 'working some details' can cover a multitude of evils.

[AnalogMan]

For those interested in what Bill Gerstenmair had to say about D2/D3 during the STS-135 post-landing presser yesterday (July 21), here's my transcript:

Jay Barbree:
"Bill, the question today really is: We're celebrating, but when will astronauts lift off again from Cape Canaveral?  We've had a 166 flights, with this one, and I know that SpaceX is asking to deliver cargo before the year's end with their Dragon spacecraft.  They haven't yet got approval from NASA - maybe you could tell us where that is?  And if you really think they have a shot, or Boeing has a shot with their CST-100, to put astronauts in space from here by 2014 or 2015 - what's your thinking on that?"

Bill Gerstenmair:
"First of all in terms of the combination of the C2, which is the demonstration flight where we're just going to go close to space station with the Dragon capsule, and then we were going to do C3, which is actual go up and stop and then be picked up by the arm and then berthed to station.

We technically have agreed with SpaceX that that we want to combine those flights, but we haven't given them formal approval yet.  We still want to go through some more analysis, to go take a look and define exactly what criterion makes up that combined mission, what objectives are there, what the go/no go criteria is, and there's also some details of the flight design we would like to get through.

And then there's also some analysis we'd like to work with SpaceX in terms of their software systems, do some Monte-Carlo runs to go look at the robustness, 'cause overall what we want to do is we want to get to cargo delivery as fast as we can.  And if the systems are mature enough and the design is mature enough combining those two flights - is that [the] best way to to get cargo to ISS in the fastest manner possible?  If there's still a little bit of work to do and there's a lot of work to do you may gain something by splitting them back into two missions.  Where you do one you do a little bit less demanding, but then that gives you a lot of knowledge that then helps you apply that knowledge to that next mission that follows.

So we're trying to decide what the right exact step is but we're doing all the planning to go ahead have those missions combined - the capsule's been designed that way, the software's been built that way and we're just kind of waiting for the right formal time that we collectively agree that this is the right thing to go forward.  So we're very aggressively working that with the SpaceX Corporation through a series of reviews and also some internal reviews within NASA to get that activity done, and there may not be a [CRS?? unintelligible] day we kinda talked about deciding that in July - it may be in August, September we'll find the right time when we get enough runs and data behind us so we can formally say we're heading that way but we are technically definitely looking at those missions being combined.

The next question is a little bit about commercial crew [...]"

[Norm38]

SpaceX is mucking up the COTS testing process by flying secondary payloads. If the secondary payloads are an issue, they get them off this flight. Those secondary payloads only make the flight software more difficult to develop and test anyway.

Fly the Orbcomm satelites on their own launcher. Give the commerical community some confidence that you still remember how to launch their payloads. Perhaps a successful commerical launch might even bring in some additional business.

In the meanwhile, trying to fly secondary payloads on the COTS missions is delaying the flights, and delaying the start of the CRS contract. All of these schedule delays mean delayed payments from NASA. Getting the last of the COTS milestone payments and starting the CRS payments earlier should help cover any additional costs of launching these secondary payloads on a separate launcher.

Sorry but I don't agree.  First, the Dragon is volume limited on cargo, not mass limited.  So unless NASA loads up the trunk, every Dragon cargo launch will have mass to spare for secondary payloads.  If there's a posibility of them being on every ISS flight, better that NASA learns how to deal with them up front.

Second, do you honestly think the Orbcomm launch budget can afford a dedicated launch?  No, they have to ride piggyback.  That is demonstrating a sucessful, low cost, commercial launch market for microsats.

And third, carrying secondary payloads whenever possible gives SpaceX that much more revenue for development.  If SpaceX delays the schedule a bit and gets paid later, that's their problem.  But if NASA were to ban secondary payloads from an ISS flight, then NASA should have to pay more to cover that lost revenue.


P.S.

When it comes to security, you have to demonstrate that it doesn't (pose a danger).

But when it comes to engineering, trying to prove a negative is one of the biggest wastes of time and money there is.  I can cycle something 10,000 times and it doesn't PROVE one bit that it'll still work on cycle 10,001.  As long as the second stage and the Orbcomms never intersect ISS's orbit, that should be good enough.

[Jim]

  As long as the second stage and the Orbcomms never intersect ISS's orbit, that should be good enough.

That is the issue, it can

[Robotbeat]

  As long as the second stage and the Orbcomms never intersect ISS's orbit, that should be good enough.

That is the issue, it can

Can this be mitigated if Dragon does a couple of burns before getting to ISS's orbit? In other words, if the second stage puts it in enough of a different orbit initially (one which doesn't intersect ISS's orbit) then Dragon moves to the correct orbit on its own?

[Jim]

yes