PLT176: Balance and Trim Tabs
What code PLT176 covers, why the FAA tests it, and how to study Balance and Trim Tabs before your checkride.
Recall balance tab - purpose / operation
What this means for your checkride
A balance tab is a small surface on a control that moves opposite the control to reduce the pilot's control force. A trim tab is set by the pilot to relieve steady pressure; an anti-servo tab increases force to prevent overcontrol. All are tabs that manage control feel.
Tabs shape control forces and trim, so the FAA tests the purpose of balance, trim, servo, and anti-servo tabs.
Pilots lump all tabs together as trim. A trim tab holds a setting the pilot selects; a balance or servo tab moves automatically with the control to lighten forces, and an anti-servo tab deliberately adds force.
Where to study it
A code on your test report is an area of deficiency. An authorized instructor must review it with you and endorse that review before you take the practical test, and the examiner may revisit it during the oral. Study it until you can explain it out loud, not just recognize the answer.