TWA Flight 159

Trans World Airlines (TWA) Flight 159 was a regularly scheduled passenger flight from New York to Los Angeles, California, with a stopover in Cincinnati/Northern Kentucky International Airport, Kentucky, that crashed after an aborted takeoff from Cincinnati on 6 November 1967. The Boeing 707 attempted to abort takeoff when the copilot became concerned that the aircraft had collided with a disabled DC-9 on the runway. The aircraft overran the runway, struck an embankment and caught fire. All 29 passengers and 7 crew escaped the aircraft, but one passenger died of his injuries four days later.

The NTSB concluded that the crash occurred due to the TWA flight crew's inability to successfully abort takeoff due to the speed of the aircraft, and that a runway overrun was unavoidable at the 707's speed. The disabled DC-9, a Delta Air Lines flight which had reported that it had cleared the runway when in fact it had not, was a contributing factor in the crash. The NTSB recommended that the FAA establish and publicize standards of safe clearance from runway edges for both aircraft and ground vehicles which also take into account the exhaust fumes of jet engines. The Board also recommended a reevaluation of training manuals and aircraft procedures in regards to abort procedures.

Flight history and crash

The aircraft was a Boeing 707 which had accumulated 26,319 airframe hours since its first flight in 1959.^[1] It was piloted by Captain Volney D. Matheny, 45, who had 18,753 hours of pilot time. The copilot was First Officer Ronald G. Reichardt, 26, with 1,629 total piloting hours, and the flight engineer was Robert D. Barron, 39, who had accumulated 11,182 hours as a flight engineer. The stewardesses were Janan Perkins, 21, Roswitha Neal, 25, Kathleen Fankhouser, 21, and Sara Muir, 25.^[2]

Flight 159 was a New York-Los Angeles flight with a stopover at Cincinnati/Northern Kentucky International Airport, Kentucky. As the aircraft approached Runway 27L, another flight, Delta Air Lines Flight 379 (DAL 379), a DC-9, was coming in for landing on the same runway. After landing, DAL 379 received permission to turn 180° to reach a passed intersection, but the DC-9 was unable to complete the turn, and ran off the paved runway. While most of the aircraft was stuck in the mud well away from the runway, the tail was only approximately 7 feet (2.1 m) from the edge.^[1][2]

When queried if his aircraft was clear of the runway, the captain of the Delta DC-9 replied, "Yeah, we're in the dirt though." Flight 159, which had taxied into position, was given clearance to depart at 6:41 pm EST. As Flight 159 sped down the runway, the Captain observed that the DC-9 was "[n]ot very . . far off the runway." As the Boeing passed, a pop and the sound of an engine losing power was heard in the cockpit. Thinking he had hit the DC-9, the co-pilot, who was in control of the aircraft, attempted to abort the takeoff.^[2]

The aircraft overran the runway, becoming airborne for 67 feet (20 m). The landing gear was sheared off, and the 707 slid on its underbelly 300 feet (91 m) to rest with its nose in a muddy embankment.^[2][3] The fuselage ruptured, and the structure of one wing failed during the crash.^[1] The right side wing of the plane caught fire as it left the runway.^[3] All 29 passengers and 7 crew members escaped the aircraft, with two passengers requiring hospitalization.^[3] The 707 was damaged beyond repair and regarded as a complete write off after the fire damaged right wing and broken fuselage.^[1]

Aftermath

The National Transportation Safety Board (NTSB) conducted the investigation and determined that the pop heard by the copilot had been a compressor stall in the number four engine that occurred due to the jet blast of the DC-9. The 707 had not, in fact, hit the other plane.^[2]

The TWA company manuals indicated aborting a takeoff at high speeds is dangerous, and should only be attempted if an actual engine failure occurs before V₁ speed and stopping distance is limited. "V₁" speed is the maximum speed at which the takeoff can be safely aborted; after V₁ speed is exceeded, the pilot must takeoff. The Captain of Flight 159 did not follow procedure and announce V₁ speed, so the copilot assumed that the aircraft had not yet reached that threshold and attempted to abort, when in reality it had substantially exceeded it. On a Boeing 707, the V₁ speed is 132 knots (244 km/h; 152 mph); Flight 159 achieved a peak speed of 145 knots (269 km/h; 167 mph).^[1][2]

The NTSB determined that neither Federal Aviation Administration (FAA) regulations nor the Terminal Air Traffic Control Procedures Manual defined the phrase "clear of the runway," and found that the pilots of each plane and the air traffic controller each had their own slightly different definition of the term. Though the tail of the Delta DC9 was several feet from the runway, the exhaust from its idling jet engines was being directed over the runway.^[2]

The majority opinion presented by the NTSB accident report determined that the cause of the accident was the TWA flight crew's inability to successfully abort takeoff procedures due to an excess of speed. It recommended revisions and expansions to airline abort procedures and new FAA regulations defining runway clearance and procedures, taking into account jet engine fumes. One NTSB member, Francis H. McAdams, dissented with the other four investigators and published a minority report stating the probable cause of the accident was the Delta crew's failure to adequately advise the tower of the proximity to the runway, and the tower's failure to request additional and precise information prior to clearing TWA 159 for takeoff.^[2]

The family of the deceased passenger received a $105,000 settlement from Delta Air Lines in civil court. TWA also sued Delta for the loss of the 707 for settlement of $2,216,000.^[4]

See also

• List of accidents and incidents involving airliners in the United States

References

External links

• NTSB accident brief CHI68A0043
• Accident photo