AD 2009-07-53 Airworthiness Directives; Sikorsky Aircraft Corporation Model S-92A Helicopters

Models named: S-92A. Read the applicability below — it usually turns on serial or part numbers too.

Model S-92A helicopters with a main gearbox housing assembly, part number (P/N) 92351-15110-042, -043, or -044, that is not marked with “TS-062-01” near the P/N, certificated in any category.

Required before further flight, unless accomplished previously. To prevent failure of a main gearbox filter bowl assembly mounting stud (stud), which could result in rapid loss of oil, failure of the main gearbox, and subsequent loss of control of the helicopter, accomplish the following: (a) Remove the titanium studs by following the Accomplishment Instructions in Sikorsky Alert Service Bulletin No. 92-63-014, Rev. A, dated March 20, 2009 (ASB), paragraph 3.A. Note: Figure 1 of the ASB contains guidance for removal and installation of the studs. (b) Visually inspect the tapped holes and the main gearbox housing lockring counterbore for damage. If you find damage in the tapped holes or in the main gearbox housing lockring counterbore, contact the Boston Aircraft Certification Office for an approved repair. (c) Install steel studs and mark the main gearbox housing as “TS-062-01” near the P/N by following the Accomplishment Instructions in the ASB, paragraph 3.C. (d) To request a different method of compliance or a different compliance time for this AD, follow the procedures in 14 CFR 39.19. Contact the Manager, Boston Aircraft Certification Office, Engine and Propeller Directorate, FAA, Attn: Kirk Gustafson, Aviation Safety Engineer, 12 New England Executive Park, Burlington, MA 01803, telephone (781) 238-7190, fax (781) 238-7170, for information about previously approved alternative methods of compliance. (e) Special flight permits will not be issued. (f) Remove and replace the studs by following the specified portions of Sikorsky Alert Service Bulletin No. 92-63-014, Rev. A, dated March 20, 2009. The Director of the Federal Register approved this incorporation by reference in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies may be obtained from Sikorsky Aircraft Corporation, Attn: Manager, Commercial Technical Support, Mailstop s581a, 6900 Main Street, Stratford, CT, telephone (203) 383-4866, e-mail address tsslibrary@sikorsky.com, or at http://www.sikorsky.com. Copies may be inspected at the FAA, Office of the Regional Counsel, Southwest Region, 2601 Meacham Blvd., Room 663, Fort Worth, Texas or at the National Archives and Records Administration (NARA). For information on the availability of this material at NARA, call 202-741-6030, or go to: http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html. (g) This amendment becomes effective on April 27, 2009, to all persons except those persons to whom it was made immediately effective by Emergency AD 2009-07-53, issued March 23, 2009, which contained the requirements of this amendment. Issued in Fort Worth, Texas, on April 9, 2009. Mark R. Schilling, Acting Manager, Rotorcraft Directorate, Aircraft Certification Service. [FR Doc. E9-9301 Filed 4-24-09; 8:45 am] BILLING CODE 4910-13-P