Mar 8 1978

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NASA announced the successful launch of Landsat 3 (formerly Landsat-C), third of a series, from WTR at 12:54pm EST on March 5. Orbital parameters were: apogee, 913.96km; perigee, 897.3km; period, 103.108min; and inclination, 99.134°. Landsat was part of a U.S. program to develop remote sensing for improved earth resources management. The total program included development of remote-sensing instruments; data-analysis research using data from spacecraft, aircraft, and ground-truth sites; and a spaceflight program. Landsat 3 carried two piggyback payloads, the larger (approximately 34kg) being a plasma interaction experiment (PIX) by Lewis Research Center to measure plasma-coupling current and negative-voltage breakdown of a Solar array segment and a gold-plated steel disk. Objective of PIX was to. establish design guidelines, materials, devices, and test methods for controlling detrimental interactions between high-voltage systems and the space-plasma environment. The PIX would remain attached to the second stage of the Delta vehicle. The second piggyback payload, the 27.3kg Amsat Oscar communications-relay satellite built by radio amateurs, ejected from the, second stage approximately 12.3min after Delta separation from Landsat 3, would be available to amateur operators for science education, communications experiments, and search-and-rescue systems tests. The Oscar D carried two communications transponders having 1 to 2 watts of power output, and was magnetically stabilized.

Changes in the Landsat 3 payload included alteration of the return beam vidicon system to produce higher resolution panchromatic images for detailed ground mapping, and inclusion in the multispectral scanner (MSS) of a fifth band in the emitted terrestrial infrared radiation region. Objective of the MSS was to acquire multispectral high-spatial resolution (80m) images of solar radiation reflected from earth's surface, emitted infrared-radiation images of 240m resolution, and pan chromatic RBV images of 40m resolution. The MSS would obtain contiguous images about once every 18 days, weather permitting. The multispectral Images would aid research and operations demonstrations in agriculture and forestry resources, mineral and land resources, land use, water resources, marine resources, cartography, and the environment. Applications would include surveying land use; measuring factors causing stress on crops and forest; inventorying crops and forests; assessing crop vigor and health; classifying areas by geological or geomorphic characteristics; delineating promising areas for mineral exploration; determining water-runoff patterns and extent of snow cover; monitoring population movements and environmental hazards to man; mapping sea ice; and analyzing shorelines. Demonstration projects called Applications Systems Verification and Transfer (ASVT), focusing on landcover inventory for federal, regional, state, and private users, would also use Landsat 3 data.

The Landsat-C spacecraft (basically a Nimbus design modified to accommodate Landsat instruments and mission requirements) had the following parameters; weight, 90kg; mission margin, 51.4kg; stabilization type, 3-axis earth-oriented; stabilization accuracy, 0.7° pointing error, 0.04° per sec rate; average power available for experiments, 375 watts; thermal range, 10 to 30C; data storage capacity, 60min of video data (25.2 million bits). Launch vehicle was a 2-stage Thor-Delta approximately 116ft long and 8ft in maximum body diameter. The first stage was a McDonnell Douglas extended long-tank Thor booster incorporating 9 strap-on Thiokol Castor II solid-fuel rocket motors; second stage was powered by the TRW TR-201 liquid-fuel pressure-fed engine gimbal-mounted to control pitch and yaw through second-stage burn. A nitrogen gas-system using 8 fixed nozzles provided roll control during powered and coast flight, as well as pitch and yaw control after second stage cutoff. Two fixed nozzles fed from the propellant-tank helium pressurization system provided retrothrust after spacecraft separation. Total cost of the Landsat program (excluding costs of the launch vehicles, and including tracking and data network-systems support) would be $43.9 million through 1979. (MOR E-641-78-03 postlaunch] Mar 8/78, [prelaunch] Feb 22/78)

MSFC had been responsible for a variety of ground tests around the U.S. to prove flightworthiness of the Space Shuttle's solid-fuel rocket booster, the center newsletter reported. Each Shuttle mission would use 2 of the 578 097kg (600ton) SRBs, 45.46 meters (149ft) long and 3.7 meters (12ft) in diameter, each providing 12 232 550 newtons (2.75 million lb) of thrust for about 2min from the launch pad to burnout and separation at an altitude of 45.3km (27mi). Tests at MSFC had put loads on a "short" version of the booster to duplicate load conditions encountered on the launch pad, in flight, during parachute deployment, and in water impact and recovery. Other MSFC engineers had tested the flight system designed to gimbal (or swivel) the motor nozzles at the lower end of each booster to guide the Shuttle on a proper course.

