space news from Aug 31, 1992 AW&ST

Henry Spencer summaries


[Aviation Week & Space Technology subscription address is 1221 Ave. of the Americas, New York NY 10020 USA. Rates depend on whether you're "qualified" or not, which basically means whether you look at the ads for cruise missiles out of curiosity, or out of genuine commercial or military interest. Best write for a "qualification card" and try to get the cheap rate. US rate circa $80 qualified, higher for unqualified. It's weekly, it's thicker than Time or Newsweek, and most of it has nothing to do with space, so consider whether the price is worth it to you.]

NASP project office says it needs $150-175M in 1993 just to keep the program going, and if less than $150M is available, the program should simply be terminated.

Mars Observer launch slips due to contamination of the spacecraft, possibly from a dry-nitrogen feed system used while the Cape was being battened down for Hurricane Andrew. MO to be removed from its Titan for cleaning; with luck it can still make its launch window. [It did.]

Endeavour rolls out for Spacelab-J mission.

Preliminary report on the tethered-satellite fiasco: last-minute structural reinforcements were botched, leaving a projecting bolt in a position to interfere with tether hardware. Projected results match the 256m jam exactly, and examination of the actual hardware shows abrasions in the right places.

Aug 22 Atlas-Centaur comsat launch fails, once again a Centaur ignition failure. GD is not happy. Planned launches of a Navy comsat (on A-C) and a classified something (on Titan-Centaur) are on hold pending investigation. GD has asked Lt. Gen. Forrest McCartney, former KSC director, to chair an independent oversight panel to monitor the investigation. Initial indication is that both RL10s ignited but one failed to reach full thrust, setting the Centaur tumbling.

NASA looks at a small fast mission to Pluto, putting a pair of 200kg spacecraft on a pair of Titan-Centaurs (or, failing that, on a pair of Protons!) with multiple solid upper stages, launching into a direct trajectory without a Jupiter assist (giving a shorter flight and more flexibility on launch date). JPL's baseline is $400M for both craft, not including launches. These are pretty small spacecraft, and doing good outer-planet missions at this weight is a bit of a challenge. (The reason for having two of them is that Pluto's slow rotation makes it impossible for a single fast flyby to image the whole planet... so two flybys half a rotation period apart are needed.) A science working group recommended a lightweight imaging system, a mapping infrared spectrometer to get some idea of surface composition, and a look at the atmosphere using either an ultraviolet spectrometer or a radio occultation experiment (with the twist that the spacecraft would be the receiver, rather than the transmitter as has been usual in the past). The mission baseline specifies about 7kg of instruments using about 6 watts of power, with instrument choice stressing operational maturity rather than new technology. Even this limited mission would greatly improve knowledge of Pluto (and its moon Charon). The proposal is for a new start in FY94 and launches in 1998-9.

A Russian film-return remote-sensing satellite is in orbit, carrying a US DoD experiment! Both the USAF and USN are involved; the experiment is a sample collector investigating the formation of beryllium 7 by cosmic rays striking Earth's atmosphere. More such experiments are planned, to exploit the quick-turnaround launch opportunities that the Russians offer. The same satellite will also release a pair of precision-made spheres, to be tracked by ground radar in an investigation of atmospheric density variations; the Russians have invited the US to do this as a formal joint project, although political obstacles in the US may limit it to informal cooperation this time.

Russia recovers its experimental scramjet launched last November, and confirms that it achieved supersonic combustion. Immediate recovery was not possible because of bad weather after the test, although the impact point was known well enough that it was found promptly when conditions finally permitted a search.

Big story on NASA's FLO -- First Lunar Outpost -- proposal for a return to the Moon before 2000 AD. Griffin says one should not be surprised if it looks fairly familiar: "we already know how to go to the Moon". It looks like a somewhat scaled-up Apollo in many ways. The big surprise is abandonment of lunar-orbit rendezvous; this hurts payload by forcing the lunar lander to carry the full return vehicle, but improves flexibility because the surface crew can leave without waiting for a rendezvous window... a wait that can be lengthy at higher latitudes. FLO also rejects Earth-orbit assembly, to avoid requirements for multiple simultaneous launch preparations, on-orbit cryogenic-fuel storage, and limited launch windows. Each FLO mission would use two launches. The first would send a surface habitat, including consumables, on a one-way unmanned mission to a site checked out by an unmanned lander; the habitat would deploy solar panels etc. automatically, and would be fully checked out by remote control before the manned launch. The manned launch would carry a four-man crew in a return capsule looking like an enlarged Apollo, capable of returning the crew and 200kg of cargo to a land landing. Both launches would use a common oxyhydrogen lander vehicle, powered by four RL10s modified for throttling. The return stage would probably use storable fuels. The first mission would have the crew on the Moon for 45 days, doing a detailed investigation of the geology of an area about 50km across. An advanced spacesuit would be needed, as would an unpressurized rover substantially scaled up from the Apollo one. The first FLO mission would carry about 3 tons of instruments, including a small test system for making bricks and extracting oxygen from lunar soil.

The launch vehicle for FLO needs to have about 1.5 times the payload of a Saturn V. Marshall is looking at two concepts. One *is* basically a modernized Saturn V, with five F-1As in the first stage plus a pair of two-F-1A strap-on boosters, and J-2Ss in the upper stages. [The exact details of the engines are not explained, but they are presumably souped-up derivatives of the F-1 and J-2 used in the Saturn V.] The other is a derivative of the Nonexistent, er excuse me National Launch System, with hydrogen first and second stages and four two-F-1A strapons. Lewis is talking about a nuclear translunar stage with two 50klb nuclear engines; this would cost more than chemical but would develop technology important for later expansion to Mars missions.

NASA does not want to put a price tag on missions that are still rather sketchy, but Griffin says he can't do a credible lunar program on less than a few billion a year.

FLO's unmanned precursors are having tough sledding, however, because Congress is being very tight with money. NASA had hoped to do detailed design on a lunar geochemical mapper next year, build it in 1994 and launch it in 1995, preferably with a stereo/gravity mapper following a year later. The amounts of money involved are really quite small, but Congress is still balking, to the point where Griffin was not surprised that the mapper missions didn't get funded. His office will concentrate on adding some more detail to FLO and doing a similar design sketch for Mars, to look at the awkward question of how much common hardware should be used. (It's awkward because a long-term commitment to a Mars mission is so uncertain that spending more to develop common hardware is not obviously a good move.)


MS-DOS is the OS/360 of the 1980s. | Henry Spencer @ U of Toronto Zoology -Hal W. Hardenbergh (1985)| henry@zoo.toronto.edu utzoo!henry