[Hmm, I seem to be a bit behind. The next few summaries may be a bit terser than usual, to save time.]
[Aviation Week & Space Technology subscription address is 1221 Ave. of the Americas, New York NY 10020 USA. Subscriber service (800)525-5003, International (609)426-7070. 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 is $82 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.]
William Pickering, whose involvement with spaceflight included working on the first US satellite and being head of JPL in the 60s, receives the first Francois-Xavier Bagnoud Aerospace Prize.
ESA contract for the Artemis experimental data-relay satellite goes to Alenia. Launch circa 1996.
Grumman gives pink slips to all 854 staff working on the station engineering and integration contract, effective 30 Nov. NASA would like to keep a few dozen of them, but Congress said no.
Interesting coincidence: the $400M that the US will pay Russia for use of Mir in the next four years matches Russian estimates of the financial loss from the cancelled hydrogen-engine contract with India.
It's Been A Bad Autumn Dept: Landsat 6 is missing and feared dead. The launch, on a refurbished Titan II, went fine: L6 was put into a transfer orbit with an apogee of 391.08nmi (390.95 planned) at an inclination of 98.01deg (98.006 planned). "The orbit at which we injected the satellite-upper stage combination looks like it was absolutely perfect." Payload separation looked normal... after which L6 vanished. It was supposed to fire its apogee motor about 14min later; presumably it didn't, and reentered unobserved. Early reports that it had been tracked were wrong: the trackers saw ERS-1, which is in a similar orbit.
Eosat and NOAA are unhappy. Landsats 4 and 5 are still in orbit, but are old and not in great shape -- their design life was three years, and they were launched in 1982 and 1984 resp. Landsat 7 exists only as long-lead bits and pieces, and on a normal schedule would not be available for 4-5 years. The loss is especially painful because L6 had an enhanced Thematic Mapper, with a 15m-resolution panchromatic band that would be a bit more competitive with Spot than the 30m resolution of the older TM.
Martin Marietta is also unhappy. It supplied both launcher and satellite for this one. MM has appointed an internal review team, in addition to the group that is looking at company-wide quality control. MM says there appears to be no common element in the losses of Mars Observer, NOAA-13, and Landsat 6. The gloom is mitigated only a little by the success of ACTS and the L6 Titan II (fourth of 14 ex-ICBMs modified as launchers; there are several dozen more old ICBMs in storage, currently being shifted from the closing Norton AFB to an Army storage depot near Pueblo, Colo.).
Speaking of failures... The USAF still hopes to get one of its patiently-waiting Titan-IV-Centaurs off the Cape this year. One of the SRBs is being destacked to replace a segment that underwent fuel repairs; it is now deemed suspect under new rules. Some consideration is being given to replacing two segments in the SRBs of the other T-IV-C.
MM is in final negotations to buy GD's Systems Systems Division, builders of Atlas and Centaur. Talks have been underway for some time, but have been delayed repeatedly when launch failures changed the economic picture of the two companies enough to invalidate some of the earlier work. GD has been looking for a buyer for SSD for over a year, as it unloads what it sees as peripheral divisions. SSD's future health will depend a great deal on whether Atlas 2AS, whose development has absorbed a lot of cash, flies well in December. GD hasn't signed a new launch contract in a while, and it really has to get its act together on both reliability and launch rate if it is to recover from its recent failures; if it does, it's in good shape. Right now, things are strained, and SSD has tightened up, with both layoffs and a reduction of management layers. GD considered simply closing SSD, but there were too many contractual commitments to customers.
There is a possibility that Loral may try to bid for GD-SSD. Its chairman is acquisition-hungry and has outbid MM on several other things in recent years.