Engineers at United Technologies Corp.'s Chemical System Div. near San Jose, Calif., had tested 8 small solid-fuel booster-separation motors, fired simultaneously to separate each SRB and move it away from the Shuttle during flight. Each end of the two boosters would carry 4 motors, a total of 16 on each flight. These would have about 88 960 newtons (20 000lb) of thrust and would fire only about 1 sec each to accomplish separation. The separation motor had completed development testing; the Calif. test series would qualify it for flight.

Thiokol Corp.'s Wasatch Div. near Brigham City, Utah, had run full duration full-thrust static firings on the SRB; high-speed sled runs in New Mexico had tested one phase of the SRB's parachute-recovery system (deployment of the pilot chute only) to see whether the nosecap of the system, when ejected, would clear the vehicle without becoming entangled; and the National Parachute Test Range at El Centro, Calif., had conducted airdrops of the entire parachute system. Other tests of SRB's electrical system and prelaunch checkout system were in progress. (Marshall Star, Mar 8/78, 4)

NASA officials had unveiled the prototype of a parachute-cleaning machine strongly resembling a carwash operation, Today reported. If approved, the facility would become part of KSC's system to refurbish Space Shuttle parachutes. Each of the Shuttle's two solid-fuel rocket boosters jettisoned into the Atlantic Ocean shortly after launch would carry 4 nylon parachutes; both the boosters and the parachutes were designed for recovery and return to KSC for another launch. The carwash-type facility would rid the parachutes of salt water before washing and drying them in large machines. The current system had rinsed parachutes in the same water they were washed in; the new system would save some of the 20 000gal of water now used by the washing machine. In the carwash-type system, parachutes would move along an overhead rail, rinsed 3 times by water sent through high-pressure nozzles. The 3 main parachutes were 230ft long and 115ft in diameter, weighing 16001b dry and 20001b wet; the fourth parachute measured 145ft in length and 54ft in diameter, and would weigh 12001b dry and 14001b wet. On completion, the new system should require 2hr to wash and 2hr to dry each parachute. (Today, Mar 8/78, 8A)

JSC announced plans for the week-long ninth annual lunar and planetary science conference focusing on the moon and other worlds, with the Lunar and Planetary Institute of Houston as co-host. Topics of presentations would include the formation of the solar system; new discoveries in moon rocks; the histories of planets; meteorites containing material from ancient stars; and comparative studies of Mars, Venus, and the earth. For the third consecutive year, the USSR would send a delegation. A number of topics would be emphasized: constraints on structures; composition and history of planetary interiors; characteristics and movement of material on lunar, planetary, and asteroid surfaces; characteristics and evolution of volcanic landforms; characterization and evolution of planetary crusts; nature and effect of impact processes; extraterrestrial materials; solar, interplanetary, and interstellar probes; and earliest history of the solar system. JSC had scheduled special sessions on industrial development of near-earth space, on origin of the solar system, on the future of planetary exploration, and on Mars and Mercury. (JSC Release 78-40)

INTELSAT announced it had awarded the Yardney Electric Corp. of Pawcatuck, Conn., a $149 365 contract to develop an advanced nickel hydrogen battery to demonstrate flight acceptance for use in future INTELSAT communications-satellite programs. The contract terms called for design, fabrication, testing, and delivery of two batteries by March 1979. INTELSAT had pioneered development of this technology, expected to improve energy density, increase cyclic capability, and prolong battery lifetime and reliability. (INTELSAT Release 78-6-1)

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