On June 23, 1992, a Stinson 108-3 (registration N6470M) operated by Anderson, Allan L. was involved in an aviation accident near Corbett, OR. Investigators recorded the probable cause as: THE FAILURE OF THE FLOAT ATTACH FITTING, AND THE SEPARATION OF THE FLOATS FROM THE AIRCRAFT. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive.
A Stinson floatplane sank after its floats separated during flight. The pilot, unaware of the separation, attempted a normal water landing, causing the fuselage to impact the water.
Incident Overview
A Stinson floatplane experienced a structural failure shortly after takeoff from rough water. The pilot reported a loud pop in the right front area of the aircraft during climb, followed by severe vibration. This prompted a decision to perform a precautionary landing.
Sequence of Events
The aircraft had climbed to approximately 200 feet above the river when the loud pop was heard. The pilot, not realizing that the floats had separated from the airplane, attempted a normal water landing. Upon touchdown, the fuselage impacted the water directly, and the aircraft ultimately sank.
Investigation
The investigation focused on the separation of the floats from the airframe. No probable cause was determined from the available information.