Direct 3.0: NASA is in a bind.

It's not so danged obvious. Seemingly small changes can cost an immense amount. The cost just to change the outer skin of the Shuttle's external tank from aluminum to aluminum/titanium allow was over half a billion dollars.

Direct is reusing stuff that no longer exists. The logistics pipelines for the Shuttle have been terminated. A lot of the manufacturing capabilities are gone. The costs of bring those capabilities back online will be immense. Wayne Hale discussed this last August in his blog. From http://wiki.nasa.gov/cm/blog/waynehalesblog/posts/post_1219932905350.html:

Starting four years ago, the shuttle program in its various projects made "lifetime buys". That is, we bought enough piece parts to fly all the flights on the manifest plus a prudent margin of reserves. Then we started sending out termination letters. About two years ago, we terminated 95% of the vendors for parts for the external tank project, for example. Smaller, but still significant, percentages of vendors for SSME, Orbiter, and RSRB have also been terminated.

A lot of things that go into the shuttle build up are specialty items. Electronics parts that nobody makes any more (1970's vintage stuff). Hey, if it works, why invest money in certifying new parts? Certifying new ones would be even more costly! Specialty alloys to meet the extraordinary demands of space flight, parts that are made by Mom and Pop shops mostly in the LA basin are norm rather than the exception. You might think that simple things like bolts and screws, wire, filters, and gaskets could be bought off the shelf some where, but that thinking would merely prove how little you know about the shuttle. The huge majority of supplies, consumable items, maintenance items, they are all specially made with unique and stringent processes and standards.​

Direct is getting one last shot with the Augustine Committee. The Direct proponents had their say. The committee has asked the Aerospace Corporation to conduct an independent analysis of the Direct proposal.

My guess is that Direct will not win the day. It is a paper study. It has to compete with another Shuttle derivative (Shuttle-C (another paper study)), with systems already well into the development phase (Ares and COTS), and with systems that already exist (EELV).

 

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I'm all for improvements but but be fair theirs (o my eyes) little difference between the 1960 rockets and the ones to day. Rocket's have almost zero progress they have the same insane cost and the same insane mass ratio flirting with 1%.
If they have so little ambition they might as well go for the cheaper faster option.

Well when they redesigning they might as well look into adding more modern bolts and screws the design can't changes that much for using a different set of bolts

 

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The only reason it looks cheaper and faster is because it's all on paper. Every new rocket design looks cheaper and faster initially. Every new rocket design hits some major stumbling block along the way from design to first flight, and hits yet more stumbling blocks from first flight to operational flights. Direct hasn't hit these bumps in the road, and that is not because these bumps don't exist.

You are not a rocket scientist. You simply are not qualified to judge Direct. Shoot, I am a rocket scientist and I am not qualified to judge it. It takes a large team with a huge diversity of skills to assess the quality of a rocket design. Even the Augustine committee members by themselves are not qualified to give a fair and accurate judgement of the Direct design. That is one reason why they asked Aerospace Corp. to look it over.

 

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I completely agree. Rocket Science, is after all, Rocket Science.

Handwaving over the detail, and a flashy QT movie make it all sound so simple, but making a new vessel from spare parts isn't really a simple solution, or let's face it, private industry might just have thought of that, sourced parts, and done it themselves, instead of developing their own systems.

 

Indeed, take Ariane-5, they re-used the flight control software from Ariane-4, and, well, the results of that decision got spread all over the ocean near French Guiana.

 

Good example. BTW, the wikipedia article on Ariane 5 flight 501 is a bit flawed. This, for example, is just plain wrong:

Efficiency considerations had led to the disabling of the software handler (in Ada code) for this error trap, although other conversions of comparable variables in the code remained protected. This led to a cascade of problems, culminating in destruction of the entire flight.​

A seemingly simple calculation can expand to a horrendous mess in flight software. For example, an Earth-bound application that requires finding a solution to \(ax^2+bx+c=0\) will simply plug in the quadratic equation: \(x=\frac{-b \pm \sqrt{b^2-4ac}}{2a}\). One line of code. In flight software that might be dozens of lines of code. A decision as to whether to add the extra code needed to protect against the overflow, underflow, and constraint errors exceptions that might result is made at design time. The wiki article claims the software handling for the overflow error that triggered the failure was disabled. Wrong. The overflow protection softwere never existed. How can you disable something that doesn't exist? The crash of Ariane 5 flight 501 was caused by a software error, but not a programming error. The programs worked exactly as specified and designed.

