Union Calendar No. 600 99th Congress, 2d Session - - - - - - - - - - - - - House Report 99-1016 INVESTIGATION OF THE CHALLENGER ACCIDENT REPORT OF THE COMMITTEE ON SCIENCE AND TECHNOLOGY HOUSE OF REPRESENTATIVES NINETY-NINTH CONGRESS SECOND SESSION OCTOBER29, 1986.-Committed to the Committee of the Whole House on the State of the Union and ordered to be printed U.S. GOVERNMENT PRINTING OFFICE 64-420 0 WASHINGTON : 1986 COMMITTEE ON SCIENCE AND TECHNOLOGY DON FUQUA, Florida, Chairman ROBERT A. ROE, New Jersey MANUEL LUJAN, JR.; New Mexico GEORGE E. BROWN. JR.. California ROBERT S. WALKER, Pennsylvania JAMES H. SCHEUER, New York F. JAMES SENSENBRENNER, JR., MARILYN LLOYD, Tennessee Wisconsin TIMOTHY E. WIRTH, Colorado CLAUDINE SCHNEIDER, Rhode Island DOUG WALGREN, Pennsylvania SHERWOOD L. BOEBLEKT, New York DAN GLICKMAN, Kansas TOM LEWIS, Florida ROBERT A. YOUNG, Missouri DON RI'ITER, Pennsylvania HAROLD L. VOLKMER, Missouri SID W. MORRISON. Washinaton BILL NELSON, Florida RON PACKARD, California - STAN LUNDINE, New York JAN MEYERS, Kansas RALPH M. HALL, Texas ROBERT C. SMITH, New Hampshire DAVE McCURDY, Oklahoma PAUL B. HENRY, Michigan NORMAN Y. MINETA, California HARRIS W. FAWELL, Illinois BUDDY MAcKAY,'. Florida WILLIAM W. COBEY, JR.,North Carolina TIM VALENTINE, North Carolina JOE BARTON, Texas HARRY M. REID, Nevada D. FRENCH SLAUGHTER, JR., Virginia ROBERT G. TORRICELLI, New Jersey DAVID S. MONSON, Utah RICK BOUCHER, Virginia TERRY BRUCE, Illinois RICHARD H. STALLINGS, Idaho BART GORDON, Tennessee JAMES A. TRAFICANT, JR., Ohio JIM CHAPMAN, Texas HAROLDP. HANSON,Executive Director ROBERTC. KETCHAM,General Counsel REGINA A. DAVIS,Chief Clerk R. THOMASWEIMER, Republican Staff Director CHALLENGERACCIDENT REPORT STAFF TASK GROUP ROBERTC. K~HAM,General Counsel ROBERTE. PALMER RADP~RDBYERLY, Jr. GEORGES. KOPP RONALDE. WILLIAMS HARRYS. DAWSON,Jr. PATRICIAG. GARFINKEL HARRIETJ. SMITH A. SCOTT CROSSFIELD NEUONL. MILDER CAROLYNC. GREENFELD CAROLYNJ. RADABAUGH DAVIDD. CLEMENT JAM=PAUL SHIRLEY J. WATSON GLORIAJ. DUNDERMAN 'Ranking Republican Member. "Serving on Committee on the Budget for 99th Congress (11) LETTER OF SUBMITTAL U.S.HOUSE OF REPRESENTATIVES, Washington, DC, October 29, 1986. Hon. THOMASP. O’NEILL,Jr., The Speaker of the US.House of Representatives, Washington, DC. DEARMR. SPEAKER: By direction of the Committee on Science and Technology, 1 hereby submit the Committee’s investigative report on the Chal- lenger accident. The report was approved by the Committee on Oc- tober 7, 1986. The report was carried out under the direction of the Ranking Majority Member, Robert A. Roe, who chaired the hear- ings and instructed the Committee staff assigned to the investiga- tion. Sincerely, DONFUQUA, Chairman. Enclosure. (111) LETTER OF TRANSMITTAL U.S. HOUSEOF REPRESENTATIVES, COMMITPEEON SCIENCEAND TECHNOLOGY, Washington, OC, October 29, 1986. To Robert A. Roe, Ranking Majority Member, Committee on Science and Technology. DEARMR. CHAIRMAN: I am forwarding this investigative report on the Challenger Acci- dent prepared at your request. On your instructions, the staff has carefully reviewed the infor- mation made available to the Committee and prepared the neces- sary findings and recommendations. The task was enormous and has been done in a careful and painstaking manner. I am especial- ly grateful to all the staff which is listed on the inside cover of the report for their professional and thorough application to this im- portant report. We worked in a collegial manner and on a com- pletely bipartisan basis. I particularly want to thank the three group leaders, Ron Williams, Terry Dawson and Harriet Smith who headed up the respective subgroups for the Accident, the Tech- nical, and the Management Issues. Sincerely, ROBERTC. KETCHAM,General Counsel. CONTENTS Page I. INTRODUCTION......................................... 11. CONCLUSIONS........................................... 111. C~MPILATIONOF ISSUES,FINDINGS, AND RECOMMENDATIONS.......................... IV. B~CKGROUND........................................................................................................... 35 V. THEACCIDENT ......................................................................................................... 39 ................................ 64 ................................... 65 ............................... ......................... ...................... ...................... VII. CASINGJOINT DESIGN ........ ............................. ...................... VIII. LAUNCHOPERATIONS ......... Ix. DEFINITIONOF TERMSAND X. APPENDICES......................... V-A .............................. .......................... lVlll vrrr Page V-G ... .............. .................................................................. 