The National Transportation Safety Board has released its preliminary report on the investigation into a plane crash in Farmington that killed four people and injured four others earlier this month.
The plane, a Cessna 560, was heading from Robertson Field Airport in Plainville to Dare County Regional Airport in Manteo, North Carolina when it crashed into the Trumpf production facility on Hyde Road in Farmington on Sept. 2 just before 10 a.m.
A pilot from Bristol, a pilot from Danbury, and a couple from Boston were killed.
The two pilots who died in the crash were William O’Leary, 55, of Bristol, Connecticut, and Mark Morrow, 57, of Danbury.
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The two passengers were 33-year-old Courtney Haviland, and 31-year-old William Shrauner, a husband and wife from Boston, Massachusetts.
The couple both worked as doctors in Boston, Shrauner at Brigham and Women's Hospital and Haviland at MassGeneral Hospital for Children.
The report says the cockpit, cabin, and wings were nearly consumed by fire after the crash and the parking brake handle in the cockpit and the valve that it controlled were both in the brake set position.
According to the NTSB report, one witness reported that the airplane hit a powerline pole, causing a small explosion near the right engine, then there was a shower of sparks before the witness lost sight of the plane when it was behind trees.
Witnesses told investigators that the airplane was going slower than they had seen during previous takeoffs and there was a puff of blue smoke from the backside of the airplane.
The flight data recorder showed the plane's acceleration values on the runway prior to the crash were lower than its two previous takeoffs, according to the NTSB report.
One witness reported that the nose landing gear was still on the ground as the airplane passed a taxiway intersection near the mid-point of the runway and he said to a friend that something was wrong.
NTSB investigators also said marks from the main landing gear went past the end of the runway and onto a grassy area.
Investigators found no anomalies with any of the airplane’s primary or secondary flight control surfaces.
In a Facebook post, the Trumpf company said two employees were injured because of the crash. Police said the injuries were not life-threatening and all of the other employees have been accounted for.
The NTSB report says one person on the ground sustained serious injuries and three people sustained minor injuries.