NTSB Press Release

National Transportation Safety Board
Office of Public Affairs


UPDATE ON INVESTIGATION OF UNITED AIRLINES FLIGHT 42 DUAL ENGINE ROLL BACK

March 14, 2001

Washington DC - On Sunday, March 4, 2001 a United Airlines Boeing 767 departing from Maui, Hawaii experienced a dual engine roll back. The airplane diverted to Kona, Hawaii and made a normal landing. Upon landing in Kona, the aircraft was examined by representatives from the Federal Aviation Administration and United personnel. The aircraft was later flown to a United maintenance facility in San Francisco for further examination.

There were no injuries as a result of this incident. The aircraft's Cockpit Voice Recorder (CVR) and Flight Data Recorder (FDR) were delivered to the National Transportation Safety Board laboratory in Washington D.C. The CVR contained no information relevant to this incident. The initial readout of the FDR indicates that, while climbing through 29,000 feet, the right engine experienced a reduction in power to below idle but did not completely stop operating. About 20 seconds later, the left engine experienced a similar reduction in power.

The reduction of power occurred as the crew attempted to rectify an imbalance in the fuel load. Approximately 20 seconds after the power reduction in the second engine, the FDR stopped recording data for a period of time no greater than half a minute. When the FDR began recording again, the power of both engines was increasing. The engines returned to normal power shortly thereafter; data shows that neither engine experienced a total loss of power.

Based on current information, there is no indication that the airplane, its engines, or systems malfunctioned. Since the engine roll back occurred during a fuel transfer procedure, United Airlines, Boeing, and the NTSB are evaluating operational procedures and the operating characteristics of the engines and fuel system.

NTSB Office of Public Affairs: (202) 314-6100

 

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The National Transportation Safety Board (NTSB) is an independent federal agency charged with determining the probable cause
of transportation accidents, promoting transportation safety, and assisting victims of transportation accidents and their families.