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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…
The best-fit values of B and A from Figure 30 and Figure 31 have been listed for
convenient reference in Table 25. It is interesting to note that, for all breakup
conditions, the currently-used value of B = 1,000 provided a better data fit than any
other B that was investigated.
Table 25. Shaping Constants for LLVl
TB Breakup qa
(sec) (deg-lb/£t2) B A
290 none 1,000 1.85
20,000 2.60
10,000 2.70
5,000 2.75
290 none 10,000 2.45
20,000 1,000 2.60
10,000 1,000 2.70
5,000 1,000 2.75
No launch-area risk calculations were made for LLVl.
6.6 Shaping Constants for Other Launch Vehicles
Procedures for developing Mode-5 shaping constants A and B are fully· described in
this report. For Atlas, Delta, Titan, and LLVl, best-fit values of A were derived for four
breakup conditions (1) for the currently-used value of B = 1,000, and (2) for optimum-fit
values of B. For any new launch vehicle requiring risk calculations, the same
procedures should be followed to obtain suitable values for A and B.
As an alternative and less time-consuming process, values of A and B can be estimated
by comparing the new vehicle with one of the four vehicles referred to above and listed
in Table 26. If the configuration and trajectory of the new vehicle and one of the listed
vehicles are similar, values of A and B shown in the table for that vehicle and the
assumed breakup condition can be used. There may, of course, be no similarity
between the new vehicle and any of the listed vehicles. In that event and depending on
assumed breakup conditions, one of the mean values shown in the last row of the table
can be selected until better values can be developed.
Table 26. Summary of A Values for B = 1,000
Vehicle
IP Range (nm)
at 30 sec
Breakup qa (deg-lb/ ft2)
5,000 10,000 20,000 None
Atlas HAS
Delta-GEM
Titan IV
CLVl
0.3
5.2
1.9
33.4
3.45
4.30
3.50
2.75
3.20 2.75
3.10 2.90
3.25 2.95
2.70 2.60
1.90
1.90
2.00
1.85
Other vehicles 3.5 3.1 2.8 1.9
9/10/96 72 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.