I am an engineer and do a lot of work in the vibration, fatigue and failure areas. I also know a little about various areas of the shuttle, and have several opinions about it.
a) NASA (and contract) engineers do an enormous amount of analytical analysis, followed up by test verification. Compared to private industry the amount they do is almost unbelievable, and in general I believe they do very good work, at the lower levels.
b) Per my considerable experience, most designs work out to be conservative, and I'll choose not to explain why. The shuttle in my opinion is not that old and thus 'fatigued out'. It has not experienced enough flights. Besides this is something that is entirely controllable, via inspections, analysis, etc.
c) It is impossible and improbable to design a zero error system such as a shuttle, for lots of reasons, including human error. What we are seeing with the shuttle is generation of statistical history that yields insight into future probability of failure, assuming it continues to be used.
The shuttle in my opinion was and is a monstrosity that should never have been built. It was more than likely built for all the wrong reasons - employment of a lot of highly paid professionals probably being the main one. This type of thing helps keep the masses happy, and politicians in office.
I suspect it was known well before building the shuttle that many of the goals laid out could never be met. The biggest single problem is uptime - the shuttle has to spend a huge amount of time on the ground between flights, at an enormous expense. During development this information was more than likely known and recognized, but squashed, before reaching higher budgetary authority. The show always must go on.
It would have been much cheaper to continue to use expendable boosters for launching of payloads. A reusable human shuttle probably made sense, to design at that point in time or later, and probably would have been successful. Now NASA is stuck with a maintenance nightmare, one they do not have money to feed, and one that sucks money away from new developments. They are truly in a catch 22 situation, just like the rest of the American economy.
The shuttle was a result of the exact same mentality that created the stock market bubble. This same mentality pervades American companies today. It will take a long time to root out, and a lot of pain. I just finished investigating a 'shuttle' type vibration/fatigue boondoggle, on a much smaller basis, in my current company. Just like the shuttle no one was/is directly accountable.
Listen to Prechter. He explains it fairly well.
But by GOD we Americans will keep at it, until we get it right or are totally bankrupt. |
