2000-23-11: Disk Drive Arm

2000-23-11 Rolls-Royce: Amendment 39-11981. Docket 2000-NE-03-AD. Applicability: Rolls-Royce (RR) plc. Spey 555-15, -15H, -15N, and -15P turbofan engines. These engines are installed on but not limited to Fokker F.28 Mark series airplanes. Note 1: This airworthiness directive (AD) applies to each engine identified in the preceding applicability provision, regardless of whether it has been modified, altered, or repaired in the area subject to the requirements of this AD. For engines 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 (b) 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. Compliance: Required as indicated, unless accomplished previously. To prevent damage to the disk drive arm which could result in loss of stage 1 LP turbine-to- stage 2 LP turbine disk drive, a turbine overspeed condition and possible uncontained disk failure, and damage to the airplane, do the following: Rework Instructions (a) Within three years after the effective date of this AD, rework the low pressure (LP) turbine stage 2 nozzle guide vane (NGV) support ring seal assembly in accordance with paragraphs 2.A. through 2.C. of the Accomplishment Instructions of RR service bulletin (SB) No. Sp 72-1063, dated May 1999. Alternative Methods of Compliance (b) 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, Engine Certification Office (ECO). Operators shall submit their request through an appropriate FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, ECO. Note 2: Information concerning the existence of approved alternative methods of compliance with this airworthiness directive, if any, may be obtained from the ECO. Special Flight Permits (c) Special flight permits may be issued in accordance with sections 21.197 and 21.199 of the Federal Aviation Regulations (14 CFR 21.197 and 21.199) to operate the aircraft to a location where the requirements of this AD can be accomplished. (d) The rework shall be done in accordance with the following Rolls-Royce service bulletin: (SB) No. Sp 72-1063, dated May 1999.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 Rolls-Royce plc, PO Box 31, Derby, England, DE248BJ; telephone no. 011-44-1332-242-424; fax no. 011-44-1332-245-418. Copies may be inspected at the FAA, New England Region, Office of the Regional Counsel, 12 New England Executive Park, Burlington, MA; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC. Effective Date of This AD (e) This amendment becomes effective on December 20, 2000.