Shades of foam and failed o-rings?
A fourth crack has been found on Discovery’s external tank. How this will affect Discovery’s November 30 launch remains unknown. There will a briefing on Monday to discuss the status of the schedule. This quote however gives me the willies:
External tank crack repairs are not unusual. Some 29 stringer cracks were found in 18 previous tanks, according to an official familiar with their history. Four have now been found in Discovery’s tank, ET-137, and three were found in a tank scheduled for use by the shuttle Atlantis next summer, ET-138. Doublers were used in 23 repairs.
There is a saying that we always fight the last war. After the Challenger accident NASA made great effort to prevent another o-ring failure in the solid rocket boosters, and ignored the foam falling from the external tank. After the Columbia accident, NASA then made great effort to prevent another piece of foam from hitting an orbiter.
Unfortunately, it appears that NASA may now be ignoring this crack problem. Even though they have been able to repair past cracks, for this many cracks to occur this often should cause alarm bells to ring throughout the agency, forcing a look at the problem in toto. Instead, it appears management has been making catch-as-catch-can repairs.
What makes this situation even more difficult is the factory that makes the external tanks has shut down. No new tanks are available. Thus, there are not many options for flying these last few shuttle missions except by using the already existing tanks, and repairing them as needed.
Like I said, this is beginning to give me the willies.
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Discovery’s previous 38 safe and fruitful missions can be a highly commendable capping accolade for the entire Space Shuttle Program allowing NASA to maintain its’ integrity and mend its’ credibility for future safe manned missions to the Moon(please reauthorize this mission) and eventually to Mars.
Given the tank factory and all the tooling and equipment is NASA property, and given the economy the workers likely haven’t found any new jobs — I wonder how long it would take to restart it?
It would take quite a bit to restart the tank production line, and the presumption that most of the workforce is unemployed is also a false notion. You might be able to get back half of the workforce, perhaps, but there will be gaps from the missing people that would have knowledge on how to build these things that would have a huge impact on restarting the production.
Besides, who is going to want to come back to work on building tanks like this if your job is only going to last a couple of months with near certain knowledge that you are going to be laid off again. Unless there is an order to build a half dozen new orbiters and to completely restart the Shuttle program, I just don’t see the merit to letting this zombie continue to live on. The whole problem with the Shuttle program from its inception is half-way solutions that don’t really fix the main issues at hand, and half-funded concepts where it cost a couple billion dollars to save a few thousand or a couple million dollars at the beginning.
Perhaps it is time to simply pull the plug on the Shuttle program entirely at this point. If it is a concern for safety, the time has come to simply say “we’re done”. Nothing going up on this or the next flight are things which are absolutely necessary. Convenient and useful, perhaps, but there are other means to getting the supplies and equipment up to the ISS that are going to be on these shuttle flights. There is no need to risk human life needlessly if it is a problem.
It would make me sick if the external tank exploded again taking out another seven astronauts. If that happens, it would be the end of the NASA astronaut corps, at least as we know it, and would have some profound implications on the future of a great many NASA programs.
If the Shuttle can fly safely and be assured of at least a 99% chance of completing a successful flight, I’d say they should go for it and launch, but this could be yet another disaster waiting to happen. At least make sure the engineers on the ground and the people in the trenches get a chance to say “No!” instead of leaving the decision only to upper management at NASA. The culture to ignore the engineers on the ground is what gave us the problems with Columbia and Challenger, not that the engineers were incapable of getting a vehicle to fly safely.
>…there is an order to build a half dozen new orbiters and to completely restart the Shuttle program, ..
I guess thats the real question. Shuttle was cheaper and far more capable then proposed alternatives to service ISS (theres serious concerns the ISS can’t be maintanied without something like a shutle) — and the alternatives (from Soyuz to Orion) are expeced to less, to much less, safe.
So really one obvious cost savings option for the new congress would be to keep runing the shuttles for the next 5-10 years. So the question is how big a roadblock would that be? NASA clamis thats impossible – but pushed into a corner, NASA managers admit a lot of their raised issues are grosely overstated. So how overstated is it all?