Federal Aviation Regulations
Sec. 25.405 — Secondary control system.
Secondary controls, such as wheel brake, spoiler, and tab controls, must be designed for the maximum forces that a pilot is likely to apply to those controls. The following values may be used:Pilot Control Force Limits (Secondary Controls)
| Control | Limit pilot forces |
|---|---|
| Miscellaneous: | |
| *Crank, wheel, or lever | ((1 + R) / 3) × 50 lbs., but not less than 50 lbs. nor more than 150 lbs. (R=radius). (Applicable to any angle within 20° of plane of control). |
| Twist | 133 in.–lbs. |
| Push-pull | To be chosen by applicant. |
*Limited to flap, tab, stabilizer, spoiler, and landing gear operation controls.
NEXT: Sec. 25.407 - Trim tab effects.
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