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Old 21st Jan 2017, 07:33
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27/09
 
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piperboy84: Is that because asymmetrical thrust on twins with non counter rotating props equipped with sub 200hp engines is easily held in check with the roll and yaw inputs even when it's a critical engine failure?
The asymmetrical thrust is easily held in check on any relatively modern twin, I'm talking anything certified since the late 1950's early 1960's, no matter the horsepower. Sure some will be easier than others.

Even high powered twin don't have C/R props, I'm not aware of any turbo props with counter rotating props.

The only benefit of a C/R set up is a reduced minimum control speed when airborne (Vmca). An engine failure close to Vmca (since you're well below the best single engine rate of climb speed) pretty well means you're now flying a single that cannot climb (or most likely not even maintain height) therefore you're landing anyway.

You might as well treat it like a single that has had an engine failure, close the other throttle and carry out a landing while you still have control. Whether or not your Vmca is for example 70 knots rather than 75 knots is a bit irrelevant in my book.

I'd rather have the extra performance.

To give an example Piper had to increase the HP on the PA31 Navajo from 310 on the non C/R model to 325 on the C/R model to get the same performance.
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