FAA updates AC on engine power-loss accidents

The AC highlights and discusses several operational causes of engine failure that include inadequate preflight inspections, fuel contamination and misfueling, collapsed fuel bladders, exceeding time between overhauls, poor engine operating technique, and maintenance mishandling. Lack of pilot training and mismanagement of the engine control systems by the pilot remains the leading cause of engine failure.

In addition to accident prevention, the “AC provides generic data collection charts to assist with setting up a reciprocating engine trend monitoring program to improve and track both engine and related system reliability over the recommended operating life of the engine.”

The FAA believes that many power-loss accidents are preventable if the owner/operator implements a training program for pilots and mechanics and incorporates an engine trend monitoring program.

Trend monitoring for reciprocating engines is the periodic collection and analysis of a select number of engine readings and indications that can predict a failure before it happens. Trend monitoring should include inspection and monitoring of engine case components, cylinder and piston assemblies, and accessories like the ignition, electric, and vacuum systems.

The generic trend monitoring charts can found in section 7.2 of the AC. Advisory Circular AC_20-105C cancels AC_20-105B, published in 1998.