Originally Posted by
DuncanDoenitz
Of course, when the airframe designer decides to equip contra-rotating engines, usually to address the problems of "critical" engine failure, it is the right-installed engine which undergoes the change. Hence, the left-side engine of a Chieftain has right-hand rotation, and the right-side engine has left rotation, and a left-hand prop.
With the exception (sole, I think) of the 700P variant of the Aerostar, which had outward-rotating props and so the LTSIO-540 is the left engine.