DOW-UAP-D048, Department of the Air Force Report, 1996

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RESEARCH TRIANGLE INSTITUTE Contract No FO4703-91-C-0112 RTI Report No. RTl/5180/77-43F Modeling Unlikely Space-Booster Failures in Risk Calculations Final Report Prepared for Department of the Air Force 45th Space Wing (AFSPC) Department of theA ir Force 30th SpaceW ing (AFSPC) Distribution authorized to US Government agencies and their contractors to protect administrative/ operational use data, 10 September 96. Other requests for this document shall be referred to the 30th Space Wing (AFSPC) Safety Office (30 SW/SE), Vandenberg AFB, CA 93437, or 45th Space Wing (AFSPC) 'mJC QUALITY INSPECTED

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Contract No. FO4703-91-C-0112 RTI Report No. RTI/5180/77-43F Modeling Unlikely Space-Booster Failures in Risk Calculations Final Report Prepared by Robert M. Montgomery Research Triangle Institute Center for Aerospace Technology Launch Systems Safety Department Prepared for Department of the Air Force 45th Space Wing (AFSPC) Department of the Air Force 30th Space Wing (AFSPC) Vandenberg AFB, CA 93437 Distribution authorized to US Government agencies and their contractors to protect administrative/ operational use data, 10 September 96. Other requests for this document shall be referred to the 30th Space Wing (AFSPC) Safety Office (30 SW/SE), Vandenberg AFB, CA 93437, or 45th Space Wing (AFSPC)

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Form Approved REPORT DOCUMENTATION PAGE Public tel)Ort1ng burden for this collection of information is estimated to average 1 hour per response. induding the time for reviewing instructions, searching exi5ting data sources. gathering and maintain in!,! the data needed, and completing and rev,ew,ng the collection of Information. Send comments r~ardlng tlils burden estimate or any other aspect of this collection of Information, including suggestions tor reducing this burden. tO Washington Headquarters Services, Directorate or Information Operations and Reports, 1215 Jefferwn Davis Highway, Suite 1204, Arlington, VA 12202-4302, and to the Office of Management and Budget. Paperwork Reduction Project(0704-0188), Washington. DC 20503. 1. AGENCY USE ONLY (Leave blank) ~.• REPORT DATE 1 3. REPORT TYPE AND DATES COVERED 4. TITLE AND SUBTITLE 5. FUNDING NUMBERS f.1odeling Unlikely Space-Booster Failures in Risk Galculations C: F04703-91-C-o112 Robert M. Montgomery REPORT NUMBER Research Triangle Institute * ACTA, Inc. ** Torrance, CA 90505 Department of the Air Force (AFSPC) Department of the Air Force (AFSPC) AGENCY REPORT NUMBER 30th Space Wing 45th Space Wing Vandenberg AFB, CA 93437 Patrick AFB, FL 32925 11. SUPPLEMENTARY NOTES " Prime Contractor Distribution authorized to US Government agencies and their contractors to protect administrative/operational use data; 10 September 96. Other requests for this document shall be referred to the 30th Space Wing (AFSPC) Safety Office (30 SW/SE),Vandenberg AFB, CA 13. ABSTRACT (Maximum 200 words) Missile and space-vehicle performance histories contain many examples of failures that cause, or have the potential to cause, significant vehicle deviations from the intended flight line. In RTl's risk-analysis program, DAMP, such failures are referred to as Mode-5 failure responses. Although Mode--5 failure responses are much less likely to occur than those that result in impacts near the flight line, risk-analysis studies are incomplete without them. This report shows how Impacts from Mode-6 failures are modeled in program DAMP. The impact density function used for this purpose contains two shaping constants that control the rate at which the density function drops In value as the angular deviation from the flight line and the impact range increase. Certain Mode--5 •malfunctions are simulated, and the two shaping constants then chosen by trial and error so that impacts from the simulated malfunctions and the theoretical density function are in close agreement. An appendix to the report contains alisting and brief narrative failure history of the A~as, Delta, and Titan missile and space-vehicle launches from the Eastern and Western Ranges from the beginning of each program through August 1996. Each entry gives the vehicle configuration, whether the flight was asuccess, the flight phase in which any anomalous behavior occurred, and aclassification of vehicl~ behavior in accordance with defined failure-response modes. launch risk, unlikely failure modeling, booster failure probabilities 180 16. PRICE CODE 17. SECURITY CLASSIFICATION 18. SECURITY CLASSIFICATION 19. SECURITY CLASSIFICATION 20. LIMITATION OF ABSTRACT OF REPORT OF THIS PAGE OF ABSTRACT Unclassified lJnclassified lnclasslfled SAR Prescribed by AIIISI Std. Z39-18

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Missile and space-vehicle performance histories contain many examples of failures that cause, or have the potential to cause, significant vehicle deviations from the intended flight line. In RTI's risk-analysis program, DAMP, such failures are referred to as Mode-5 failure responses. Although Mode-5 failure responses are much less likely to occur than those that result in impacts near the flight line, risk-analysis studies are •i ncomplete without them. This report shows how impacts from Mode-5 failures are modeled in program DAMP. The impact density function used for this purpose contains two shaping constants that control the rate at which the density function drops in value as the angular deviation from the flight line and the impact range increase. Certain Mode-5 malfunctions are simulated, and the two shaping constants then chosen by trial and error so that impacts from the simulated malfunctions and the theoretical density function are in close agreement. An appendix to the report contains a listing and brief narrative failure history of the Atlas, Delta, and Titan missile and space-vehicle launches from the Eastern and Western Ranges from the beginning of each program through August 1996. Each entry gives the vehicle configuration, whether the flight was a success, the flight phase in which any anomalous behavior occurred, and a classification of vehicle behavior in accordance with defined failure-response modes. Various filtering or data weighting techniques are described. The empirical data are then filtered to estimate (1) failure probabilities for Atlas, Delta, and Titan, and (2) percentages of future failures that will result in Mode-5 (and other Mode) responses.

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Table of Contents · 3.2 Effects of Shaping Constant on DAMP Results ........................................................ 9 4. Methodology for Assessing Failure Probabilities ........................................................... 13 5.2 Relative and Absolute Probabilities for Response Modes ..................................... 24 6.1.4 Malfunction-Tum Results for Atlas IIAS ...................................................... 35 6.2 Shaping Constants for Atlas IIAS ............................................................................ 37 6.2.3 Effects of Mode-5 Constants on Ship-Hit Contours ..................................... 51 6.2.4 Range Distributions of Theoretical and Simulated Impacts. ....................... 58