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In General Aviation light twins, when landing in heavy crosswinds, what are some considerations to using asymmetric (or Split) throttles to induce a sideslip, to align the fuselage with the ground track and the runway centerline instead of rudder?

I was told that this technique allows the aircraft to track down the runway centerlines with fuselage aligned with the runway without as much bank angle into the crosswind as would be required with symmetric thrust using cross-controlled rudder and opposite aileron alone.

I was thinking that the need for bank into the crosswind is due to the need to compensate for the sideslip force (from the yaw due to downwind rudder) which would otherwise (without the bank) turn the aircraft downwind.

But it seems to me that using asymmetric thrust to induce the same sideslip would produce the same tendency to turn if the wings were not banked into the crosswind to compensate. Why not??

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The use of asymmetric thrust when landing a twin in a crosswind effectively accomplishes the same thing that rudder input does. It induces a yawing moment about the aircraft’s vertical axis, the same as pushing on the rudder pedals does. It helps to alleviate excess rudder pressure on the flight controls during the approach, making it a little more comfortable for the pilot to fly the approach. You are still required to apply aileron input into the wind in order to hold the runway centerline. Using asymmetric thrust during a Crosswind Landing does not alleviate aileron pressure or required bank angle to track the runway centerline.

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    $\begingroup$ That's as I thought. The only difference would be that when using asymmetric thrust, the rudder would not be as deflected. The vertical stabilizer (as well as the entire fuselage because of the sideslip angle) would still be producing lateral aerodynamic force in the downwind direction. So there would still be a need to drop the upwind wing to counteract that force to maintain a constant heading. $\endgroup$ – Charles Bretana Apr 13 '18 at 14:23

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