NTSB Identification: ANC02FA023A
Scheduled 14 CFR operation of ALASKA AIRLINES, INC.
Accident occurred Sunday, March 17, 2002 in Anchorage, AK
Probable Cause Approval Date: 06/15/2004
Aircraft: McDonnell Douglas MD-82, registration: N935AS
Injuries: 149 Uninjured.
NTSB investigators either traveled in support of this investigation or conducted a significant amount of investigative work without any travel, and used data obtained from various sources to prepare this aircraft accident report.
A McDonnell Douglas MD-82 airplane sustained substantial damage during an on-ground collision with a McDonnell Douglas MD-11, as the MD-82 was being pushed back from the gate area, and while the MD-11 was taxiing to parking. The MD-11 was not damaged. There was heavy snowfall with reduced visibility at the time of the accident, and the airport ramp around the gate area had an estimated 8 inches of loose snow. The captain of the MD-82 reported that prior to pushback from the gate, he was advised by the ATCT ground controller to "remain clear of taxiway Kilo during pushback from the gate." The captain informed the tug driver of the ground controller's instructions, and the tug driver acknowledged receipt of the instructions. Taxiway Kilo is adjacent to, and south of, the airport ramp area utilized by the MD-82 operator. As the pushback proceeded, the tug driver noticed the MD-11 moving westbound on Taxiway Kilo, behind the tail of the MD-82, and he stopped the pushback. A ground-marshaling attendant stationed on the east side of the MD-82's wing (right wing), proceeded to the rear of the airplane to ensure adequate clearance between the tail of the MD-82, and the right wing of the MD-11. The tug driver said that he observed the ground-marshaling attendant on his left, closest to the tail of the MD-82, using his (red) flashlight wand, to signal him to move the parked MD-82 away from Taxiway Kilo, towards the gate. The tug driver said that just after observing the ground-marshaling attendant's visual instructions, the taxiing MD-11's right wing struck the tail of the parked MD-82. The captain of the MD-11 stated that while taxiing slowly westbound on Taxiway Kilo, with the recessed green taxiway centerline lights easily visible through the accumulation of snow, he kept the nose wheel over the centerline of the taxiway. As his airplane approached the tail of the stopped MD-82, the relief captain, seated in the right seat, along with an additional (non-flying) first officer, stood up from their seats to attempt to visually assess the clearance between the MD-11's right wingtip and the MD-82's tail. The MD-11 captain added that there was a heavy accumulation of snow covering the right side window, which limited the relief captain's and first officer's views. He said at that point, the MD-11 crew turned their attention to the MD-82's ground handling staff who were outfitted with lighted (red) flashlight wands. The captain reported that he did not see a stop or emergency signal from any of the ground-marshaling attendants. Subsequently, the right winglet of the taxiing MD-11 collided with the upper portion of the MD-82's rudder assembly. At the time of the accident, there was a Douglas DC-8 following the accident MD-11 to parking. The DC-8's flight crew reported reduced visibility due to heavy snowfall, and blowing snow from the MD-11's jet blast. They reported that the recessed green taxiway centerline lights were visible through the 3 to 4 inches of loose snow on the taxiway, immediately in front of their airplane, but became obscured after several hundred feet in front of their airplane. The DC-8 first officer wrote, in part: "As we approached the [MD-82], I was concerned about their proximity to our taxiway, although I feel they had not entered it. Or, if they had, they had already been tugged back." During an interview with NTSB IIC, the ground-marshaling attendant for the MD-82 was asked if he attempted to provide the flight crew of the taxiing MD-11, prior to the collision, the signal for an emergency stop (the crisscrossed lighted (red) flashlight wands). His response was "no."
The National Transportation Safety Board determines the probable cause(s) of this accident to be: The failure of the flight crew of the other airplane (MD-11) to maintain clearance while taxiing and the MD-82 ground-marshaling personnel’s failure to follow procedures/directives when they did not display an emergency stop signal to the flight crew of the other airplane. Factors contributing to the accident were heavy snow showers and snow-covered terrain. Full narrative available
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