Airworthiness Directive · Amendment 39-17005 · Tail rotor blades
Sikorsky Aircraft Corporation Helicopters
This AD applies to Sikorsky Aircraft Corporation (Sikorsky) Model S-92A helicopters with a tail rotor blade assembly (blade), part number (P/N) 92170-11000-044, -045, and -046, with a serial number with a prefix of “A111” and a number equal to or less than “-00585,” installed, certificated in any category.
We are adopting a new airworthiness directive (AD) for Sikorsky Aircraft Corporation (Sikorsky) Model S-92A helicopters. This AD was prompted by the discovery of tail rotor blade assemblies (blades) manufactured with mislocated aluminum wire mesh, leaving portions of the graphite torque tube (spar) region unprotected from a lightning strike. The actions are intended to detect mislocated blade wire mesh and to prevent spar delamination, loss of the blade tip cap during a lightning strike, blade imbalance, loss of a blade, and subsequent loss of control of the helicopter.
You are responsible for performing each action required by this AD within the specified compliance time unless it has already been accomplished prior to that time.
Within 60 days, inspect the upper and lower airfoils of each tail rotor blade to determine if the wire mesh is mislocated.
(1) Inspect by using either an eddy current inspection in accordance with paragraphs B.(1)(a) through B.(1)(o) or using the hand-sanding method and visually inspecting in accordance with paragraphs B.(2)(a) through B.(2)(d) of Sikorsky Special Service Instructions SSI No. 92-021A, Revision A, dated October 21, 2009, except you are not required to contact or report nonconforming blades to the manufacturer. If you sand and visually inspect and confirm the correct location of the wire mesh, touch-up and repaint the sanded area.
(2) If there is a blade with a mislocated wire mesh, before further flight, replace the blade with an airworthy blade.
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
