Incident Overview
A pilot reported that he and his wife were engaged in sightseeing along the Yellowstone River, just south of Laurel, Montana, when he observed what he described as unusual animal tracks on a gravel sand bar adjacent to the river. The pilot applied one notch of flaps and executed a 180-degree course reversal to obtain a "low and slow look" at the tracks. During this maneuver, the aircraft struck the water and nosed over. The pilot stated that there was no mechanical malfunction or failure with the aircraft or its powerplant or systems.
Sequence of Events
The flight was proceeding normally along the river when the pilot spotted the tracks. He configured the aircraft with flaps and turned around to get a closer view at reduced speed and altitude. The aircraft subsequently contacted the water surface and flipped onto its nose. The pilot did not report any anomalies with the aircraft's operation prior to the water strike.
Pilot Report
According to the pilot, the aircraft experienced no mechanical issues. He indicated that the entire event was a result of the decision to descend to a low altitude for observation. The pilot and his wife were uninjured per the report, though the aircraft sustained damage from the nose-over.
Investigation Findings
The investigation relied solely on the pilot's account. No evidence of pre-impact mechanical problems was found. The circumstances point to a controlled flight into terrain, with the terrain being water. The pilot's choice to fly at low altitude during the turn was contributory to the accident.