NTSB Factual Report

On April 9, 2001, about 0800 eastern daylight time, a Boeing 767-200ER, N328AA, operated by American Airlines, Inc., as flight 1547, struck and substantially damaged a Boeing 737-832, N3731T, operated by Delta Airlines, Inc., as flight 1823, while taxiing for takeoff at General Edward Lawrence Logan International Airport (BOS), Boston, Massachusetts. The 2 flight crew members, 6 flight attendants, and 141 passengers on board flight 1547, destined for Orlando, Florida, and the 2 flight crew members, 4 flight attendants, and 116 passengers on board flight 1823, destined for Flushing, New York, were not injured. Instrument meteorological conditions prevailed, and an instrument flight rules flight plan had been filed for both flights, which were conducted under 14 CFR Part 121.

According to information received from a Federal Aviation Administration inspector, Delta flight 1823 was instructed by air traffic control (ATC) to "hold short" of runway 27, on taxiway "D-1," while it awaited takeoff clearance, and American flight 1547 was instructed to taxi to runway 27, via taxiway "D." While taxiing, the right wing tip of American flight 1547 struck and substantially damaged the left elevator and horizontal stabilizer of Delta flight 1823. The right wing of American flight 1547 sustained minor damage. Both airplanes then taxied to their respective gates without further incident.

The flight crew from Delta flight 1823 reported that the airplane had been holding short of the runway 27 hold line, with the parking brakes set, when they felt a "violent shudder." They then looked back and observed an American Airlines Boeing 767 taxiing past them on taxiway D.

The flight crew from American flight 1547 reported that the sun was creating a glare on the airplane's windscreen, and that they observed the Delta 737 holding short of runway 27 as they taxied on taxiway D. In a written statement, the captain said:

"...Although the aircraft was not all the way up to the hold short line, I felt there was more than adequate clearance to continue, and in fact moved slightly to the left of the taxiway centerline, away from the other aircraft, slowed down, and continued. A jolt/bump was felt by both of us...."

The cockpit voice recorder (CVR) from both airplanes were forwarded to the Safety Board's Vehicle Recorders Division for readout.

The CVR for flight 1547 contained non-pertinent audio information, which was recorded after the accident. The CVR for flight 1823 captured the accident approximately 1 hour, 40 minutes into the 2-hour recording. According to the CVR specialist's factual report, at 0801:13, BOS ATC cleared flight 1547 to taxi into position and hold on runway 27. At 0801:18, a rumbling sound lasting approximately 1.5 seconds was recorded by the cockpit area microphone, and was followed by exclamations from the cockpit crew and a flight attendant. The flight crew then notified BOS ATC, that an American Boeing 767 had dragged its wingtip through the tail of their airplane and requested the "crash crew." At 0804:40, the captain was recorded asking how far the airplane was from the hold short line; about five, six, or seven feet? The first officer responded in the affirmative.

According to a BOS airport diagram, taxiway D was located on the north side of, and parallel to runway 27. Taxiway D-1 extended at an angle to the northwest, from runway 27, to taxiway D. According to a Massachusetts Port Authority representative, the perpendicular distance between the taxiway D centerline and the runway 27 hold short line was 220 feet.

Dimensional data provided by the manufacturer revealed that the overall wingspan of a Boeing 767-200, and the overall length of a Boeing 737-800, was approximately 156 feet, 1 inch, and 124 feet, 9 inches, respectively.

The weather reported at BOS, at 0730, included a visibility of 2.5 statue miles in mist, and a broken ceiling of 600 feet.

NTSB Probable Cause

The Boeing 767 captain's misjudgment of the distance between his airplane and the stationary Boeing 737, which resulted in a ground collision. A factor was sunglare.