Which engine should be counter rotating
09-02-2005, 12:09 PM
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Which engine should be counter rotating
I want to use a counter rotating engine on my Twin-Air. Will be using a pair of MVVS .49 engines. Which engine should be counter rotation - the left or the right when seen from behind the plane?
I know a counter rorating engine might not help much with stability but I think it will add to the cool factor.
Regards
Flemming
I know a counter rorating engine might not help much with stability but I think it will add to the cool factor.
Regards
Flemming
09-02-2005, 12:27 PM
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RE: Which engine should be counter rotating
Flem:
From the pilot's perspective the right side engine is the one to be reversed rotation.
Why?
Two considerations for off center power, thrust line and the torque of the engine.
With the left engine running by itself the off set thrust tries to pull the plane to the right, but the torque reaction tends to put the plane in a left bank. Threrfore the torque cancels a bit of the off center thrust.
With the right engine only running in normal rotation the engine's torque still tends to the left bank, and the thrust pulls the plane into a left turn. Here, the two forces add and reinforce each other. By reversing the rotation of the right engine you have the same subtractive effect given with the left engine turning normally and running by itself.
Clear? Hope so.
Bill.
{edit for left out letters}
[b]
From the pilot's perspective the right side engine is the one to be reversed rotation.
Why?
Two considerations for off center power, thrust line and the torque of the engine.
With the left engine running by itself the off set thrust tries to pull the plane to the right, but the torque reaction tends to put the plane in a left bank. Threrfore the torque cancels a bit of the off center thrust.
With the right engine only running in normal rotation the engine's torque still tends to the left bank, and the thrust pulls the plane into a left turn. Here, the two forces add and reinforce each other. By reversing the rotation of the right engine you have the same subtractive effect given with the left engine turning normally and running by itself.
Clear? Hope so.
Bill.
{edit for left out letters}
[b]
09-02-2005, 05:26 PM
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RE: Which engine should be counter rotating
[b]Why does everybody post such dark pictures? I couldn't even see Evan in the second picture until I redid it in Paint Shop.
Good looking plane anyway.
Bill.
Good looking plane anyway.
Bill.
