More Evidence Indicates Jet’s Flaps Were Retracted
A federal panel looking into the takeoff crash of a Delta Air Lines jetliner here Aug. 31 heard highly technical testimony Wednesday that reinforced evidence that the pilots failed to deploy the plane’s wing flaps properly.
The testimony, from a variety of aviation experts, indicated that:
--A mechanism that locks wing tip aileron controls on a Boeing 727 was found in the “flaps retracted” position after the crash.
--A bolt on the mid-wing “jack screw” that moves the flaps was found in the retracted position after the crash.
--Wind tunnel data for a Boeing 727 attempting a takeoff without flaps showed considerable similarity to the data generated by the actual flight of the plane that crashed. The wind tunnel data showed the plane would have had considerably more difficulty taking off with flaps retracted than with flaps properly deployed.
The National Transportation Safety Board disclosed earlier that the flaps, which provide extra lift on takeoff, were found in the retracted position after the crash. The lever used to deploy the flaps was also found in the retracted position.
Most of Wednesday’s testimony went unchallenged, but the Air Line Pilots’ Assn., which has been defending the cockpit crew’s actions and performance in the moments before the crash of Flight 1141, immediately disputed Wednesday’s remarks by Boeing Aircraft Co. expert Ronald J. Halvarson on wind tunnel data, saying the figures he cited were incomplete and possibly misleading.
The Boeing 727 jetliner slammed into the ground moments after takeoff from Dallas-Ft. Worth International Airport, killing 14 of the 108 aboard.
National Transportation Safety Board investigators say they are still far from determining what caused the big jet to crash..
Pilot Larry L. Davis, 49, co-pilot Carey W. Kirkland Jr., 37, and flight engineer Steven M. Judd, 31, all told the NTSB panel Tuesday that they were sure the flaps and slats were deployed prior to takeoff, although none of the three specifically remembered that being done. ALPA has suggested that the cockpit crew may have moved the lever correctly, but that because of a mechanical malfunction, only a portion of the flaps deployed.
