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Safety Recommendation Details

Safety Recommendation A-90-170
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: ANALYZE THE DISPERSION PATTERN, FRAGMENT SIZE AND ENERGY LEVEL OF RELEASED ENGINE ROTATING PARTS FROM THE JULY 19, 1989, SIOUX CITY, IOWA, DC-10 ACCIDENT AND INCLUDE THE RESULTS OF THIS ANALYSIS, AND ANY OTHER PERIPHERAL DATA AVAILABLE, IN A REVISION OF AC 20-128 FOR FUTURE AIRCRAFT CERTIFICATION.
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: 8/26/1997
Addressee(s) and Addressee Status: FAA (Closed - Acceptable Action)
Keyword(s):

Safety Recommendation History
From: NTSB
To: FAA
Date: 8/26/1997
Response: A-90-170 ASKED THE FEDERAL AVIATION ADMINISTRATION (FAA) TO ANALYZE THE DISPERSION PATTERN, FRAGMENT SIZE, AND ENERGY LEVEL OF RELEASED ENGINE ROTATING PARTS FROM THE JULY 19, 1989, SIOUX CITY, IOWA, DC-10 ACCIDENT AND INCLUDE THE RESULTS OF THIS ANALYSIS, AND ANY OTHER PERIPHERAL DATA AVAILABLE, IN A REVISION OF ADVISORY CIRCULAR (AC) 20-128 FOR FUTURE AIRCRAFT CERTIFICATION. BASED ON THE FAA'S ACTIONS, THE BOARD CLASSIFIES A-90-170 "CLOSED--ACCEPTABLE ACTION."

From: FAA
To: NTSB
Date: 6/19/1997
Response: THE FAA AGREED WITH THE INTENT OF THIS RECOMMENDATION AND ON MARCH 25, 1997, ISSUED ADVISORY CIRCULAR (AC) 20-128A, DESIGN CONSIDERATIONS FOR MINIMIZING HAZARDS CAUSED BY UNCONTAINED TURBINE ENGINE AND AUXILIARY POWER UNIT ROTOR FAILURE. THIS AC SETS FORTH A METHOD OF COMPLIANCE WITH THE REQUIREMENTS OF 14 CODE OF FEDERAL REGULATIONS (CFR) 23.901(F), 23903(B)(1), AND 25.901 (D)(1) PERTAINING TO DESIGN PRECAUTIONS TAKEN TO MINIMIZE THE HAZARDS TO AN AIRPLANE IN THE EVENT OF UNCONTAINED ENGINE OR AUXILIARY POWER UNIT ROTOR FAILURES. THE GUIDANCE PROVIDED IN THE AC IS HARMONIZED WITH THE EUROPEAN JOINT AVIATION AUTHORITIES.

From: NTSB
To: FAA
Date: 7/12/1993
Response: THE BOARD NOTES THAT THE FAA HAS ASSIGNED THIS RECOMMENDATION TO THE INSTALLATION HARMONIZATION WORKING GROUP THAT DEALS WITH NONCONTAINED ENGINE FAILURE ISSUES. IT IS REVIEWING & REVISING AC 20-128 TO DEAL WITH NONCONTAINED ENGINE FAILURE ISSUES ARISING UNDER 14 CFR PART 20, 25, 27, 29, & 33. THE WORKING GROUP WILL PRESENT ITS RECOMMENDATIONS TO THE AVIATION RULEMAKING ADVISORY COMMITTEE THAT WILL DECIDE WHETHER TO ENDORSE THOSE RECOMMENDATIONS & FORWARD THEM TO THE FAA. BASED ON THIS INFO, A-90-170 IS CLASSIFIED AS "OPEN--ACCEPTABLE RESPONSE."

From: FAA
To: NTSB
Date: 4/22/1993
Response: THE FAA AGREES WITH THE INTENT OF THIS RECOMMENDATION. AT THE JOINT AVIATION AUTHORITIES-FAA HARMONIZATION CONFERENCE IN TORONTO, ONTARIO, CANADA, IN JUNE 1992, THE FAA AGREED TO CONSOLIDATE WITHIN THE AVIATION RULEMAKING ADVISORY COMMITTEE (ARAC) AN OBJECTIVE TO "HARMONIZE" THE JOINT AVIATION REGULATIONS AND THE FEDERAL AVIATION REGULATIONS, AS WELL AS CERTAIN ADVISORY AND GUIDANCE MATERIAL. CONSEQUENTLY, THE FAA ESTABLISHED WORKING GROUPS TO CONSIDER HARMONIZATION ISSUES, INCLUDING THE INSTALLATION HARMONIZATION WORKING GROUP. ONE OF THE TASKS ASSIGNED TO THIS WORKING GROUP DEALS WITH NONCONTAINED ENGINE FAILURE ISSUES. THE WORKING GROUP WAS DIRECTED TO REVIEW AND REVISE ADVISORY CIRCULAR 120-128 TO DEAL WITH NONCONTAINED ENGINE FAILURE ISSUES ARISING UNDER 14 CFR PARTS 23, 25, 27, 29, AND 33. THE WORKING GROUP WILL PRESENT ITS RECOMMENDATIONS TO THE ARAC DURING A SPECIAL MEETING ON TRANSPORT, GENERAL AND BUSINESS AIRPLANE, ROTORCRAFT, AND ENGINE ISSUES.. AT THAT TIME THE ARAC WILL DECIDE WHETHER OR NOT TO ENDORSE THOSE RECOMMENDATIONS AND FORWARD THEM TO THE FAA.

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

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