Author Topic: Commercial Crew - Discussion Thread 1  (Read 640910 times)

Offline mkent

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Re: Commercial Crew (CCtCAP) - Discussion Thread
« Reply #440 on: 10/18/2014 01:24 am »
You realize the Falcon 9 + Dragon V2 stack is scheduled to fly early next year right?

No, not the full vehicle -- an engineering test article.

Offline joek

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Re: Commercial Crew (CCtCAP) - Discussion Thread
« Reply #441 on: 10/18/2014 01:39 am »
Then you should stay away from safety- or life-critical systems.  That is a very different world, where opportunities to iterate in the real world are limited, testing is not a sufficient defense, and mistakes can cause death, dismemberment and destruction.
I am calling you on this. Test is the ONLY true way you can determine unknown unknowns. A billion CDRs doesn't help you find unknown unknowns, just your known knows or perhaps known unknowns. ...
Getting OT but to clarify ...

Sorry if I was unclear.  I was not denigrating the importance of test nor did I intend to imply that testing is irrelevant, only that testing is an insufficient defense--or more properly much less of a defense in safety- and life-critical systems.  I did not state or mean to imply that NASA's or Boeing's traditional approach is the only way.

There is a balance between the two approaches (design-review-build-test-build-test vs, design-review-design-review-design-review-build-test).  However, as the risk and consequences of failure increase, so does the emphasis on verifying and validating requirements and design.  You see that tradeoff made every day in every engineering effort from household goods to automotive to aerospace to medical devices.

On a more personal level ... Try going to work every day thinking "If I make a mistake someone could die".  And if and someone dies, could I honestly say to the survivors or testify in court that I did everything in my power and used best practices to prevent that death?  Been there.  Done that.  Don't want to do it again.  Ever.*

So apologies if I react a bit harshly when someone asks "why isn't this development like the rest of IT (or whatever)?"  Maybe some can be as cold-hearted and calculating and would shrug off a bit of blood on their hands; me not so much.


* [sarcasm] May I interest you in our new radiotherapy treatment system that consigns patients to a gruesome death every once in a while?  We figured a few gruesome deaths is a small price to pay for accelerating time-to-market and bypassing all those costly and time-consuming reviews.  All for the greater good of course. [/sarcasm]

Edit/Lar: Softened. No name calling please.
« Last Edit: 10/18/2014 06:21 pm by Lar »

Offline QuantumG

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Re: Commercial Crew (CCtCAP) - Discussion Thread
« Reply #442 on: 10/18/2014 01:54 am »
In the expensive world of aeronautical research and development, the best test is extensive computer modeling before you begin building anything.

Worked great on Ares I.
Human spaceflight is basically just LARPing now.

Offline Robotbeat

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Re: Commercial Crew (CCtCAP) - Discussion Thread
« Reply #443 on: 10/18/2014 01:55 am »
Joek: I would assert, in human spaceflight systems, that at the extreme, being able to test something 10,000 times (with lessons-learned fed into the design which is then tested thousands of more times) but having the design itself opaque to analysis beats a totally, endlessly reviewed something that has never been tested.

And yeah, Soyuz is a good example. Besides the first few early flights (test flights, or at least they should have been), there have been zero fatalities. I would trust Soyuz more than Shuttle or Orion even in spite of the truly scary state of Russian aerospace quality control. Test flights are more important than design review.

...which gets to one of Boeing's genuine strengths, here, over SpaceX: Atlas V's longer launch history. That means a lot more than a new launch vehicle with endless review (like SLS) but basically no track record, flying manned on the second flight. Sure, Falcon 9 is human rated from the start, but flight history is where it really counts (assuming you human rate both launch vehicles). That said, such an advantage will fade dramatically before the end of 2017. F9 may have 50 flights by then, compared to around 75 for Atlas V.
« Last Edit: 10/18/2014 01:55 am by Robotbeat »
Chris  Whoever loves correction loves knowledge, but he who hates reproof is stupid.

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Offline QuantumG

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Re: Commercial Crew (CCtCAP) - Discussion Thread
« Reply #444 on: 10/18/2014 01:56 am »
Who said it was a cake walk?

Chris, respectfully, you have said that all Boeing had produced was some Power Points and Word documents. Though you did not use the term specific term cake walk, what you did say implied that Boeing had not done serious or scholarly work.

