N4456LCessna 172G · 1966

On March 3, 2021, about 1745 Pacific daylight time, a Cessna 172G, N4456L, was substantially damaged when it was involved in an accident near Sisters Eagle Air Airport (6K5) Sisters, Oregon. The pilot sustained a serious injury and the passenger sustained minor injuries. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight.

The pilot reported she performed the airplane preflight and confirmed there was 16 to 17 gallons of fuel on board. The engine run-up was normal as was the flight to Bend Municipal Airport (BDN), Bend, Oregon, where she performed three touch-and-go landings. The flight then proceeded to Redmond Municipal Airport (RDM) where the pilot performed one touchandgo landing before flying back to 6K5.

The pilot reported that while on final approach to land at 6K5, she performed a forward slip with the engine power at idle and the flaps retracted. She stated the landing approach 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 reported she attempted to restart the engine by increasing the mixture control to full rich, cycling the carburetor heat, and turning the magnetos. She then readjusted the mixture control and was not able to restart the engine. She did not switch the fuel tank selector during the attempts to restart the engine. Unable to regain engine power, the pilot initiated a forced landing to 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.

The pilot reported she leaned the mixture while en route to RDM and did not reposition the mixture control again until after the engine lost power. She also reported that she took off with the fuel selector in the BOTH position and switched to the left fuel tank upon reaching cruise altitude. She switched the selector to the right tank for the remainder of the flight after departing RDM.

A Federal Aviation Administration inspector reported that following the accident the right-wing fuel tank was almost empty and the left-wing fuel tank had fuel remaining. The inspector also reported the gascolator contained very little fuel.

A postaccident examination of the engine verified valve train continuity throughout the engine. Suction and compression were obtained on each cylinder when the propeller was rotated by hand. Both magnetos produced spark when tested. The spark plugs exhibited normal wear signatures. The carburetor was partially torn from its mount, but the carburetor itself was intact and clear of debris. The throttle cable and mixture linkage travel were normal. The carburetor heat valve was closed. Fuel present in the carburetor was clean and tested free of water. No mechanical anomalies were identified during the engine examination that would have resulted in the loss of engine power.

The Cessna 172 Owner’s Manual Before Landing checklist states the mixture control should be in the rich position for landing and the fuel selector should be in the BOTH ON position. In addition, the fuel selector was placarded BOTH TANKS ON FOR TAKEOFF & LANDING.

The Cessna Pilot Safety and Warning Supplements publication contains a warning titled, “Flight Coordination Vs. Fuel Flow” which states:

The shape of most airplane wing fuel tanks is such that, in certain flight maneuvers, the fuel may move away from the fuel tank supply outlet. If the outlet is uncovered, fuel flow to the engine may be interrupted and a temporary loss of power might result. Pilots can prevent inadvertent uncovering of the tank outlet by having adequate fuel in the tank selected and avoiding maneuvers such as prolonged uncoordinated flight or sideslips which move fuel away from the feed lines.