Differential Thrust on a Trimotor. Anyone make it work?

[wavetrain75]

I'm starting a scratch build of a Sikorsky S-35, a trimotor built to be the first to cross the Atlantic. It crashed on takeoff and that was the end of it.

So has anyone worked out differential thrust on 3 brushless motors? I'll be using a DX8e. It uses 3 vertical stabilizers and the build would be simplified if they were just stationary.

 

[TEAJR66]

Not sure about spectrum. I would do differential thrust as usual and program a third channel to slave off throttle. Two outers on diff and center slave to throttle.

 

[earthquake]

Put the motor in the nose on a gimbal and pivot it side to side.

Casey

 

[Merv]

I agree with @TEAJR66, setup differential thrust on the two outside motor and have the center motor respond only to the throttle

 

[quorneng]

I could say leave the rudders fixed and simply turn using the ailerons but add differential.
It then doesn't matter how many motors you have as long as the thrust is balanced.
Works for me!

 

[tamuct01]

To do differential thrust on the two outboard motors you need a transmitter with at least 3 mixer slots. At least 1 to couple the throttle channel to the 2nd (or 3rd motor) and 2 more to couple rudder input to each of the outboard motors. In your case with the tri-motor, you will need 4 mixes. A standard twin needs 3 mixes.