AD 47-33-01

47-33-01 DOUGLAS: (Was Mandatory Note 19 of AD-762-7.) Applies to All DC-4 and C-54 Type Aircraft Except Production DC-4 Aircraft Serial Numbers 42952, 42992, and Subsequent.

The following is to be accomplished to reduce the possibility of wear of the outboard elevator hinge parts; Inspect immediately for wear, proper installation and operation unless already accomplished, and at periods thereafter not to exceed 250 hours flight time, or in the case of Scheduled Air Carrier Operations, at each major inspection closest to 250 hours until the following mandatory rework is accomplished. (This mandatory rework shall be accomplished not later than October 15, 1947.)

(a) Each horizontal stabilizer outer hinge bracket P/N 5109899, must be reworked as follows:

(1) Line ream 0.3745-0.3755-inch diameter holes through the two lugs at each hinge point.

(2) Press in 3323406-A-2 bushings, two required, made from 9/16-inch diameter corrosion resistant steel bar, Spec. AN-QQ-S-771, Comp. FM, Cond. B., or bushing, P/N 1356866, which may be purchased from the airplane manufacturer.

(3) Machine shoulders of bushings on inside of lugs to obtain clearance for bearing in eyebolt of 0.563 inch, plus 0.005 inch and minus 0.001 inch. Minimum thickness of shoulder on each bushing after machining should not be less than 0.020 inch.

(4) Line ream hole 0.3120-0.3140 inch in diameter through bushings after pressing into hinge fitting.

(5) Remove outboard elevator hinge eyebolt assembly, P/N 2110992, and install new assembly, P/N 2328991.

(6) Reinstall elevators using 2357035-15 bolt through bushed hinge bracket and new eyebolt assembly, with 1357162 washer (two required-one under head of bolt and one under nut), AN 310-5 nut and AN 380-2-2 cotter pin.

(b) The horizontal stabilizer outer hinge bracket, P/N 5109899, was replaced in later production aircraft and on some aircraft in the field with P/N 3323406. This latter bracket incorporates a 5/16-inch bolt with eyebolt P/N 2328991, and must be reworked in accordance with parts 1, 2, 3, 4, and 6 of paragraph (a).

(Douglas Service Bulletin DC-4, No. 73 dated September 23, 1947, covers this same subject. An earlier issue of this Service Bulletin dated June 12, 1947, called for NAS 55-15 bolts in paragraph (a)(6). It is satisfactory to leave the NAS 55-15 bolts installed on airplanes reworked as per the original issued of the Service Bulletin.)