Text in force at 25-153: from 25-38, effective 1 Feb 1977.
[(a) Each control system must have stops that positively limit the range of motion of each movable aerodynamic surface controlled by the system.]
(b) Each stop must be located so that wear, slackness, or take-up adjustments will not adversely affect the control characteristics of the airplane because of a change in the range of surface travel.
(c) Each stop must be able to withstand any loads corresponding to the design conditions for the control system.
41 FR 55466 · Source