BOSTON (AP) — The pilots of a business jet that crashed in Massachusetts last year, killing a Philadelphia newspaper co-owner and six other people, did not perform a pre-flight check, failed to disengage a safety mechanism before attempting takeoff and reacted too late to a warning light, federal investigators said Wednesday.
The system the pilots forgot to disengage was supposed to keep the Gulfstream IV's throttle from being moved past 6 degrees. But it allowed the throttle to be moved about four times that, the National Transportation Safety Board said during a meeting in Washington to discuss the final report into the May 2014 crash at Hanscom Field in Bedford.
The pilot, co-pilot and flight attendant as well as four passengers, including Philadelphia Inquirer co-owner Lewis Katz, died. The passengers had been at an event at the home of historian and author Doris Kearns Goodwin.
By the time the pilots realized they would not be able to take off, tried to disengage the safety system and engaged the brakes, it was too late.
"Lock is on," pilot Bauke "Mike" De Vries said several times as the jet sped down the runway, according to the cockpit voice recorder. "I can't stop it," he said several seconds before impact.
The jet overran the runway, traveled across a grassy area and crashed into a ravine before almost immediately bursting into flames, the NTSB said.
The pilots, with thousands of hours of flight experience each and several years of working together, engaged a device called a gust lock upon landing in Massachusetts. The lock prevents wind damage when the plane is parked by immobilizing its flight control system.
But they never disengaged the lock when they prepared for takeoff about six hours later.
"Despite their experience, the pilots mad two key errors and neglected to release the gust lock and perform a flight control check," NTSD member William Bramble said. "The flight crew's neglect to release the gust lock was an unintentional error of omission."
The cockpit voice recorder indicated that the crew did not call for any checklist or talk about checklist items during the takeoff attempt.
The investigation found that the pilots almost never conducted pre-flight checks, described by investigators as a "consistent pattern of procedural noncompliance."
When the gust lock system is engaged, it is supposed to restrict the movement of the throttle so the plane cannot take off, but it failed to do so.
The plane's manufacturer, Gulfstream Aerospace Corp., said in a statement Wednesday that is has notified pilots of the importance of performing thorough pre-flight checks, and is working with the Federal Aviation Administration to modify the gust lock system on its jets.
Gulfstream has previously said the crash was due to the pilots' failure to conduct a pre-flight check.
In addition to the pilot and Katz, the others who died in the crash were co-pilot James McDowell, of Georgetown, Delaware; flight attendant Teresa Benhoff, of Easton, Maryland, Anne Leeds, a 74-year-old retired preschool teacher he invited on the trip just that day; Marcella Dalsey, the director of Katz's son's foundation; and Susan Asbell, 67, the wife of a former New Jersey county prosecutor.
The roughly 100-page final report will be posted on the NTSB's website with two weeks.