Sep 11 1978
From The Space Library
NASA announced it had tentatively selected five scientific experiments for its gamma ray observatory, a planned 1984 mission to explore a variety of the most energetic forms of radiation known: very high-energy gamma rays from pulsars, nuclear gamma rays, and gamma ray bursts. Observatory data should provide a much better understanding of the nature of supernovas, pulsars, quasars, radio galaxies, the character of the early universe, and the possible existence of antimatter in the universe. Scientists also hoped to learn more about incredibly dense matter composing objects such as neutron stars, matter so compressed that a teaspoonful would weigh millions of tons. Data from the GRO might also tell more about gamma-ray bursts, erratic gamma-ray pulses of unknown origin that flashed across the solar system every month or so. Although Congress had not yet approved GRO, early solicitation of scientific participants and investigations would allow for mission definition and a prompt start after approval.
GSFC would manage the observatory to be carried by the Shuttle into a planned orbit of 400 to 500km (250 to 300mi). NASA had selected principal investigators and experiments: Dr. James Kurfess of NRL, broad line gamma-ray spectrometer; Dr. Laurence Peterson of the Univ. of Calif., San Diego, narrow line gamma-ray spectrometer; Dr. Carl Fichtel of GSFC, high-energy gamma-ray detector; Dr. V. Schoenfelder of the Max-Planck Inst., Garching, W. Germany, medium-energy double Compton telescope; and Dr. Gerald Fishman of Marshall Space Flight Center, transient gamma-ray monitor. (NASA Release 78-140)
NASA announced that tests by LeRC and General Electric Co., Peebles, O., on two experimental aircraft engines might result in major reductions in noise and air pollution. Technology of both engines, known as quiet clean short-haul experimental engines (QCSEE), had been directed to future short-haul commuter-type aircraft in the 450 to 800km (300 to 500mi) range customarily used by the smaller airports. NASA intended to apply QCSEE technology also to engines in the 80,700-newton (40 0001b) thrust size used in the largest planes of the U.S. commercial passenger fleet.
The two 40 300n (20 000lb)-thrust power plants had run 8 to 12db quieter than the quietest engine (the CF6) on widebodied DC-10 and 747 civil transports, about 16db below current FAA noise-level standards and some 9db below tougher FAA requirements set for the 1980s. Reduction in noise had resulted from slowing engine-exhaust velocity by increasing the ratio of air passing through the engine fan to air passing through the core of the engine, and by other design features including use of acoustically absorbent materials.
Aeronautical engineers also reported substantial air pollution reductions for the research engines, compared with engines then flying; carbon monoxide emissions, for example, had decreased 84% in one engine and 81% in another. Unburned hydrocarbons had decreased 98% for one engine, 97% for the other. LeRC engineers attributed air pollution improvements to new designs incorporated in the combustion system and said these lower emission levels would more than meet stringent EPA standards set for 1979.
An additional bonus would be fuel savings of about 10% compared with current engines of similar size. Fuel savings had resulted from replacing normally heavy metal components (the engine cowling, frame, and fan blades) with lightweight nonmetallic composite materials of equal or greater strength; The experimental engines had internal differences, but the most visible was their location on the aircraft wing: one had been under the wing as in conventional installations, the other over the wing. Wing flaps in both positions deflected jet exhaust downward to add lift for short-run operations.
QCSEE was a $30 million program to develop and demonstrate powered-lift engines (under and over the wing) that could reduce congestion, noise, and air pollution around airports. General Electric Co. had been prime contractor for both engines. (NASA Release 78-138)
Hughes Communications Services, Inc., Culver City, Calif., had received a $335 million Navy Systems Command contract to provide 5yr of Leasat (leased satellite) communications services at each of four locations in space starting in 1982, Aerospace Daily reported. Hughes, which had proposed to use its Syncom-4 Shuttle-optimized spacecraft, had won out over Comsat General Corp. and TRW Inc. Leasat would replace the Gapfiller service currently leased from Comsat General's Marisat system, and would complement the TRW-built Navy-owned FltSatCom system by serving both Navy ships and Army, Marine Corps, and Air Force ground-mobile forces. Choice of the Hughes system, dedicated to Pentagon use, should enhance prospects of a ESA and INTELSAT joint offer of a civilian system to be used by the pre-Inmarsat joint venture. (AID, Sept 11/78, 38)
NASA had dropped supersonic transport-oriented research aircraft, previously considered as a new start for FY83, from its latest 5-yr plan covering FY 1980-1984, Av Wk reported. Inclusion of the 75 000lb-class aircraft in an earlier 5yr plan had angered Congressional foes of supersonic transport. A senior NASA official acknowledged it had been a mistake to include the aircraft in the earlier plan. (Av Wk, Sept 11/78, 13)
ESA announced it had awarded to the European consortium Cosmos headed by Messerschmitt-Bolkow-Blohm, W. Germany, a contract for phases C and D of the scientific satellite Exosat to include fabrication, integration, and testing of the observatory intended to measure position, structural aspects, and spectral and temporal characteristics of x-ray sources. It would carry four experiments: two imaging telescopes for low-energy x-rays, a large-area proportional-counter array, and a gas scintillation spectrometer for medium-energy x-rays.
The observatory, mounted on a 3-axis-stabilized platform, would travel in a highly eccentric orbit whose apogee (roughly above the North Pole) would be at 200 000km altitude. ESA planned to launch Exosat in the second quarter of 1981 on an Ariane equipped with a fourth stage to put the spacecraft into the required orbit. (ESA Release Sept 11/78)
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