Cessna 172Q N96145 accident near Big Timber, Montana

Probable cause

A loss of engine power during climbout for undetermined reasons.

NTSB analysis

The flight instructor and student pilot departed on an instructional flight to a nearby airport in dark night conditions. After an uneventful inbound flight, the student pilot configured the airplane to land, but then elected to perform a go-around due to the airplane’s high altitude during the approach. The instructor instead asked the student pilot to overfly the runway. After the airplane reached the departure end of the runway, the student pilot started a climb; as the airplane was passing 250 ft above ground level (agl), the engine lost power, followed by vibration-induced noise. The instructor took control of the airplane and turned the airplane back towards the airport as he struggled to maintain airspeed. The airplane subsequently impacted frozen ground during the descent and sustained substantial damage to the fuselage.

Both the instructor and student pilot reported a loss of engine power and an abnormal sound described by the instructor as a vibration-induced noise. The instructor later recalled that the airplane lost all power, which could not be confirmed because evidence obtained from the propeller examination suggested the propeller was likely rotating under power at the time of impact.

The reason for the loss of power, the vibration-induced noise, and amount of power produced by the engine at the time of impact could not be determined due to lack of available evidence and postimpact damage.

Text from the NTSB. Open the NTSB docket for WPR20LA068 for the full record.