2015-02-22: Repetitive visual inspections

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 removing Airworthiness Directive (AD) 2012-14-06, Amendment 39-17120 (77 FR 40479, July 10, 2012), and adding the following new AD: 2015-02-22 Rolls-Royce Corporation: Amendment 39-18090; Docket No. FAA-2011-0961; Directorate Identifier 2011-NE-22-AD. (a) Effective Date This AD is effective March 9, 2015. (b) Affected ADs This AD supersedes AD 2012-14-06, Amendment 39-17120 (77 FR 40479, July 10, 2012). (c) Applicability This AD applies to Rolls-Royce Corporation (RRC) 250-B17, -B17B, -B17C, -B17D, -B17E, -B17F, -B17F/1, -B17F/2 turboprop engines; and 250-C20, -C20B, -C20F, -C20J, -C20R, -C20R/1, -C20R/2, -C20R/4, - C20S, and -C20W turboshaft engines; with either a 3rd-stage turbine wheel, part number (P/N) 23065818, or a 4th-stage turbine wheel, P/N 23055944, installed. (d) Unsafe Condition This AD was prompted by investigations that revealed that not all 3rd-stage and 4th-stage turbine wheel blade failures were identified by the one-time inspections required by AD 2012-14-06, Amendment 39-17120 (77 FR 40479, July 10, 2012). We determined that to address the unsafe condition, repetitive inspections are [[Page 5454]] required, triggered by hours since last inspection (HSLI). We are issuing this AD to prevent failure of 3rd-stage and 4th-stage turbine wheel blades, which could cause engine failure and damage to the aircraft. (e) Compliance Comply with this AD within the compliance times specified, unless already done. After the effective date of this AD: (1) Within 1,750 HSLI, remove the affected turbine wheels and perform a visual inspection and a fluorescent-penetrant inspection (FPI) on the removed turbine wheels for cracks at the trailing edge of the turbine blades near the fillet at the rim. (2) Any time the power turbine is disassembled, perform a visual inspection and an FPI on the affected turbine wheels for cracks at the trailing edge of the turbine blades, near the fillet at the rim. (3) Thereafter, re-inspect every 1,750 HSLI. (4) Do not return to service any turbine wheels that have cracks detected. (f) Alternative Methods of Compliance (AMOCs) The Manager, Chicago Aircraft Certification Office, may approve AMOCs for this AD. Use the procedures found in 14 CFR 39.19 to make your request. (g) Related Information (1) For more information about this AD, contact John Tallarovic, Aerospace Engineer, Chicago Aircraft Certification Office, FAA, 2300 E. Devon Ave., Des Plaines, IL 60018; phone: 847-294-8180; fax: 847- 294-7834; email: john.m.tallarovic@faa.gov. (2) RRCAlert Commercial Engine Bulletin (CEB) No. CEB-A-1407, Revision 3, dated May 19, 2014, and Alert CEB No. CEB-A-72-4098, Revision 3, dated May 19, 2014 (combined into one document), which are not incorporated by reference in this AD, can be obtained from RRC, using the contact information in paragraph (g)(3) of this AD. (3) For service information identified in this AD, contact Rolls-Royce Corporation Customer Support, 450 South Meridian Street, Indianapolis, IN 46225-1103; phone: 888-255-4766 or 317-230-2720; email: royce.com">helicoptercustsupp@rolls-royce.com; Internet: www.rolls- royce.com. (4) You may view this service information at the FAA, Engine & Propeller Directorate, 12 New England Executive Park, Burlington, MA 01803. For information on the availability of this material at the FAA, call 781-238-7125. (h) Material Incorporated by Reference None.