Bell hot fast start explanation letter
I am trying to track down a copy of a Bell letter that explains why a hot fast start is better than a cool one. Not just the spiel about the reduced time taken.
It was along the lines of explaining that where the temperature is being read is not where the damage was being done and until the engine is up to speed the cooling airflow is unable to do what it is supposed to. From memory it was typed on a typewriter and late 70's or 80's.
I believe the engines in question were the 250 series. There is also a possibility the letter was issued by the engine manufacturer.
Any help would be appreciated.