AD 64-16-04 ACTIVE

64-16-04 LOCKHEED: Amdt. 768 Part 507 Federal Register July 21, 1964. Applies to Models 188A and 188C Series Aircraft.

Compliance required within 425 hours' time in service after the effective date of this AD, unless accomplished within the last 3,575 hours' time in service, and thereafter at intervals not to exceed 4,000 hours' time in service from the last inspection.

As a result of excessive wear and cracks in the aileron control system push-pull tubes, accomplish the following:

(a) Visually inspect the wear pattern on the eight aileron push-pull tubes located aft of the wing rear spar, P/N's 810863-1, 810865-1, and 807742-1, and measure the maximum wear from the outside surface of the tube to the depth of the wear mark. When the visual inspection reveals indications of a crack or a lengthwise groove in the push-pull tube, inspect for cracks by using a magnetic particle inspection method or an equivalent approved by the Chief, Aircraft Engineering Division, FAA Western Region.

(b) Manually spin and visually inspect all of the aileron push-pull tube support rollers for freedom of rotation and for flat spots.

(c) Following the inspections of (a) and (b) accomplish the following before further flight, except that the aircraft may be ferried in accordance with the provisions of CAR 1.76 to the base at which the repairs or replacements are to be accomplished:

(1) Replace cracked aileron push-pull tubes with new parts of the same part number or an FAA approved equivalent. Replace aileron push-pull tubes P/N 810865-1 with more than 0.006 inch of wear, P/N 810863-1 with more than 0.008 inch of wear, and P/N 807742-1 with more than 0.012 inch of wear with new parts of the same part number or an FAA approved equivalent.

(2) Replace aileron push-pull tube support rollers which do not rotate freely or which have a flat spot with new rollers of the same part number or an FAA approved equivalent.

(3) When push-pull tubes orpush-pull tube support rollers are replaced in accordance with (c)(1) or (c)(2), adjust the clearance between the aileron push-pull tubes and their support rollers in accordance with Section 2.B.(4) of Lockheed Alert Service Bulletin 88/SB-607.

(d) Upon request of the operator, an FAA maintenance inspector, subject to prior approval of the Chief, Aircraft Engineering Division, FAA Western Region, may adjust the repetitive inspection intervals specified in this AD to permit compliance at an established inspection period of the operator if the request contains substantiating data to justify the increase for such operator.

(Lockheed telegram to operators FS/265688-W dated September 24, 1963, and Lockheed Service Bulletin 88/SB-607 pertain to this same subject.)

This directive effective August 21, 1964.

Revised March 2, 1965.