TWA Flight 400 Crash Near Pittsburgh (N40403)

Flight Details and Departure Conditions TWA Flight 400 was a regularly scheduled service operating between Pittsburgh, Pennsylvania, and Newark, New Jersey, with intermediate stops at Harrisburg, Reading, and Allentown, Pennsylvania. The flight crew consisted of Captain Raymond F. McQuade, First Officer Harlan V. Jesperson, and Hostess Vary Jane Fanning. Before departure, the pilots received a briefing on en route weather and reviewed sequence and forecast reports. Despite generally good en route weather, the flight was dispatched to Newark on an Instrument Flight Rules (IFR) flight plan via airways, which was standard practice. At the time of departure, the aircraft's gross weight was 41,822 pounds, which was below both the certificated allowable takeoff gross weight of 44,900 pounds and TWA's internal limit of 43,650 pounds. The center of gravity was within prescribed limits. The scheduled departure time was 1915. The flight requested and received taxi clearance at 1916, was informed that the wind was calm, and was cleared to runway 23. Takeoff clearance was requested and granted at 1919. ## Accident Sequence Approximately one minute after takeoff clearance, tower personnel observed what appeared to be a normal takeoff and initial climb. This was immediately followed by a left turning descent, a crash, and an erupting fire just beyond the southwest boundary of the airport. Passengers attempted to extricate themselves from the wreckage through and ahead of the fire as best they could. Some passengers helped others, while a few were thrown out through tears and rents in the shattered fuselage. ## Emergency Response and Casualties Airport-based firefighting equipment was dispatched, but approximately 20 minutes elapsed before it reached the site due to the necessity of traversing circuitous country lanes. By the time the fire crews arrived, the conflagration had nearly consumed the wreckage, and it was quickly smothered. The accident resulted in the deaths of the stewardess and 21 passengers, while 14 other occupants were injured. The aircraft was totally destroyed. ## Probable Cause and Findings The Board determined that the probable cause of the accident was uncoordinated emergency action in the very short time available to the crew, which produced an airplane configuration with unsurmountable drag. Key findings included: - At the time of the first power reduction, the first officer saw the left engine zone 1 fire warning light come on and retarded the left throttle to a point where autofeathering was deactivated. - The first officer then reached for the left manual feathering button but was dissuaded from using it by the captain. The captain, not knowing that autofeathering was inoperative, attempted futilely to obtain it by pulling back the left mixture to idle cutoff. - This action did not comply with the emergency procedures prescribed by the carrier for powerplant fire or failure. - Although these were not the most desirable procedures, compliance without delay would have feathered the left propeller. - The windmilling left propeller, the extended landing gear, and the takeoff flaps produced sufficient drag to make the airplane lose altitude and strike the ground. - The cause of the fire warning was a failed exhaust connector clamp in the left engine, which triggered an adjacent fire detecting unit. - After the accident, the carrier revised its emergency procedures for powerplant fire or failure.