Airworthiness Directive · Amendment 39-21456 · Tail stabilizer
Leonardo S.p.a. Helicopters
This AD applies to Leonardo S.p.a. Model AW189 helicopters, certificated in any category.
The FAA is adopting a new airworthiness directive (AD) for Leonardo S.p.a. (Leonardo) Model AW189 helicopters. This AD was prompted by two reported failures of the tail plane installation forward bolts (bolts). This AD requires inspecting the bolts and depending on the results of those inspections, removing certain parts from service or installing a tail plane retromod. This AD also requires torqueing certain part-numbered nuts, inspecting bolts and nuts for wear, and depending on the results of those inspections, removing parts from service. The FAA is issuing this AD to address the unsafe condition on these products.
(1) For helicopters without a tail plane installation retromod part number (P/N) 8G5510P00511 (tail plane retromod) installed, before further flight and thereafter before each flight, inspect each forward attachment bolt (bolt) P/N 8G5510A06251 and 8G5510A05951 for a missing bolt head, breakage, and correct installation as depicted in Figure 12 of Leonardo Helicopters Emergency Alert Service Bulletin No. 189-177, Revision A, dated February 28, 2018 (EASB 189-177). If there is a missing bolt head, a broken bolt, or an incorrectly installed bolt, before further flight, remove the bolt from service and install the tail plane retromod by following the Accomplishment Instructions, Part II, paragraphs 3.1 through 3.33 of EASB 189-177, except you are not required to discard parts and where EASB 189-177 specifies contacting Leonardo PSE for corrective action, the action must be accomplished using a method approved by the Manager, International Validations Branch, FAA. The Manager's approval letter must specifically refer to this AD.
(2) For helicopters with a tail plane retromod installed in accordance with Leonardo Helicopters Service Bulletin No. 189-130, dated January 30, 2017, and for helicopters with serial number 49046, 49053, 89008, 89009, 92007, or 92008, within 10 hours time-in-service (TIS) after the effective date of this AD, loosen and then torque each nut P/N MS17825-7 (nut) to 15 to 20 Nm (11 to 14.75 ft-lbs), and install a cotter pin and lockwire each nut on the adjustable rod assembly P/N 4F5510A00232, as depicted in Figure 7, Detail N Step 6.5 and Figure 9, Detail P Step 7.9 of EASB 189-177.
(3) Within 10 hours TIS after installing a tail plane retromod, within 10 hours TIS after complying with paragraph (g)(2) of this AD, or within 10 hours TIS after the effective date of this AD, whichever occurs later, and thereafter at intervals not to exceed 50 hours TIS, do the following:
(i) Determine the torque of each nut.
(ii) If the torque is less than 15 Nm (11 ft-lbs) or more than 20 Nm (14.75 ft-lbs), before further flight, remove the bolt and nut and inspect for wear. If there is any wear on the bolt or nut, before further flight, remove the bolt and nut from service.
