Definition
Small metal tabs attached to the trailing edge of a control surface, typically the rudder, that can be bent on the ground by a mechanic to correct a flight imbalance. They are not adjustable from the cockpit and remain in their set position throughout flight.
Plain English
A small bendable strip on the back edge of a control surface that a mechanic adjusts on the ground to fix a steady pull or push the pilot has been having to hold in flight. Once bent, it stays that way until someone bends it again on the ground.
Context Anchor
Seen in flight control system discussions, especially when describing trim devices that are set during maintenance rather than adjusted by the pilot in flight.
Why Pilots Care
They provide a simple, permanent way to trim the aircraft without adding weight or complexity from in-flight adjustable trim systems.
Analogy
It is like slightly adjusting a bent fin on a model airplane so it flies straighter, except on a real aircraft the adjustment is made carefully on the ground as part of maintenance.
Intuition Check
“Adjustable” does not mean the pilot adjusts it during flight. In this term, “ground adjustable” means it is set while the aircraft is on the ground, before the flight.
Example Sentence 1
After noticing the airplane pulled slightly left in cruise, the pilot asked the mechanic to bend the ground adjustable tab on the rudder.
Example Sentence 2
After an annual inspection the pilot checked that the ground adjustable tabs were still set correctly for hands-off flight.