What happened
The aircraft, N-number not provided, was chartered to retrieve salvage gear from a burned hovercraft that had run aground approximately one mile south of Chinitna Bay. Upon arrival at the site, the pilot reported that two passengers prepared the equipment for loading while he manually held the seaplane off the beach to prevent damage to the floats. Once the gear was loaded, a passenger assisted in holding the aircraft steady.
After loading was complete, the pilot taxied out and initiated a takeoff run toward the south. The aircraft failed to lift onto its step as expected. A subsequent inspection of the right float revealed that the second compartment from the front was completely filled with water, while the remaining compartments remained dry. As the pilot attempted to taxi to a sandy beach located three to five miles away, the nose of the seaplane submerged underwater.
The occupants exited the aircraft with some difficulty. Shortly after egressing, the plane rolled over, and a hole was identified in the number two compartment adjacent to the keel. One passenger remained with the wreckage until rescued. The other passenger is presumed to have drowned while swimming to shore alongside the pilot.
Findings
The primary contributing factor was the structural integrity of the right float. Specifically, the second compartment from the front sustained a breach, likely during the initial beaching or loading process, which allowed water ingress that prevented takeoff and ultimately led to the sinking of the aircraft.
Safety message
This incident highlights the critical importance of pre-flight inspections for amphibious and seaplane operations, particularly after beaching. Ensuring float compartments are watertight is essential for maintaining buoyancy and safety during subsequent water operations.