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View Full Version : Anti-torque on Eurocopter X3


tartare
17th Jun 2011, 02:04
A question for helicopter specialists.
When viewing an X3 promotional video, a designer states the propellers provide propulsive thrust in level flight, and anti-torque function in the hover.
How do they do the second thing?
Does one side automatically go into increasingly course Beta pitch and the opposite side go into increasingly coarse Alpha pitch as it progressively translates to the hover?
Do the propellers rotate in opposing directions (although i can't see how that would affect anti torque)
Or does the mere fact of having two props on the end of two long levers (the wings) create an anti-torque effect by keeping the airframe stable in the yaw axis?
Confused...

keesje
17th Jun 2011, 19:36
I don't know the details, but a battery of (laser) gyroscopes, fly by wire, FADEC and good software can make anything stable..

keesje
20th Jun 2011, 19:24
Nice HD X3 clip from Paris.

YouTube - ‪X3 Flight Demo at the Paris Air Show 2011‬‏

Specially climb looks impressive compared to a regular helicopter

der alte
28th Jul 2012, 21:02
Yes, the two propellers on short-span fixed wings rotate in opposing directions.

To counter the torque of the main rotor at low speed prop differential thrust is used. At high speed, remaining anti-torque function is realized by vertical fin flaps.