Stamped "Group 1 - Excluded from automatic downgrading and declassification"

T 0 P  S E C R E T   190237Z CITE CABLE 4732

PRIORITY [XXXXX]

OXCART LAW CODE

ATTN; [XXXXXXXXXXXXX] FROM: COL. PATTERSON

SUBJECT: SUMMARY OF ACCIDENT INVESTIGATION ANALYSIS

INVESTIGATION AND ANALYSIS:

1. WITNESS STATEMENTS, COCKPIT TAPE RECORDER DATA (DICTECT), RECORDED HF RADIO TRANSMISSIONS, AND SC&DM FLIGHT DATA MONITOR, WERE USED TO RECONSTRUCT THE FLIGHT PERFORMANCE AROUND BOTH NAVIGATION LEGS. INITIAL REVIEW INDICATED THAT THREE POSSIBILITIES EXISTED WHICH WOULD HAVE RESULTED IN FUEL DEPLETION NEAR THE POINT OF FLAME OUT.

A FULL FUEL OFFLOAD WAS NOT OBTAINED DURING THE AIR REFUELING PRECEEDING THE LAST NAVIGATION LEG. HAD THE PILOT DISREGARDED ALL BRIEFED FUEL MINIMUMS AND EXTENDED THE FLIGHT PROFILE BEYOND THE POINT OF SAFE RETURN, FUEL QUANTITIES REMAINING DURING THE DESCENT TO LAND WOULD HAVE APPROXIMATED THOSE REPORTED BY HF RADIO PRIOR TO FLAMEOUT. HOWEVER, THE COCKPIT TAPE RECORDER AND HF RADIO TRANSMISSIONS SHOW THAT INDICATED FUEL REMAINING OVER CHECK POINTS WAS ESSENTIALLY AS PROGRAMMED AT THE PLANNED TURNING POINT. THE PILOT WAS USING A REDUCED POWER CLIMB AND CRUISE PROCEDURE WHICH DURING PREVIOUS TESTS HAS REDUCED FUEL CONSUMPTION BY THE APPROXIMATE AMOUNT SHORT AFTER REFUELING. THEREFORE IT IS ENTIRELY POSSIBLE THAT INDICATED FUEL RESERVES WERE AT SPECIFIED MINIMUMS BY THE TIME HE REACHED THE TURN AND THE POSSIBILITY THAT HE KNOWINGLY DISREGARDED BRIEFED MINIMUMS WAS NOT SUBSTANTIATED BY DATA RECORDED.

A RAPID FUEL LEAK WHICH OCCURRED AFTER THE LAST PLANNED CHECK POINT FOR DIVERSION TO A SUITABLE ALTERNATE COULD HAVE RESULTED IN SIPHONING ALL THE REMAINING FUEL FROM ONE OF THE TANKS. THIS WOULD ACCOUNT FOR THE NEAR NORMAL FUEL CONSUMPTION DURING DESCENT AFTER THE DEFECTIVE TANK CONTENTS HAD EMPTIED BUT WOULD NOT HAVE EXPLAINED SIMILAR SUDDEN LOSS OF FUEL DURING APPROACH TO THE TANKER FOR REFUELING AFTER THE PREVIOUS CRUISE PROFILE. A FUEL LEAK OF SUCH PROPORTIONS WOULD HAVE BEEN READILY APPARENT TO THE TANKER CREW AND CHASE PILOT DURING REFUELING. THE TWO SUDDEN DROPS IN FUEL QUANTITY APPARENTLY OCCURRED WITH APPROXIMATELY THE SAME AMOUNT INDICATED ON THE GUAGE AND WERE TOO SIMILAR TO BE IGNORED. ALL POSSIBILITIES OF INCREASING FUEL CONSUMPTION DURING APPROACH TO THE TANKER SUCH AS THE USE OF AFTERBURNER WERE CONSIDERED, BUT THE HIGH RATE OF INDICATED FUEL DEPLETION COULD NOT BE EXPLAINED WITHOUT A MALFUNCTION OF SOME TYPE.