I'm not Chris, Robotbeat is. Again, Powerpoint and Word documents can be plenty hard. People make a career out of it. What it isn't is integrated hardware, which various people keep trying to insist Boeing has, but can't show us any evidence.
Human spaceflight is basically just LARPing now.

Offline Robotbeat

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Re: Commercial Crew (CCtCAP) - Discussion Thread
« Reply #445 on: 10/18/2014 01:57 am »
In the expensive world of aeronautical research and development, the best test is extensive computer modeling before you begin building anything.

Worked great on Ares I.
Yeah, that statement is a joke. Real world tests are vastly more valuable. Computer tests are just easier and cheaper, absolutely not better.
Chris  Whoever loves correction loves knowledge, but he who hates reproof is stupid.

To the maximum extent practicable, the Federal Government shall plan missions to accommodate the space transportation services capabilities of United States commercial providers. US law http://goo.gl/YZYNt0

Offline ncb1397

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Re: Commercial Crew (CCtCAP) - Discussion Thread
« Reply #446 on: 10/18/2014 01:59 am »
The only design review that matters is the one done by the physical world on a test article. The review phase could be just as blind as the design phase. Shuttle passed design reviews but didn't catch problems that only showed up during flight 25 and 113.
« Last Edit: 10/18/2014 02:06 am by ncb1397 »

Offline joek

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Re: Commercial Crew (CCtCAP) - Discussion Thread
« Reply #447 on: 10/18/2014 02:01 am »
I'm not Chris, Robotbeat is. Again, Powerpoint and Word documents can be plenty hard. People make a career out of it. What it isn't is integrated hardware, which various people keep trying to insist Boeing has, but can't show us any evidence.
Nor does SpaceX.

Offline yg1968

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Re: Commercial Crew (CCtCAP) - Discussion Thread
« Reply #448 on: 10/18/2014 02:02 am »
In any case, I think it is premature to say that "SpaceX is on the verge of completing its CDR".

The last SpaceX CDR milestone was scheduled for November last I checked. But even after they are completed, it takes a while for the announcement to be made. 

http://www.parabolicarc.com/2014/08/07/spacex-sets-dates-dragon-abort-tests/
« Last Edit: 10/18/2014 02:19 am by yg1968 »

Offline Robotbeat

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Re: Commercial Crew (CCtCAP) - Discussion Thread
« Reply #449 on: 10/18/2014 02:03 am »
I'm not Chris, Robotbeat is. Again, Powerpoint and Word documents can be plenty hard. People make a career out of it. What it isn't is integrated hardware, which various people keep trying to insist Boeing has, but can't show us any evidence.
Nor does SpaceX.
Yeah, the Dragon 2 unveiling showed hardware integration, certainly more than Boeing has.
Chris  Whoever loves correction loves knowledge, but he who hates reproof is stupid.

To the maximum extent practicable, the Federal Government shall plan missions to accommodate the space transportation services capabilities of United States commercial providers. US law http://goo.gl/YZYNt0

Offline joek

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Re: Commercial Crew (CCtCAP) - Discussion Thread
« Reply #450 on: 10/18/2014 02:14 am »
Yeah, the Dragon 2 unveiling showed hardware integration, certainly more than Boeing has.
It showed a spacecraft, not an integrated system.  If it showed an integrated system, presumably SpaceX would be past CDR by now.

Offline joek

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Re: Commercial Crew (CCtCAP) - Discussion Thread
« Reply #451 on: 10/18/2014 02:35 am »
Yeah, the Dragon 2 unveiling showed hardware integration, certainly more than Boeing has.
Don't play his goalpost moving game.

Who is moving goalpoasts?  Wasn't it you who said:
So, we again come back to the fact that everyone who is claiming Boeing has done more work than the other competitors has no way to prove their claims. As long as everyone agrees to this, I think we know how we should treat these claims.

So you take SpaceX's Dragon 2 unveil claims as proof that they have done "more work" as more credible than Boeing's claims?  Or what?

Offline TomH

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Re: Commercial Crew (CCtCAP) - Discussion Thread
« Reply #452 on: 10/18/2014 03:03 am »
I don't hear anyone saying computer modeling identifies and eliminates all problems. Nor do I hear anyone saying that physical testing should not be done. What computer modeling does is eliminate a lot of the problems earlier, before you've invested even bigger bucks into bending metal. Boeing designed the 787 this way. Did that mean it didn't need to go through many months of test flights? No, not at all. Nevertheless, the plane did not have catastrophic failures which required going back to the drawing board and starting over. If you run trial and error, and keep finding errors after each redesign, you're really wasting serious time and money. The entire purpose is to expose as many potential problems as possible before you start bending metal, then hopefully discover a minimum of other problems while you perform rigorous physical testing. If engineers have done a good job with their modeling, there won't be nearly as much to redesign after you start physical tests.

