ATR42-300 operational procedure - engine cool time
A note in the "after landing" checklist (normal procedures) of the ATR42-300 states: keep engine running at least one minute at ground idle power (condition lever between MAX and MIN RPM) before shutdown to assist in reducing residual heat build up in the engine and nacelle. Can someone please help to explain the technical significance and impact on the economic life of the engine of keeping the condition lever at the minimum or maximum RPM stops or midway between the two stops i.e. in which exact position would you derive maximum economic benefit for the life of the engine. Thank you.