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Safety Recommendation Details

Safety Recommendation A-90-169
Details
Synopsis: ON JULY 19, 1989, AT 1516, A DC-10-10, N1819U, OPERATED BY UNITED AIRLINES (UAL) AS FLIGHT 232, EXPERIENCED A CATASTROPHIC FAILURE OF THE NO. 2 TAIL-MOUNTED ENGINE DURING CRUISE FLIGHT. THE SEPARATION, FRAGMENTATION AND FORCEFUL DISCHARGE OF STAGE 1 FAN ROTOR ASSEMBLY PARTS FROM THE NO. 2 ENGINE LED TO THE LOSS OF THE THREE HYDRAULIC SYSTEMS THAT POWERED THE AIRPLANE'S FLIGHT CONTROLS. THE FLIGHTCREW EXPERIENCED SEVERE DIFFICULTIES CONTROLLING THE AIRPLANE, WHICH SUBSEQUENTLY CRASHED DURING AN ATTEMPTED LANDING AT SIOUX GATEWAY AIRPORT, IOWA. THERE WERE 285 PASSENGERS AND 11 CREWMEMBERS ONBOARD. ONE FLIGHT ATTENDANT AND 110 PASSENGERS WERE FATALLY INJURED.
Recommendation: THE NTSB RECOMMENDS THAT THE FEDERAL AVIATION ADMINISTRATION: CONDUCT SYSTEM SAFETY REVIEWS OF CURRENTLY CERTIFICATED AIRCRAFT AS A RESULT OF THE LESSONS LEARNED FROM THE JULY 19, 1989, SIOUX CITY, IOWA, DC-10 ACCIDENT TO GIVE ALL POSSIBLE CONSIDERATION TO THE REDUNDANCY OF, AND PROTECTION FOR, POWER SOURCES FOR FLIGHT AND ENGINE CONTROLS.
Original recommendation transmittal letter: PDF
Overall Status: Closed - Acceptable Action
Mode: Aviation
Location: SIOUX CITY, IA, United States
Is Reiterated: No
Is Hazmat: No
Is NPRM: No
Accident #: DCA89MA063
Accident Reports: United Airlines Flight 232 McDonnell Douglas DC-10-10‚Äč
Report #: AAR-90-06
Accident Date: 7/19/1989
Issue Date: 12/14/1990
Date Closed: 4/8/1996
Addressee(s) and Addressee Status: FAA (Closed - Acceptable Action)
Keyword(s):

Safety Recommendation History
From: NTSB
To: FAA
Date: 4/8/1996
Response: THE BOARD NOTES THAT THE FAA HAS ADDRESSED A-90-169 THROUGH ITS SYSTEMS REVIEW TASK FORCE & SUBSEQUENT AIRWORTHINESS DIRECTIVES. THE SYSTEMS REVIEW TASK FORCE'S REPORT RECOMMENDED APPROPRIATE DESIGN CHANGES TO AFFORD PROTECTION FOR FLIGHT CONTROL SYSTEMS & THEIR POWER SOURCES. ADS BASED UPON THESE RECOMMENDATIONS WERE ISSUED FOR THE LOCKHEED L1011, BOEING 747/757/767, & MCDONNELL DOUGLAS DC-10 AIRPLANES. BECAUSE THESE ACTIONS FULFILL THE INTENT OF THE RECOMMENDATION, THE BOARD CLASSIFIES A-90-169 "CLOSED--ACCEPTABLE ACTION."

From: FAA
To: NTSB
Date: 1/17/1996
Response: THE FAA, IN A LETTER DATED 1/17/96, STATED THAT ITS SYSTEMS REVIEW TASK FORCE COMPLETED ITS FINAL REPORT THAT RECOMMENDED APPROPRIATE DESIGN CHANGES THAT AFFORD PROTECTION FOR FLIGHT CONTROL SYSTEMS & THEIR POWER SOURCES. ADS BASED UPON THESE RECOMMENDATIONS WERE ISSUED FOR THE LOCKHEED L1011, BOEING 747/757/767, & THE MCDONNELL DOUGLAS DC-10 AIRPLANES.

