Airworthiness Directive · Amendment 39-10026 · Sikorsky Aircraft Corporation Model S- 61A, D, E, L, N, NM, R, and V Helicopters
Sikorsky Aircraft Corporation Model S- 61A, D, E, L, N, NM, R, and V Helicopters
Model S-61A, D, E, L, N, NM, R, and V helicopters, certificated in any category, with a main rotor blade assembly (blade), part number (P/N) S6115-20501 or P/N 61170-20201, installed, having one of the following four-digit or eight-digit serial numbers: 1282-1554 3305-3106 2183 3317-3115 2380-2498 3343-3147 2495 3343-3648 2500 3364-3180 2520 3451-3239 2521 3491-3278 2644 3499-3936 2673 3511-3293 2716-2683 3512-3292 2721 3517-3311 2751 3525-3310 2781-2644 3637-3459 2800-2671 3694-3481 2817 3748-3543 2819 3752-3527 2839 3753-3528 2883 3840-3620 2919-2771 3966-3737 3008 4216-4392 3016-2850 4787-4793 3019 4800-4794 3138 4835-4790 3168-3585 5484-5363 3192-2999 5974-5816 3215-3012 5981-5813 3216-3023 7069-6583 3242-3044 7779-7033 3249-3052 8099-8054 3250-3043
This amendment supersedes an existing priority letter airworthiness directive (AD), applicable to Sikorsky Aircraft Corporation Model S-61A, D, E, L, N, NM, R, and V helicopters, that currently requires inspecting certain main rotor blade assemblies (blades) to determine if a blade has a blade trailing edge pocket assembly (pocket assembly) that was anodized by Poly-Metal Company during a specified time period, and if so, replacing it with an airworthy blade. This amendment requires the same actions as the existing AD, but corrects two serial numbers in the list of the applicable blades. This amendment is prompted by the manufacturer's issuance of a service bulletin with a revised list of blade serial numbers. The actions specified by this AD are intended to prevent disbonding and separation of portions of the blade, subsequent excessive vibrations, and loss of control of the helicopter.
The aircraft, engines and makers this AD names, by the model designations in its text. A model listed here may still be outside the AD's serial ranges.
Aircraft
