What happened
On November 16, 2015, a privately owned Beechcraft A36, registration JA3762, was conducting touch-and-go training at Sendai Airport. The flight was operated by a captain who was flying this specific aircraft type for the first time, accompanied by an experienced passenger acting as an observer.
During the flight, the pilot attempted to adjust the flaps to 10 degrees but failed to return the control handle to the stop position, causing the flaps to extend to the full down position. This unexpected change in pitch required the pilot to focus heavily on correcting the elevator trim. Simultaneously, the pilot was attempting to use a stopwatch to time the landing gear extension, but the watch was not functioning correctly.
As the aircraft entered the base leg, the passenger briefly took control of the aircraft after noticing a height discrepancy. During this period of high workload and distraction, the pilot failed to extend the landing gear. The aircraft subsequently touched down on runway 12 with the gear in the up position, resulting in a belly landing that caused substantial damage to the fuselage, engine exhaust pipes, propeller tips, and nose gear doors.
The investigation
The Japan Transport Safety Board (JTSB) examined the flight history, cockpit procedures, and the mechanical condition of the aircraft. The investigation focused on the pilot's lack of familiarity with the aircraft's specific systems, the breakdown in checklist usage, and the operational status of the landing gear warning system. Investigators also reviewed the cockpit environment, noting that the crew was managing multiple simultaneous tasks, including flap correction, trim adjustment, and air traffic control communications.
Findings
- The pilot attempted to operate an unfamiliar aircraft type without first conducting a proper ground familiarization or verifying the operation of the flap control switch.
- The crew failed to perform the required before-landing checklist, which would have confirmed the landing gear was in the down position.
- The pilot's attention was diverted by the need to correct the aircraft's pitch and altitude following the improper flap setting.
- The passenger was distracted by monitoring the flap position indicator and correcting the flight path.
- A functional defect in the landing gear warning system prevented the audible alarm from activating when the throttle was closed, which might have otherwise alerted the crew to the gear's status.