The recent eruption of the Iceland volcano has prompted many
questions from the piston powered general aviation community. This
announcement is intended to address current concerns regarding
operation and maintenance of Lycoming aircraft engines in
atmospheres contaminated with volcanic ash.
Given the dynamic conditions associated with volcanic ash, Lycoming
advises Operators against engine operation in areas where volcanic
ash is present - in the air or on the ground.
Piston engines can be adversely affected by inlet air contaminated with volcanic ash.
Solid deposits from any number of sources can accumulate on engine
baffles or other engine surfaces significantly impacting engine cooling.
Accumulation of deposits on the induction air filter can restrict or block air flow to the engine and significantly reduce engine power.
Contamination of engine oil can lead to engine malfunction and/or
failure from abrasive wear.
It is also important to note that ash on the ground and runways can
inadvertently contaminate the engine compartment and cause engine
damage as the aircraft lands or takes off.
The complete notice and recommendations is attached