NTSB · Safety Recommendation
Safety Recommendation A-93-100
Recommendation
THE NTBS RECOMMENDS THAT THE ORBITAL SCIENCES CORPORATION: REQUIRE, AS PART OF ELV LAUNCH PLANNING DOCUMENTATION: MANDATORY REST PERIODS BEFORE THE LAUNCH FOR KEY PARTICIPANTS THAT PROVIDE FOR AN ADEQUATE AND SPECIFIED TIME PERIOD FOR UNINTERRUPTED SLEEP. THE QUANTITATIVE CRITERIA FOR SUCH REST PERIODS SHOULD BE DEVELOPED BY APPROPRIATE HUMAN PERFORMANCE EXPERTS TO ENSURE APPLICABILITY TO THE ASSIGNED TASKS.
Safety Issue and Context
ON FEBRUARY 9, 1993, ABOUT 0930 EASTERN STANDARD TIME, THE LAUNCH SEQUENCE FOR AN ORBITAL SCIENCES CORPORATION (OSC) PEGASUS EXPENDABLE LAUNCH VEHICLE (ELV) WAS ABORTED BY THE NATIONAL AERONAUTICS AND SPACE ADMINISTRATION (NASA) RANGE SAFETY OFFICERS, IN ACCORDANCE WITH A PREVIOUSLY ESTABLISHED LAUNCH CONSTRAINT. SEVERAL SECONDS LATER, THE LAUNCH SEQUENCE WAS REINITIATED BY THE OSC TEST CONDUCTOR, AND THE MISSILE SEPARATED UNEVENTFULLY FROM ITS CARRIER AIRCRAFT. THE IGNITION AND STAGING OF THE PEGASUS AND ITS SUBSEQUENT DEPLOYMENT OF TWO SATELLITES INTO LOW EARTH ORBIT WERE ALSO UNEVENTFUL. THERE WERE NO INJURIES TO PERSONNEL INVOLVED IN THE MISSION AND NO DAMAGE TO MISSION ASSETS.
Response History
June 16, 1997 · NTSB Correspondence · Orbital Sciences Corporation
OUR RECORDS INDICATE THAT THE SAFETY BOARD INITIALLY RECEIVED A RESPONSE FROM YOUR CORPORATION ON 9/8/93, CONCERNING THESE RECOMMENDATIONS. HOWEVER, WE HAVE NOT SINCE RECEIVED ACKNOWLEDGMENT THAT THESE RECOMMENDATIONS HAVE BEEN IMPLEMENTED. IF WE DO NOT RECEIVE A RESPONSE FROM YOU WITHIN 45 DAYS, THESE RECOMMENDATIONS WILL BE CLASSIFIED "CLOSED--UNACCEPTABLE ACTION."
May 9, 1994 · NTSB Correspondence · Orbital Sciences Corporation
THE BOARD NOTES THAT THE OSC LAUNCH TEAM OBSERVED OSC'S CREW REST REQUIREMENTS. HOWEVER, THE BOARD BELIEVES THAT THE OSC SHOULD DEVELOP MANDATORY PRELAUNCH REST PROCEDURES THAT WOULD PROVIDE KEY PARTICIPANTS THE OPPORTUNITY TO GET A SPECIFIED NUMBER OF HOURS OF UNINTERRUPTED SLEEP BEFORE ASSUMING DUTIES ON THE LAUNCH TEAM. ONLY BY DEVELOPING CRITERIA, SUCH AS 8 HOURS OF UNINTERRUPTED SLEEP BEFORE REPORTING FOR DUTY, CAN THE OSC REDUCE THE PROBABILITY OF HIGH FATIGUE LEVELS FROM DISRUPTED CIRCADIAN RHYTHMS THAT COULD ADVERSELY AFFECT THE PERFORMANCE OF CRITICAL PERSONNEL DURING A LAUNCH.
PENDING FURTHER INFORMATION CONCERNING CREW REST REQUIREMENT PROCEDURES FOR KEY LAUNCH PARTICIPANTS, THE BOARD CLASSIFIES A-93-100 "OPEN--ACCEPTABLE RESPONSE."