THE POSSIBILITY OF A GROSS FUEL QUANTITY GAUGE ERROR WHICH DISAPPEARS WHEN THE TANK, CONTAINING A FAULTY FUEL PROBE EMPTIES, WAS THOROUGHLY INVESTIGATED. TANKS THEEE AND FIVE EMPTY AT ABOUT THE FUEL QUANTITY WHERE THE SUDDEN DECREASE OCCURRED. TESTS WERE CONDUCTED WHICH INDICATE THAT THIS POSSISILITY DOES EXIST. BOTH FLIGHT PROFILES WERE RECONSTRUCTED WITH THE ASSUMPTION THAT THE ACTUAL FUEL QUANTITY ON BOARD THE AIRCRAFT WAS BETWEEN THREE AND FOUR THOUSAND POUNDS LESS THAN INDICATED AFTER BOTH REFUELINGS. APPLYING THIS ASSUMPTION, THE AMOUNT OF FUEL OFFLOADED AND THE REPORTED QUANTITIES REMAINING AT VARIOUS POINTS ALONG THE ROUTE ASSUME A LOGICAL SEQUENCE. THE BOARD REACHED THE CONCLUSION THAT THE MOST PROBABLE CAUSE OF FUEL DEPLETION RESULTED FROM A FAULTY QUANTITY INDICATING SYSTEM AND THAT THE ERROR RAPIDLY DECREASES SUBSEQUENT TO AN INDICATED FUEL REMAINING OF 14000 POUNDS.

2. EXAMINATION OF THE WRECKAGE REVEALED COMPLETE DISINTEGRATION UPON IMPACT. THE AIRCRAFT WAS INTACT IMMEDIATELY PRIOR TO IMPACT WITH THE EXCEPTION OF A LOWER WING FILLET AND THE CANOPY AND SEAT. THERE WAS NO INFLIGHT FIRE OR EXPLOSION. ALL BURNING WAS INDICATIVE OF POST IMPACT FIRE. DURING EJECTION SEQUENCE THE CANOPY SEPARATED FROM THE AIRCRAFT IN A NORMAL MANNER AND IMPACTED APPROXIMATELY [Excised by TM] MILES EAST OF THE WRECKAGE. ANALYSIS OF THE DICTECT, SC&DM AND FLIGHT RECORDER TAPES WAS DIFFICULT BECAUSE OF DAMAGE SUSTAINED AT IMPACT, THE OVER SHOULDER CAMERAS WERE MISSING FROM THE CANOPY, MAINTENANCE FORMS AND RECORDS WERE REVIEWED AND NO DISCREPANCIES WERE NOTED. DUE TO DISINTEGRATION OF THE AIRCRAFT AND COMPONENTS, INTEGRITY OF SYSTEMS COULD N0T BE SPECIFICALLY DETERMINED; HOWEVER, INVESTIGATION REVEALED NO STRUCTURAL, ENGINE OR FLIGHT CONTROL FAILURE PRIOR TO FLAME OUT AND/OR GROUND IMPACT.

3. DETAILED EXAMINATION AT THE SITE OF THE PILOT/SEAT IMPACT AREA ESTABLISHED THAT THE PILOT HAD NOT SEPARATED COMPLETELY FROM THE SEAT AND WAS FATALLY INJURED AT TIME OF IMPACT, SUBSEQUENT INVESTIGATION OF THE RECOVERED EJECTION SYSTEM COMPONENTS REVEALED THAT ALL SYSTEMS FUNCTIONED NORMALLY TO THE POINT OF MAN/SEAT SEPARATION. ANALYSIS OF THE COMPONENTS OF THE LAP BELT RELEASE MECHANISM AND TESTS CONDUCTED TO SIMULATE SEPARATION CONDITIONS, COULD NOT ABSOLUTELY ESTABLISH A SINGLE PRIMARY CAUSE FOR THE FAILURE OF MAN/SEAT SEPARATION, HOWEVER, IT WAS DETERMINED THAT A NUMBER OF POSSIBLE CAUSES FOR THE FAILURE OF THE MAN TO SEPARATE FROM THE SEAT COULD BE DEDUCED. FIRST, THE LAP BELT RELEASE MECHANISM COULD HAVE BEEN BOUND BY EXCESSIVE TENSION OR SIDE-LOADING ON THE LAP BELT AT THE TIME OF AUTOMATIC LAP BELT FIRING. SECOND, THE INTRUSION OF A FOREIGN OBJECT INTO THE LAP BELT RELEASE HOUSING COULD HAVE PREVENTED THE RELEASE FUNCTION. THIRD, THE DROGUE PARACHUTE PACK COULD HAVE BEEN JAMMED INTO THE HEADREST SPACER EXTENSION RESTRICTING PARACHUTE TRAVEL FROM UNDER THE HEADREST. FINALLY, ANY COMBINATION OF TWO OR MORE CONDITIONS THAT WOULD PROVIDE TENSION TO THE LAP BELT OR SHOULDER HARNESS DISENGAGEMENT FROM THE LAP BELT COULD HAVE CAUSED FAILURE OF THE PILOT TO SEPARATE FROM THE SEAT. THE PILOT COULD HAVE FAILED TO MANUALLY RELEASE THE LAP BELT DUE TO EXCESSIVE SEAT GYRATION, VISUAL RESTRICTIONS AND/OR OBSTRUCTIONS IN THE VICINITY OF THE LAP BELT MANUAL RELEASE LEVER WITHIN THE BRIEF TIME SPAN AVAILABLE BEFORE IMPACT WITH THE GROUND.

