henry@utzoo.uucp (Henry Spencer) (12/13/88)
[Terminology: although I know "Buran" is the name of one of the Soviet orbiters, not their whole shuttle system, the lack of a convenient, well-known name for the system inclines me to continue using "Buran" in a generic sense.] SDI launched a highly classified "Queen Match" experiment on a sounding rocket in Alaska in August to observe Soviet missiles from space. SDI will not confirm whether it worked. NASA Office of Spaceflight will renew efforts to get NASA HQ and the new Administration to support Shuttle-C development. First Titan 4 launch, originally set for October, slips up to five months due to uncertainty about structural strength of its payload fairing. There is suspicion that the Sept. Titan upper-stage failure may have been the result of the payload fairing striking the upper stage during separation. Analysis of stresses in fairing fittings has raised some doubts, so the fairing has been removed and sent back to McDonnell Douglas for modifications. The payload for the first launch is said to be a Clarke-orbit early-warning satellite on an IUS. The Atlantis STS-27 payload is a low-altitude reconnaissance satellite with deploying arms which span up to 150 ft. It has "characteristics of an imaging radar or optical reconnaissance package involving digital imaging, or both". It fills essentially the entire payload bay. Once separated from the shuttle, two long arms unfold; they carry sensors, solar panels, and antennas. Atlantis will monitor deployment and initial operation. If there is trouble, there is the option of blowing the arms off and retrieving the core for later re-use; it is thought to cost up to $500M. [In all these summaries, life is simpler if I report the stuff as if it's current news rather than past history. I do trim out or shorten obsolete items.] Buran prepared for second launch attempt. [Which worked.] The Soviets say problems in retraction of a swing arm aborted the first, but the long delay preceding a second attempt has raised speculation that that may not have been the only problem. Timing of the first launch attempt is speculated to have been chosen to allow the Mir crew to watch. Soviets say Buran is designed for up to four weeks in orbit, versus one for the US shuttle, but did not say whether this was free-flying or attached to a space station. The second orbiter, Ptichka, is in one of the processing facilities at Baikonur. NASA starts small new research program in the interaction between vehicle control and structures. A.A. Galeev elected to direct IKI, replacing Roald Sagdeev. Galeev is well thought of in the West; he was formerly chief of the Plasma Division. Soviets officially write off Phobos 1. It has probably stabilized in a gravity-gradient attitude with its solar panels pointed away from the Sun. It went out of control when a ground software-checking computer failed during preparation of a command sequence, and a technician transmitted the sequence without waiting for checking. Avtex Fibers shuts down US rayon production; this is of serious import for US spaceflight, because the stuff is used in carbon-phenolic composite materials found in a wide variety of rocket systems, including shuttle SRBs (nozzle reinforcement wrapping) and various missiles. Existing stocks will suffice for the near future, but... Contractor selection for the advanced SRB will occur early next year. Two teams are competing for it, Lockheed/Aerojet and Hercules/Atlantic. Russell Bardos, NASA shuttle-propulsion director, says that Morton Thiokol's improved SRB designs are not alternatives and will not be substituted for the ASRM. NASA will buy one more major batch of M-T SRBs, in an order to be placed in the next few months, which will carry the program through the transition period to the ASRM. France's TDF-1 direct-broadcast satellite is moving towards its final orbital position, after successful opening of its solar arrays. (This is noteworthy because the nearly-identical German TVSat 1 was written off after one solar array failed to open.) France is still looking for customers for some of TDF-1's capacity, although at least one channel will probably be leased to Germany to help cover for the loss of TVSat 1. Doubts have been expressed in the past about France's ability to find enough users to justify TDF-1 and TDF-2 (scheduled for launch late next year); France has a growing cable-TV system that will compete with them, and other lower-cost DBS projects like Luxembourg's Astra will also be a factor. A very interesting letter from Name Withheld By Request, observing that the satellite insurance industry faces three quite fundamental problems: - The steady demand for more and more performance per pound steadily boosts complexity and erodes safety margins. 20 years ago, a Delta-class satellite had only 170W of power available; today it has ten times that, at the cost of an intricate set of mission-critical mechanical devices for solar-array deployment. - Competitive pressures have steadily eroded development and testing phases of programs. "Where at one time we had a structural model, a solar/thermal model, an engineering model and a prototype before distinct flight models, we now, even with the first of a new generation, often leap from a combined structural/thermal model direct to a proto-flight, and derivatives are proven only by similarity." The insurance companies have shown no signs of objecting to this, either. - The proliferation of small-production-run specialized satellites. He suggests that reliability must be engineered into a product, rather than relying on fallible quality-control and inspection processes, and says that a major step towards this would be to get insurers involved in proposal evaluation and contract negotiation, so that unsophisticated buyers are made aware of the risks in pushing the state of the art too hard. -- SunOSish, adj: requiring | Henry Spencer at U of Toronto Zoology 32-bit bug numbers. | uunet!attcan!utzoo!henry henry@zoo.toronto.edu