99-27-04: Low Torque Switches

99-27-04 Rolls-Royce Limited: Amendment 39-11485. Docket 99-NE-30-AD. Issued December 21, 1999. Applicability: Rolls-Royce Limited (R-R) Dart 506, 510, 511, 514, 525, 526, 529, 530, 531, 532, 535, 542, and 552 series turboprop engines, installed on but not limited to Gulfstream Aerospace Corp. G-159, British Aerospace HS 748, Fokker Aircraft F.27, Mitsubishi Heavy Industries YS-11, General Dynamics (Convair) 640 and 600 series, and Vickers Armstrongs (Aircraft Limited) Viscount. 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 failure of a propeller to auto-feather following an engine power loss, resulting in possible loss of control of the airplane due to high asymmetric drag, accomplish the following: Inspection (a) Within 3 months after the effective date of this AD, accomplish the following in accordance with the Action section of R-R Service Bulletin (SB) No. Da61-13, dated December 1996: (1) Remove the switch cover, visually inspect the interior of the switch and replace the switch cover, all in accordance with the accomplishment instructions of the SB. (2) If a Klixon low torque switch, part number (P/N) 6PS-25-1, is installed, prior to further flight remove the Klixon low torque switch from service and replace with an approved low torque switch. 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. Ferry Flights (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 airplane to a location where the requirements of this AD can be accomplished. Incorporation by Reference (d) The actions required by this AD shall be done in accordancewith R-R SB No. Da61-13, dated December 1996. 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 Limited, Attn: Dart Engine Service Manager, East Kilbride, Glasgow G74 4PY, Scotland; telephone: +44 1355-220-200, fax: +44 1141-778-432. 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. (e) This amendment becomes effective on February 28, 2000.