ORIGINAL: MajorTomski
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ORIGINAL: Yes, the word torque is not being used in the strict physical description, and I have a large physics background so I know what torque is, and I try to keep an open mind, but until someone actually offers evidence that only #4 on that list is correct and the other 3 don't apply in any way shape or form to yaw, I'm sticking with my myth.
Cheers.
John please read my answer in the context of the thread. Steven asked what do thrust angles do for an airplane The first three answers all said they haves something to do with torque.
Within the context of his question I repeat my simple answer and stand by the simple fact that an offset thrust line cannot have any effect on reducing the effects of torque.
Right thrust cannot have an effect on left rolling of an airplane due to items 1 and 3 on your list.
Right thrust cannot have an effect on the slipstream spiral, if you choose to believe it exists, it would simply point it further to the left of the fin, making the slipstream effect more pronounced. so there goes #2. By the way you will only convince me that this myth exists when you show me the set of formulas, in any aviation performance book that mathematically resolve the magnitude of this supposed slipstream for a given horsepower/torque and number of propeller blades. (I've looked at all 38 performance books in the FAA library at Oklahoma City and those equations don't exist. Most of the books quote Stick and Rudder verbatim. Books that predate Stick and Rudder don't even discuss spiraling slipstream.
That leave #4 what causes the majority of left yaw on a single engine plane and what defines the critical engine on a multi engine plane, off set thrustline from P factor.
As for quoting the FAA, I believe the current version of that book has eliminated all reference to spiraling slipstream. But my copy's at work.
And poor Copernicus was excommunicated and is spending an eternity in Hell because he dared to challenge the official position.
Teaching something wrong will never make it right. It will always be a bad explanation for what is really happening. Aero engineering and the associated performance issues are precise sciences. I cannot stand this constant dilution of that science by pseudo science incorrect explanations.
T. Solinski
Aero Engineer
FAA Aviation Safety Inspector
Private Pilot, SEL, MEL.