Airworthiness Directive · Amendment 39-21387 · Flight controls
Pilatus Aircraft Ltd. Airplanes
This AD applies to Pilatus Aircraft Ltd. Model PC-12/47E airplanes, all serial numbers (S/Ns), certificated in any category.
The FAA is adopting a new airworthiness directive (AD) for Pilatus Aircraft Ltd. (Pilatus) Model PC-12/47E airplanes. This AD was prompted by mandatory continuing airworthiness information (MCAI) originated 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 inboard flap fairings aft (IFFAs) having an incorrect shape, which may result in chafing between the IFFA and the associated front inboard tension rod. This AD requires an inspection of the IFFAs for the correct shape and chafing between the IFFA and the associated front inboard tension rod, with corrective action as necessary. This condition could lead to failure of the inboard flap drive arm with consequent asymmetric flap extension, resulting in reduced control of the airplane. The FAA is issuing this AD to address the unsafe condition on these products.
(1) For airplanes with a S/N 1576 and higher, unless already done, within 100 hours time-in-service (TIS) after the effective date of this AD or within 6 months after the effective date of this AD, whichever occurs first, inspect the left-hand (LH) and right-hand (RH) IFFAs for correct shape and clearance with the LH and RH tension rods by following step 3.B.(1) and Figures 2 and 3 of the Accomplishment Instructions—Aircraft in Pilatus PC-12 Service Bulletin No: 27-026, dated July 10, 2019 (Pilatus SB 27-026).
(i) If the shape of the LH or RH IFFA is incorrect or if the clearance between the IFFA and the tension rod is less than 5 mm (0.2 inch), before further flight, modify the IFFA and inspect the tension rods for chafing by following section 3.C. of the Accomplishment Instructions—Aircraft in Pilatus SB 27-026.
(ii) If the shape of the LH and RH IFFAs is correct and the clearance between the IFFA and the tension rod is at least 5 mm (0.2 inch), before further flight, inspect the front inboard LH and RH tension rods for chafing by following step 3.C.(12)(a) of the Accomplishment Instructions—Aircraft in Pilatus SB 27-026. If the LH or RH tension rod has any chafing, before further flight, replace the tension rod by following step 3.C.(12)(b) of the Accomplishment Instructions—Aircraft in Pilatus SB 27-026.
(2) For airplanes with a S/N 1001 through S/N 1575, inclusive, that have a tension rod part number (P/N) 527.52.12.135 installed, unless already done, within 100 hours TIS after the effective date of this AD or within 6 months after the effective date of this AD, whichever occurs first, inspect the front inboard LH and RH tension rods for chafing by following step 3.C.(12)(a) of the Accomplishment Instructions—Aircraft in Pilatus SB 27-026. If the LH or RH tension rod has any chafing, before further flight, replace the tension rod by following step 3.C.(12)(b) of the Accomplishment Instructions—Aircraft in Pilatus SB 27-026.
(3) For all Model PC-12/47E airplanes, as of the effective date of this AD, do not install on any airplane an LH IFFA P/N 557.52.12.223, RH IFFA P/N 557.52.12.224, or tension rod P/N 527.52.12.135 unless the part has been inspected and all corrective actions have been taken as required by this AD.
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.
