What happened
On April 10, 2019, at approximately 20:40 EDT, an American Airlines Airbus A321, registration N114NN, was performing a scheduled flight from John F. Kennedy International Airport (JFK) to Los Angeles International Airport (LAX). During the takeoff roll on runway 31L, the aircraft experienced a significant left roll as it reached rotation speed.
As the aircraft rotated, the left wingtip struck the ground and a runway distance marker. The impact caused damage to the left wingtip sharklet, left aileron, left outboard flap, and the left outboard slat. Despite the impact, the flight crew successfully completed the takeoff and returned to JFK 2ability 28 minutes later. There were no injuries among the 110 occupants on board.
At the time of the accident, the weather consisted of night visual meteorological conditions with a crosswind component of approximately 14 to 17 knots.
The investigation
Investigators analyzed data from the digital flight data recorder (DFDR) and the cockpit voice recorder (CVR). The DFDR showed that during the takeoff roll, the captain applied left rudder to counter the right crosswind. As the aircraft accelerated to 156 knots, the captain's left rudder input increased from 8° to 25° within a 1.5-second period. This caused the aircraft's heading to deviate to 290°, which was 25° left of the runway centerline.
As the nose gear lifted off, the aircraft began to roll to the left, reaching a maximum roll angle of 37°. Airbus performed a handling qualities analysis using an engineering simulator, which confirmed that the aircraft's response matched the recorded flight data. The simulation demonstrated that the left roll was a direct result of the rudder input and that the aircraft's flight control systems were functioning normally.
American Airlines also conducted a comparative study of over 270,000 company takeoffs. The study found that while many flights experienced higher crosswinds, this specific flight had the longest duration of rudder application and the highest maximum rudder deflection in the analyzed dataset.
Findings
- The aircraft's left wingtip struck a runway distance marker, with a portion of the marker's support structure becoming lodged in the wingtip.
- The left wing sustained a permanent upward deflection, leading to the aircraft being retired from service.
- The captain's left rudder pedal input was excessive and unnecessary for the prevailing crosswind conditions.