ARMONK, N.Y. A June 2011 plane crash that claimed the lives of four people shortly after takeoff from Westchester County Airport was likely caused by the pilots decision to fly with a suspected mechanical deficiency, concluded the National Transportation Safety Board (NTSB).
Shortly after takeoff from runway 34, the pilot informed the air traffic controller that he needed to return to the airport and requested runway 16, said the report on the June 18 crash. The pilot declared an emergency but did not state the reason why.
The plane flew into trees and terrain about one mile from runway 16, in the wooded area behind MBIA Inc., where Keith Weiner, 63, Lisa Weiner, 51, Isabel Weiner, 14, and Lucy Walsh, 14, died on impact. The Manhattan residents were heading to Montauk, Long Island.
The resulting fire in the 350-foot wreckage site was put out by the Armonk Fire Department. The report states that the first identifiable point of impact was at the top of a 60-foot tall mature maple tree.
NTSB officials said that witnesses observed the pilot perform multiple engine run-ups before departing and that the engine initially idled rough. While five cylinders worked, there was one not functioning correctly.
Examination of the engine revealed that the No. 2 cylinder piston head exhibited severe thermal deterioration consistent with a pre-ignition or detonation event, said the report. The electrodes of the No. 2 cylinder spark plugs were fully imbedded with aluminum and appeared incapable of producing a spark.
The pilots decision to fly the final approach at a reduced power setting was another likely cause of the accident, the report said, along with the improper timing of the magneto(s) that resulted in a severe detonation event.
The full report goes into detail on the plane, flight history, weather, the autopsy report, and tests and research done on the aircraft. The report states that the pilot was certified and had more than 4,000 hours of flying experience.