Offline Robotbeat

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Re: Commercial Crew (CCtCAP) - Discussion Thread
« Reply #453 on: 10/18/2014 03:14 am »
Everyone does modeling before building. Boeing isn't unique. Anyone with a copy of Solidworks can do it. The big difference is SpceX is flying a nearly identical craft right now, literally, and has done so successful 5 other times. SpaceX is able to feed that insight into Dragon2. Also, Dragon2 already has lots of metal bent. Outer mold line is done for at least one of them and two pressure vessels are done (I believe). SpaceX can feed the results of that into their first manned flight, too. SpaceX will soon do two aborts, both of which will further refine Dragon 2. That all beats the crap out of computer simulations, ESPECIALLY Dragon's reentry data (which computers have a difficult time accurately predicting, at least compared to just regular old FEA stress tests and subsonic CFD). Yeah, SpaceX is way ahead on hardware.
Chris  Whoever loves correction loves knowledge, but he who hates reproof is stupid.

To the maximum extent practicable, the Federal Government shall plan missions to accommodate the space transportation services capabilities of United States commercial providers. US law http://goo.gl/YZYNt0

Online LouScheffer

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Re: Commercial Crew (CCtCAP) - Discussion Thread
« Reply #454 on: 10/18/2014 01:10 pm »
I have a friend who worked designing cruise missiles (for a group that is now part of Boeing).  He described CDRs in rather unflattering terms.  He said they spent months of preparation organizing serious and formal responses to all possible questions, even ones where the sensible engineering answer is "That's a silly hypothetical question".  Then, he said, the entire engineering staff was on 24 hour call during the entire CDR.  Then if someone asked any question during the CDR (the real life example he used is "That part's an odd shape.  How will you paint it?"), the presenter was instructed to say "I don't have that process document with me - I'll bring it tomorrow."  Then at the next break, he'd contact the engineering staff, who would work overnight, frantically writing document AA-XXXX-1234, Specification for the Painting of Widget X.   They would present it the next day as if they had simply dug it out of the archives.

He said that neither of the main CDR goals (Is the design sound?  Is it ready for fabrication?) was advanced by the CDR.  The first had been settled long ago, by informal meetings between the relevant technical experts.   It was unthinkable that anyone would advance to a CDR with any serious technical questions unanswered.  This left the second part, is it ready for fabrication?  But if the design is OK, then how to build the parts is the domain of the company, and outside reviewers add very little.

This guy had worked before on the commercial side of the company, where the question of "does it work" was dictated by reputation and legal concerns, and the question of "is it ready for production" was determined by the folks responsible for building each part.   When he switched to the military side of the house (not by choice, his commercial product got cancelled),  he started to have to run formal CDRs.  He felt the process sucked up an enormous amount of engineering time, to very little practical benefit. 

Online obi-wan

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Re: Commercial Crew (CCtCAP) - Discussion Thread
« Reply #455 on: 10/18/2014 03:14 pm »
Having been through a lot of CDRs, both on the design teams and as a reviewer, I would absolutely reject the concept that they're not useful. In a perfect world, the CDR is where you certify that the design is complete and correct and you are ready to start cutting metal - but in reality, with concurrent engineering practices the wall between "design" and "fabrication" is largely broken down. There are long-lead components you have to start on well before CDR if you have a hope of making the launch on time. (Try calling a supplier and finding out the items you want have a 36-month delivery time!)

The other thing is that there is no such monolithic thing as "CDR". Every individual system usually has their own CDR, and in some organizations they have both "internal CDRs" and "external CDRs". There are "Mission System CDRs" and "Flight System CDRs" and "Program CDRs". It is absolutely true that the process is a major driver of personnel resources, and development can grind to a halt for months in preparation for the CDR cycle. (Although, if you really want to talk about major drain on resources, try going through the shuttle or station Payload Safety Review Panels - all four review cycles...)

