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Safety Recommendation Details

Safety Recommendation A-94-009
Details
Synopsis: ON MARCH 31, 1993, THE NO.2 ENGINE AND ENGINE PYLON SEPARATED FROM JAPAN AIRLINES, INC., FLIGHT 46E, A BOEING 747-121, THAT HAD BEEN WET-LEASED FROM EVERGREEN INTERNATIONAL AIRLINES, INC., SHORTLY AFTER DEPARTURE FROM ANCHORAGE INTERNATIONAL AIRPORT (ANC), ANCHORAGE, ALASKA. THE ACCIDENT OCCURRED ABOUT 1234 ALASKA STANDARD TIME. THE FLIGHT WAS A SCHEDULED CARGO FLIGHT FROM ANCHORAGE TO CHICAGO-O'HARE INTERNATIONAL AIRPORT, CHICAGO, ILLINOIS. ON BOARD THE AIRPLANE WERE THE FLIGHTCREW, CONSISTING OF THE CAPTAIN, THE FIRST OFFICER, AND THE SECOND OFFICER, AND TWO NONREVENUE COMPANY EMPLOYEES. THE AIRPLANE WAS SUBSTANTIALLY DAMAGED DURING THE SEPARATION OF THE ENGINE. NO ONE ON BOARD THE AIRPLANE OR ON THE GROUND WAS INJURED AS A RESULT TO THE ACCIDENT.
Recommendation: THE NTSB RECOMMENDS THAT THE FEDERAL AVIATION ADMINISTRATION: ISSUE AN AIRWORTHINESS DIRECTIVE TO REQUIRE THAT THE MIDSPAR FUSE PINS ON BOEING 747 AIRPLANES BE REMOVED AND INSPECTED FOR DEFORMATION FOLLOWING AN ENCOUNTER WITH SEVERE TURBULENCE IN WHICH THE AIRPLANE EXPERIENCES LARGE VARIATIONS IN ROLL AND YAW ATTITUDE, AS PROVIDED IN THE BOEING COMMERICAL AIRPLANE COMPANY'S PROPOSED MODIFICATIONS TO THE BOEING 747 MAINTENANCE MANUAL, SECTIONS 5-51-03 AND 5-51-06.
Original recommendation transmittal letter: PDF
Overall Status: Closed - Acceptable Action
Mode: Aviation
Location: ANCHORAGE, AK, United States
Is Reiterated: No
Is Hazmat: No
Is NPRM: No
Accident #: DCA93MA033
Accident Reports: In-Flight Engine Separation Japan Airlines, Inc., Flight 46E Boeing 747-121, N473EV
Report #: AAR-93-06
Accident Date: 3/31/1993
Issue Date: 1/31/1994
Date Closed: 3/21/1996
Addressee(s) and Addressee Status: FAA (Closed - Acceptable Action)
Keyword(s): Weather, Turbulence

Safety Recommendation History
From: NTSB
To: FAA
Date: 3/21/1996
Response: THE BOARD FINDS THAT AD 92-24-51, WHICH REQUIRES A REPETITIVE INSPECTION OF THE MIDSPAR FUSE PINS AT INTERVALS NOT TO EXCEED 5OO LANDINGS, IN COMBINATION WITH THE CHANGES TO THE B-747 MAINTENANCE MANUAL, MEETS THE INTENT OF THIS RECOMMENDATION. THEREFORE, A-94-9 IS CLASSIFIED "CLOSED--ACCEPTABLE ACTION."

From: FAA
To: NTSB
Date: 1/26/1996
Response: FAA USSUED AIRWORTHINESS DIRECTIVE 92-24-51 WHICH REQUIRES A REPETITIVE INSPECTION OF THE EXISTING MID SPAR FUSE PINS AT INTERVALS NOT TO EXCEED 500 LANDINGS. ADDITIONALLY, BOEING HAS REVISED SECTION 5-51-03 & 5-51-06 OF THE BOEING 747 INSPECTION PROGRAM FOR AIRPLANES WHICH ENCOUNTER SEVERE TURBULENCE.

From: NTSB
To: FAA
Date: 6/7/1994
Response: THE BOARD NOTES THAT THE BOEING-PROPOSED MODIFICATIONS TO SECTIONS 5-51-03 & 5-51-06 WILL BE INCORPORATED INTO THE PROCEDURES USED BY MAINTENANCE PERSONNEL, & THAT EXISTING AD 92-214-51 REQUIRES A REPETITIVE INSPECTION OF THE MIDSPAR FUSE PINS AT INTERVALS NOT TO EXCEED 500 LANDINGS. THE BOARD AGREES THAT THE COMBINATION OF THE CHANGES TO THE MAINTENANCE MANUAL & THE EXISTING AD MEET BOARD'S INTENT IN ISSUING THIS RECOMMENDATION. THEREFORE, PENDING INCORPORATION OF THE PROPOSED CHANGES TO SECTIONS 5-51-03 & 5-51-06 INTO THE BOEING 747 MAINTENANCE MANUAL, A-94-9 IS CLASSIFIED "OPEN--ACCEPTABLE RESPONSE."

From: FAA
To: NTSB
Date: 4/20/1994
Response: THE AIRCRAFT MAINTENANCE MANUAL HAS SPECIFIC INSPECTION PROCEDURES ESTABLISHED FOR INCIDENTS SUCH AS HARD LANDING OR AN ENCOUNTER WITH SEVERE TURBULENCE. THE INDUSTRY EXPERIENCE HAS DEMONSTRATED CLEARLY THAT THE EXISTING PROCEDURES ARE FOLLOWED BY FLIGHTCREWS WITH RESPECT TO REPORTING SEVERE TURBULENCE ENCOUNTERS & BY MAINTENANCE PERSONNEL WITH RESPECT TO ADHERING TO THE ESTABLISHED INSPECTION PROCEDURES. WITH RESPECT TO THE BOEING MODEL 747 MAINTENANCE MANUAL, THE INSPECTION PROCEDURES FOR AIRPLANES WHICH ENCOUNTER SEVERE TURBULENCE ARE EFFECTIVE. THE INTENT OF THESE INSPECTIONS IS TO FIND OVERLOADED & DEFORMED FUSE PINS & OTHER PYLON STRUCTURE & TO TAKE CORRECTIVE ACTION TO PREVENT OPERATING AN AIRPLANE WITH A DAMAGED PYLON.