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Flaps Will Not Deploy inflight

Russ Barr

I'm New Here
Flaps were working fine before being sent to paint. Flaps will deploy on the ground but will not deploy in flap range in the air. Tape was added to prevent scratching the flaps. Any help appreciated.
 
I'm guessing that the flap motor is being stymied by a combination of air load and the frictional drag from the installed tape. Is a CB popping when this happens? Also check to make sure that the CB rating is appropriate for the flap motor.
 
Tell us a bit more about the control architecture -- e.g. VPX or G3X/GAD27 driving the flap motor? Does the flap motor make noise then stop? Is there an indication of overload (blown CB, flashing lights on the CAS, VPX info screen?)

*edit*

Is it possible the Flap/Airspeed values in the VPX and G3X are not configured correctly?
 
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Do you have a controller? When I changed my panel, I wired the controller connections incorrectly (power to sense instead of input), which apparently allowed the flaps to operate and somehow didn't fry the controller but the current flowing back through the sense was not enough to deploy the flaps in flight. Switched and all was well again. If you aren't using a controller, then look for any binding.
 
I had a similiar problem when I first started the Phase 1 on my RV-10. The flaps worked fine on the ground, both up and down, but would not deploy in flight after they were retracted. It turned out that the flap motor end was was at the end of the threads at reflex position and with air pressure while in flight, would not allow the threads to re-connect to the jack screw. A little adjustment was all that was needed.
 
One more thing to look at.

Have a very close up look where the actuator arm is welded to the bellcrank tube.

Low probability of this being your issue but I have experienced the same symptoms where a hairline not very seeable crack allowed the arm to move when the actuator extended, but the torque tube would not rotate under air load.

On the ground the flaps would extend and retract every time. In the air they would not extend. The crack would act like a torsion spring in flight.
 
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