What happened
On April 9, 2018, a Korean Air Lines Boeing 737-900, registered HL7725, was performing a scheduled flight from Jeju International Airport to Kansai International Airport. During the approach to runway 06L, the aircraft encountered changing wind conditions. While the pilot flying (PF) had prepared for a landing with a tailwind, the actual wind conditions near the threshold were shifting.
As the aircraft approached the runway, the pilot reduced engine thrust to idle early in an attempt to manage the descent rate. However, the timing of the flare maneuver was delayed, and the aircraft's descent rate remained higher than anticipated. The aircraft touched down, but the impact resulted in a bounce. Fearing a hard second impact, the captain initiated a go-around maneuver.
During this go-around, the aircraft's pitch angle increased significantly. The aircraft's lower aft fuselage made contact with the runway, resulting in substantial damage, including scratch marks and a broken tail skid. There were 99 people on board, including 91 passengers and 8 crew members; no injuries were reported.
The investigation
The Japan Transport Safety Board (JTSB) examined flight data recorder (FDR) and cockpit voice recorder (CVR) data, air traffic control communications, and aircraft maintenance records. The investigation focused on the sequence of the landing, the effectiveness of the crew's coordination, and the specific pitch attitude of the aircraft during the transition from the bounce to the go-around. Investigators also reviewed the company's training manuals and the pilots' recent training records regarding bounced landing recovery.
Findings
- The pilot flying performed a large nose-up maneuver during the go-around because they were attempting to avoid a hard second touchdown.
- The aircraft's pitch angle exceeded the 8.2-degree threshold, which is the limit above which the lower aft fuselage is at risk of contacting the ground.
- The pilot monitoring (PM) intervened by pulling the control column to reduce the descent rate without providing a verbal call-out, which contributed to the lack of situational awareness regarding the increasing pitch.
- The initial landing flare was insufficient to compensate for the changing wind conditions and the early reduction of thrust.
- The primary cause of the tail strike was the excessive pitch angle achieved during the go-around following the bounced landing.