Commercial Crew - Discussion Thread 1

[mkent]

One provider was new and only had a few ratings.  I don't trust new ones.

Hmmm...

I'm with Jim here.

For my business, I spend more on proven, typically more expensive tech to mitigate risks to my business. However I do cycle in less expensive and/or newer, less-proven tech from time to time for potential future efficiencies. But never exclusively. It's a process. It's a balance. The next couple of years will bring more clarity.

Exactly.  Mitigating risks is exactly what is in play here.

http://forum.nasaspaceflight.com/index.php?topic=35728.msg1265759#msg1265759

NASA's in a bind.  CCtCap is not an X-program.  They need commercial crew service in late 2017.  If that doesn't happen, they need to know by mid-2015 so they can begin negotiations with the Russians for extending Soyuz service.  Having the commercial crew contractor(s) unpredictably late risks the whole ISS.

So if NASA has only enough funds for one provider, it's got to be the low-risk provider.  That's Boeing.

If there enough funds for a second provider, they need to go with the low-cost provider (this needs to eventually be a purely commercial service for NASA to be able to afford their long-term plans).  That's SpaceX.

If there are enough funds for a third provider, it can be a high-risk / high-payoff provider.  That's Sierra Nevada (and others, but Sierra was more highly ranked in earlier competitions).

If you look at the downselections through the entire Commercial Crew process, NASA has pretty much followed this philosophy.  That's why Boeing, SpaceX, and Sierra Nevada were the final three, and why Boeing and SpaceX are the final two.  It's why the CCtCap contract provides guarranteed flights (to shorten the time table and thus reduce risk) and why if there end up being multiple providers at the end there will be a competition for additional flights.

Overall, excellent project management by NASA.  If only their other manned spaceflight programs were that well run.

[Nindalf]

And from the articles, it sounds like maybe their design upgrades were not as well developed and the schedule was not as clearly defined with reliability as many people here seem to think.

Come on, now.  The articles are extremely one-sided.  Someone leaked this to specific people, with expectations of the kind of story that would be written, either because they knew their allegiances well enough to predict the bias, or because there was an agreement in exchange for the leak.

If the intent had been simply to share the truth, the whole document would be out on the internet.  Instead, we get this, "Trust us, it says Boeing is awesome and the other guys suck.  No you can't look for yourself."

We should treat any leak articles like an unofficial press release for whoever's favored in them, until the whole document's out.

[Nindalf]

So if NASA has only enough funds for one provider, it's got to be the low-risk provider.  That's Boeing.

No, the low-risk provider is SpaceX.  The cozy familiar choice is Boeing, but that's little reason to expect them to deliver on time.  SpaceX has a vehicle operating now.  They're doing the abort tests of the crew version over the next couple of months.  They're obviously far out in front in everything but NASA paperwork.

If it's such an incredibly overwhelming priority to get an American crew launch option, they can stick some seats and suits in a cargo Dragon and launch in December.  It would be less risk than the average astronaut has accepted, historically, and probably wouldn't even double the risk of astronauts heading to spend months in their shirtsleeves in an aging space station.

So why isn't this option on the table?  Usual standards are to limit spending to under $10 million in taxpayer dollars to save one American life.  If delivering crew to the ISS is so important to American interests, they can let the astronauts bear some risk rather than spend years and billions of dollars on a chance of having a theoretically ideal system (which could still have very poor reliability in practice, since they're rushing to put people in them with a minimum of testing -- you only get something as trustworthy as Soyuz by exceeding a hundred flights of real experience, not by bureaucrats shuffling together impossible standards with launch fever and drawing a hand out of that deck).

If they need to launch in 2017, they can hope for Dragon V2 and fall back on cargo Dragon.  They can count on the bird in the hand, they can't count on some new vehicle being built to the highest standards ever applied to a crew vehicle within the next few years, no matter who's doing it.

They should be investing in the development of something meaningful in the long term, not throwing dump trucks of money at an ugly quick fix, because they do already have an ugly quick fix ready to go.  If they're going to fund multiple launch options, each should have compelling value.  None is a safer bet than Dragon V2.

[Jim]

It isn't long duration life support. I.E. it could be as simple as a CO2 scrubber. Didn't Apollo 13 rig up a setup using some ducktape and plastic bags and pieces from the LM and CM?

No, they made an adapter so that a CM LIOH canister could be used with the LM environmental control system.  The rest of the system still had to operate

[Robotbeat]

When did Dragon 2 become risky? It's an upgrade to an existing capsule

An upgrade that changes it from a cargo container into a human habitat with intricate life support systems. Though I was a DC fan, I do have to acknowledge that neither SNC nor SpaceX has ever flown humans into space before.

Dragon is part of a human habitat when docked to station and certainly has to maintain a comfortable, even temperature (as well as air circulation) and pressure. Much more than just a box.

