AD 2020-05-23 Airworthiness Directives; Airbus Helicopters

This AD becomes effective April 24, 2020.

(1) The Manager, Safety Management Section, Rotorcraft Standards Branch, FAA, may approve AMOCs for this AD. Send your proposal to: Matt Fuller, Senior Aviation Safety Engineer, Safety Management Section, Rotorcraft Standards Branch, FAA, 10101 Hillwood Pkwy., Fort Worth, TX 76177; telephone 817-222-5110; email 9-ASW-FTW-AMOC-Requests@faa.gov. (2) For operations conducted under a 14 CFR part 119 operating certificate or under 14 CFR part 91, subpart K, the FAA suggests that you notify your principal inspector, or lacking a principal inspector, the manager of the local flight standards district office or certificate holding district office, before operating any aircraft complying with this AD through an AMOC.

The subject of this AD is addressed in European Union Aviation Safety Agency (previously European Aviation Safety Agency) (EASA) AD No. 2018-0282, dated December 19, 2018. You may view the EASA AD on the internet at https://www.regulations.gov in Docket No. FAA-2019-0882.

Within 110 hours time-in-service, remove the sealing compound and inspect each screw on the RH and LH rear attachment fitting by identifying the number of threads “F” that extend beyond the nut as shown in Detail “B” of Figure 2 of Airbus Helicopter Alert Service Bulletin No. AS332-53.02.04, Revision 0, dated November 21, 2018 (ASB AS332-53.02.04). (1) If there are 2 or less threads on each of the four screws; or there are 3 or more threads on any screw with a thread height “H” less than 5 mm (0.196 in), before further flight, apply a sealing compound on the nuts, and convex and concave washers. (2) If there are 3 or more threads on any screw with a thread height “H” of 5 mm (0.196 in) or more, before further flight, do the following, and for more than one screw, do one at a time while working in a cross pattern: Remove from service the nut; and remove the screw from the helicopter and measure the length “L” of the screw as shown in Detail “D” of Figure 2 of ASB AS332-53.02.04. (i) If any washers are bent or corroded, before further flight, remove from service the washers. (ii) If the length “L” measurement is less than or equal to 59.3 mm (2.334 in) for each screw removed as required by paragraph (e)(2) of this AD, visually inspect the screw for corrosion and cracks. (A) For each screw with corrosion or a crack, before further flight, replace the screw with an airworthy screw. (B) For any screw with no corrosion or cracks, before further flight, re-install the screw and washers. Install a new nut and apply sealant. (iii) If the length “L” measurement is greater than 59.3 mm (2.334 in) for any screw removed as required by paragraph (e)(2) of this AD, before further flight, replace the rear attachment fitting that the screw was removed from and its set of four screws, washers, and nuts, and apply sealant as shown in Figures 2 and 3 of ASB AS332-53.02.04.

This AD defines the unsafe condition as elongation of the attachment screws and loss of tightening torque of the nut. This condition could result in structural failure of an MGB attachment fitting, detachment of an MGB suspension bar, and subsequent loss of control of the helicopter.