Cessna 177B N34713 accident near Tucson, Arizona

Probable cause

A partial loss of engine power due to restricted fuel flow resulting from foreign object debris in the fuel flow transducer.

NTSB analysis

The pilot reported that the accident flight was the first flight after an engine overhaul had been completed the pilot departed from the runway after conducting initial engine break-in procedures on the ground. The last ground break-in procedure called for the pilot to apply full power for 5 seconds. During this task, the airplane jumped the chocks before reaching the 5-second mark, so the pilot shut down the engine and the engine ground runup break-in procedure was not completed. During the initial climb, the pilot informed the tower controller that the airplane was not achieving the climb-out performance needed and requested a 180° turn back to the runway. The pilot initiated a left turn; however, the airplane impacted the ground in a left-wing-low and nose-low attitude about 2,085 ft east of the departure end of the runway.

Postaccident examination of the airplane’s engine revealed no evidence of preimpact mechanical malfunction. Examination of the air induction and exhaust systems revealed no evidence of preimpact mechanical malfunction or failure. However, examination of the fuel flow transducer revealed a 5/8” x 1/4” polymer strip inside of the fuel entry port bore.

The airplane was equipped with an engine data monitor. Postaccident examination of the accident flight engine data revealed that the engine rpm decreased, the exhaust gas temperature and cylinder head temperature increased, and the fuel flow gradually decreased throughout the flight. The foreign object in the fuel flow transducer, likely resulted in a fuel flow restriction and partial loss of engine power. The engine logbook revealed that all fluid carrying flexible hoses were replaced prior to initiating engine break in procedures, and it is likely that the foreign object found in the fuel flow transducer was introduced to the fuel system during installation of the fuel carrying flexible hoses.

Text from the NTSB. Open the NTSB docket for WPR23LA201 for the full record.