From: NTSB
To: FAA
Date: 11/30/1993
Response: THE BOARD NOTES THAT THE FAA'S SYSTEMS REVIEW TASK FORCE HAS COMPLETED ITS REPORT OF THE EXISTING FLIGHT CONTROL SYSTEM AND POWER SOURCE DESIGNS ON CURRENT TRANSPORT-CATEGORY AIRPLANES. THIS SUMMARY REPORT HAS BEEN SENT TO THE AVIATION RULEMAKING ADVISORY COMMITTEE'S FAA TRANSPORT AIRPLANE AND ENGINE SUBCOMMITTEE AND THE SYSTEMS REVIEW TASK FORCCE STEERING COMMITTEE. IT INCLUDES THE WORKING GROUP'S RECOMMENDATION, WHICH INCLUDE MANDATORY DESIGN CHANGES TO APPROPRIATE AIRPLANES. HOWEVER, THE SYSTEMS REVIEW TASK FORCE SUMMARY REPORT AND WORKING GROUP FINAL REPORTS DO NOT ADDESS PROTECTION FOR POWER SOURCE FOR ENGINE CONTROLS. WHILE THE BOARD AGREES THAT THE RELATED SERVICE HISTORY FOR EXISTING TRANSPORT-CATEGORY AIRPLANES WITH ELECTRONIC ENGINE CONTROLS IS EXCELLENT, IT BELIEVES THAT SUCH DESIGN SHOULD BE REVIEWED TO DETERMINE THE LEVEL OF PROTECTION IN THE EVENT OF CATASTROPHIC FAILURE OF AN ADJACENT ENGINE. PENDING THE FAA'S COMMITMENT TO ACT ON THIS RECOMMENDATION, THE BOARD CLASSIFIES RECOMMENDATION A-90-169 "OPEN--ACCEPTABLE RESPONSE."

From: FAA
To: NTSB
Date: 6/30/1993
Response: THE SYSTEMS REVIEW TASK FORCE HAS INVESTIGATED THE EXISTING FLIGHT CONTROL SYSTEM AND POWER SOURCE DESIGNS ON CURRENT TRANSPORT CATEGORY AIRPLANES TO DETERMINE IF ENHANCEMENTS ARE AVAILABLE OR CAN BE DESIGNED TO ACCOMPLISH THE GOALS OF THIS SAFETY ISSUE. FINAL REPORTS WERE COMPLETED FROM THE AIRBUS, BOEING, MCDONNELL DOUGLAS, CONTAINMENT, AND OTHER HAZARDS WORKING GROUPS. THESE STUDIES ADDRESSED THE DESIGN OF ALL AIRPLANES WITH FULLY POWERED FLIGHT CONTROL SYSTEMS. THE AIRBUS A320 AND THE BOEING 757 AIRPLANES WERE AMONG THOSE STUDIED. THE WORK BEING CONDUCTED BY THE LOCKHEED WORKING GROUP WAS DELAYED DUE TO RELOCATION OF THE L-1011 ENGINEERING GROUP FROM CALIFORNIA TO GEORGIA. THIS GROUP IS EXPECTED TO COMPLETE ITS REPORT SHORTLY. THE SUMMARY REPORT PREPARED BY THE SYSTEMS REVIEW TASK FORCE HAS BEEN COMPLETED AND SENT TO THE AVIATION RULEMAKING ADVISORY COMMITTEE'S FAA TRANSPORT AIRPLANE AND ENGINE SUBOMMITTEE AND THE SYSTEM REVIEW TASK FORCE STEERING COMMITTEE. THIS SUMMARY REPORT INCLUDES RECOMMENDATIONS FROM THE WORKING GROUP REPORTS WHICH INCLUDE MANDATORY DESIGN CHANGES TO APPROPRIATE AIRPLANES. THE SYSTEMS REVIEW TASK FORCE SUMMARY REPORT AND WORKING GROUP FINAL REPORTS DO NOT ADDRESS PROTECTION FOR POWER SOURCES FOR ENGINE CONTROLS. EXISTING CERTIFICATION RULES HAVE PROVIDED AN EXCELLENT SAFETY RECORD FOR EXISTING TRANSPORT CATEGORY.

From: NTSB
To: FAA
Date: 10/9/1991
Response:

From: FAA
To: NTSB
Date: 3/8/1991
Response: