2016-22-11: HPT stage 2 nozzle segments

Adoption of the Amendment Accordingly, under the authority delegated to me by the Administrator, the FAA amends part 39 of the Federal Aviation Regulations (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 removing airworthiness directive (AD) 2013-02-06, Amendment 39-17327 (78 FR 5710, January 28, 2013) and adding the following new AD: 2016-22-11 Engine Alliance: Amendment 39-18700; Docket No. FAA-2012- 1293; Directorate Identifier 2012-NE-45-AD. (a) Effective Date This AD is effective November 16, 2016. (b) Affected ADs This AD replaces AD 2013-02-06, Amendment 39-17327 (78 FR 5710, January 28, 2013). (c) Applicability This AD applies to all Engine Alliance GP7270 and GP7277 turbofan engines with a high-pressure turbine (HPT) stage2 nozzle segment, part number (P/N) 2101M24G01, 2101M24G02, 2101M24G03, 2101M24G04, 2101M24G05, or 2101M24G06, installed. (d) Unsafe Condition This AD was prompted by a report of inadequate cooling of the HPT stage 1 shroud and stage 2 nozzle, leading to damage to the HPT stage 2 nozzle, burn-through of the turbine case, and in-flight shutdown. We are issuing this AD to prevent HPT stage 2 nozzle failure, uncontrolled fire, in-flight shutdown, and damage to the airplane. (e) Compliance Comply with this AD within the compliance times specified, unless already done. (1) Perform a 360 degree borescope inspection of the HPT stage 1 shroud and stage 2 nozzle as follows: (i) For engines with nozzles installed at a shop visit that did not include full engine overhaul, borescope inspect the HPT stage 1 shroud and stage 2 nozzle as follows: (A) If the nozzle has fewer than 1,050 cycles-since-new (CSN) or cycles-since-repair (CSR) on the effective date of this AD,before the nozzle has accumulated 1,100 CSN or CSR. (B) If the nozzle has 1,050 or more CSN or CSR on the effective date of this AD, within the next 50 cycles. (ii) For all other engines, borescope inspect the HPT stage 1 shroud and HPT stage 2 nozzle as follows: (A) If the nozzle has fewer than 1,450 CSN or CSR on the effective date of this AD, before the nozzle has accumulated 1,500 CSN or CSR. (B) If the nozzle has 1,450 or more CSN or CSR on the effective date of this AD, within the next 50 cycles. (iii) Thereafter, repetitively borescope inspect the HPT stage 1 shroud and stage 2 nozzle as follows: (A) For engines with HPT stage 2 nozzle segments, P/N 2101M24G01, 2101M24G02, or 2101M24G03, within every 150 additional cycles-in-service (CIS). (B) For engines with HPT stage 2 nozzle segments, P/N 2101M24G04, 2101M24G05, or 2101M24G06, within every 300 additional CIS. (2) If any burn holes are detected through the surface of the nozzle or if the shroud is distorted radially inward with evidence of blade tip rubs, remove the HPT stage 1 shroud and HPT stage 2 nozzle from service before further flight. [[Page 75686]] (f) Mandatory Terminating Action Replace HPT stage 2 nozzle segments, P/N 2101M24G01, 2101M24G02, 2101M24G03, 2101M24G04, 2101M24G05, and 2101M24G06, at the next piece-part exposure, with parts eligible for installation. (g) Definition For the purpose of this AD, piece-part exposure is when the HPT stage 2 nozzle is removed from the engine and completely disassembled. (h) Alternative Methods of Compliance (AMOCs) The Manager, Engine Certification Office, FAA, may approve AMOCs for this AD. Use the procedures found in 14 CFR 39.19 to make your request. You may email your request to: [email protected]. (i) Related Information For more information about this AD, contact Martin Adler, Aerospace Engineer, Engine & Propeller Directorate, FAA, 1200 District Avenue, Burlington, MA 01803;phone: 781-238-7157; fax: 781-238-7199; email: [email protected]. (j) Material Incorporated by Reference None.