14 CFR 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|
|*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).|
|Push-pull||To be chosen by applicant.|
*Limited to flap, tab, stabilizer, spoiler, and landing gear operation controls.