If the propeller turns clockwise, why doesn't the plane turn counterclockwise to balance the torque?

Question

In helicopters, torque balancing is done by the extra rear propeller. But in airplanes, no such balancing is evident. Even the engines of jumbo jets turn all in the same sense. For stability, the Sum of all torques MUST be 0. Is the sum of the propellers or jets torques so small as not to influence equilibrium? If not, what is the mechanism used to stabilize the plane? It seems to me that, except for helicopters, all propellers are small BUT they turn very fast. So, the momentum generated must be quite large. Please feel free to use engineering notation in your answer. Thanx!

Answer 1

The plane does turn somewhat. In a single engine prop plane, the forces are counteracted by the pilot or computer actuating the ailerons and rudder. For multiple engine prop planes, they often make one engine turn one way, and the other one turn the other to mostly counteract each other. Some pilot input is still required as nothing is perfectly balanced.

For jet engines, the effect is much less, due to the design of the engine. What force is created is again counteracted by the control surfaces of the aircraft.

The force is most noticable when accelerating and decelerating the engine. When it's at a constant velocity, the torque to the whole system is much less.

Answer 2

Close.
For every action there is an equal and opposite reaction.
A single prop plane will have a torque effect going in the opposite direction.
This is countered by the vertical stabilizer and rudder.
With forward motion it is less pronounced. Wings actually have a "wash in"wash out" curvature designed to help counteract torque.
When a plane is in slow flight IT CAN turn the plane into a spin.
Slow speed + high engine revs will turn the plane in the opposite direction of rotation.
So yes there is a momentum as you put it with the rotating prop.
It acts like a gyro.
If you watch aerobatic planes they use this technique, torque to move their plane wildly.
I do it all the time. i am an aerobatic pilot.
The helicopter rotors move so much air the torque is huge, which is why they need a counter force.
So I hope this answered your question.

Answer 3

The plane does indeed experience torque from the props. However, the mass of the propellers is so small in relation to the mass of the airplane that the wings and the tail only need to exert a relatively small amount of torque on the body.

As for the engines on a jumbo jet, if you do a force diagram, treating each wing seperately, you find that the force generated by the torque at the fuselage (convert torque at engine location to force at fuselage) cancels out when the turbines spin the same way.

CW = clockwise

(CW)=========[F = down].....O....[F = up]==========(CW)

Answer 4

Because the rigging of the wings and tail is set to apply an opposite torque. The torque varies with engine speed, of course, so the pilot will supply a slight correction with rudder trim to keep things level at different power settings.

Answer 5

You're right about the torques.

The flaps on the main wings also produce torque on the airplane when they are raised or lowered. They are adjusted in order to counter the torque produced by any change in prop speed.

Answer 6

Trim tabs are used in many planes to counteract prop torque. Some are fixed (in smaller planes); they are pieces of sheet metal bent to provide cruise trim (see the paragraph "trimming" in ref. 1). Others can be adjusted in flight (ref. 2). And of course most larger planes have closed-loop systems that automatically correct for all torque disturbances using the ailerons and movable tail surfaces.

Answer 7

That is what the vertical Stabilizer is for along with the rudder to counter yaw and P factor

BTW most props turn counterclockwise

Answer 8

Because the plane would fall out of the air!!!