Apr 4 1968
From The Space Library
NASA's Apollo 6 (AS-502) was successfully launched from KSC Complex 39A at 7:00 am EST on mission to qualify Saturn V launch vehicle for future manned space flights. Primary objectives were to demonstrate structural and thermal integrity and compatibility of launch vehicle and spacecraft; confirm launch loads and dynamic characteristics; demonstrate S-II/S-IC and S-IVB/S-II stage separations; verify operation of propulsion (including S-IVB restart), guidance and control (optimum injection), and electrical systems; evaluate performance of emergency detection system (EDS) in closed-loop configuration; and demonstrate mission support facilities and operations required for launch, mission conduct, and command module (CM) recovery. Launch vehicle 1st-stage performance was near nominal, but two of five 2nd-stage J2 engines shut down prematurely, causing remaining 2nd-stage engines and 3rd-stage engine to burn longer than planned. As result, spacecraft and 3rd stage entered elliptical parking orbit with 223.1-mi (395.1-km) apogee, 107-mi (172.1-km) perigee, and 89.8-min period instead of planned circular orbit of 115-mi (175-km) altitude. When 3rd stage failed to reignite on command after two orbits as planned, NASA switched to alternate mission, firing service propulsion system (SPS) to place spacecraft into trajectory with 13,823-mi (22,225.4-km) apogee. Since insufficient propellant remained after extended burn, second SPS burn was not attempted and CM reentered at 22,376 mph, just under planned 25,000-mph rate. Spacecraft splashed down 50 mi off target in Pacific 9 hr 50 min after launch and was recovered in good condition by U.S.S. Okinawa. Preliminary assessment indicated four of five primary objectives were attained, even though launch vehicle performance and S-IVB restart and guidance control (optimum injection) were not fully successful [see April 11 and 24]. Apollo 6 was second flight for Saturn V launch vehicle and boilerplate lunar module (LM) and fourth for operational Block I command/service module (CSM) . Spacecraft had been modified to include Block II heatshield and instrumentation for unmanned configuration, delete crew provisions, incorporate new unified quick-operating hatch and movie camera to record launch escape system (LES) jettison and reentry conditions, and relocate sequence camera for earth landmark photography. Apollo 4 (launched Nov. 9, 1967) and Apollo 5 (launched Jan. 22, 1968) had both been highly successful, completing inflight tests of all major pieces of Apollo hardware. Apollo program was directed by NASA Office of Manned Space Flight; KSC was responsible for Apollo spacecraft development, MSFC for Saturn launch vehicle development, and SC for launch operations. Tracking and data acquisition was managed by GSFC under overall direction of NASA Office of Tracking and Data Acquisition. (NASA Proj Off; NASA Release 68-54K; W Post, 4/5/68, A18; UPI, W Star, 4/5/68, A3)
NASA test pilot William H. Dana flew X-15 No. 1 to 187,500-ft altitude and 3,546 mph (mach 5.27) to test spray-on foam insulation, much lighter than previously used insulation, for use on Saturn V 2nd stage. Test, from Edwards AFB, was satisfactory, with X-15 performing in maximum-heating design trajectory close to that of Saturn V and sustaining temperatures of up to 1,500°F. (X-15 Proj Off; MSFC Release 68-69; AP, P Inq, 4/5/68)
Nike-Tomahawk sounding rocket was launched by NASA from Churchill Research Range carrying GSFC payload to gather data on charged particle fluxes associated with aurora and to investigate distribution of electric fields in ionosphere, occurrence of radio noise, and ionospheric electron densities during auroral displays. Rocket and instruments per- formed satisfactorily; good data were acquired. (NASA Rpt SRL)
ARC scientists Dr. William L. Quaide and Verne R. Oberbeck had developed method of calculating lunar soil depths using measurements based on Lunar Orbiter photos and Surveyor photos and surface analyses, NASA announced. Studies indicated that many of moon's smaller craters and much of soil and fragmental material on lunar surface were result of meteoroid impacts. By simulating impacts in laboratory and comparing results with photos of lunar craters scientists identified four crater types: (1) craters with up to 12-ft dia, round bottoms, and depths 25% of their diameter; (2) craters with 12- to 22-ft dia, flat bottoms, and central mound; (3) craters with 22- to 30-ft dia, flat bottoms, and no mound; and (4) craters with diameter greater than 30 ft with second crater gouged in flat bottom. Thick layer of fragmented material, calculated by new method to be up to 20 yd deep, coincided with densely cratered areas to support impact theory. (NASA Release 68-59; SBD, 4/5/68, 202)
