The engineering standard is right-hand rotation. Point your right thumb at the propellor (from the engine side), and your fingers point in the direction of rotation. Same is true for right-hand rotation car & truck engines. Stand at the engine, point your right thumb in the direction torque is transferred, and your right fingers show the standard rotaion. If the engine rotates the other way, you have chosen a left-hand rotation design.
Seems reasonable to me,
Dave Olson
ORIGINAL: khodges
Seems like the thread on "why pull back to go up" was so popular, let's try this one: why do aircraft engines turn clockwise (as seen from the cockpit)? And to stir further controversy, why do Aerospatiale helicopter rotors turn opposite from almost every other helicopter?. Specifically excluded from this discussion are P-38 Lightnings and CH-46 and CH-47 helicopters, and the Flying Banana, whatever it's designation was. FO'ARD, HAARCH !!!!!!