This article includes material directly from the Inquiry Board's report:
http://www.cs.clemson.edu/~steve/Spiro/arianesiam.htm

And here is the Inquiry Board's report itself:
http://esamultimedia.esa.int/docs/esa-x-1819eng.pdf

 

But Direct is not a new rocket design, at least far less new about it then Ares and Ares is already over budget and NASA has not received new money even to pay for the original budget of Ares, so in the end Ares V is doom to be canceled no matter what, and we will be stuck with no moon capable rocket unless we change gears.

 

Okay I realise that but NASA's budget yust isn't cut out for mannend space flight anymore.
If there is no near magical cheap way then it would seem better to abandon it (mannend space flight) all together and focus on creating cheaper rockets/rocket planes and space elevators (don't know if that last ones is actualy possible but those nano tubes have also other usefull/profitable applications)

That or triple NASA's budget

 

NASA should just buy some Energia rockets from the Russians. They have been tested, and would be far cheaper than developing a new rocket. NASA needs a heavy lift vehicle, Russia could use the cash, it's win/win.

 

What a beautiful fallacy. According to you when a small child tells a mathematician 2+2=4 that child should shut it mouth.

 

It's win/lose. The price Russia charges the US to take an astronaut to/from the ISS will increase after the Shuttle program terminates. After this point, Roscosmos will be the only game in town.

There are other alternatives to both Ares and Direct. The Augustine committee is investigating several.

 

Considering the chairman bias in the Augustine committee he likely to favor EELV. EELV would be the cheapest option for LEO operations at this point, but it has no potential for Lunar operations and beyond.

 

That could be factored into the deal for buying Energia rockets, keep the cost in check during the period the contract for the rockets is in place?

But yeah, only having one rocket supplier is perhaps subject to 'market forces' a little too much, and the Russians aren't daft.

I just think it's a shame the Energia rockets didn't get used. All that R&D, for nothing. Same with Buran, really.

 

The Aerospace Corporation is evaluating Direct for the Augustine committee. Let's see what comes out before we start playing the conspiracy game, shall we?

 

Why you believe the committee will make a unbiased decision free from human failings?

 

The committee has done a lot to minimize such bias. It has asked for an outside evaluation of Direct to be performed by The Aerospace Corporation. The committee members come from academia, NASA, and industry, including competitors of Lockheed.

Turning the question around: What makes you believe the Direct proponents are free from human failings? Opportunities to design and develop a new launch vehicle occur very, very rarely. These guys had there say at glory and lost twice. This is their third shot. If they come out on top, good for them. If they don't, they need to accept that they lost, period.

 

I never said they were.

Or laugh "I told you so!" when Ares V is canceled and we never go back to the moon. In first run the plan was not well developed, the second time NASA had a vest interest in denouncing them because it went with Ares already, if they lose a third time I'm fine with them quiting but that does not change the serious failing of Ares.

 

Hmm...Really? I get that you can't just phone in an order for SSME turbopumps and have them delivered the next day, but are there really no off-the-shelf bolts or screws or wires out there in the wide world of construction and engineering supply companies that would be appropriate for use in a space vehicle, and that you could simply order more of as needed? I know they're "made with unique and stringent processes and standards" and all, but there are many companies that would be happy to sell you tons of screws that are machines to sub-micron tolerances, many of which were also designed to function in various extreme environments. What exactly are you looking for, screws that were hand-carved by Swiss artisans to nanometer precision?

How much effort was made to use "off-the-shelf" stuff when they were designing it? Was it a matter of drawing up specs and then just awarding contracts for crazy, unnecessarily-specific things right and left?

 

That the Shuttle uses a lot of custom parts is in part a reflection of when it was built but is also a reflection that off-the-shelf devices don't cut it in lots of applications. Google "custom fasteners" and you will see that use of specialty fasteners is the norm in many domains.

 

SpaceX may prove the need for "custom" parts wrong.