FINDINGS:

1. PRIMARY CAUSE:  THE PRIMARY CAUSE OF THIS ACCIDENT WAS FUEL DEPLETION FROM AN UNDETERMINED CAUSE. THE MOST PROBABLE CAUSE WAS A FUEL GAUGING ERROR RESULTING IN A HIGHER THAN ACTUAL INDICATED FUEL QUANTITY READ1NG.

2. CONTRIBUTING CAUSES:  PILOT FACTOR IN THAT AT THE TIME HE REPORTED 7500 POUNDS FUEL REMAINING, HE COULD HAVE DIVERTED TO ALBUQUERQUE.

3.ADDITIONAL FINDINGS:

• A. THE LOCATION OF THE DICTET RECORDER AND THE CONSTRUCTION OF THE SC&DM TAPE CASSETTE DOES NOT AFFORD ADEQUATE PROTECTION.
• B. THE PILOT WAS QUALIFIED AND PROPERLY BRIEFED TO CONDUCT THE MISSION.
• C. CONTROL TOWER AND THE SC&DM TAPE DID NOT HAVE AN ACCURATE TIME HACK WITH WWV.
• D. DURING THE SECOND REFUELING THE CHASE AIRCRAFT REFUELED FIRST AND TOOK 4000 POUNDS OF FUEL WHICH IF AVAILABLE TO THE PRIMARY AIRCRAFT WOULD PROBABLY HAVE ENABLED THE AIRCRAFT TO RETURN TO HOME BASE.
• E. PRECISE METHOD OF DETERMINING FUEL QUANTITY IN THE TANKS DURING GROUND FUELING DOES NOT EXIST.
• F. FUEL QUANTITY CALIBRATION PROCEDURES ARE NOT OPTIMIZED IN THAT THE CALIBRATION IS NOT MADE IN THE SEQUENCE THE FUEL IS USED.
• G. CHANGING OF A FUEL PROBE COULD CHANGE SYSTEM CALIBRATION SIGNIFICANTLY.
• H. THAT THE PRIMARY CAUSE FOR THE FAILURE OF THE PILOT TO CLEANLY SEPARATE FROM THE SEAT COULD NOT BE DETERMINED.
• I. THE MOST PROBABLE CAUSES FOR THE PILOT FAILING TO SEPARATE FROM THE SEAT WERE:
  • 1. FAILURE OP THE LAP BELT TO PELEASE DUE TO BINDING OR A FOREIGN OBJECT INTRUSION INTO THE RELEASE MECHANISM HOUSING.
  • 2. MAN-SEAT SEPARATOR ACTUATED PUSHING THE MAN AND CHUTE PACK UPWARD AND THE SEAT KIT FORWARD. THE CHUTE PACK JAMMED AGAINST THE HEADREST SPACER EXTENSION AND WITH CONSTANT PRESSURE BY THE SEPARATOR BELTS, THE PILOT COULD NOT SEPARATE FROM THE SEAT.

