On July 18, 1998, a Cessna A185F (registration N1481F) operated by George F. Marshall was involved in an aviation accident near Moneta, VA. Investigators recorded the probable cause as: The pilot's descent during a turn to avoid terrain, which resulted in the right float contacting the water and subsequent loss of control. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive.
An amphibious airplane sank after its right float contacted the water during a turn to avoid terrain, flipping the aircraft over. No mechanical failures were found.
What happened
The amphibious airplane commenced a normal takeoff run from the surface of a lake before lifting off into the air. Shortly after becoming airborne, the pilot initiated a turn intended to avoid nearby terrain obstacles. During this maneuver, the aircraft descended in altitude until its right float made contact with the water surface.
Following the initial float impact, the airplane began to cartwheel across the water. The violent motion caused the aircraft to flip over completely before sinking beneath the surface. There were no reports of mechanical issues prior to the incident.
The investigation
Investigators examined the wreckage of the amphibious airplane following its recovery from the lake. The examination focused on the structural integrity of the airframe and the condition of the engine components. No evidence of pre-impact mechanical malfunctions was found in either the airframe or the engine systems.
Probable cause
The pilot's descent during a turn to avoid terrain, which resulted in the right float contacting the water and subsequent loss of control.