AD 2001-01-04 Airworthiness Directives; Sikorsky Aircraft Corporation Model S-76A, S-76B, and S-76C Helicopters

Models named: S-76A, S-76B, S-76C. Read the applicability below — it usually turns on serial or part numbers too.

Model S-76A, S-76B, and S-76C helicopters up to and including serial number 760513 with positioning rod assembly (rod assembly), part number (P/N) 1945E-31A or 2071-31, or side brace rod end (rod end), P/N 1945E-235 or 2071-235, installed, certificated in any category. Note 1: This AD applies to each helicopter identified in the preceding applicability provision, regardless of whether it has been otherwise modified, altered, or repaired in the area subject to the requirements of this AD. For helicopters that have been modified, altered, or repaired so that the performance of the requirements of this AD is affected, the owner/operator must request approval for an alternative method of compliance in accordance with paragraph (e) of this AD. The request should include an assessment of the effect of the modification, alteration, or repair on the unsafe condition addressed by this AD; and if the unsafe condition has not been eliminated, the request should include specific proposed actions to address it.

Required as indicated, unless accomplished previously. To detect corrosion of the threaded joint in the rod assembly and prevent a collapse of the landing gear and subsequent loss of control of the helicopter during landing, accomplish the following: (a) Within 14 days, inspect the rod assembly and rod end for corrosion in accordance with Section 2., Accomplishment Instructions, in BF Goodrich Service Bulletin No. 76A-32-03, Revision 1, dated September 15, 2000 (SB), except that scrapping of corroded parts is not required. Replace any part that is corroded with an airworthy part before further flight. (b) Within 90 days, if the rod assembly and rod end were inspected and reassembled in accordance with BF Goodrich Component Maintenance Manual with Illustrated Parts List, 1945/2071 Series Main Landing Gear, No. 32-10-01, (formerly titled Cleveland Pneumatic Maintenance Manual 32-10-01), Revision 4, dated December 15, 1994, within the past 24 months, inspect the rod assembly and rod end in accordance with Section 2. of the SB. Scrapping of corroded parts is not required. Replace any part that is corroded with an airworthy part before further flight. (c) At intervals not to exceed 90 days, for rod ends that are not reassembled with Mastinox sealant or reassembled with Mastinox sealant but without cadmium plate restoration, inspect the rod assembly and rod end for corrosion in accordance with the Section 2. of the SB, except that scrapping of corroded parts is not required. Replace any part that is corroded with an airworthy part before further flight. (d) At intervals not to exceed 12 months or 1,500 hours time-in-service, whichever occurs first, for rod ends assembled with Mastinox sealant and cadmium plate restoration or for rod ends reassembled with Mastinox but that did not previously require rework due to corrosion, inspect the rod assembly and rod end for corrosion in accordance with the Section 2. of the SB, except that scrapping of corroded parts is not required. Replace any part that is corroded with an airworthy part before further flight. (e) An alternative method of compliance or adjustment of the compliance time that provides an acceptable level of safety may be used if approved by the Manager, Boston Aircraft Certification Office (ACO), FAA. Operators shall submit their requests through an FAA Principal Maintenance Inspector, who may concur or comment and then send it to the Manager, Boston ACO. Note 2: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Boston ACO. (f) Special flight permits may be issued in accordance with §§ 21.197 and 21.199 of the Federal Aviation Regulations (14 CFR 21.197 and 21.199) to operate the helicopter to a location where the requirements of this AD can be accomplished. (g) The inspections shall be done in accordance with Section 2., Accomplishment Instructions, in BF Goodrich Service Bulletin No. 76A-32-03, Revision 1, dated September 15, 2000. This incorporation by reference was approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies may be obtained from BF Goodrich Landing Gear Division, Attn.: Kenneth R. Madej, 8000 Marble Ave., Cleveland, OH 44105, telephone (216) 429-4461, fax (216) 429-4357. 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 Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC. (h) This amendment becomes effective on February 2, 2001. Issued in Fort Worth, Texas, on January 5, 2001. Henry A. Armstrong, Manager, Rotorcraft Directorate, Aircraft Certification Service. [FR Doc. 01-1121 Filed 1-17-01; 8:45 am] BILLING CODE 4910-13-U