Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: utzoo!henry From: henry@utzoo.UUCP (Henry Spencer) Newsgroups: sci.space,sci.space.shuttle Subject: Re: space news from 22 Sept AW&ST Message-ID: <7279@utzoo.UUCP> Date: Tue, 4-Nov-86 19:28:26 EST Article-I.D.: utzoo.7279 Posted: Tue Nov 4 19:28:26 1986 Date-Received: Tue, 4-Nov-86 19:28:26 EST References: <7254@utzoo.UUCP>, <346@xios.UUCP> <7275@utzoo.UUCP>, <1010@husc2.UUCP> Organization: U of Toronto Zoology Lines: 70 > How can you be sure that the chance of disastrous failure is little? > Our track record only suggests that the chance of a disaster isn't greatly > over 1 in 25, which seems to me to be unacceptable without taking precautions > to reduce it... Have you read the Rogers Commission report? The problems generally show a strong correlation -- not a perfect one, but pretty strong -- with cold temperatures and high-pressure leak tests. (The incidence of O-ring trouble jumped *spectacularly* when NASA increased leak-test pressure; the Rogers people were appalled that nobody had noticed.) Admittedly I should probably have said "little doubt" rather than "no real doubt", but it seems like a good bet to me. At the very least, given the correlations, it's safe to say that SRB reliability with warm joints and low-pressure leak tests should be rather better than the overall current record. > ... stay grounded until they are checked over by people who are not being > pushed to gloss things over... If the basis for this is that it's unacceptable to risk crews, all I can say is that qualified volunteers should not be hard to find. If the basis is excessive risk to payloads, see comments below. If the basis is risk of losing another orbiter, I *do* agree that it is not realistic to fly more Shuttle missions without a commitment to prompt replacement of orbiters lost due to accident. (You will note that the previous sentence does *not* limit itself to missions prior to the safety overhaul.) > Also, you propose getting launches going for military missions. Why > so much interest in running military missions in such haste? ... When it comes to keeping the launch crews in practice, the nature of the payload is pretty irrelevant. And I personally think that a lot of other payloads are more important. However, flying the Shuttle before the safety changes are complete must be considered slightly risky. Not risky enough not to do it, but risky enough to think twice about launching one-of-a-kind payloads like the Space Telescope. The loss of a single military payload wouldn't be a tenth of the disaster that losing the HST would be. Other reasons are that the public is more willing to accept risks on military missions flown by military crews -- look at the death rate in military flying if you doubt this -- and that the current climate in Washington is more favorable to strong backing of risky undertakings when there are military motives. (This may not be pleasant, but we have to live in the real world, folks.) > Further militarization of space is one of the things we least need. It is going to happen whether we like it or not; have you seen the current notions of what the Shuttle cargo manifest will look like when launches resume? Given that those payloads *will* fly, let them take the risks and keep the system going while its problems are fixed. > Why should the > military get priority in recovery efforts after something goes wrong? They aren't getting priority in recovery efforts, they are being asked to assume the responsibility and risks of keeping a flawed system going *before* the recovery effort is complete. They are, after all, sworn to give their lives for their country if needed. > It is criminal that, after the shuttle has been presented to the taxpayers > as a commercially viable venture, the commercial ventures and all but a > handful of scientific missions have been kicked off it... Yup. But the taxpayers, or rather their elected representatives, didn't feel like funding a commercially viable venture. The Shuttle program survived by appealing to the military for help; we are now paying the piper. (And the tune he played wasn't even all that good, dammit! Not even a fifth orbiter, much less a fifteenth.) -- Henry Spencer @ U of Toronto Zoology {allegra,ihnp4,decvax,pyramid}!utzoo!henry