2017-06-11: failure of an air conditioner compressor drive pulley (pulley) or tail rotor output wheel (wheel)

Adoption of the Amendment Accordingly, under the authority delegated to me by the Administrator, the FAA amends 14 CFR part 39 as follows: PART 39--AIRWORTHINESS DIRECTIVES 0 1. The authority citation for part 39 continues to read as follows: Authority: 49 U.S.C. 106(g), 40113, 44701. Sec. 39.13 [Amended] 0 2. The FAA amends Sec. 39.13 by adding the following new airworthiness directive (AD): 2017-06-11 Airbus Helicopters: Amendment 39-18835; Docket No. FAA- 2016-4674; Directorate Identifier 2016-SW-001-AD. (a) Applicability This AD applies to Airbus Helicopters Model EC120B helicopters with an Air Comm Corporation (Air Comm) air conditioning kit installed in accordance with supplemental type certificate (STC) No. SR00491DE, where the compressor is driven by a pulley installed aft of the rotor brake, certificated in any category. (b) Unsafe Condition This AD defines the unsafe condition as failure of an air conditioner compressor drive pulley (pulley) or tail rotor output wheel (wheel), leading to loss of tail rotor drive and helicopter control. (c) Affected ADs This AD supersedes Emergency AD 2015-24-51, Directorate Identifier 2015-SW-086-AD, dated November 27, 2015. (d) Effective Date This AD becomes effective May 8, 2017. (e) Compliance 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. (f) Required Actions (1) Before further flight, and at intervals not to exceed 25 hours time-in-service, disassemble the tail rotor drive system and remove the pulley. (i) Visually inspect the pulley splines for wear. If any splines are not straight, contain any inconsistent cross-sections end-to- end, or contain any localized material deformation or any material loss, replace the pulley before further flight. Note 1 to paragraph (f)(1)(i) of this AD: End-to-end (fore-and- aft) movement witness marks and polishing are acceptable as the pulley is allowed to slip fore and aft on the wheel per its intended function. (ii) Inspect the exposed portion of each wheel spline for cracking, scoring, metal pick-up, and wear by using Figure 1 to paragraph (f)(1)(ii) of this AD. To inspect for wear, position two 3 mm (0.118 inch) rods in all diametrically opposed splines and measure to determine whether there is a minimum of 37.3 mm (1.47 inches) across the outside diameter of the rods. If there is any cracking, scoring or metal pick-up, or if a measurement is less than 37.3 mm, replace the wheel. [GRAPHIC] [TIFF OMITTED] TR21AP17.000 (2) Within 10 days after completing the initial inspection, report the information requested in Appendix 1 to this AD by mail to the Denver Aircraft Certification Office, FAA, Technical Operations Center, 26805 East 68th Avenue, Room 214, Denver, CO 80249, attn. Richard R. Thomas; by fax to (303) 342-1088; or byemail to [email protected]. (3) Replacing the Air Comm pulley with Airbus Helicopters output flange part number C632A2158201 constitutes terminating action for this AD. (g) Special Flight Permits Special flight permits are prohibited. (h) Alternative Methods of Compliance (AMOCs) (1) The Manager, Denver Aircraft Certification Office, FAA, may approve [[Page 18694]] AMOCs for this AD. Send your proposal to: Richard R. Thomas, Aerospace Engineer, Denver Aircraft Certification Office, FAA, Technical Operations Center, 26805 East 68th Avenue, Room 214, Denver, CO 80249; fax (303) 342-1088; email [email protected]. (2) For operations conducted under a 14 CFR part 119 operating certificate or under 14 CFR part 91, subpart K, we suggest 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. (i) Additional Information (i) Air Comm Service Bulletin No. SB-EC120-111815, Revision A, dated November 20, 2015, which is not incorporated by reference, contains additional information about the subject of this AD. For service information identified in this AD, contact: Air Comm Corporation, 1575 West 124th Avenue, Westminster, CO 80234, telephone: (303) 440-4075 (during business hours) or (720) 233-8330 (after hours); email: [email protected], Web site: http://www.aircommcorp.com/contact. (ii) You may view a copy of Supplemental Type Certificate No. SR00491DE, reissued on November 24, 2014, on the Internet at http://www.regulations.gov by searching for and locating it in Docket No. FAA-2016-4674. (iii) You may review a copy of the service information at the FAA, Office of the Regional Counsel, Southwest Region, 10101 Hillwood Pkwy., Room 6N-321, Fort Worth, TX 76177. (j) Subject Joint Aircraft Service Component (JASC) Code: 6500, Tail Rotor Drive System.