AD 78-08-09

78-08-09 GRUMMAN AMERICAN: Amendment 39-3191. Applies to Models G-164 (S/N 1 thru 400), G-164A (S/N 401 thru 1674), and G-164B (S/N 1B thru 79B) airplanes certified in all categories.

Compliance required as indicated.

To prevent collection of water in the bottom of the rudder main tubular spar (P/N A1203- 11) of the rudder assembly and the resulting corrosion, accomplish the following:

1. Within the next 50 hours in service after the effective date of this AD, unless already accomplished, perform the inspection and corrosion protection specified in Steps (1) thru (6) of Grumman American Service Bulletin No. 61 dated June 6, 1977, or equivalent.

2. Within the next 300 hours in service after compliance with paragraph (1) of this AD, and within every 300 hours in service thereafter, visually inspect the exterior of the main tubular spar for corrosion. If corrosion is noted, comply with Steps (5) and (6) of the bulletin or equivalent.

3. If repairs are required in (1)and (2) of this AD, they shall be in accordance with Advisory Circular 43.13-1A, Paragraph 74, Figure 2.7 or equivalent.

4. Upon request, with substantiating data submitted through an FAA Maintenance Inspector, the compliance times specified in this AD may be adjusted by the Chief, Engineering and Manufacturing Branch, FAA, Eastern Region.

5. Equivalent methods of compliance with this AD must be approved by the Chief, Engineering and Manufacturing Branch, FAA, Eastern Region.

This amendment is effective April 21, 1978.