What happened
On June 29, 2017, a Beechcraft 58, registration JA5304, operated by School Judicial Organization KIMIGAFUCHI GAKUEN (Sojo University), performed a belly landing at Nagasaki Airport. The aircraft was conducting a training flight intended to promote a trainee to the rank of captain. During the flight, the crew was practicing touch-and-go landings and a short-field landing on runway 1s.
During the downwind leg of the approach, the instructor was providing detailed instructions to the trainee regarding landing techniques. As the aircraft transitioned to the final approach, the trainee focused heavily on controlling the aircraft and aiming for the touchdown point. Consequently, the trainee failed to execute the landing gear-down procedures and did not complete the required landing checklist. The instructor, satisfied with the trainee's stable aircraft control, was also less attentive to monitoring the trainee's procedural compliance.
As the aircraft approached the runway, the landing gear warning horn activated, but the crew did not acknowledge it. Upon touchdown, the aircraft's fuselage and propellers struck the runway surface. The aircraft deviated to the left and came to a stop on the runway. The incident resulted in substantial damage to the aircraft, including damage to the propellers, engine, nose, and fuselage.
The investigation
The JTSB investigation examined the flight records, communication between the aircraft and the tower, and the physical condition of the aircraft. Investigators reviewed the landing gear system, confirming that the mechanical components, including the safety switches, the landing gear handle's detention mechanism, and the warning horn, were all fully functional. The investigation also reviewed the university's Standard Training Procedure Manual and the flight crew's actions during the approach.
Findings
- The primary cause of the accident was the aircraft touching down without the landing gear being extended.
- The trainee was distracted by the complexities of the short-field landing procedure and the need to control the aircraft's path, leading to the omission of the gear-down procedure and the landing checklist.
- The instructor's attention was focused on the trainee's flight control performance rather than monitoring procedural compliance, which prevented the detection of the error.
- The crew's focus on the touchdown point caused them to overlook the landing gear warning horn activation.
Safety action
The university has updated its training guidelines to minimize instructional distractions during critical phases of flight, such as takeoff and landing. New procedures require instructors to confirm the completion of checklists and have amended the training manual to ensure that final gear-down confirmations at 200 ft AGL are strictly monitored.