Originally Posted by
adamlouis
Very simple question, what is the critical engine on the Dash-8 Q400.
Very simple answer: none.
Due to P-factor (downgoing blade producing higher lift as it has higher AoA and a bit of forward velocity imparted by the aeroplane, when the aeroplane alpha is positive) the thrust centerline on the Q400 (and most western twinprops) is offset to the right, therefore No2 has longer moment arm and No1 failure requires more rudder than No2. Practically, the difference in handling is imperceptible.
There are some airframe/powerplant combination where the phrase "critical engine" really means something. It is kind of useless and potentially dangerous "knowledge" to assume that because your twin trainer behaved differently whether you lost left or right donkey, all the multiprops in your flying life will do the same.
BTW, there is no critical engine on ATR-42 300 either.