On November 27, 1982, a Boeing 707-323C (registration HK284) operated by Aerotal Ltda. was involved in an aviation accident near Miami, FL. Investigators recorded the probable cause as: Fatigue failure of the No. 15 first stage fan blade (PN 531601K) in the No. 4 engine, which occurred 3.2 hours after overhaul, leading to engine failure. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive.
Flight crew aborted takeoff after hearing a loud explosion; tower reported flames from the No. 4 engine. Investigation revealed engine failure due to fatigue of a first stage fan blade that occurred 3.2 hours after overhaul.
Event Description
During the takeoff roll, after reaching takeoff power, the flight crew heard a loud explosion and aborted the takeoff. While taxiing, air traffic control informed the crew that flames were emanating from the No. 4 engine. The crew stopped the aircraft and executed the engine fire procedures, after which airport fire fighters extinguished the fire.
Investigation Findings
Examination of the failed engine showed that the No. 4 engine had experienced an explosive failure, releasing high-energy engine parts that caused damage to the airframe and the No. 3 engine. Most rotating components forward of the 7th stage compressor disk assembly were released during the failure.
Further examination of the first stage compressor fan blades revealed that the No. 15 first stage fan blade, part number 531601K, had failed due to fatigue. This failure occurred 3.2 hours after the engine had been overhauled.
Probable cause
Fatigue failure of the No. 15 first stage fan blade (PN 531601K) in the No. 4 engine, which occurred 3.2 hours after overhaul, leading to engine failure.