Model of wheel-shaped planetary landing craft, sterilized by heat and dropped from 250-ft altitude by Jet Propulsion Laboratory, operated successfully after impacting dry lake in Mojave Desert at 80 mph-major step in demonstrating feasibility of sending lightweight scientific landing capsule to Mars. Craft's radio transmitter turned on 30 sec after craft struck surface and operated 20 min. Anemometer deployed automatically 3 min after impact, to measure wind velocity. Following mission profile identical to projected Mars surface operations, radio turned on again 22 hr after initial transmission (when earth would again be in view). Signals from three-watt transmitter were received for another 40 min to conclude test. Craft was powered by 12-cell, silver-zinc battery, first known to survive both heat sterilization and high-velocity impact. (NASA Release 68-69; JPL Release 473; JPL PIO)
USAF's Lincoln Experimental Satellite (Les V) (launched July 1, 1967), first all solid-state UHF band comsat, had been used in first network of tactical terminals to include a comsat, first air-to-air link via satellite relay, and first communications link from high latitudes via satellite as part of USAF program to improve communications between aircraft. Les V was testing UHF teletype system which relayed 60-wpm messages over ground distances of up to 8,000 mi. Satellite's 20,000-mi-altitude orbit allowed line of sight stretching nearly halfway around the world. USAF proposed using system for communications between low-altitude attack aircraft and rear area controllers, for USAF worldwide logistic control and status reporting system, and for strike and reconnaissance report. ing. (AFSC Release 23.68)
Dr. William H. Pickering, Director of Cal Tech's Jet Propulsion Laboratory, spoke at Space Forum sponsored by American Institute of Aeronautics and Astronautics, American Astronautical Society, and Institute of Environmental Sciences in Washington, D.C. Describing first decade in space as "most productive . . . in history of technology," he forecast manned lunar operations including lunar laboratories before end of second decade; tour of Jupiter, Saturn, Uranus, and Neptune by single spacecraft in 1977; and dramatic yield from growing applications of near-earth satellites. He urged initiation of "orderly planning cycle" to replace major programs being phased out. Emphasis of next phase was likely to be "gleaning more benefits" from space dollar expenditure. National Space Council estimated annual return from space would markedly exceed expenditures in 10 yr. (Text)
NASA would negotiate $3.5-million, one-year, cost-plus-fixed-fee contract with General Electric Co.'s Apollo Systems Div. for Apollo Applications engineering support. GE, under direction of NASA Hq. Apollo Applications Program Office, would provide engineering support in areas of quality and reliability, configuration and data management, test, and checkout. (NASA Release 68-61)
MSFC contract activity: RCA was awarded $1,293,640 contract to modify RCA 110 computer module boards, by systematically incorporating improved solder design. IBM was issued $1,523,282 supplemental agreement for adjustment and implementation of configuration management for fabrication, assembly, checkout, and delivery of 27 Apollo/Saturn instrument unit stages and other support equipment. Air Products and Chemicals, Inc., received $2,249,364 contract extension to supply 12 million lb liquid hydrogen by March 31, 1969, to MSFC, purchasing agent for Government agencies and their supporting contractors in eastern U.S. Three one-year contract renewals, effective through March 31, 1969, were awarded for MSFC support services: $10.5 million to Brown Engineering Co. for services in Propulsion and Vehicle Engineering Laboratory, $4,504,000 to SPACO Inc. for services in Quality and Reliability Assurance Laboratory, and $2,273,000 to Hayes International for services in Manufacturing Engineering Laboratory. (MSFC Releases 68-64, 68-65, 68-66, 68-67)
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30
