What happened
A commercial certificated pilot was conducting a landing operation on a beach surface. The aircraft, equipped with specialized tundra tires designed for soft or uneven terrain, touched down and began its landing roll. During this phase of ground movement, the airplane encountered an unseen irregularity or bump in the terrain that was not visible to the pilot prior to impact.
The interaction with this hidden obstacle caused the tailwheel to bounce violently. This sudden vertical displacement resulted in a loss of control geometry, leading the nose of the aircraft to pitch forward and strike the ground. The event concluded with the airplane coming to rest in a nose-over attitude.
The investigation
Post-accident examination of the airframe revealed significant structural damage consistent with a nose-over impact. The fuselage sustained substantial deformation. Additionally, the wing lift struts were damaged, likely due to the abnormal loading forces transmitted through the landing gear during the bounce and subsequent nose-down attitude.
The propeller and rudder also incurred damage. The condition of the tundra tires and the nature of the terrain bump suggest that the initial cause was related to ground contact with an unexpected obstacle rather than a mechanical failure of the aircraft systems prior to impact.
Findings
The primary factor in this accident was the encounter with an unseen bump in the beach terrain during the landing roll. This external hazard caused the tailwheel to bounce, which directly led to the nose-over incident. The structural damage to the fuselage, wing lift struts, propeller, and rudder confirms the severity of the nose-down impact. No injuries were reported among the occupants.