What happened
On July 14, 2024, at approximately 11:31 JST, an Alexander Schleicher ASK13 glider, registration JA246 69, was conducting a solo flight training mission at the Kitami District Temporary Operation Site in Hokkaido, Japan. The flight was part of the trainee pilot's requirements to obtain a private pilot license.
After being aero-towed and releasing the tow rope at an altitude of roughly 2,100 feet, the pilot transitioned to the south traffic pattern. During the approach to Runway 10, the aircraft maintained an airspeed of approximately 100 km/h. Upon reaching the touchdown target, the glider bounced and floated about one meter above the runway surface. The pilot failed to execute the necessary recovery maneuvers, causing the aircraft's angle of attack to increase. This resulted in a hard landing approximately 310 meters from the runway threshold. The impact caused the trainee pilot to sustain a fractured spine.
The investigation
The Japan Transport Safety Board (JTSB) examined the flight history, meteorological conditions, and the pilot's training progress. At the time of the accident, wind speeds were light, ranging from 1 to 2 m/s, providing a nearly direct headwind. The investigation noted that while the aircraft's weight and center of gravity were within limits, and the glider sustained no structural damage, the pilot's speed control was inadequate.
Investigators reviewed the trainee's recent training sessions, noting that on the day of the accident, the pilot had completed two on-board training sessions with an instructor. While the instructor had cleared the pilot for solo flight, previous observations indicated that the pilot struggled with maintaining appropriate approach speeds and sufficient flare maneuvers.
Findings
- The primary cause of the hard landing was the pilot's failure to perform a recovery maneuver after the aircraft bounced and floated.
- The pilot's inability to control the aircraft's speed and the insufficient flare maneuver contributed to the increased angle of attack and subsequent impact.
- The trainee pilot's lack of stable flight skills and experience played a significant role, as the pilot became unsettled by the unexpected bounce and failed to stabilize the descent.
- The instructor's certification of the trainee for solo flight occurred despite ongoing issues with speed control and approach stability noted during earlier training sessions that day.