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Old 24th September 2008 | 09:27
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Daniel_11000
 
Joined: Oct 2007
Posts: 221
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From: ITALY
Going back to my Engineering Flight Testing many years ago :
1)If the propeller are counter-rotating (whichever way): no critical engine.
2)If the propeller are counter rotating inner-tip-down : no critical engine , the Vmc is less than....
3) Propeller counter rotating outer-tip-down : no critical engine, however the Vmc is more than 2), as the outer blade (going down) has more thrust (due to its higher relative AoA) than the inner one.
4) propeller with same direction of rotation : the critical engine is that opposite to the sense of rotation (clockwise: critical engine is the left, because if it fails, the asymmetry is higher du to higher arm from the down-going right-engine propeller blade)

For what refers to engine 'torque' : torque transmits itself all over the aircraft , it is not important if the item generating torque is on the left wing, on the nose or on the right wing ; its effects are the same.

I hope to have given you some useful information
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