Documents / Report

Department of the Air Force Report, 1996

U.S. Department of War · 1996-09-10 · 181 pages · text from the file's own layer

This final report, dated September 10, 1996, was prepared by the Research Triangle Institute for the Department of the Air Force's 45th and 30th Space Wing safety offices. Titled Modeling Unlikely Space-Booster Failures in Risk Calculations, it shows how rare Mode-5 failures, in which a rocket veers well off its intended flight line, are modeled in the DAMP risk-analysis program. An appendix lists Atlas, Delta, Titan and Thor launch and failure histories through August 1996.

From the source:Release of 2026-05-08 Incident: 9/10/96, N/A. This report describes the Modeling of Unlikely Space-Booster Failures in Risk Calculations, documenting historical launch failure modes and recommending corrective actions to address them using novel modelling techniques.

  • p. 88 …Vehicle loses control at or shortly after liftoff, with all flight directions equally likely. Destruct is…
  • p. 106 …121 (8) Missiles/Space Vehicle Files, 45th Space Wing, Wing Safety, Mission Flight Control and Analysis…
  • p. 111 …Such behavior did not necessarily prevent the attainment of some, or even all, mission objectives. 50…
  • p. 131 …Due to excess speed, spacecraft passed 22,000 miles in front of moon, and primary mission…
  • p. 132 …Although Atlas performance was satisfactory, the mission was apparently a failure. No other data available. 134…
  • p. 133 …A flight-control malfunction occurred at about 15 seconds at the start of the pitch program…
  • p. 137 …Vehicle became unstable when B2 pitch control was lost at 121 seconds. Loss of pitch control…
  • p. 138 …The missile then lost attitude control, executing a hard yaw rate tum throughout and beyond the…
  • p. 139 …of the rate gyro or an electrical failure in the pitch channel of the flight control…
  • p. 140 caused yaw and roll rates that the flight control system could not correct. As a result…
  • p. 151 …Attitude control lost during second stage coast period. Third stage spun up, but did not fire…
  • p. 153 …One solid-rocket motor carried to MECO, but mission was still a complete success. 102. SMS…
  • p. 169 …Missile tumbled out of control at 130 seconds, then broke up. 104. IHA (65-210), 1…
  • p. 170 …Nominal mission through transtage second burn shutdown. Attitude control system engine failed to shutdown following vernier…
  • p. 171 …However, satellite propulsion system malfunctioned putting satellite in uncontrollable position with no possibility of restoring mission…
  • p. 172 …control until propellant depletion. Trajectory inaccuracies were compensated for during Stage-2 burn, and the mission…
  • p. 180 …Missiles/Space Vehicle Files, 45th Space Wing, Wing Safety, Mission Flight Control and Analysis (SEO), 1957…
D.2.2 Atlas Failure Narratives
The following narratives provide the available details about each Atlas failure since the
beginning of the Atlas program. The narratives are numbered to match the flight-
sequence numbers in Section D.2.1. •
1. 4A, 11 June 57, Response Mode 4T, Flight Phase 1: Flight appeared normal for
24.7 seconds when drop in fuel supply to B2 engine produced a drop in
performance and shutdown Both engines moved to hardover in pitch to
compensate for thrust asymmetry. The Bl engine failed at 27 seconds. A fuel fire
was observed in aft end after thrust was lost. The missile continued to rise,
reaching an altitude of 9,800 feet at 38 seconds. Missile was destroyed by safety
officer 50.1 seconds after liftoff. Thrust unit and other hardware impacted about
1/4 mile south of launch pad (105° flight azimuth).
2. 6A, 25 Sep 57, Response Mode 4, Flight Phase 1: Flight appeared normal until
about 32.5 seconds after liftoff, when performance level of both engines dropped
to 35% of normal. Both engines shut down at 37 seconds. Missile was destroyed
at 63 seconds. Loss of thrust was due to loss of LOX regulator in the booster gas
generator. Major components impacted about 8000 feet downrange and 1000 feet
right of flight line. •
5. 13A, 7 Feb 58, Response Mode 4, Flight Phase 1: The B2 turbopump and engine
stopped operating about 118 seconds due either to loss of 102 regulator reference
pressure or a control-system failure. The Bl engine ceased to operate 0.3 second
later. Failure was attributed to shorting of a vernier engine feedback transducer
due to aerodynamic heating. Propellant sloshing that began building up at about
100 seconds led to missile instability. Vehicle broke up at 167 seconds. Impact
occurred about 280 miles downrange and about 3 miles crossrange.
6. llA, 20 Feb 58, Response Mode 4T, Flight Phase 1: Vernier engine was hardover
from 51.9 seconds to 89.4 seconds, then returned to null until 104 seconds, then
went hardover again. Other systems appeared normal until 109.6 seconds, when
divergent oscillations began in rate-gyro outputs and engine positions. All
engines reached stops by 114.3 seconds and continued thereafter to oscillate
between stops until loss of thrust at 124.8 seconds. Vehicle breakup occurred one
second later. Probable cause of oscillation was a component failure in flight
control system. Vehicle impacted about 105 miles downrange and 8 miles right of
flight line.
7. 15A, 5 Apr 58, Response Mode 4, Flight Phase 1: Booster engines shut down
prematurely at 105.3 seconds (instead of planned 127 seconds) due to Bl
turbopump failure. Since Bl chamber pressure drives the gas generator, the B2
turbopump and engine also stopped. Impact was 180 miles downrange and
slightly left of flight line.
9/10/96 115 RTI

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Report, from the pursue collection. The PDF is mirrored here; the original link is above. 181 pages are in the text index: search them above, or from the library's search.