Airworthiness Directive · Amendment 39-21250 · Landing gear system
Leonardo S.p.a. Helicopters
This AD applies to Leonardo S.p.a. Model AW169 helicopters, certificated in any category, with left-hand (LH) main landing gear (MLG) assembly, part number (P/N) 6F3210V00132 or P/N 6F3210V00133, with serial number (S/N) MN01 through MN84 inclusive, or right-hand (RH) MLG assembly, P/N 6F3210V00232 or P/N 6F3210V00233, with S/N MN01 to MN81 inclusive, installed. This AD does not apply to helicopters with an MLG that has been modified in accordance with Magnaghi Aeronautica S.p.A. Service Bulletin No. SB-07-2017-AW169, Issue 5, dated November 22, 2017. This AD does not apply to MLG that have a “B” on the end of the serial number.
The FAA is adopting a new airworthiness directive (AD) for Leonardo S.p.a. Model AW169 helicopters. This AD requires modifying the weight on wheels (WoW) support installation on the main landing gear (MLG). This AD was prompted by a report that an inappropriately tightened WoW support could result in a rotation of the support and improper WoW switch performance. 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 60 hours time-in-service, modify the WoW support installation as follows:
(i) Perform a short circuit connection between pin 26 of connector J343 and pin N of connector J319.
(ii) Cut the lockwire that locks the WoW microswitch and disconnect the WoW microswitch from the WoW support as depicted in Figure 1 of Leonardo Helicopters Alert Service Bulletin No. 169-047, Revision A, dated February 19, 2018 (ASB 169-047).
(iii) Unscrew the nut and remove the washer and bolt. Remove from service the nut and bolt, but replace the washer.
(iv) Remove the WoW support from the MLG and remove any paint and clean areas where indicated by Figure 2 in ASB 169-047.
(v) Apply Alodine 1132 on cleaned areas of WoW support and landing gear strut leaving a 10 mm wide strip on the WoW support for structural glue EA934 application.
(vi) Apply a 10 mm wide strip of structural glue EA934 on the WoW support and install the WoW support on the MLG using a nut, bolt, and washer.
(vii) Torque the nut to 2.5 thru 3.5 Nm. Clean any excess glue and cure the glue on the structures for one hour at 60 °C/140 °F or eight days at room temperature (22 °C-26 °C/71.6 °F-78.8 °F).
(viii) Apply liquid jointing compound AMS-S-8802 Type 2 Class B, or equivalent, to the bolt and nut, as depicted in Figure 3 of ASB 169-047 and perform a microswitch adjustment for correct operation of the microswitch.
(ix) Mark the MLG nameplate by adding the letter “B” at the end of the S/N.
(x) Remove the short circuit connection between pin 26 of connector J343 and pin N of connector J319 as performed in paragraph (e)(1)(i) of this AD.
(2) After the effective date of this AD, do not install on any helicopter a LH or RH MLG assembly with a P/N and S/N listed in paragraph (a) of this AD unless it has been modified in accordance with the requirements of paragraph (e)(1) of 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.
Aircraft
