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Safety Recommendation Details

Safety Recommendation A-94-010
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: REVIEW THE SERVICE EXPERIENCE OF OTHER TYPES OF AIRPLANES TO DETERMINE IF SIMILAR INSPECTIONS OF THE ENGINE MOUNT STRUCTURES SHOULD BE CONDUCTED FOLLOWING ENCOUNTERS WITH SEVERE TURBULENCE IN WHICH THE AIRPLANE EXPERIENCES LARGE VARIATIONS IN ROLL AND YAW ATTITUDE.
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: 4/21/1996
Addressee(s) and Addressee Status: FAA (Closed - Acceptable Action)
Keyword(s): Weather, Turbulence

Safety Recommendation History
From: FAA
To: NTSB
Date: 1/26/1996
Response: THE FAA HAS COMPLETED ITS REVIEW OF THE SERVICE EXPERIENCE OF BOEING 707, 737 757, & 767 SERIES AIRPLANES; MCDONNELL DOUGLAS DC-8, DC-10, & MD-11 SERIES AIRPLANES,; LOCKHEED L1011 SERIES AIRPLANES, AIRBUS A300, A310 A320 SERIES AIRPLANES; & BRITISH AEROSPACE BAE-146 SERIES AIRPLANES TO DETERMINE IF INSPECTIONS OF THE ENGINE MOUNT/PYLON STRUCTURES SHOULD BE CONDUCTED FOLLOWING ENCOUNTERS WITH SEVERE TURBULENCE IN WHICH THE AIRPLANE EXPERIENCE LARGE VARIATIONS IN ROLL & YAW ATTITUDE. THE FAA'S REVIEW SHOWED NO RECORD OF PERMANENT DEFORMATIONS. OF THE ENGINE MOUNT STRUCTURE DUE TO SEVERE TURBULENCE. BASED ON RESULTS OF THE REVIEW, THE FAA CONCLUDES THAT INSPECTION REQUIREMENTS IN THE PRESENT MAINTENANCE PROCEDURES ARE SUFFICENT & THAT NO ADDITIONAL INSPECTION REQUIREMENTS ARE WARRANTED. I CONSIDER THE FAA'S ACTION TO BE COMPLETED ON THIS RECOMMENDATION, & I PLAN NO FURTHER ACTION.

From: NTSB
To: FAA
Date: 6/7/1994
Response: IN RESPONSE TO THIS RECOMMENDATION, THE FAA COMPLETED A REVIEW OF THE OPERATING EXPERIENCE OF THE OTHER MODELS OF BOEING AIRPLANES & THE MCDONNELL DOUGLAS MODELS DC-8, DC-10, & MD-11 TO DETERMINE IF THE ENGINE MOUNT/PYLON STRUCTURES SHOULD BE INSPECTED FOLLOWING ENCOUNTERS WITH SEVERE TURBULENCE IN WHICH THE AIRPLANE ENCOUNTERS LARGE VARIATIONS IN ROLL & YAW ATTITUDE. THAT REVIEW DETERMINED THAT THERE WAS INSUFFICIENT JUSTIFICATION FOR ANY ADDITIONAL ACTION REGARDING THESE AIRPLANES. HOWEVER, PENDING THE FAA'S REVIEW OF THE OPERATING EXPERIENCE OF OTHER AIRCRAFT, A-94-10 IS CLASSIFIED "OPEN--ACCEPTABLE RESPONSE."

From: FAA
To: NTSB
Date: 4/20/1994
Response: THE FAA HAS CONDUCTED A REVIEW OF THE SERVICE EXPERIENCE OF MCDONNELL DOUGLAS MODELS DC-8, DC-10, & MD-11 AIRPLANES TO DETERMINE IF INSPECTIONS OF THE ENGINE MOUNT/PYLON STRUCTURES SHOULD BE CONDUCTED FOLLOWING ENCOUNTERS WITH SEVERE TURBULENCE IN WHICH THE AIRPLANE EXPERIENCES LARGE VARIATIONS IN ROLL & YAW ATTITUDE. A REVIEW OF THE FAA'S SERVICE DIFFICULTY REPORT DATA BASE & THE MANUFACTURER'S PRODUCT SUPPORT SERVICE RECORDS SHOWED THAT THERE HAS BEEN ONLY ONE INCIDENT, ON 12/9/92, OF A DC-8 PYLON SEPARATION DUE TO OVERLOAD CAUSED BY SEVERE TURBULENCE DURING FLIGHT. HOWEVER, THE INVESTIGATION OF THAT INCIDENT HAS BEEN INCONCLUSIVE DUE TO THE LACK OF INFO REGARDING KEY FLIGHT PARAMETERS OBTAINED FROM THE FLIGHT DATA RECORDER. THERE IS NO PROVIOUS RECORD OF A SIMILAR INCIDENT ON ANY MCDONNELL DOUGLAS AIRPLANE.