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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.
“Mission Control”17 pages
Traditionally, a value of B = 1,000 has been used by the 45 SW/SE in ship-hit calculations, and by RTI in performing launch-area risk analyses for the 45 SW/SE. Using this value. of B, for each vehicle values of A were found that produced a good match between simulated and theoretical data. The results for qa = 5,000, 10,000, and 20,000 deg-lb/ft2 are given in Table 31. As discussed earlier in the report, no single value of A could be found that produced a good fit over the entire 180° sector, although with one exception a good match did exist in the uprange portion of the sector from about ±90° to ±180°. For launches from Cape Canaveral, most population centers are located in this uprange sector. For any launch-area population centers located in the downrange sector, the risks are almost surely dominated by the Mode-4 failure response. Table 31. Summary of A Values for B = 1,000 Flight TB Breakup qa (deg-lb/ft2) Vehicle Phase (sec) 5,000 10,000 20,000 Atlas HAS 0-2 280 3.45 3.20 2.75 Delta-GEM 0-1 270 4.30 3.10 2.90 Titan IV 0-1 300 3.50 3.25 2.95 LLVl 0-2 290 2.75 2.70 2.60 Other vehicles --- --- 3.5 3.1 2.8 Other values of B were investigated to find combinations of B and A that provided the best possible data fits over the largest possible portion of the 0° to 180° sector. Although no combinations of A and B could be found that produced good fits for the entire 180° sector, the values shown in Table 32 extended the fit from the uprange direction to within about 40° of the downrange direction. Table 32. Summary of Optimum Mode-5 Shaping Constants Flight TB Breakupqa Vehicle · Phase (sec) (deg-lb/ ft2) B A Atlas 0-2 280 5,000 5,000,000 6.30 Delta 0-1 270 5,000 4 3.50 Titan 0-1 300 5,000 1,000 3.50 LLVl 0-2 290 5,000 1,000 2.75 Launch-area risk calculations were made for Atlas and Delta to ascertain the effects of using radically different values of A and Bin the Mode-5 impact-density function. For example, for a breakup qa of 5,000 deg-lb/ft2, values of A= 3.45 and B = 1,000 from Table 31 and A= 6.30 and B = 5,000,000 from Table 32 were used to determine total Mode-5 launch-area risks for an Atlas HAS launch from Complex 36. The total risks differed by about 10%. (Other results for Atlas HAS are given in Table 21, and for Delta in Table 23.) Other calculations for Atlas and Delta show that the value of B is not 9/10/96 77 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.