(NECN: Peter Howe, Boston) - Stressing that it was still a preliminary report, the National Transportation Safety Board said Friday it found evidence of a possible mechanical problem with the equivalent of a parking brake for the Gulfstream IV jet that crashed and killed Philadelphia Inquirer co-owner Lewis Katz and six others at Hanscom Field in Bedford May 31.
But the NTSB also said it found no evidence that pilots conducted the kind of fundamental pre-flight check of their controls that they should have – and which could well have alerted them to a problem with the “gust lock” if that was a key factor that caused the jet to fail to get airborne, run off the runway and crash and burn in a gully, killing Katz, three of his friends, and both pilots and a flight attendant.
“The key piece of information that I saw in that preliminary report was the fact that the pilot failed to run a checklist,’’ aviation safety expert John Goglia said in an interview Friday. He served for nine years as a member of the NTSB, the first member of the board to hold a Federal Aviation Administration aircraft mechanic’s certificate. Goglia is a former Professor of Aviation Science and Director of the Center for Integrated Emergency Management at Saint Louis University’s Parks College of Engineering, Aviation and Technology.
In the NTSB report, which you can find here http://go.usa.gov/8hXd, investigators wrote, in part, “Review of FDR” or flight data recorder/”black box” information “did not reveal any movement consistent with a flight control check prior to the commencement of the takeoff roll." Goglia said that’s a standard thing pilots are taught to do before every single takeoff, turning the control wheel right and left, moving the control column or “yoke” forward and back, testing the rudder pedal movements on both sides, and other checks.
The NTSB also said black-box data “revealed the elevator control surface position during the taxi and takeoff was consistent with its position if the gust lock was engaged." The gust lock, deployed to protect a plane when it is parked on the ground, is roughly analogous to a parking brake for a car and in the case of a jet, freezes the plane’s elevator and flaps in positions that prevent the plane from getting airborne. When investigators combed the wreckage, they discovered the “gust lock handle, located on the right side of the control pedestal, was found in the forward (OFF) position, and the elevator gust lock latch was found not engaged.’’
Two possibilities this suggests are that there was a mechanical problem between the gust lock handle and the lock itself, so that moving the handle to the off position failed to release the lock, or that the pilots had begun to taxi and take off with the gust lock on and while moving tried to shut it off as they also deployed “thrust reversers” and wheel brakes to try to stop the plane from crashing.
“He may have forgotten the gust lock,’’ Goglia said, “but the bigger issue is, he didn't run the checklist, so it immediately makes him suspect for being a problem.’’
However, Boston attorney Peter Black, a partner with Meehan, Boyle, Black & Bogdanow P.C., an expert in aviation litigation who was a U.S. Navy pilot in Vietnam and business jet pilot before becoming an attorney, said after reviewing the NTSB report, “There are a lot of questions that need to be answered, and the preliminary report, I think, just makes more questions.’’
For Black, what doesn’t make sense is that in addition to freezing the elevator and flaps in a position that would have prevented the plane from getting airborne, the gust lock also should have held the idle speed of the jet engines at a very low level – and yet, the NTSB report said the Gulfstream IV was moving as fast as 165 knots, or close to 190 m.p.h., while racing down the runway, and was still moving about 115 m.p.h. when it crashed and burned past the end of Hanscom’s Runway 11.
“If the gust lock was engaged, if things were functioning properly, they never should have been able to advance the engine’’ to anything close to takeoff speed, “so I think at this point there's still a question as to what happened out there.’’
“If the gust lock was engaged, as I understand it, there was a mechanical lock that should have prevented the throttles from being advanced, so if it were engaged, even though the crew wouldn’t have had the control movement they also wouldn’t have been able to add power to take off. They would have been sitting at the end of the runway saying: ‘Something’s wrong,’ ‘’ Black said.
Goglia said he agrees that there are questions that still need to be answered about just what if anything was malfunctioning with the plane’s gust lock. But he said it appeared the most important takeaway lesson is one drilled into pilots during training: Just don’t ever, ever, ever skip the pre-flight controls check.
Had it been run on that plane on the night of May 31, Goglia said, any gust lock problem would have been “a non-event. It would have been found and rectified before he left.’’
With videographer Daniel J. Ferrigan
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