From MIL-F- 8785C (November 1980):
The change in roll control force required to maintain attitude and sideslip shall not exceed 10 lbs for at least 5 seconds following:
1. Complete or partial loss of any function of the augmentation system following a single failure.
2. Failure induced transient motions and trim changes either immediately after failure or upon subsequent transfer to alternate control modes.
3. Configuration changes required or recommended following failure.
From FAR part 23:
A maximum of 30 lbs stick force ( 60 lbs control wheel force) is allowed for temporary application.
A maximum of 5 lbs stick or control wheel force is allowed for
prolonged application.
From FAR part 25:
A maximum of 60 lbs control wheel force is allowed for temporary application.
A maximum of 5 lbs control wheel force is allowed for prolonged application.
See Graphic