An unusual bipartisan coalition of congressional staffers is pushing for a new government-developed medium launcher, criticizing existing US launchers as complex, fragile, and more concerned with performance than with reliability and costs. "In the US, we build launchers that are like race cars, but what we really need are trucks." Of interest is a comparison of manpower and times:
Crew Size Days on Pad Ariane 4 about 100 10 Delta 2 300 23 Atlas-Centaur 300 55 Titan IV >1000 100 Staff Kourou Space Center 900 Cape (except NASA) 11000 KSC 18000
[Personal opinion: the staffers have identified the key problems, all right... The trouble is that their answer is an old-technology launcher built by a massive consortium of contractors supervised by a massive consortium of government agencies. This is a recipe for pork, not for horsepower. The idea that free enterprise might produce something better through competition appears never to have entered their heads.]
Columbia crew prepares for Spacelab Life Sciences 2 mission. Payload includes 48 rats; late in the mission, Martin Fettman (who is, by the way, a vet) will decapitate and dissect five of the rats so that changes in their systems can be studied without the disturbances introduced by reentry and landing. Other studies will follow up the SLS-1 work, which among other things upset a number of earlier assumptions about short-term human reactions to free fall. Fettman and Shannon Lucid will wear heart catheters on ascent. After landing, the crew will be flown to JSC lying down, to minimize immediate readaptation effects. The mission will last 14 days, and assorted engineering tests will include use by the pilots of a portable-computer-based shuttle landing simulation, meant to give long-duration crews refresher training before descent.
Congress is getting tired of the unsettled space-station plans, especially given recent political turmoil in Russia. Congress in fact is generally tired of business-as-usual at NASA and wants to see some changes. The latest example is that the House has completely lost patience with ASRM: on 6 Oct, they voted 305-123 not to even consider the NASA appropriations bill until ASRM is deleted from it.
ICAO to establish special task force aimed at getting navsat systems into widespread use in aviation ASAP. The last time this sort of thing was done was in the late 1950s, when a special task force was put together to sort out the problems of introducing jet airliners. ICAO feels that the technical issues are solved but the institutional ones -- notably, who owns, controls, and operates the satellites -- are not.
Inmarsat braces itself for competition in the mobile-communications business, most notably from Iridium and its lookalikes. Inmarsat is seeing major growth in its aviation business, but expects that nautical and land-mobile users will remain the backbone of its business for now, because while the aviation market is bigger, the higher costs will slow its development.
Major story on DC-X, which has now flown three times. The next step would be DC-X2 [aka several other names], which would be larger and would demonstrate the lightweight structure that is the one major omission from DC-X. BMDO is interested in a reusable sounding rocket, carrying a ton or payload to 100nmi, but would like to make study awards to at least two contractors with differing approaches.
AW&ST traces the history of recent SSTO work to a 1982 Boeing proposal, which became part of the classified Science Dawn program, to build a sled-launched HTHL SSTO. Other contractors joined, and about 1986 it was renamed Science Realm. At this point, it started to become clear that the requirement for horizontal takeoff was "warping the design". "Rockets have good thrust-to-weight ratio and you might as well use it for vertical takeoff." As NASP began to build up steam for its air-breathing work, Science Realm became Have Region "to throw the rocket guys a bone". Have Region built prototype lightweight structures with 1970s materials -- mostly mildly-exotic metals -- to see if it was possible to fly something soon. The Have Region structures worked and were within 3% of the specified weights, so the basic answer was "yes", but some problems had been encountered, and it looked like some of the simpler materials being studied by NASP -- notably graphite-epoxy composites and aluminum-lithium alloys -- would be better. In 1989, as Have Region wound down, SDIO funded a small study on using these alternate materials (but not the more exotic ones NASP was developing from scratch) in an SSTO, and the current program grew out of that.
DC-X, within its limitations, appears to have been a complete success. In particular, it has demonstrated cheap refurbishment by a small team of a reusable rocket... albeit at a much smaller scale than the shuttle.
