Cessna 172 N7137T

Summary

On 16 July 2021 at about 20:30 local time, a Cessna 172 registered N7137T was involved in an accident near Skwentna, Alaska, United States. 2 people were on board and 2 had minor injuries. The aircraft was substantially damaged. The NTSB has published a probable cause for this accident; it is quoted in full below.

Date

16 July 2021 at 20:30

Classification

Accident

Location

Skwentna, Alaska, United States

Coordinates

61.9190, -150.9915

Aircraft

Cessna 172

Registration

N7137T

Category

Airplane

Year built

1959

Engines

1

Operator

Not recorded

Operating rule

Part 91: General Aviation

Purpose of flight

Personal

Phase of flight

Not recorded

Route

Unknown → Skwentna

Aircraft damage

Substantial

Weather

VMC

Light

Day

NTSB number

ANC21LA061

2 people had minor injuries.

A partial loss of engine power due to detonation/preignition damage to the No. 2 cylinder. The reason for the detonation/preignition damage could not be determined based on the available evidence.

Quoted verbatim from the NTSB record. This site does not paraphrase or interpret it.

Read the full NTSB narrative

The pilot reported that during takeoff from an off-airport gravel bar on a river, the airplane experienced a partial loss of engine power. The pilot rejected the takeoff, and the airplane subsequently encountered a “bump,” which pitched the nose down. The pilot then made a hard right turn to avoid going into the water, and the airplane nosed down and impacted the ground with the left wing, which resulted in substantial damage to the left wing. Postaccident examination revealed that the No. 2 cylinder would not produce compression. Removal of the No. 2 cylinder revealed damage, including a hole in the piston that was consistent with detonation and/or preignition. The reason for the detonation and/or preignition could not be determined based on the available evidence.

Quoted verbatim from the NTSB record.