63-21-04 LOCKHEED: Amdt. 625 Part 507 Federal Register October 2, 1963. Applies to All Models L-18 and PV-1 Airplanes Equipped With Spartan Electrically Actuated Elevator Trim Tabs.
Compliance required as indicated.
To prevent runaway operation of the electrically operated trim tab actuators, accomplish the following:
(a) Within 30 hours' time in service after the effective date of this AD unless already accomplished, electrically deactivate the elevator trim tab.
(b) Any tab deactivated may be reactivated when one of the following has been accomplished:
(1) On any Lockheed Model 18 airplane with Spartan electrically actuated elevator trim tab, the trim tab installation is made in accordance with STC SA2-183.
(2) An FAA approved modification to the speed and limits of actuation is accomplished. Modifications must be approved by the Chief of an FAA Engineering and Manufacturing Branch.
This directive effective November 1, 1963.
Revised January 10, 1964.