• A. CONSIDER THE RELOCATION OF THE DICTET RECORDER IN THE CANOPY.
• B. EXPLORE THE POSSIDILITIES OF MAKING THE SC&DM TAPE CASSETTE CRASH PROOF.
• C. ESTABLISH A REQUIREMENT TO DEFUEL AIRCRAFT AFTER EACH FLIGHT COMPARING THE FUEL INDICATOR QUANTITY TO ACTUAL OFF LOADED FUEL QUANTITY. AN ALLOWABLE DIFFERENCE LIMIT SHOULD BE ESTABLISHED.
• D. ON ALL GROUND FUELINGS THE AIRCRAFT SHOULD BE FILLED FROM A ZERO-FUEL CONDITION AND THEN OFF LOADED TO DESIRED FUEL QUANTITY. TOLERANCES MUST BE ESTABLISHED FOR DIFFERENCE IN INDICATOR AND TANKER READINGS, BOTH AT THE FULL AND OFF LOAD POINTS.
• E. FUEL TANK DIP STICK CAPABILITY SHOULD BE PROVIDED.
• F. A REQUIREMENT FOR FUEL SYSTEM CALIBRATION SHOULD BE ESTABLISHED WHEN ANY MAJOR COMPONENT, SUCH AS A PROBE, IS CHANGED.
• G. FUEL SYSTEM QUANTITY CALIBRATION PROCEDURES SHOULD BE AMENDED TO CONDUCT THE CALIBRATION IN THE SEQUENCE THE FUEL IS USED FROM THE TANKS.
• H. THE DICTECT BE REDESIGNED TO ALLOW A BREAK BETWEEN EACH CONVERSATION.
• I. THE LAST POINT AT WHICH THE PILOT HAS THE CAPABILITY TO DIVERT TO A SUITABLE ALTERNATE SHOULD BE IDENTIFIED ON ROUTE MAPS.
• J. LOCAL PROCEDURES BE PUBLISHED FOR TRAINING REFUELING MISSIONS THAT:
  • 1. THE TANKER WILL HAVE REQUIRED AND SCHEDULED FUEL ABOARD PLUS 10,000 POUNDS, CONDITIONS PERMITTING.
  • 2. CHASE MISSIONS ARE SCHEDULED SO THAT NO POSSIBILITY OF INTERFERENCE WITH REFUELING OF THE PRIMARY RECEIVER OCCURS.
• K. THAT THE HEADREST SPACER BE IMMEDIATELY REMOVED FROM ALL AIRCRAFT.
• L. THAT THE UNDERSIDE SURFACE OF THE HEADREST RAMP AND THE TOP SURFACE OF THE DROGUE PARACHUTE PACK BE PROVIDED A SMOOTH INTERFACE.
• M. THAT THE ROTARY ACTUATOR (MAN/SEAT SEPARATOR) STRAPS BE REPOSITIONED TO PROVIDE MAXIMUM FORWARD THRUST TO THE MAN/PARACHUTE MASS AND THE EIGHT NUTS AND BOLTS ON THE FRONT OF THE SEAT SECURING THE ROTARY ACTUATOR STRAPS BE REVERESED.
• N. THAT THE LAP BELT AUTOMATIC RELEASE MECHANISM BE REWORKED TO PREVENT TENSION OR SIDE LOAD BINDING OF THE PAWL LATCH LEVER AND A READILY ACCESSIBLE MANUAL LAP BELT RELEASE LEVER BE DEVELOPED.
• O. THAT THE SHOULDER HARNESS LOOPS BE SEWN TO PREVENT SLIPPING OVER THE AUTOMATIC LAP BELT LATCH LEVER HOUSING.
• P. THAT THE DEVELOPMENT OF EMERGENCY FACE PLATE HEATER AND THE PROTECTIVE COVER FOR THE OXYGEN CONTROLLER ASSEMBLY BE EXPEDITED.
• Q. THAT A D-RING CABLE CUTTER BE INSTALLED.
• R. THAT ALL FUTURE MODIFICATIONS TO THE EJECTION SYSTEM RECEIVE THOROUGH INVESTIGATION AND QUALIFICATION PRIOR TO ISSUANCE OF TCTO KITS OR SERVICE BULLETINS.

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