The 1967 Hendersonville mid-air collision occurred when a Piedmont AirlinesBoeing 727-22 and a twin-engine Cessna 310 collided on July 19, 1967 over Hendersonville, North Carolina, USA. Both aircraft were destroyed and all passengers and crew were killed, including John T. McNaughton, an advisor to Robert McNamara. The aircraft were both operating under instrument flight rules and in radio contact with the Asheville control tower, though on different frequencies. The accident investigation carried out in the aftermath of the crash was the first major investigation ever conducted by the newly created National Transportation Safety Board. A review of the investigation, conducted 39 years after the crash, upheld the original findings that had placed primary responsibility on the Cessna pilot.
Flight and crash
Piedmont Flight 22 took off from Asheville Regional Airport's runway 16 at 11:58 a.m. for a 35-minute IFR flight to Roanoke, Virginia. While the Boeing 727 was still on its takeoff roll, the pilot of the Cessna 310 N3121S reported "Two one Sierra just passed over the VOR, we're headed for the... for.. ah.. Asheville now." The approach controller then cleared the Cessna to descend and maintain 6,000 feet. At 11:59:44 the controller cleared Flight 22 to "... climb unrestricted to the VOR, report passing the VOR". He then cleared the Cessna for an approach to runway 16. The 727 was still climbing when the Cessna slammed into the plane just aft of the cockpit at an altitude of 6,132 feet, and disintegrated. Many witnesses reported the collision as sounding like a jet breaking the sound barrier. The 727 rolled onto its back and crashed vertically into a camp known as Camp Pinewood, exploding on impact.
Original investigation
This was the first major airline accident investigated by the NationalTransportation Safety Board, newly formed to replace the Civil Aeronautics Board. The NTSB's report placed the primary responsibility for the accident on the Cessna pilot, while citing air traffic control procedures as a contributing factor, and recommended a review of minimum pilot skill levels required for IFR flight.
Controversy and new investigation
In 2006, 39 years after the accident, the NTSB agreed to reopen the investigation to review possible irregularities identified by Paul Houle, a former traffic accident investigator with the United States Army and historian who spent several years studying the accident. Houle alleged the following problems with the NTSB's original investigation:
The original NTSB report omitted the fact that the Cessna pilot had properly reported his heading, which should have alerted air traffic control to a potential conflict between the two planes. The report claims that there was a four-second pause at that point, but the transcript shows no such pause.
The original NTSB report does not mention that there was a fire in a cockpit ashtray in the 727, which occupied the attention of the 727 crew for the 35 seconds before the collision.
The lead NTSB investigator had an apparent conflict of interest, since his brother was a vice president and director of Piedmont Airlines.
Houle also mentioned that, at the time, the newly formed NTSB was not fully independent of the Federal Aviation Administration, since both reported to the Department of Transportation. Houle claimed that these conflicts of interest led the NTSB to avoid citing either Piedmont or FAA controllers as the primary causes of the accident. In February 2007, the NTSB reported that it had upheld its original findings, re-confirming the probable cause it found in 1968 for the midair collision. In a letter to Houle, NTSB chairman Mark Rosenker said the board had voted 3–1 that his arguments were unsubstantiated.