There are some silly RIDs (my favorite was "The name of this program is stupid and you should change it", but that one wasn't even entered into the formal tracking system, it just gave us all a good laugh), but the worst CDRs I've ever been involved with were the ones where the organization wasn't ready, but the program schedule said this was when the CDR took place, and they held it anyway. That wastes everyone's time for a week and gives rise to the worst possible outcome, a "Delta CDR" where you spend another week doing it all over again. Bringing this back to Commercial Crew, NASA has a real fetish for meeting schedule, and I'm not surprised that Boeing met schedule because they live the classic flight culture, but I applaud SpaceX if they looked and said "We're not ready for CDR and we'll do it when we're ready." I think that's a lot more productive of everyone's time.

Offline joek

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Re: Commercial Crew (CCtCAP) - Discussion Thread
« Reply #456 on: 10/18/2014 04:43 pm »
Apparently I missed the memo that SpaceX's Integrated CDR milestone 13 was split into two milestones before July, and then split again for total of four milestonesin late July.  From NASA Extends SpaceX CCiCap Award Period Into 2015, Splits Up Company's Critical Design Review Milestone, AmericaSpace, July 30:
Quote
“NASA approved SpaceX’s request to split some content from its Integrated Critical Design Review (Milestone 13) to two, resulting in Milestone 13A and 13B,” said Kraft. “More recently, NASA approved SpaceX’s request to shift some content from Milestone 13A to two new milestones, Milestone 13C and 13D, along with commensurate funding. SpaceX has completed the newly formed Milestone 13A. Milestones 13B, 13C and 13D are planned for later this year.  None of the original milestone content was removed from the agreement, just shifted among the milestones, nor was any content added to the agreement.”
(There is an error in the article which shows milestone 13A as Dragon primary structure qualification test, which is milestone 12 and which as far as I can tell has not been completed.)

A good summary can be found at An Updated List of NASA's Commercial Crew Partner Milestones which shows:
M13A: Integrated Crew Vehicle Critical Design Review (complete)
M13B: Operations Critical Design Review
M13C: Crew Vehicle Technical Interchange Meetings
M13D: Delta Crew Vehicle Critical Design Review
« Last Edit: 10/18/2014 04:56 pm by joek »

Offline Lar

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Re: Commercial Crew (CCtCAP) - Discussion Thread
« Reply #457 on: 10/18/2014 06:29 pm »
I've been reluctant to wade into this because, as everyone knows, I have an opinion here, and a rather strong one at that, but on reading this thread I found a lot of less than excellentness... Posts calling others names. Posts warning against particular debate tactics. Posts cheering each other's post (that's what the like button is for).

I've edited a few. I removed a few. I may have shown my bias in not being evenhanded enough... take it up with Chris. But I'd like to see the excellentness level increased. And if we could all agree on a few things and/or agree to disagree without rehashing them in a stale manner, that would be great.
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Offline dkovacic

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Re: Commercial Crew (CCtCAP) - Discussion Thread
« Reply #458 on: 10/18/2014 07:58 pm »
As has been said multiple times on here, dismissing CDR as "just a powerpoint" shows a complete lack of knowledge of how engineering design works.

To dumb it down somewhat, CDR is when the blueprints get approved.  Here are just a few examples of tricky design issues that have to be tackled to ...
Wow! This is one of the best posts I have read on NSF. And I have read a lot of them.
« Last Edit: 10/18/2014 08:04 pm by dkovacic »

Offline Ronsmytheiii

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Re: Commercial Crew (CCtCAP) - Discussion Thread
« Reply #459 on: 10/18/2014 10:44 pm »
I have to wonder if the original COTS competition took place today under the CCtCAP model, whether SpaceX would have been awarded a contract to build a spacecraft at all.  The funding mechanism for CCtCAP maybe innovative, but all the award decisions have stifled any sort of innovation.

Unless you had a simple capsule and built a manned-capable spacecraft previously, a company was just not going to win. That was true for this round, and arguably it was true for CCiCAP (only a last minute "half-award" saved DC then) It is rather sad, wasn't commercial crew supposed to stimulate the commercial space market?

Sierra Nevada has built spacecraft for 50 years, they integrate defense aircraft that support our troops, they were arguably the most innovative business case with agreements with other space agencies but they lost because they werent Boeing or SpaceX. I see now why the "big guys" were excluded from COTS, they stifle any sort of innovation.
« Last Edit: 10/18/2014 10:45 pm by Ronsmytheiii »

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