Flap with single servo 

No just build that long torque tube into the inside of the wing!! I have an Ov010 Bronco that I did that way but hid the torque tube in the wing. It runs four flap sections!!

how is flap servo working

Oi amigo o sistema de flap funciona para o que o avião, Fernando

compadre, estoy en el proyecto de realizar un airbus A321 y estoy buscando los sistemas electronicos para los flaps, spoiler, etc.. tu que me recomiendas? y como seria el circuito

OVERKILL!

A posicão do horn ta errada.

Very soviet

You installed The hinges in the wrong place

Bit agricultural.