Accident Overview
On July 30, 2022, at approximately 0800 Pacific daylight time, a Cessna 177RG (registration N2591V) was substantially damaged during a landing approach to Livermore Municipal Airport (LVK), California. The pilot was not injured. The flight was operated under Title 14 Code of Federal Regulations Part 91.
Flight Sequence
The pilot departed Salinas Airport (SNS), California, after an uneventful preflight inspection and engine runup, with the intended destination of LVK. About 30 minutes after takeoff, the engine monitor indicated an increase in exhaust gas temperatures (EGTs) for all cylinders. The engine briefly stuttered, prompting the pilot to consider diverting to an en route airport for a precautionary landing. After adjusting the fuel mixture control, the EGTs returned to normal, so the pilot decided to continue to LVK. Approximately 10 minutes later, during the landing descent, the pilot reduced engine power and moved the mixture to full rich. The EGTs again began to rise, and the engine lost all power.
Damage and Ground Impact
The airplane struck a set of instrument landing system lights short of the runway, resulting in substantial damage to the left wing and stabilator.
Postaccident Examination
A postaccident examination revealed no anomalies with the engine or airframe. The engine could be operated at varying speeds during a ground run. Review of engine monitor data showed an EGT increase of about 200°F. During periods of EGT rise, fuel flow did not change discernibly. The fuel flow transducer was installed at the inlet of the fuel injection servo, rather than the outlet to the flow divider.
The airplane was equipped with a Bendix RSA-5AD1 fuel injection servo. The servo and flow divider were tested at Precision Airmotive’s facility and met performance specifications for a field overhaul. However, disassembly revealed significant internal corrosion and corrosion deposits throughout. The diaphragm cavities showed water lines and corrosion on both metered and unmetered fuel sides, consistent with water contamination. Corrosion deposits were also found in the servo valve seat cavity and mixture control assembly.
Maintenance History
Precision Airmotive Service Bulletin PRS-97 revision 2 (August 2013) states that the time between overhaul (TBO) for fuel injection system components is either the same as the engine manufacturer’s TBO or 12 years since placed in service or last overhauled, whichever occurs first. The bulletin also mandates overhaul if the fuel system is contaminated with water.
Maintenance records indicated the fuel injection servo was last rebuilt in August 1999—23 years before the accident—during an engine overhaul. Another engine overhaul in August 2012 had a logbook entry stating no accessories were overhauled. No maintenance entry indicated the fuel system had been exposed to water, though the gascolator had been recently replaced without a corresponding logbook entry. The mechanic who performed the most recent annual inspection stated he did not replace the gascolator. The airplane had no significant periods of inactivity recorded, but the owner noted it sat idle for 6 months before his purchase in June 2020 and was kept in a hangar for much of its recent life.