Here is a video of Bell V-280 Valor. Seems like the old definition of airplane's control is no longer hold for this kind of airplane. If you click the link, it will go directly to the part I want to ask. First, it made a yawing, or turning in its vertical axis so it can make direction change when it is being hover. However, this airplane has two rotors, and no tail rotor like in normal helicopter. Second, it made shifting or move to its left side. Third, it made backward (reverse) move, beside, of course, forward move when the rotors being up. How did it work?

Another part of that video is here. How did it make turn/banking when it is being cruise? Is it still follow the "normal" way by controlling its aileron?

Note: The answer posted here is not answered how does the V-22 Osprey make side moving, which it is one of my question, and it is very important.

Bell V-280 Valor is side moving


1 Answer 1


The yaw would be accomplished by angling one rotor a little forward, and the other a little backwards.

The shifting move to the side is accomplished by generating more thrust on one side. Either by increasing the rotor AOA (collective pitch) or increasing RPM. You increase the lift, until you have your desired roll angle, then you equalize the lift so you don't accidentally flop over.

Flying backwards is accomplished by angling the rotors back, like the opposite of the "pitch" part of the image below.

The turn/bank while in cruise is achieved by combining these principles, while also using its control surfaces. The V-tail works as both an elevator and rudder.

From the cruise turn you linked to, it looks like the rotors aren't fully forward.

I would guess that we're flying too slow to use our flaperons fully. The roll would be a mix of flaperon angle, and rotor collective pitch. All the while our V-tail would work as an elevator.

(On a side note, a cool thing happens with our yaw when we shift our rotors from up to fully forward. When we hover, yaw is accomplished as mention earlier. When the rotors are fully forward, If we exclude the V-tails yaw function, yaw would be accomplished by increasing the thrust on one engine compared to the other. The same way we would roll in hover mode, is now yaw in flying mode.)

Please let me know if i missed something, or if you have clarification questions!

Tilt Rotor Control System Design

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    $\begingroup$ Thanks a lot. You answered my questions completely, with graph too. It helped me a lot to easy understand. $\endgroup$ Commented Sep 8, 2021 at 14:48

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