henry@zoo.toronto.edu (Henry Spencer) (12/10/90)
The cover story on this one is the X-30 design selection. It's a slim lifting body with very small delta wings far aft, a pair of vertical tails, and a cockpit blister (with side-facing windows) near the nose. Exact size not yet set, expected to be 150-200ft long and 250-300klbs takeoff weight. The X-30's wing is mostly there as a mounting for control surfaces. The body size needed to provide inlet and exhaust aerodynamics for the scramjets at high speed turned out to provide ample lift by itself. Exact control-surface layout is still being settled, as are the details of the engines. There will be a small rocket engine, 50-70klbs thrust, for the final push into orbit, in-orbit maneuvering, and retrofire, and also as a reserve propulsion system for safety during testing. Early flights will not have a go-around capability on landing, but this is just to go easy on the large, fragile aircraft early on; later it will be possible. [At one point there was a faction saying that go-arounds were unnecessary and the X-30 should be planned around shuttle-style no-room-for-error landings, but that idiotic idea seems to have died quietly, probably about one minute after the pilots heard about it.] Lots of X-30 coverage, much of it not very interesting. X-30 flight-test planning is starting, particularly insofar as it affects the aircraft design. One big issue is windows: the pilots, after some limited-visibility tests at Dryden, badly want at least some direct view. Hence the side windows. Forward view is still being debated: the engineers like television-based systems, but the pilots are concerned about reliability and time lag, and want to see something like a retracting periscope instead. Escape systems are also uncertain; the current leading notion is to follow the SR-71 and use high-performance ejection seats plus spacesuits. Mir hatch-repair spacewalk set for Oct 19 postponed; Strekalov has a cold. Picture of Boeing's concept of a "lunar utility vehicle", essentially the Apollo rover upgraded for longer life, on-site maintenance, and modern technology. Atlantis clears its fueling test. NTSB hands down recommendations concerning three near-misses between NASA astronaut T-38s and airliners. The astronauts are told to pay closer attention to instructions and to write them down, the controllers are told to be more on the ball, and NASA is urged to upgrade the 1960s-vintage radios and other electronics of its trainers. NASA says it is working on the electronics upgrades already. Antarctic ozone hole re-opens, worse than ever. Satellite images. NASA talks about ideas being worked on for shuttle upgrades. Prominent among them is a nine-screen "glass cockpit" closer to modern airliner cockpit technology than the rather dated equipment the orbiters now have. Another notion is using complex castings and plasma-spray technology to build SSMEs with many fewer welds, significant because the welds are tricky and hard to inspect; the SSME will probably get a bit heavier in the process, although its performance may increase slightly to match. The Hardware Interface Module which connects the launch processing system to the ground-support equipment will be redesigned and replaced, cutting costs because the current HIM design uses obsolete components that are increasingly difficult to get. Several other ideas, farther away, are also being looked at. Replacing the hydrazine-burning APUs in the SRBs with a solid-motor-gas-generator design would eliminate one messy and hazardous subsystem. Newer materials in the orbiter's fuel cells could improve power output and extend life. Modernizing the whole orbiter electrical system might be worthwhile. And tests are being done to study using a lidar system to measure high- altitude winds more quickly and more accurately than current systems, giving better weather prediction for launches and reentries. Picture of Rockwell's mockup of the cryogenic pallet, to be carried in the orbiter cargo bay to extend fuel-cell power supply up to 16 days on Columbia and Endeavour. The first extended-duration flight is set for March 1992, by Columbia. Other changes needed include regenerative carbon-dioxide removal, a better waste collector system, more nitrogen tanks, and "crew cabin improvements". Rockwell is funding the cryogenic- pallet development temporarily, and will be reimbursed by NASA over the next three years. [Surprisingly brave of them, actually.] Soviet space program currently faces uncertain prospects due to political and economic upheaval. A new space policy is needed. The future of Glavkosmos in particular is uncertain: it was meant as the point of contact for commercial space activity, but now the individual "companies" are authorized to negotiate and sign their own deals. The Intercosmos program, providing low-cost flights for socialist nations, is also in doubt, since the Soviet Union is going to be less willing to provide free rides in future. Its customers are also skeptical; Romania, for example, says it benefited little from its 1981 cosmonaut flight, and is much more interested in joining ESA. The German space program is also facing some uncertainty due to the recent reunification and the coming financial strains of modernizing East Germany. One firm decision, though, is that the separate East and West German imaging instruments being built for the Soviet 1994 Mars mission will be combined. Soviets are modernizing their manned maneuvering unit for improved thrust (needed for handling heavy components), better telemetry, and a remote- control capability allowing the MMU to be controlled from Mir in an emergency, e.g. incapacitated cosmonaut. Letter from Rick Rezabek suggesting that ESA needs to step back and rethink Hermes, since the recent inclusion of an expendable "resource module" carrying several important systems indicates that Hermes is simply too small to carry out its missions. -- "The average pointer, statistically, |Henry Spencer at U of Toronto Zoology points somewhere in X." -Hugh Redelmeier| henry@zoo.toronto.edu utzoo!henry