Airworthiness Directive · Amendment 39-21169 · Main rotor gearbox
PZL Swidnik S.A. Helicopters
This AD applies to PZL Swidnik S.A. (PZL) Model W-3A helicopters, with a serial number up to 3X.10.12 inclusive, certificated in any category, with a main transmission (Main XMSN) case, part number (P/N) 64.21.0105 or P/N 64.22.0161, installed on a WR-3 Main XMSN P/N 64.21.3000 or P/N 64.21.4000.
The FAA is adopting a new airworthiness directive (AD) for certain PZL Swidnik S.A. (PZL) Model W-3A helicopters. This AD requires repetitive inspections of the main transmission (Main XSMN) case for a crack, and depending on the inspection outcome, removing the WR-3 Main XSMN from service before further flight. This AD was prompted by a report of cracks in a Main XSMN case. The actions of this AD are intended to address an unsafe condition on these products.
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.
(1) Within 5 hours time-in-service (TIS), using a light source and mirror, and paying particular attention to the area above the Main XSMN mounting flange as shown in Attachment 1, Sketch 2 LH side and Sketch 2 RH side of Wytwórnia Sprzętu Komunikacyjnego “PZL-Świdnik” Spółka Akcyjna Mandatory Bulletin No. BO-37-18-294, dated April 12, 2018 (BO-37-18-294), visually inspect the Main XMSN case for a crack and indications of a crack. For purposes of this inspection, indications of a crack may be indicated by paint coat chipping or cracking, a surface scratch, or an oil leak.
(i) If there is a crack, before further flight, remove from service the WR-3 Main XMSN.
(ii) If there is any indication of a crack, before further flight, clean the Main XMSN case with a cotton cloth and washing or degreasing agent (extraction naphtha or equivalent), and using a 5X or greater power magnifying glass, visually inspect the area for a crack.
(A) If there is a crack, before further flight, remove from service the WR-3 Main XMSN.
(B) If there is no a crack, before further flight, apply white chalk on the area as described in paragraph (e)(1) of this AD and perform a powerplant ground run for 15 minutes with engines running at ground idle rating. After shutting down, either inspect the white chalk area for discoloration of the chalk or dye penetrant inspect the area for a crack. If the chalk is discolored or there is a crack, before further flight, remove from service the WR-3 Main XMSN.
Note 1 to paragraph (e)(1)(ii)(B) of this AD: Wytwórnia Sprzętu Komunikacyjnego “PZL-Świdnik” Spółka Akcyjna service information refers to a dye penetrant inspection as a color penetrant inspection.
(2) Thereafter following paragraph (e)(1) of this AD, at intervals not to exceed 25 hours TIS, do the actions required by paragraph (e)(1) of this AD.
