On July 17, 2001, a Piper PA-12 (registration N918TF) operated by Nicolai, William S. was involved in an aviation accident near Oregon City, OR. Investigators recorded the probable cause as: The front seat (pilot-in-command's) inadequate visual lookout during step taxi resulting in the aircraft's collision with a partially submerged log. A contributing factor was the log and it's lack of any conspicuous marking. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive.
During a step taxi on the Willamette River, a floatplane's right float struck an unmarked submerged log, causing a breach. The aircraft nosed over and sank.
Accident Overview
A private pilot-in-command, who was not floatplane-rated, was accompanied by an ATP-rated flight instructor in the rear seat. The aircraft was step taxiing on the Willamette River in preparation for takeoff. During the taxi, the right float of the aircraft impacted an unmarked submerged log that protruded approximately 15 inches above the water's surface.
Sequence of Events
The impact breached the right float. Subsequently, the aircraft gradually nosed over and sank. No further details about the aircraft, occupants, or injuries were provided in the source.
Investigation
No probable cause was stated in the source. The investigation would likely examine the circumstances of the taxi and the presence of the unmarked obstacle.