henry@utzoo.uucp (Henry Spencer) (05/09/88)
More problems with the Hubble Telescope: the launch in late 1989 will be just before the solar cycle peaks in 1990, and there are already indications that this peak may be a record-breaker. The significance of this is that increased solar activity means increased air drag, and the telescope is big and fairly light, hence seriously affected. There has always been intent to reboost the HST occasionally, but if the pessimistic forecasts come true, reboost might be needed only a year after launch! Viable alternatives are a higher orbit (possible but with little margin for trouble during deployment) and a lengthy launch delay (which everyone would prefer to avoid). [Not all of this is from AW&ST; the detail is from Planetary Encounter, the newsletter I've mentioned in the past -- $35/12 issues, Box 98, Sewell NJ 08080.] USAF Space Division plans to reexamine cryogenic shuttle upper stages. The USAF would like a shuttle upper stage that could put 15 klbs into Clarke orbit, and this doesn't look practical without cryogenic fuels. Another company announces interest in doing things with shuttle external tanks: Global Outpost Inc of Virginia has approached NASA about using the tanks as experiment platforms, starting in the early 1990s. Unlike External Tanks Corp, GO does not plan to pressurize them as shirtsleeve environments. ET has asked the government to give it all rights to all external tanks [!], with it serving as intermediary for other customers to amortize management and operational costs over as many tanks as possible. ET promises to be real nice to other users. GO, predictably, prefers to deal direct with the government, and sees no need for a middleman. ET has asked the government to let it use the intertank area of the tanks on early shuttle flights, first to measure atmospheric density and drag in the tank's suborbital trajectory and then to experiment with using residual propellants for attitude control; it might even be possible to put paying suborbital payloads in there. Aussat is expected to pick its next satellite supplier around the end of May. Intelsat will make its choice in the fall. Dept of Transport would like to double the budget of the Office of Commercial Space Transportation, on the grounds that recent budget cuts have jeopardized proper supervision of the launch industry. DoT also foresees a growing need to get involved in private launch-site development, both within and outside [!] the US, and will be ill-prepared to "assist" such development without more funding. [For some strange reason, I cannot seem to recall any industry whose early growth was badly hampered by a lack of government regulation and interference! If OCST would stick to safety issues and only safety issues, they wouldn't be short of manpower. What, you thought that was all they did? Ho ho. :-(] Eosat restarts work on Landsat 6 after finally reaching agreement with DoC over it. Development stopped two years ago when government funding stopped; $220M has now been made available. There is no longer any hope of avoiding a data gap, as 6 will go up in mid-91 (Titan 2 from Vandenberg) but 4 and 5 won't last that long. Eosat hopes to hold the gap down to 18 months. NASA and contractors put heads together on insulation separation in SRBs and a possible problem with loose screws in SSME LOX pumps. Minor areas of debonding in the SRB insulation are not considered a disastrous problem, and it undoubtedly happens a fair bit due to stresses after SRB stacking, but recent debonding somewhat exceeds the current official limits. The big problem is that there is no longer any slack in the schedule for sorting out things like this, and the early-August date will thus slip. Eutelsat investigating a scheme using two or more small satellites in the same orbital position for direct TV broadcasting. NASA picks the telescoping-pole system as the low-altitude controlled- flight escape system for shuttle crews. [For those who don't remember, the problem is that the shuttle is too fragile for safe ditching or belly-landing, and someone just jumping out the hatch is likely to hit the wing.] Modifications and prototype fit checks on Discovery to be done this week, with a flight-qualified pole to be installed in July. Navy parachutists tested a prototype pole mounted on a C-141B; they reported that it works even better than expected. More tests will be run in June to certify the flight hardware, including parachutes, harnesses, the roller-equipped rings that fit over the pole, and the pole itself (which is about 5 m long and 8 cm in diameter). The pole was picked over tractor rockets because of lighter weight, longer life (the rockets have only a 5-year shelf life), less attention needed during orbiter processing, and greater safety (since carrying live rockets in the cabin presents significant risks). The pole is thought to be just as quick if not quicker in getting people out. [Frankly, I always thought the pole was the clear choice and the tractor rockets were obviously a dumb idea.] [Some of the detail in the above is from World Spaceflight News, same price and address as Planetary Encounter. I highly recommend both of them to people who want the details of most anything space-related.] Germany and Arianespace agree to move launch of TVSat 2 up to next year, from 1990, since TVSat 1's stuck solar array has proved unfixable. San Marco D/L atmospheric research satellite launched by Scout March 25 from the San Marco platform off Kenya. Full development on Hermes starts this month, design to be complete by the end of 1990. Two will be built, the first to start drop tests in 1996 and the second to fly the first (unmanned) mission in mid-97. The first manned mission will be April 98 using the first Hermes. Debate continues on whether the escape capsule planned for Hermes can be built within the time and money available, and whether it would be a viable escape method in a catastrophic accident, but officially it is still in the plans, if only to avoid public outcry if there was an accident and there wasn't an escape system. State commission asks Florida legislature for $500k for a feasibility study of a state-run spaceport. Commission also recommends state money for a commercial-space insurance fund. Hawaii is already pursuing the idea of a state spaceport and has picked a location (Palima Point). Virginia and Texas are also interested. Australia's Cape York is ahead of all competitors so far. Indonesia is looking at the idea, with enthusiastic support from Arianespace. Japan is scouting Pacific locations, and is reported to have offered to finance Cape York [Australia declined]. [This one is not space at all, but I can't resist.] Presidential Airways, a small airline based in Washington DC, reports a rush of charter inquiries from US presidential candidates, because its jets have "Presidential" prominently displayed on side and tail! Aerospace Forum article by two people from UCLA's Center for International and Strategic Affairs, urging that any future strategic-missile-reduction treaty provide for conversion into space launchers. This is not possible under the impending INF treaty, although the intermediate-range missiles are a bit small to make good boosters anyway. -- NASA is to spaceflight as | Henry Spencer @ U of Toronto Zoology the Post Office is to mail. | {ihnp4,decvax,uunet!mnetor}!utzoo!henry
marsh@mitre-bedford.ARPA (Ralph J. Marshall) (05/12/88)
I'm willing to look really stupid... Why don't they install explosive-powered ejection seats on the shuttle. I don't know enough about the technology, but there has to be some way for the pilot to get out of a SR-71 that should be close to useful, and require little effort on the part of the human. What's the story ?
henry@utzoo.uucp (Henry Spencer) (05/15/88)
>... Why don't they install explosive-powered >ejection seats on the shuttle... It's been thought about; in fact that's what the pilots had for the first few flights. The trouble is that ejection seats are heavy and bulky. There isn't room to provide a full crew with ejection seats. A secondary problem is that ejection seats introduce their own safety hazards, since they are dangerous explosive devices. (People who have to work around them treat them with great respect.) -- NASA is to spaceflight as | Henry Spencer @ U of Toronto Zoology the Post Office is to mail. | {ihnp4,decvax,uunet!mnetor}!utzoo!henry