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Safety Recommendation Details

Safety Recommendation A-91-084
Details
Synopsis: ON JUNE 13, 1991, UNITED AIRLINES (UAL) MAINTENANCE PERSONNEL WERE UNABLE TO ELECTRICALLY OPEN THE AFT CARGO DOOR ON A BOEING 747-222B, N152UA, AT JOHN F. KENNEDY AIRPORT (JFK), JAMAICA, NEW YORK. THE AIRPLANE WAS ONE OF TWO USED EXCLUSIVELY ON NONSTOP FLIGHTS BETWEEN NARITA, JAPAN, & JFK. THIS PARTICULAR AIRPLANE HAD ACCUMULATED 19,053 HOURS AND 1,547 CYCLES AT THE TIME OF THE OCCURRENCE.
Recommendation: THE NTSB RECOMMENDS THAT THE FEDERAL AVIATION ADMINISTRATION: EVALUATE THE DESIGN, INSTALLATION, AND OPERATION OF THE FORWARD CARGO DOOR FLEXIBLE CONDUITS ON BOEING 747 AIRPLANES SO EQUIPPED AND ISSUE, IF WARRANTED, AN AIRWORTHINESS DIRECTIVE FOR INSPECTION AND REPAIR OF THE FLEXIBLE CONDUIT AND UNDERLYING WIRING BUNDLE, SIMILAR TO THE PROVISIONS RECOMMENDED IN A-91-83.
Original recommendation transmittal letter: PDF
Overall Status: Closed - Reconsidered
Mode: Aviation
Location: HONOLULU, HI, United States
Is Reiterated: No
Is Hazmat: No
Is NPRM: No
Accident #: DCA89MA027
Accident Reports: Explosive Decompression - Loss of Cargo Door in Flight, United Airlines Flight 811 Boeing 747-122, N4713U
Report #: None
Accident Date: 2/24/1989
Issue Date: 8/28/1991
Date Closed: 11/8/1993
Addressee(s) and Addressee Status: FAA (Closed - Reconsidered)
Keyword(s):

Safety Recommendation History
From: NTSB
To: FAA
Date: 11/8/1993
Response: THE BOARD FURTHER RECOMMENDED THAT WIRES WITH DAMAGED INSULATION BE REPAIRED BEFORE FURTHER SERVICE. DAMAGE TO THE FLEXIBLE CONDUIT, CONDUIT SUPPORT BRACKET, AND STANDOFF PIN SHOULD RESULT IN AN IMMEDIATE REPLACEMENT OF THE CONDUIT AS WELL AS THE DAMAGED PARTS. THE INSPECTION SHOULD BE REPEATED AT AN APPROPRIATE CYCLIC INTERVAL. THE BOARD THEN ASKED, IN SAFETY RECOMMENDATION A-91-84, THAT THE FAA EVALUATE THE DESIGN, INSTALLATION, AND OPERATION OF THE FORWARD CARGO DOOOR FLEXIBLE CONDUITS ON BOEING 747 AIRPLANES SO EQUIPPED AND ISSUE, IF WARRANTED, AN AIRWORTHINESS DIRECTIVE FOR INSPECTION AND REPAIR OF THE FLEXIBLE CONDUIT AND UNDERLYING WIRING BUNDLE, SIMILAR TO THE PROVISIONS RECOMMENDED IN RECOMMENDATION A-91-83. BASED ON THE LEVEL OF REDUNDANCY THAT NOW EXISTS TO PREVENT INADVERTENT DOOR OPENING IN FLIGHT, THE BOARD HAS CLASSIFIED RECOMMENDATIONS A-91-83 AND -84 AS "CLOSED--RECONSIDERED." THE BOARD WILL CLOSELY MONITOR INCIDENTS RELATED TO THE UNCOMMANDED OPENING OF CARGO DOORS ON 747 AIRPLANES TO FURTHER DOCUMENT THIS POSITION.

From: FAA
To: NTSB
Date: 4/5/1993
Response: THE FAA AGREES WITH THE INTENT OF THE RECOMMENDATION AND ISSUED AN NPRM. THE NPRM WAS WITHDRAWN, HOWEVER, BECAUSE THE FAA AND BOEING FOUND THAT THE LEVEL OF REDUNDANCY PROTECTION IN THE CARGO DOORS IS SUFFICIENT TO PRECLUDE THE NECESSITY OF PERFORMING A PERIODIC INSPECTION OF THE WIRE BUNDLES. THE FAA IS CONVINCED THAT AD 90-09-06 IS SUFFICIENT TO MAINTAIN THE DOOR OPENING/LOCKING DEVICES. FURTHER, DISCUSSION WITH FAA STAFF HAS REVEALED THAT THE FAA IS ALSO CONCERNED THAT SAFETY PROBLEMS COULD ACTUALLY BE CREATED DURING THE SUGGESTED INTRUSIVE INSPECTIONS THAT MIGHT BE MORE HAZARDOUS THAN THE CHAFFED WIRES SHORTED CIRCUITS.

From: NTSB
To: FAA
Date: 11/27/1991
Response: These recommendations were issued as a result of the Board's investigation of an incident in which the rear cargo door on a Boeing 747-222B initially would not open electrically and then opened electrically without activation of the door open switches. Your letter indicates that the Federal Aviation Administration agrees with the intent of these recommendations and is considering the issuance of a notice of proposed rulemaking to address these issues. The Board urges the FAA to move expeditiously on the recommendations. Pending receipt of additional information concerning the action to be taken by the Federal Aviation Administration, the Safety Board is classifying Safety Recommendations A-91-83 and -84 as "Open--Acceptable Action."

From: FAA
To: NTSB
Date: 11/1/1991
Response: THE FEDERAL AVIATION ADMINISTRATION AGREES WITH THE INTENT OF THESE RECOMMENDATIONS AND IS CONSIDERING THE ISSUANCE OF A NOTICE OF PROPOSED RULEMAKING TO ADDRESS THESE ISSUES.