NTSB Identification: NYC95IA043.
The docket is stored in the Docket Management System (DMS). Please contact Records Management Division
Scheduled 14 CFR (D.B.A. TRANS WORLD AIRLINES )
Incident occurred Sunday, December 18, 1994 in JAMAICA, NY
Probable Cause Approval Date: 10/13/1995
Aircraft: BOEING 747-131, registration: N53116
Injuries: 189 Uninjured.
NTSB investigators used data provided by various sources and may not have traveled in support of this investigation to prepare this aircraft incident report.
DURING LANDING ROLL, THE LEFT MAIN GEAR OUTER CYLINDER SEPARATED. METALLURGICAL EXAMINATION REVEALED A PRE-EXISTING FATIGUE CRACK IN THE SCHRADER VALVE HOLE. THE HOLE, INCLUDING THE FATIGUE REGION, CONTAINED A LAYER OF NICKEL APPLIED DURING OVERHAUL AS A MEANS OF RESTORING THE ORIGINAL TOLERANCES OF THE PART. THE CRACKING INITIATED FROM A 0.009-INCH-DEEP GOUGE OR FILING MARK IN THE NICKEL LAYER. BECAUSE OF THE PRESENCE OF THIS AND SIMILAR NEARBY MARKS, THE CORNER FAILED TO COMPLY WITH THE OVERHAUL REQUIREMENT OF A RADIUS PF 0.6 TO 0.9 INCH AT THE FATIGUE INITIATION LOCATION. ALSO, A BEVEL FOUND IN THE NICKEL LAYER AT THIS CORNER, DID NOT COMPLY WITH THE CORNER REQUIREMENT. THE CYLINDER HAD 82,131 HOURS OF TOTAL TIME AND 14,951 CYCLES, AND WAS LAST OVERHAULED AND RETURNED TO SERVICE SEPTEMBER 30, 1988. ALSO, GOUGES, AND FILING MARKS WERE DETERMINED TO BE THE SOURCE OF THE CRACK.
The National Transportation Safety Board determines the probable cause(s) of this incident to be: Improper maintenance overhaul which resulted in a fatigue crack. Full narrative available
Index for Dec1994 | Index of months