All signs in the system are managed according to the international aeronautical axes convention: It is considered positive any deflection that generates positive rotational forces or moments about the aerodynamic centre of the aircraft, except for “y” axis (elevator) where it is considered negative a positive moment.

 

fig.002-sign-convention

Sign Convention

Example, an elevator down position will generate a positive pitch so the elevator is considered positive on down position. Main actuators rules:

ActuatorPositiveNegative
ElevatorDownUp
RudderRightLeft
Right AileronUpDown
Left AileronDownUp
Tail RotorRightLeft

 Actuator Configuration