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I'm building a Lippisch ground effect vehicle with it's wingtips almost touching the ground, but because of torque effects the left wing actually does touch the ground, so it can't lift off. It even can't go straight. Adding ailerons isn't an option because this problem has to be solved on te ground (zero speed) and not in the air (because it doesn't get there). Does someone know something how I can solve this problem?

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    $\begingroup$ In what way is torque affecting things? $\endgroup$ – Jon Story Dec 8 '14 at 23:44
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    $\begingroup$ It is actually the reaction of the spinning propeller and motor who causes this problem $\endgroup$ – Simon Ravelingien Dec 8 '14 at 23:51
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    $\begingroup$ Is a contra-rotating propellor an option? $\endgroup$ – Jon Story Dec 8 '14 at 23:53
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    $\begingroup$ Now you're getting into small scale engineering, and out of the scope of the SE site, but I would have thought a bit of gearing would get you where you need to be $\endgroup$ – Jon Story Dec 9 '14 at 0:24
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    $\begingroup$ can't you put low-friction skids under the wingtips? and maybe even launch off a low-friction surface? $\endgroup$ – rbp Dec 9 '14 at 0:33
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The Lockheed U2 had the same problem (bicycle wheel base and they had to prevent one end being dragged on takeoff).

They solved it by adding "pogo wheels" that self detach on take off. (the ones on the orange sticks.)

enter image description here
(source wikipedia)

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The commenters are right: Either use two separate propellers (left and right) which turn in opposite direction, or use a counter-rotating prop.

enter image description here

This picture of a P-38 shows the principle. You can drive both props from the same engine by using driveshafts or belts. The Wright flyer had such an arrangement.

enter image description here

On small airplanes with very big engines a gearbox with concentric driveshafts is driving both propellers in opposite direction.

enter image description here

A simpler way to have contra-rotating props is to put them at opposite ends of an engine pod.

In all cases the prop torque is reduced to zero, or in case of the podded arrangement, almost zero.

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