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Safety Recommendation Details

Safety Recommendation A-89-097
Details
Synopsis: THE NATIONAL TRANSPORTATION SAFETY BOARD'S INVESTIGATION OF THE UNITED AIRLINES DC-10 ACCIDENT AT SIOUX CITY, IOWA, ON JULY 19, 1989, IS CONTINUING. THE INVESTIGATION THUS FAR INDICATES THAT MOST OF THE FAN ROTOR ASSEMBLY SEPARATED FROM THE NO. 2 ENGINE IN FLIGHT. THE SEPARATION, FRAGMENTATION, AND FORCEFUL DISCHARGE OF FAN ROTOR PARTS SEVERED OR LOOSENED HYDRAULIC LINES ASSOCIATED WITH ALL THREE HYDRAULICS SYSTEMS, WHICH RESULTED IN THE LOSS OF ALL HYDAULIC SERVICES INCLUDING THOSE TO THE FLIGHT CONTROLS. FOLLOWING THE LOSS OF THE HYDRAULIC SERVICES, THE AIRPLANE COULD BE CONTROLLED ONLY BY THE FLIGHTCREW'S USE OF DIFFERENTIAL THRUST FROM THE NOS. 1 AND 3 ENGINES. THE AIRPLANE CRASHED DURING AN ATTEMPTED EMERGENCY LANDING AT SIOUX CITY. OF THE 296 PERSONS ON BOARD, 111 DIED FROM INJURIES RECEIVED IN THE CRASH, AND 185 PERSONS SURVIVED.
Recommendation: TO THE FEDERAL AVIATION ADMINISTRATION: Evaluate, because of similarities in design, manufacture, and maintenance, the need for a directed safety investigation of all general electric cf6-series turbine engines with the objectives of verifying the established life limits for rotating parts of the fan modules and establishing appropriate cyclic inspection requirements for these parts. (Superseded by A-90-090)
Original recommendation transmittal letter: PDF
Overall Status: Closed - Superseded
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: 8/17/1989
Date Closed: 6/18/1990
Addressee(s) and Addressee Status: FAA (Closed - Superseded)
Keyword(s):

Safety Recommendation History
From: NTSB
To: FAA
Date: 6/18/1990
Response: Per Green Sheet A-90-88 through -91: On August 17, 1989, the Safety Board issued Recommendations A-89-95, A-89-96, and A-89-97. These recommendations requested a directed safety study of the CF6-6 engine, issuance of an Airworthiness Directive to require inspections identified by the directed safety study, and an evaluation of the need for a directed safety study of all GEAE CF6 series engines. The Safety Board believes that Recommendations A-90-88, A-90-89, and A-90-90 (the first three recommendations in this letter) encompass these earlier recommendations, and the Safety Board is therefore classifying Recommendations A-89-95, A-89-96, and A-89-97 as "Closed--Superseded."

From: FAA
To: NTSB
Date: 4/6/1990
Response: The FAA agrees with this safety recommendation. Review of lifting methodology is, and continues to be, an ongoing FAA/GE process to determine if additional inspections/field actions are necessary. The FAA and GE are currently reviewing the applicability of the CF6-6D inspection program to other CF6 series engines.

From: NTSB
To: FAA
Date: 12/8/1989
Response: As you are aware, the Safety Board has just completed a 4-day hearing into the circumstances surrounding this accident, and the investigation in ongoing. For the present, therefore, we acknowledge the FAA's and GE's ongoing engineering evaluation and classify these safety recommendations as "Open--Acceptable Action."

From: FAA
To: NTSB
Date: 9/5/1989
Response: REVIEW OF LIFTING METHODOLOGY AND SUBSTANTIATION DATA IS, AND CONTINUES TO BE, AN ONGOING FAA/GENERAL ELECTRIC PROCESS. UPON CONCLUSION OF THIS CF6-6D INVESTIGATION, THE APPLICABILITY OF THE CORRECTIVE ACTION TO OTHER CF6-6D SERIES ENGINES WILL BE EVALUATED.