76-08-02 R2 CESSNA: Amendment 39-2582 as amended by Amendment 39-2608 is further amended by Amendment 39-4540. Applies to the following models of airplanes if equipped with strobe lights installed in the wing tip fuel tank nose cap, except those airplanes having Symbolic Displays P/Ns 30-0005, 30-0199-1, 30-0199-2, 30-0199-3, 30-0329, 31-0725-1, and 701133-1, Whelen Engineering Company, Inc., P/N A430, and Grimes Manufacturing Company (Grimes) P/Ns 30-0515-5, 30-1172-1, 30-1172-5, 30-0531-1, and 30-0467-5 strobe lights:
Models 310, 310A, Military U-3A, 310B, 310C, 310D, 310E, Military U-3B, 310F, 310G, 310H, E310H, 310I, 310J, 310J-1, E310J, 310K, 310L, 310N, 310P, T310P, 310Q, T310Q, 310R, T310R; 320, 320-1, 320A, 320B, 320C, 320D, 320E, 320F; 340; 401, 401A, 401B; 402, 402A, 402B; 411, 411A; 414; and 421, 421A, and 421B airplanes.
Compliance: Required as indicated, unless already accomplished.
To preclude wing fuel tip tank nose cap explosions, within the next 100hours' time in service after the effective date of this AD, accomplish the following:
A) Visually inspect the strobe lights in the tip tank nose cap area to determine whether Grimes P/N 30-0515-1 strobe light or any other strobe lights other than those excepted above are installed. On those airplanes where Grimes P/N 30-0515-1 strobe lights are installed, determine if the strobe lights have been modified by installing Grimes P/Ns 31-1723-5 or 30-1171-1 cover plates. These cover plates may be identified by the presence of two quench tubes protruding into the light assembly from the end plate.
B) On those airplanes having unmodified Grimes P/N 30-0515-1 strobe lights, or strobe lights other than those excepted above, deactivate the strobe light system by installing a guard over the switch and/or by pulling and blocking the circuit breaker so that it cannot be inadvertently reset or by any other suitable means.
C) Systems having unmodified Grimes P/N 30-0515-1 strobe lights may be reactivated upon the installation of Grimes P/Ns 31-1723-5 or 30-1171-1 cover plates in accordance with Cessna Service Letter ME75-16, dated July 11, 1975, or later approved revisions.
D) Do not reactivate strobe light assemblies, other than Grimes P/N 30-0515-1 strobe lights modified per Paragraph C, until data showing the strobe lights are explosion proof have been submitted to and approved by the Chief, Engineering and Manufacturing Branch, or Division of the FAA Region issuing the original light approval.
Amendment 39-2582 became effective April 23, 1976, and superseded Amendment 39-2103, AD 75-05-08.
Amendment 39-2608 became effective May 20, 1976.
This Amendment 39-4540 becomes effective January 31, 1983.