Servo Tab, Control Tab

I've never heard of a 'control tab'. Do you mean 'trim tab'?
 
I know servo tab vs. anti-servo tab. One moves in the same direction as the associated control surface to lighten control force, the other moves in the opposite direction of control surface to increase control force/prevent over controlling; respectivly.

Aircraft with stabilators (a lot of Pipers) use anti-servo tabs to make the elevator feel more natural and help keep the pilot from over-controlling in pitch (artificial stability, basically).

MD-80s use servo tabs as the only method of moving their control surfaces. The pilot's yoke is connected to the servo tab, not the flight control itself, but when the tab is displaced it "flies" the surface that flies the plane. This is why you'll sometimes see MD-80s (and their relatives) taxiing around with a huge split between the two halves of the elevator.
 
Its a question on the ATP. A I've never heard of a control tab either but a friend is studying for the test and asked me.
 
Teller1900 said:
I know servo tab vs. anti-servo tab. One moves in the same direction as the associated control surface to lighten control force, the other moves in the opposite direction of control surface to increase control force/prevent over controlling; respectivly.

Aircraft with stabilators (a lot of Pipers) use anti-servo tabs to make the elevator feel more natural and help keep the pilot from over-controlling in pitch (artificial stability, basically).

MD-80s use servo tabs as the only method of moving their control surfaces. The pilot's yoke is connected to the servo tab, not the flight control itself, but when the tab is displaced it "flies" the surface that flies the plane. This is why you'll sometimes see MD-80s (and their relatives) taxiing around with a huge split between the two halves of the elevator.
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I actually gave him the same answer but he said its something different. :dunno:
 
Here's my guess of what they are talking about:

A servo or anti-servo tab moves with the control surface and affects the pressures proportionately with the amount of movement.

A control tab is set to one deflection and moves only when adjusted by the pilot.

Joe
 
Areeda said:
Here's my guess of what they are talking about:

A servo or anti-servo tab moves with the control surface and affects the pressures proportionately with the amount of movement.

A control tab is set to one deflection and moves only when adjusted by the pilot.

Joe
Click to expand...

Ahh ya, I forgot about that. Like what the Cessna has on the bottom of the rudder. Isn't that just a fixed trim tab, though? Or is it called at control tab?
 
I don't think a control tab is fixed. I think it's more like a pilot controlled tab, similar to a trim tab, on the trailing edge which then moves the main control surface through aerodynamic forces. That's my guess for the morning. :dunno:
 
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A control tab is a servo tab controlled directly by the pilot's flight control whose purpose is to cause the control surface to move in response to the pilot's control inputs. This is an alternative to the usual system of connecting the flight control to the control surface and using the servo tab for trim.
 
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