Will My Helicopter Fly Straight?
To determine how much force the tailrotor and vertical tail must produce, we use dimensions shown in the sketch.
For this example the following is given:
Rotor torque @ Hover: QH = 10,000 ft-lbs
@ 150 mph: Q150 = 15,000 ft-lbs
Distance from rotor to tailrotor: tr = 20ft
Distance from rotor to vertical tail: vt = 22ft
The tailrotor will produce less force in forward flight than in hover. For our example assume that the tailrotor force at 150 mph is 10% of the force at hover.