[QuantumG]

Boeing has more experience flying humans because [whole bunch of stuff in the 60s and other stuff that isn't relevant] and ISS modules. SpaceX has no experience flying humans because they've only flown ISS modules they actually built themselves and that go through ascent and that can manoeuvre under their own power in space. <- Totally reasonable and well thought out argument.

[ncb1397]

It isn't long duration life support. I.E. it could be as simple as a CO2 scrubber. Didn't Apollo 13 rig up a setup using some ducktape and plastic bags and pieces from the LM and CM?

No, they made an adapter so that a CM LIOH canister could be used with the LM environmental control system.  The rest of the system still had to operate

Pretty sure that is exactly what I said. Anyways, we aren't talking about lunar circumnavigation duration. Nothing here needs to be overcomplicated or more complicated than manned submersibles. Oxygen candles/oxygen masks are the backup. Anyways, about 19 cubic feet of oxygen at STP is consumed by 4 astronauts in 6 hours. Dragon v1 is 350 cubic feet or pressurized volume. Elon Musk's manned dragon setup of giving an astronaut an oxygen mask in v1 was actually more than what was required. In fact, absolutely nothing at all was required.

[the_other_Doug]

Speaking of the environmental control system (ECS), it's good to learn from history.  What seems like a very simple thing (oxygen and perhaps nitrogen bottles, some plumbing, regulators and fans, a lithium hydroxide canister system and a dehumidifier) don't seem all that complicated.

But the Mercury system, built by by a company named AiResearch which had made oxygen and cabin pressurization systems for a number of aircraft, had to be reworked many times before it was cleared for flight.  For Gemini, the engineers figured it would be easy -- just put in two proven Mercury systems, one on each side of the spacecraft to support the individual pilots.  They would switch back and forth between the right and left systems for maintaining the cabin atmosphere, and each system was individually capable of sustaining the one astronaut for which it was responsible.  But, to their surprise, it didn't work.  A combined system was needed to fit in the available space and to provide acceptable life support.  And it had to be modified even before Gemini flew to support EVA, something the planners originally thought they wouldn't have to worry about until the second half of the program.

Then when we got to Apollo, we had a bunch of experience on how to do it, right?  But the ECS for spacecraft 012 had to be removed and replaced so many times (the last being in December of 1966, IIRC) that the scuffing, pushing on wire bundles and stressing the piping it caused was considered to be at least partly to blame for the condition that capsule was in at the time the fire occurred.  Heck, the fatal plugs-out test was held up for a while because there was a smell of sour milk in the suit circuit when Grissom's crew plugged into it, and they had to leave the hatch open while a few lines were flushed and then reactivated.

And heck, the Shuttle was designed to use a complex CO2 scrubbing system similar to the one used by the Russians on Mir and in the ISS SM.  If my aging and drug-addled memory (from the painkillers after my difficult surgeries this year, just to be clear for the NSA monitors, LOL) is recalling correctly, I believe it involved a water circuit that was used to absorb CO2 and excess cabin humidity from the cabin air.  That system had enough glitches that, for most missions, it was pulled out and an Apollo-style LiOH canister system was installed in its place.

So, just looking at that very basic kind of system, just because it's been done before doesn't make it easy to do again.  Elegant, economic and lightweight systems are hard to come by -- it's often not even pick any two, sometimes it's pick any one.

I'm confident that SpaceX will be able to design and install the needed systems, but it's not a given that it will be easy.  Learning from history, some of them may require some redesign along the way and become real pacing items for a 2017 launch.  And as with most things, the items that will rear up and bite them in the butt aren't necessarily on their (or our) radar at the moment.

-Doug

With my shield, not yet upon it

[A_M_Swallow]

If items require frequent rework then they need testing at least a year before launch.  So that is 2015 or 2016.  I hope there is a milestone where the ECLSS is ground tested by locking people into an air tight box for several days.

[docmordrid]

>
I'm confident that SpaceX will be able to design and install the needed systems, but it's not a given that it will be easy.  Learning from history, some of them may require some redesign along the way and become real pacing items for a 2017 launch.  And as with most things, the items that will rear up and bite them in the butt aren't necessarily on their (or our) radar at the moment.

-Doug

SpaceX is using an ECLSS made by Paragon SDC, and developed during COTS-1 for commercial spacecraft. IIRC they're also providing systems for Orion.

[sublimemarsupial]

>
I'm confident that SpaceX will be able to design and install the needed systems, but it's not a given that it will be easy.  Learning from history, some of them may require some redesign along the way and become real pacing items for a 2017 launch.  And as with most things, the items that will rear up and bite them in the butt aren't necessarily on their (or our) radar at the moment.

-Doug

SpaceX is using an ECLSS made by Paragon SDC, and developed during COTS-1 for commercial spacecraft. IIRC they're also providing systems for Orion.

Nope, SpaceX ECLSS for both the current Cargo Dragon and Dragon 2 are in house. Paragon was dropped a while ago.

