Jun 16 1978
From The Space Library
Spacecraft controllers had completed a maneuver to move the planet-arrival point of Pioneer Venus 1 from the southern hemisphere to an orbital-injection point 216mi above the northern hemisphere, DFRC X-Press reported. The course change also had slowed the spacecraft so that it could use the sun's gravity to increase its speed. NASA expected that the flight-path change would allow Pioneer Venus 1 to enter its planned long-oval orbit tilted 75° to the planet's equator, with the closest approach 180mi from Venus, greatest distance 41 000mi. Pioneer Venus 1 had been scheduled to reach Venus in Dec. (DFRC X-Press, June 16/78, 4; ARC Astrogram, June 1/78, 1)
For 4yr, the LaRC Space Systems Div. and Flight Dynamics and Control Div. had analyzed the Space Shuttle orbiter's entry guidance and control system at the request of JSC, the Langley Researcher reported.
The system had been designed to control the orbiter from deorbit until landing, regulating both the aerodynamic surfaces and a reaction control system (RCS) composed of small rocket thrusters such as those on Apollo spacecraft, so that orbiter control had turned out to be a hybrid between aircraft and spacecraft control. Onboard computers could direct the entire orbiter entry without pilot input, or a pilot could take over control if necessary.
A primary tool in the LaRC analysis had been a reentry flight dynamics simulator (RFDS) that permitted evaluation of the onboard control system in both the automatic and the manual modes. It had also aided in developing alternate control systems to be used by the pilot if the main control system could not handle a situation. The simulator cockpit, though not an exact representation of the orbiter cockpit, did contain all the instruments and controls necessary to simulate flight: cathode-ray tubes (CRTs) showed displays identical to those on board, changing guidance information automatically as the orbiter entered various flight regimes. Push buttons and toggle switches would permit the pilot to take over any of the control functions.
LaRC investigators had found that the system was dangerously sensitive to possible sensed angle-of-attack errors in the automatic mode at hypersonic speed. Shuttle astronaut Col. Henry Hartsfield had been unable to maintain vehicle control in the manual mode. This and other problems had led to major system redesign that had been tested at LaRC and found to solve the sensed angle-of-attack problem. Investigators had then begun work on other system problems. (Langley Researcher, June 16/78, 1)
Under a cooperative agreement between NASA and the U.S. Navy, a Navy experimental plane would undergo in-place tethered-flight testing at LaRC's Impact Dynamics Research Facility, the Langley Researcher reported. The Navy's XFV-12A plane built by Rockwell International's Columbus Aircraft Div. was the only one of its kind, a prototype V/STOL aircraft designed to demonstrate the thrust-augmented wing concept in supersonic flight. The tests at LaRC had tethered the XFV-12A to the gantry by a single cable from a powerful winch mounted 210ft above ground. Static restraint tests kept the aircraft in place at various heights by ground cables attached to the nose and main landing gear, as its engines operated at full power. Using results of the static tests, LaRC had put the XFV-12A through dynamic tests, permitting greater freedom of motion, as he aircraft was not restrained by ground cables. The upper tether cable automatically reeled in as the aircraft maneuvered within the gantry, and a shock absorber on the winch cable guarded the airplane against loads greater than 2g. (Langley Researcher, June 16/78, 6)
ESA announced that the full-scale` propellant mockup of the European launcher Ariane (47m high, maximum diameter 3.8m) had left the integration site near Paris for its launch base at Kourou in French Guiana on the South American coast. Two Seine barges had transported three pressurized containers (one for each stage) to Le Havre, where they were loaded on a freighter bound for Cayenne. Tests of the mockup would begin in Aug. when the launcher would be erected on the pad for the first time.
ESA had planned 3mo of tests to check general conditions for launcher assembly and vehicle compatibility with ground facilities, as well as fueling and draining facilities and systems both on the ground and on the vehicle. Centre National d'Etudes Spatiales (CNES) would handle . transport, assembly, and test operations. Aerospatiale, the system integrator, would, evaluate dynamic and thermal behavior of the launcher under ambient climatic conditions in tests simulating vibrations like those at liftoff. ESA had planned four qualification launches between June 1979 and Oct. 1980 (ESA Release June 16/78)
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