Airworthiness Directive · Amendment 39-18798 · Wings
Pilatus Aircraft Ltd. Airplanes
This AD applies to PILATUS Models PC-6, PC-6-H1, PC-6-H2, PC-6/350, PC-6/350-H1, PC-6/350-H2, PC-6/A, PC-6/A-H1, PC-6/A-H2, PC-6/B-H2, PC-6/B1-H2, PC-6/B2-H2, PC-6/B2-H4, PC-6/C-H2, and PC-6/C1-H2 airplanes, all manufacturer serial numbers (MSN), including MSN 2001 through 2092, certificated in any category.
Note 1 of paragraph (c) of this AD: For MSN 2001-2092, these airplanes are also identified as Fairchild Republic Company PC-6 airplanes, Fairchild Industries PC-6 airplanes, Fairchild Heli Porter PC-6 airplanes, or Fairchild-Hiller Corporation PC-6 airplanes.
We are adopting a new airworthiness directive (AD) for Pilatus Aircraft Ltd. Models PC-6, PC-6-H1, PC-6-H2, PC-6/350, PC-6/350-H1, PC- 6/350-H2, PC-6/A, PC-6/A-H1, PC-6/A-H2, PC-6/B-H2, PC-6/B1-H2, PC-6/B2- H2, PC-6/B2-H4, PC-6/C-H2, and PC-6/C1-H2 airplanes. This AD results from mandatory continuing airworthiness information (MCAI) issued by an aviation authority of another country to identify and correct an unsafe condition on an aviation product. The MCAI describes the unsafe condition as certain combinations of the aileron counterweight and the attaching parts possibly resulting in reduced thread engagement and leading to disconnection of the aileron counterweight from the aileron. We are issuing this AD to require actions to address the unsafe condition on these products.
Unless already done, do the following actions as specified in paragraphs (f)(1) and (2) of this AD:
(1) Within the next 12 months after April 7, 2017 (the effective date of this AD) or the next time the ailerons or aileron counterweights are removed or installed, whichever occurs first, and thereafter anytime the ailerons or aileron counterweights are removed or installed, remove each aileron counterweight to inspect the type and number of washers required for the installation of a counterweight on each aileron following the accomplishment instructions of paragraphs 3.B.(2) and 3.B.(3) of Pilatus PC-6 Service Bulletin (SB) No. 57-006, dated May 13, 2016.
(2) Before further flight after the inspection required by paragraph (f)(1) of this AD, reinstall each aileron counterweight on the airplane following the accomplishment instructions of paragraph 3.B.(3) of Pilatus PC-6 SB No. 57-006, dated May 13, 2016.
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.
