14 CFR § 25.405 - Secondary control system.

§ 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.