285 286 288 290 292 319 321 327 369 376 278 280 VIII-B ...................... .. ..... .......................... .... .. .. .. 384 VIIIC.......... .......... .................... ................................................. ..................... 387 VIII-D ............................................................ ................................................. 393 .. , . , . , . 395 .. , . , . 406 ... ... .. , . , . * .. , . , . , . , . , . 417 VIII-H .......................................................... ................................................... 425 VIII-I ............................................................................................................. .. 428 VIII-J .............................. ................................ ................................................ 434 VIII-K .. .. .. .. .. .. .. ................................... ,.,., ......,,.... 438 ..... .. .. .. 442 Union Calendar No. 600 99~~CONGRESS REPORT 2d session } HOUSE OF REPRESENTATIVES I gg-io16 INVESTIGATION OF THE CHALLENGER ACCIDENT OCTOBES29, 1986.-Committed to the Committee of the Whole House on the State of the Union and ordered to be printed Mr. FUQUA,from the Committee on Science and Teshnology, submitted the following REPORT I. INTRODUCTION On January 28, at 11:39 a.m., the Space Shuttle Challenger and its crew suffered a tragic accident during launch. That same day the House of Representatives adopted H. Res. 361 which expressed the profound sorrow of the House for the tragedy and offered con- dolences to the families of the Challenger crew members. During consideration of the resolution Chairman Fuqua informed the full House of Representatives that, in conformance with its oversight responsibilities, the Committee on Science and Technolo- gy would conduct a comprehensive investigation into the cause of this accident. This report is the result of the Committee’s inquiry. It contains the best efforts of the Committee to review the work of the Presi- dential Commission on the Space Shuttle Challenger Accident (hereafter referred to as the Rogers Commission) and the work of the National Aeronautics and Space Administration (NASA) in in- vestigating the causes of the accident, and reviewing the recom- mendations to resume safe flight. In addition to reviewing the five volumes of the Rogers Commis- sion Report, the Committee also had direct on-line access to the entire Rogers Commission data base, which included full-text and document retrieval capability. The findings and recommendations contained in this report are the product of the Committee’s own extensive hearing record, ’ Report of the Presidential Commission on the Space Shuttle Challenger Accident, Volumes I- V, Washington, D.C., June 6, 1986. (Hereafter referred to as Rogers Commission Report.) (1) 2 which includes materials submitted for the record, staff investiga- tions, interviews, and trips. It should be understood that the role of this Committee is differ- ent from that of the four-month Rogers Commission. The Commit- tee, which authorized the funds and reviewed the lengthy develop- ment process which led to the successful Shuttle program, has a re- sponsibility to insure that the tragic accident, and those events that led up to it, are understood and assimilated into all levels and activities of NASA so that safe manned space flight can be re- sumed. In carrying out its annual authorizing responsibilities, the Com- mittee endorses the programs and activities of NASA, and func- tions as a key player in the legislative activities of our federal system. As part of the fulfillment of this role, the Committee has reviewed the report of the Rogers Commission, called upon numer- ous witnesses, and utilized many members of its staff to prepare and review the material that has produced this report. The Committee has been most fortunate in its work due to the diligent and thorough investigation undertaken by the Rogers Com- mission and the NASA investigation panels that supported the Commission. The Commission’s exhaustive efforts to achieve com- pleteness as it came to grips with a very complex technical and management system are very commendable, and will serve as a model for future Presidential Commissions. The Committee wishes to express its appreciation for the assist- ance of the House Administration Committee, the Rogers Commis- sion staff, and the Justice Department’s Office of Litigation Sup- port, Civil Division. Each of these groups was very cooperative and helpful in providing the access to, and equipment for, the Challeng- er accident data base needed by the Committee to do its work. In addition, the Committee very much appreciates the assistance of NASA personnel who responded to numerous requests for briefings and documents