Airworthiness Directive · Amendment 39-17705 · Nose landing gear attach section
AgustaWestland S.p.A. (Type Certificate Previously Held by Agusta S.p.A.) Helicopters
This AD applies to AgustaWestland S.p.A. (Agusta) Model AB139 and AW139 helicopters, serial number 31005, 31006, 31008 through 31157, 31201 through 31398, 31400 through 31412, 31414, 31416, 31418, 31419, 31421, 31425, 31426, 31428, 31432, 31440, 41001 through 41023, 41201 through 41275, 41277 through 41286, 41288, 41293, 41300, 41301, 41303, 41307, 41308, and 41310, with a nose landing gear (NLG) pin part number 1661-0001 installed, certificated in any category.
We are adopting a new airworthiness directive (AD) for certain AgustaWestland S.p.A. (Agusta) Model AB139 and AW139 helicopters. This AD requires inspecting the nose landing gear (NLG) pin installations for incorrect assembly. This AD is prompted by reports of incorrectly installed pins discovered on in-service aircraft. These actions are intended to detect incorrectly installed pins, which could result in collapse of the NLG during taxi or landing.
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 50 hours time-in-service:
(1) Inspect the NLG pin installations on the left and right arms to determine whether the bolt (item 2), washer (item 3) under the bolt head, washer (item 4) between the NLG arm and pin, pin (item 5), washer (item 6) under the nut, nut (item 7), and cotter pin (item 8) are installed as depicted in Figure 1 of Agusta Bollettino Tecnico (BT) No. 139-306, dated December 12, 2012 (BT 139-306).
(2) If any part is not installed as depicted in Figure 1 of BT 139-306, before further flight, disassemble items 2 through 8 and accomplish the following:
(i) Inspect each bolt and nut for corrosion. If there is any corrosion on a bolt or nut, remove the bolt and nut from service.
(ii) Inspect each pin for corrosion and damage. If there is any corrosion or damage:
(A) Remove the corrosion and damage with an abrasive stone or glass fiber brush.
(B) Measure the pin diameter. If the pin diameter is less than 25.36 mm (0.998 inch), remove the pin from service.
(iii) Inspect each pin for a crack. If there is a crack, remove the pin from service.
(iv) Dye penetrant inspect the pin flange for a crack. If there is a crack, remove the pin from service.
(3) If items 2 through 8 are installed as depicted in Figure 1 of BT 139-306, inspect each bolt head and nut for corrosion. If there is any corrosion on a bolt head or nut, before further flight, remove the bolt or nut from service.
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.
