What happened
During the landing phase on runway 31R, a 4,274-hour airline transport pilot lost control of the aircraft while touchdown occurred on a runway measuring 7,752 feet in length and 150 feet in width. The aircraft drifted off the right side of the runway during the landing roll. Just prior to touchdown, tower reports indicated winds from 250 degrees at 27 knots, with gusts reaching 38 knots.
The investigation
A review of the flight data recorder (FDR) and cockpit voice recorder (CVR) provided technical insights into the landing sequence. Data revealed that for the first ten seconds following touchdown, the number 3 brake received more pressure than the number 1 brake. Additionally, during the four seconds that thrust reversers were in use, the number 2 engine was operated at a higher N1 than the number 1 engine.
Findings
The investigation determined that the operator had calculated the crosswind component using tabular data rather than a graph. When utilizing the graph for calculation, the crosswind component was approximately 33 knots. According to the Airplane Flight Manual, the maximum demonstrated crosswind for this aircraft is 30 knots.