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Miracerdin
26th Jan 2015, 13:21
Why we dont feel tork effect while in the air, airborne pozition.:confused

pattern_is_full
26th Jan 2015, 16:54
Short answer: stronger control effectiveness and natural stability with increasing airspeed make the "tork" less obvious.

(Digressionary answer: Lose your tail rotor in a helicopter, and you'll definitely "feel tork effect while in the air"!. The helo spins around the rotor shaft, making control virtually impossible.)

Long answer: "Tork" in airplanes is of course actually a combination of several effects: true engine torque (which is only a small component); spiral propwash; p-factor (only when the nose/prop disk is pitched up compared to relative wind); gyro precession (only if the nose pitch is being changed).

Prop disc gyro precession is only significant during rotation (raising the nose) for take off (or raising the tail in a tail-dragger). Once you are in a steady climb or cruise, it doesn't exist.

P-factor is only significant when the relative wind is at an angle to the prop disk other than 90 degrees. E.G. a steep climb at a low airspeed and high AoA/nose pitch. The faster you go (and the more the nose pitch is lowered), the closer the angle gets to 90°, and the lower the p-factor, reaching effectively zero in a cruise climb or cruise.

Engine torque - the engine splitting its power spinning the prop in one direction and trying to roll the rest of the aircraft in the other direction - is rather small in most aircraft, relative to the other effects. Someone did the calculation, and the net torque force in a Cessna 172 is about 200 ft/lbs - equal to a 200-lb passenger sitting on one side of the cabin or the other.

Flying solo in a 172, your own off-center weight is adding nearly as much left-roll tendency as the engine itself.

On the ground, where the landing gear prevent significant roll, the effect is just to press one wheel into the ground a little harder, adding friction on that side, and resulting in some YAW. Once airborne, with increasing speed, the stabilizers do just what they are named for - their flat surface areas fight against (resist, stabilize) the small roll tendency.

Additionally, "torque" actually decreases as speed gets closer and closer to the "design speed" of the propellor. The speed of the air through the prop means the engine/prop system is simply adding enough power to maintain speed against drag, rather than produce acceleration. The situation gets close to being a "steady state".

Ultimately, in many small aircraft, small asymmetries are designed in to counter the remaining "torque" effects, especially at higher airspeeds. These can be - engine angled slightly to one side, vertical fin angled slightly to one side, an aileron "trim tab" to provide a little roll force opposite to the "tork" effects.

The net result gets back to the "short answer" - at higher speeds, with the ailerons and rudder and stabilizers more effective, it may take only a "finger's weight" of pressure on the yoke, or a "toe's weight" of pressure on the rudder, to keep things straight and level.

Too small to "feel," really.

Miracerdin
26th Jan 2015, 18:54
The net result gets back to the "short answer" - at higher speeds, with the ailerons and rudder and stabilizers more effective, it may take only a "finger's weight" of pressure on the yoke, or a "toe's weight" of pressure on the rudder, to keep things straight and level.
Can we say ıts effect minimized by rudder and ailerons and stabilizer.

pattern_is_full
27th Jan 2015, 22:06
....and higher airspeed