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## Anti-balance Tab

• yourgurltans
• Topic Author

### yourgurltans created the topic: Anti-balance Tab

Hi

An anti-balance tab operates by moving
a. Opposite to the direction of movement of the control surface to resist it's deflection
b. In the same direction as the movement of the control surface to resist it's deflection
c. Opposite to the direction of movement of the control surface to assist it's deflection
d. In the same direction as the movement of the control surface to assist it's deflection

• Posts: 1169

### Richard replied the topic: Anti-balance Tab

G'day,

A balance tab or servo tab works like a "servant" to help with the control load and make it easier to deflect the control surface.
An anti-balance tab is therefore an anti-servo tab which acts to make it harder to deflect the control surface.

So the answer has to be (a) or (b).

Now, a balance tab on the elevator will help make the deflection easier. As the elevator is deflected upwards the tab is deflected downwards to generate an aerodynamic force which gives an extra "push" on the control surface to assist your efforts.

As the elevator moves up, the servo (or balance) tab moves down.
As the elevator moves down, the servo (or balance) tab moves up.

The servo tab moved in the OPPOSITE direction to the control surface to HELP you. Therefore, the anti-servo (or anti-balance) tab must move in the SAME direction as the control surface to make it HARDER to deflect the control surface.

The answer must therefore be (b).

Cheers,

Rich