Cessna 172G N4456L accident near Sisters, Oregon

Probable cause

A total loss of engine power due to fuel starvation and the pilot’s mismanagement of the available fuel.

NTSB analysis

The pilot reported she took off with 16 to 17 gallons of fuel and returned to the departure airport following a 1 hour 15-minute flight that included four touch-and-go landings at two airports. During the final landing approach, the pilot performed a forward slip with the engine power at idle. The pilot reported the airplane’s airspeed was fast and the airplane bounced on the runway. She applied a “quick burst of throttle” to recover from the bounced landing but was unsuccessful, so she elected to perform an aborted landing. The pilot reported that she applied “almost” full power, removed carburetor heat, then applied the remaining power at which time the engine lost all power. The airplane was at an altitude of about 150 ft above ground level when the power loss occurred. The pilot attempted to restart the engine but did not switch fuel tanks. Unable to restart the engine, the pilot made a forced landing in an open field. The airplane came to rest in a nose-down attitude with substantial damage to the empennage, both wings, and the forward fuselage.

An on-scene examination of the airplane revealed the right fuel tank was almost empty and the left fuel tank contained fuel. A small amount of fuel was present in the gascolator. The pilot reported the fuel selector was positioned on the right fuel tank during the landing. A postaccident examination of the engine did not reveal any mechanical anomalies that would have resulted in a loss of engine power.

The pilot reported the mixture was leaned during the flight and landing. The Cessna Before Landing checklist states the mixture control should be positioned to the Rich position before landing. The checklist also states that the fuel selector should be positioned to the BOTH ON position. This procedure is also placarded on the fuel selector. Cessna issued a Pilot Safety and Warning Supplement that cautioned against the possibility of unporting the fuel supply outlet in the fuel tanks during uncoordinated flight, such as slips, with inadequate amounts of fuel in the fuel tanks.

Given the small amount of fuel found in the right fuel tank, which was the tank selected, the loss of engine power likely occurred due to fuel starvation as a result of the pilot’s failure to ensure an adequate amount of fuel on board and the failure to have the fuel selector positioned to both fuel tanks during the landing. It is unknown what role the pilot’s decision to perform a forward slip during final approach or her failure to have the mixture control in the full rich position played in the loss of engine power.

Text from the NTSB. Open the NTSB docket for WPR21LA122 for the full record.