# Reducing Control Forces

> Aerodynamic balancing methods to assist the pilot.

- **Subject:** 081 — Principles of Flight
- **Section:** 081-05 — Control
- **Topic code:** 081-05-06
- **Last reviewed:** 2026-04-01
- **Author:** Pablo Asensio Martínez
- **HTML version:** https://pilotsyllabus.com/en/principles-of-flight/control/means-to-reduce-control-forces/

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## The Problem
As aircraft size and speed increase, the force required to deflect a control surface becomes too great for a pilot to handle manually.

## Aerodynamic Balance
Methods to use airflow to help move the control.

1.  **Horn Balance**: A portion of the control surface (the "horn") projects ahead of the hinge line at the tip.
    *   When deflected, the horn produces a force that assists the movement.
    *   Also acts as a Mass Balance weight.

2.  **Inset Hinge**: The hinge is set back into the control surface.
    *   Part of the surface area is ahead of the hinge line, reducing the moment arm of the aerodynamic load.

3.  **Balance Tab**: (Covered in Trimming). Moves opposite to the control surface.

4.  **Frise Aileron**: (Covered in Roll). The nose of the aileron projects into the airflow, assisting the deflection (and adding drag).

## Artificial Feel
In fully powered controls (hydraulics/FBW), the pilot feels *no* aerodynamic load.
*   **Springs/Q-Feel**: Artificial resistance must be added so the pilot receives feedback proportional to deflection and airspeed.

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Free study notes from pilotsyllabus.com. Not a substitute for training at an approved ATO.