Text in force at 23-63: from 23-7, effective 14 Sep 1969.
[If speed control devices (such as spoilers and drag flaps) are incorporated for use in enroute conditions--
(a) The airplane must be designed for the symmetrical maneuvers and gusts prescribed in Secs. 23.333, 23.337, and, 23.341, and the yawing maneuvers and lateral gusts in Secs. 23.441 and 23.443, with the device extended at speeds up to the placard device extended speed; and
(b) If the device has automatic operating or load limiting features, the airplane must be designed for the maneuver and gust conditions prescribed in paragraph (a) of this section at the speeds and corresponding device positions that the mechanism allows.]
34 FR 13089 · Source