SmartCockpit Dash8-200, Manual

Roll control 

Roll control is by conventional cable-operated ailerons, augmented by cable-operated, 
hydraulically activated, roll spoilers. The rotational movement of the pilot's control wheel 
activates the roll spoilers while the co-pilot’s control wheel activates the ailerons. An 
interconnect linkage joins the pilot's and co-pilot’s control wheels so that both systems are 
operated from either wheel. A clutch within the linkage can be disengaged manually, by 
means of a roll disconnect handle on the flight compartment centre console, to separate the 
left and right roll control circuits in the event of a jam in either circuit. With the control circuits 
separated, control can be maintained with the un-jammed control wheel. 
 
 

Ailerons 

An aileron is located on each wing outboard of the flaps. Rotation of either control wheel 
actuates the ailerons differentially by means of a cable control loop, with inter-connection to 
applicable roll spoilers. 
 
Geared tabs on the trailing edge of each aileron assist aileron deflection. The tabs are 
geared to a static position, which is aerodynamically neutral relative to the aileron. When the 
aileron is deflected, the geared tab moves in the opposite direction creating a localized lifting 
force about the tab in the direction of aileron deflection, thus assisting aileron movement. 
 
The right aileron trim tab, using an electric actuator built into the aileron, provides aileron 
trim. A L/R AILERON rocker switch, located on the TRIM panel on the centre console 
operates the actuator when depressed to the left or right. The actuator trims aileron control 
pressure by biasing the static neutral position of the trim tab. An indicator adjacent to the L/R 
AILERON rocker switch shows the degree of trim actuator displacement from neutral. 
 

Dash8-200/300 - Flight Controls

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