How are trim tabs adjusted in relation to the desired movement of the surface being controlled?

Trim tabs are adjusted opposite to the desired movement of the control surface they are associated with in order to create a balance and reduce the pilot’s workload. When a pilot wants a control surface, such as an elevator or aileron, to deflect to a certain position, they can adjust the trim tab on that surface to create a counteracting force. This counteraction helps to maintain the desired flight attitude with minimal effort.

For example, if the pilot wants to raise the nose of the aircraft, they would deflect the elevator up. To assist this action and maintain the desired attitude without continuous input from the pilot, they would adjust the trim tab downwards. This configuration provides aerodynamic balance, allowing the control surface to hold its position more effectively.

The other options do not accurately reflect the mechanics behind trim tab adjustments. Adjusting the trim tab in the same direction as the desired movement would result in increased workload rather than relief, while only adjusting them during extreme conditions wouldn't utilize the benefits trim tabs offer for routine adjustments. Lastly, stating that trim tabs are not adjusted ignores their important role in flight control and stability management.