mbullock@ADS.COM (Michael E. Bullock) (09/19/90)
Concerning the seeming inability of NASA to resolve the fuel leak problems: I don't recall NASA having these problems earlier in the shuttle program (i.e., STS 1 - 25). Is this all a recent phenomena, or did they have leaks before, but the mission scrub threshold was higher so they flew anyways? Or are they now performing more leak measurements and are finding leaks than might have escaped detection before? In other words, is NASA being more careful with respect to leaks in the post-Challenger era - or is this a hardware problem unique to these missions? Henry - what do you think? Mike Bullock Advanced Decision Systems Mountain View, CA
gsh7w@astsun.astro.Virginia.EDU (Greg Hennessy) (09/19/90)
In article <VAG%#G%@ads.com> mbullock@ADS.COM (Michael E. Bullock) writes:
#I don't recall NASA having these problems earlier in the shuttle
#program (i.e., STS 1 - 25). Is this all a recent phenomena, or
#did they have leaks before, but the mission scrub threshold was
#higher so they flew anyways? Or are they now performing more
#leak measurements and are finding leaks than might have escaped
#detection before?
There is a lot of speculation about this. It is impossible to have a
leak-free shuttle (you can't have perfect seals at a few Kelvins or
so), but there are more sensors than their used to be in the past. If
Discovery shows the same type of leak as does Columiba and Atlantis
did, then that would lend credence to NASA now detecting something
that they could not detect before. However, even if all the
shuttles have always leaked by this amount, that does not mean is is
necesarily safe to launch. It does not mean that it is unsafe either.
From the heart of Marshall Space Flight Center, along with 200 other
depressed people,
--
-Greg Hennessy, University of Virginia
USPS Mail: Astronomy Department, Charlottesville, VA 22903-2475 USA
Internet: gsh7w@virginia.edu
UUCP: ...!uunet!virginia!gsh7wgary@ke4zv.UUCP (Gary Coffman) (09/19/90)
In article <VAG%#G%@ads.com> mbullock@ADS.COM (Michael E. Bullock) writes: >Concerning the seeming inability of NASA to resolve the fuel >leak problems: > >I don't recall NASA having these problems earlier in the shuttle >program (i.e., STS 1 - 25). Is this all a recent phenomena, or >did they have leaks before, but the mission scrub threshold was >higher so they flew anyways? Or are they now performing more >leak measurements and are finding leaks than might have escaped >detection before? In other words, is NASA being more careful >with respect to leaks in the post-Challenger era - or is this >a hardware problem unique to these missions? I think you've hit the nail right on the head. The shuttle fleet is getting older and stresses are beginning to show up. NASA is being more cautious than in the past. And something else; low bid contractor labor is being used now to prep and launch the shuttles. I remember reading about the massive turnover in ground crew when the changeover to contract labor was made. This may have nothing to do with the current problem and I'm sure that there are plenty of sharp, experienced, and dedicated people working for Rockwell. Still, it raises a question in my mind considering first the defective seal on the 17 inch line and then the crimped seal on the prevalve. It sounds like lack of attention to detail during assembly similar to the problems GM had at Lordstown when they sped up the line to save a buck. Gary
henry@zoo.toronto.edu (Henry Spencer) (09/19/90)
In article <VAG%#G%@ads.com> mbullock@ADS.COM (Michael E. Bullock) writes: >I don't recall NASA having these problems earlier in the shuttle >program (i.e., STS 1 - 25). Is this all a recent phenomena, or >did they have leaks before, but the mission scrub threshold was >higher so they flew anyways?... I think it's mostly a new problem. They have gotten more thorough about testing and less inclined to disregard small anomalies, but I've never heard of things being this bad before. -- TCP/IP: handling tomorrow's loads today| Henry Spencer at U of Toronto Zoology OSI: handling yesterday's loads someday| henry@zoo.toronto.edu utzoo!henry
petej@phred.UUCP (Pete Jarvis) (09/20/90)
In article <VAG%#G%@ads.com> mbullock@ADS.COM (Michael E. Bullock) writes: >I don't recall NASA having these problems earlier in the shuttle >program (i.e., STS 1 - 25). Is this all a recent phenomena, or >did they have leaks before, but the mission scrub threshold was >higher so they flew anyways? Or are they now performing more >leak measurements and are finding leaks than might have escaped >detection before? In other words, is NASA being more careful >with respect to leaks in the post-Challenger era - or is this >a hardware problem unique to these missions? > There have always been leak detection and signature tests. This seems to be a unique problem recently. Peter Jarvis - Physio-Control
dil@mace.cc.purdue.edu (Perry G Ramsey) (09/20/90)
In article <1333@ke4zv.UUCP>, gary@ke4zv.UUCP (Gary Coffman) writes: > In article <VAG%#G%@ads.com> mbullock@ADS.COM (Michael E. Bullock) writes: > And something else; low bid contractor > labor is being used now to prep and launch the shuttles. I remember > reading about the massive turnover in ground crew when the changeover > to contract labor was made. This may have nothing to do with the > current problem and I'm sure that there are plenty of sharp, experienced, > and dedicated people working for Rockwell. > > Gary Rockwell doesn't do the ground preparation at the Cape anymore. During the early 80's (84?) a shuttle processing contract was let at the Cape with an eye on lowering labor costs (i.e. cutting everyone's salary.) The contract was won by a team led by Lockheed, Grumman, USBI, and (somebody help me). By my sources, most of the people there with the original team signed on with the new contractors, but with time a whole lot got fed up with the situation and found other employment with other companies, often the one they were with originally. Rockwell won a contract at JSC under roughly the same conditions, so they do things like certain mission planning and support roles. Rockwell-Downey still does a lot of work on keeping the Shuttle flying, but turning the screws belongs to the Cape operations contractor. NASA has established by this sort of thing a two-tiered pay structure for contractor personnel. If you are in design and building, or are at least on the contract that does you get to work for regular pay. If you are making the stuff fly, you get one of these operations contracts with an eye on keeping it cheap. Do you wonder where the best people go? (statistically, of course. There are good people in operations, there just tougher to find.) Rockwell-Space Transportation Systems Division alumnus " Station " " " If you are making the stuff fly -- Perry G. Ramsey Department of Earth and Atmospheric Sciences perryr@vm.cc.purdue.edu Purdue University dil@mace.cc.purdue.edu We've looked at clouds from ten sides now, And we REALLY don't know clouds, at all.