P&W is also happy about the performance of DC-X's RL10A-5. It's basically a standard RL10 with the nozzle shortened, but some other small changes were needed too. The chamber was stretched slightly, because the pumps are powered by chamber and nozzle heat and the shortened nozzle would have reduced the available heat too much. Also added, to meet the need for throttling to 30% of full thrust, was a throttling valve that controls bypassing of hot gas around the pump turbine. Production RL10s actually already have such a bypass valve, used to trim the chamber pressure, and the -5 just needed one with more authority. P&W thinks they could get thrust down to 20-25%, but at 15-20% it has instability and overheating problems. Even at 30%, things run warmer due to reduced flow rates: the turbine gas is at +50F instead of the usual -100F.
Aerojet teams with Lyulka to improve, market, and build Lyulka's D-57 oxyhydrogen rocket engine, a 90klb-vacuum-thrust engine using staged combustion at 1600psia chamber pressure. The engine is 1960s-vintage, and is "a little heavy", but otherwise is most interesting because there is no other hydrogen engine in that size range. In particular, it's perfect for an SSTO demonstrator, where the RL10 is a bit small.
The D-57 was built as a hydrogen replacement for the kerosene upper-stage engines of the N1 lunar booster. With the standard 143:1 nozzle, vacuum Isp is 456 at a 5.8 mixture ratio. Use at sea level would require either a two-position nozzle or some way of inducing symmetrical flow separation in a high-expansion nozzle. A two-position nozzle was tested, although its low-expansion position was still a bit long for sea-level use. Four unused D-57s still exist, plus two used ones (one with the two-position nozzle) and an assortment of spare parts. The production tooling appears to have been misplaced and is being sought.
Pressures in the D-57 are about half those of the SSME and materials are not exotic. One minor oddity is that the chamber is LOX-cooled; the hydrogen cools only the nozzle. The engine is throttlable to 10%. It has accumulated 53000s of run time.
Brief story on Aerojet's gaseous H2/O2 RCS for DC-X. [The story doesn't mention that it hasn't yet been used in flight!] Aerojet says GH2/GO2 is a logical choice for an LH2/LO2 vehicle's RCS: gas storage is bulky and maintaining constant flow to the thrusters can be tricky, but having fewer propellant types and nontoxic propellants is a win, and the gas tanks can be recharged from the main fuel tanks via pumps and flash boilers (DC-X, for simplicity, doesn't do that).
USAF considers adapting its Cobra Ball aircraft, which carry infrared telescopes for tracking ballistic-missile tests at a distance, to detection of tactical missile launches. Also being discussed is putting a shrunken version of the Cobra Ball sensors on existing sensor platforms like the E-3 radar aircraft.
Warfare within the Pentagon over air-launched anti-tactical-missile weapons... The USAF has proposed putting SDIO's LEAP lightweight interceptor on top of an SRAM air-launched missile, providing a relatively long-range (150+ mi) interceptor that could do ascent-phase interception and could be deployed overseas as quickly as an aircraft could fly. BMDO would prefer to develop its own Peregrine missile, a longer-term project. Critics of the USAF concept say that the SRAMs are old and the USAF has already complained about their aging rocket motors when trying to get funding for a replacement, and that USAF aircraft would need expensive new sensors to use SRAM/LEAP in combat. Supporters observe that SRAM/LEAP, unlike any other US tactical-missile interceptor except the limited-effectiveness Patriot, could be fielded within a few years and provide practical defences while follow-on systems are being developed.
The critics have also announced the discovery of a new class of threat which SRAM/LEAP could not counter: "small clustered munitions", which would deploy during ascent, and could carry chemical/biological weapons or radioactive isotopes. There is no evidence that anyone is even working on the idea right now, and opinions vary on how difficult the technology is -- it depends a lot on whether you want the submunitions to disperse at altitudes too low for near-term interceptors to reach you. Patriot and its relatives would be pretty useless against such a system. On paper, Peregrine could reach the carrier rocket at lower altitudes than SRAM/LEAP, but the technology for doing that isn't by any means an off-the-shelf item.
Belief is no substitute | Henry Spencer @ U of Toronto Zoology for arithmetic. | henry@zoo.toronto.edu utzoo!henry