A small jet that crashed into a building in Connecticut, killing four people earlier this month, was going slower than usual as it took off from an airport runway, while witnesses saw a puff of smoke and noticed the aircraft was having trouble gaining altitude, according to a preliminary investigation report released Tuesday.
The report by the National Transportation Safety Board also said the plane’s parking brake was found to be on, although it was not clear when it was activated.
The report did not say what may have caused the Sept. 2 crash in Farmington, which remains under investigation.
The twin-engine Cessna 560XL was to have flown from Robertson Airport in Plainville to Dare County Regional Airport in Manteo, North Carolina. But it crashed into a manufacturing building shortly after takeoff and burst into flames, authorities said.
Killed were a Boston couple who were both doctors, Courtney Haviland, 33, her husband, William Shrauner, 32, and the two pilots, William O’Leary, 55, of Bristol, and Mark Morrow, 57, of Danbury. Four people on the ground were injured, including one who was seriously hurt. Haviland and Shrauner left behind a toddler-age son, and Haviland was pregnant at the time of the crash, according to relatives.
As the twin-engine Cessna 560XL was accelerating on the runway at Robertson Airport in Plainville, one witness noticed it was going slower than usual, the report said. The flight data recorder showed it took the plane 17 seconds to accelerate from 20 knots to 100 knots, compared with 11.5 seconds and 12 seconds during its previous two flights, investigators said.
A witness saw a puff of blue-colored smoke from the jet’s rear, and another witness believed something was wrong because the nose landing gear was still on the ground near the mid-point of the runway, the report said.
A third witness saw the plane leave the runway in a level position and its nose pitched up, but it was not climbing, investigators said.
“The airplane then impacted a powerline pole, which caused a small explosion near the right engine followed by a shower of softball-size sparks,” the report said. “After hitting the pole, the noise of the engine went from normal sounding to a much more grinding, metallic sound.”
The jet then hit a grassy area next to the Trumpf Inc. manufacturing building, about 850 feet (259 meters) north of the utility pole. It then struck the building, causing a fire that consumed most of the aircraft, the report said.
Investigators who examined the plane after the crash noticed the parking brake was on, and skid marks were found on the runway. But the flight data recorder did not record the parking brake valve position, which was not monitored by the takeoff warning system, the report said.
NTSB officials say the final report, which would include the likely causes of the crash, could take a year or more to complete.