76-18-12 GRUMMAN AMERICAN AVIATION CORPORATION: Amendment 39- 2721. Applies to Model G-1159 airplanes certificated in all categories, serial numbers 1 through 154 and 775.
Compliance required within the next 100 hours time in service after the effective date of this AD, unless already accomplished.
To detect loose terminal connections at the generator terminal boards and to prevent the loosening of these connections, accomplish the following:
1. Modify each engine electrical junction box to provide an access hole for inspecting the two generator terminal boards and the eight associated wiring connections. Grumman American Aircraft Service Change No. 203 Amendments 1 and 2 provide the information for accomplishing this modification.
2. If the inspection reveals that all generator terminals are secure, i.e., that all lock washers are compressed and torque stripes not broken, the connections are satisfactory.
3. Reinspect in accordance with A.S.C. No. 203 Amendments 1 and 2 in intervals of 300 hours time in service until the basic A.S.C. No. 203 has been accomplished.
4. If the lock washer on any terminal is found not to be compressed, or evidence of arcing at any connection is noted, the affected engine shall be removed and the basic A.S.C. No. 203 accomplished to the corresponding engine junction box.
5. The reinspection procedure must continue for the remaining engine junction box until the basic A.S.C. No. 203 has been accomplished. This service change requires the removal of a plain nut, a plain washer, and lockwasher from each generator terminal, and replacing them with a self-locking nut and a plain washer.
6. Compliance with the basic A.S.C. No. 203 must be accomplished at the next engine removal, if not done prior to that time.
This Airworthiness Directive may be accomplished by any other means approved by the Chief, Engineering and Manufacturing Branch of the Southern Region, Atlanta, Georgia.
This amendmentbecomes effective September 22, 1976.