[docmordrid]

Really?

Edit: based on this hire?

https://www.linkedin.com/jobs2/view/9527411

[baldusi]

Btw, is not oxygen but CO2 poisoning one of the problems. The other being humidity control (with water extraction being, of course, the hard one).

[yg1968]

When did Dragon 2 become risky? It's an upgrade to an existing capsule

An upgrade that changes it from a cargo container into a human habitat with intricate life support systems. Though I was a DC fan, I do have to acknowledge that neither SNC nor SpaceX has ever flown humans into space before.

It isn't long duration life support. I.E. it could be as simple as a CO2 scrubber. Didn't Apollo 13 rig up a setup using some ducktape and plastic bags and pieces from the LM and CM? Dragon v1 is already a human occupied spacecraft when attached to ISS. If the life support system doesn't work, and in an emergency, dragon can land pretty much anywhere land or sea. This is making a mountain out of a mole hill.

While any speculation of this being the issue or not is nearly meaningless... I did want to point out that it is not that trivial to uprate a vehicle.  Yes, a CO2 scrubber is a relatively simple thing.   Now you have to dehumidify and keep the temperature in a narrower band.  Means a more active cooling system.  Since you have humans you need more oxygen tanks and a way to fit/feed that into a spacesuit.  Those computers that were fine with redundancy for unmanned cargo now need to be MUCH more robust.  Your automated piloting system must now have a way for a pilot to fly manually.  Your comm systems needs more redundancy on the ground.  And so on and so on.  Each item in itself is not a deal breaker but it combines to add up to significant modifications.    SpaceX is definitely ahead of the game in having to be modifying a flying vehicle but it is significant work.  And from the articles, it sounds like maybe their design upgrades were not as well developed and the schedule was not as clearly defined with reliability as many people here seem to think.

You make some good points. But nevertheless, the CST-100 is only a mockup at this point as you pointed out and SpaceX has a capsule that has already been tested. So they are ahead in terms or real hardware. They have had a few years to plan out the life support issue.

[Jim]

You make some good points. But nevertheless, the CST-100 is only a mockup at this point as you pointed out and SpaceX has a capsule that has already been tested. So they are ahead in terms or real hardware. They have had a few years to plan out the life support issue.

To me, this is more than a mockup.

[woods170]

You make some good points. But nevertheless, the CST-100 is only a mockup at this point as you pointed out and SpaceX has a capsule that has already been tested. So they are ahead in terms or real hardware. They have had a few years to plan out the life support issue.

To me, this is more than a mockup.

Correct. Too bad Boeing didn't use that for their parachute drop tests.

[SWGlassPit]

Correct. Too bad Boeing didn't use that for their parachute drop tests.

What more would be learned from that that wasn't learned from using a boilerplate capsule?

You don't waste expensive hardware on potentially destructive tests unless you absolutely have to.

[arachnitect]

You make some good points. But nevertheless, the CST-100 is only a mockup at this point as you pointed out and SpaceX has a capsule that has already been tested. So they are ahead in terms or real hardware. They have had a few years to plan out the life support issue.

To me, this is more than a mockup.

Correct. Too bad Boeing didn't use that for their parachute drop tests.

Wasn't the spacex drop test vehicle a modified v1?

[woods170]

Correct. Too bad Boeing didn't use that for their parachute drop tests.

What more would be learned from that that wasn't learned from using a boilerplate capsule?

You don't waste expensive hardware on potentially destructive tests unless you absolutely have to.

Tell that to SpaceX. They based their parachute drop test article around an actual pressure hull and dropped it from a helo. Twice.
Somehow that didn't bother them.

On the other hand you have Jim who became somewhat upset when QC suggested that the Boeing drop test article was constructed mainly of wood, sheet-metal and styrofoam. Big difference between a for-real pressure hull and a glorified wooden model.

[erioladastra]

It isn't long duration life support. I.E. it could be as simple as a CO2 scrubber. Didn't Apollo 13 rig up a setup using some ducktape and plastic bags and pieces from the LM and CM?

No, they made an adapter so that a CM LIOH canister could be used with the LM environmental control system.  The rest of the system still had to operate

Pretty sure that is exactly what I said. Anyways, we aren't talking about lunar circumnavigation duration. Nothing here needs to be overcomplicated or more complicated than manned submersibles. Oxygen candles/oxygen masks are the backup. Anyways, about 19 cubic feet of oxygen at STP is consumed by 4 astronauts in 6 hours. Dragon v1 is 350 cubic feet or pressurized volume. Elon Musk's manned dragon setup of giving an astronaut an oxygen mask in v1 was actually more than what was required. In fact, absolutely nothing at all was required.

Another example of way over simplfying things.  NASA requirements are for ~80 hours of free flight capability.  Also, NASA has said 3 days on masks is not acceptable.  You may quiblle with that but if you are to meet the requirements it is not that simple.