99-13-10: Hydraulic Relief Valve

99-13-10 BELL HELICOPTER TEXTRON CANADA: Amendment 39-11203. Docket No. 98-SW-62-AD. Applicability: Model 206L-4 helicopters, serial numbers 52001 through 52208, 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 (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 within 300 hours time-in-service, unless accomplished previously. To prevent intermittent hydraulic pressure to the flight controls and subsequent loss of control of the helicopter, accomplish the following: (a) Remove hydraulic relief valve, part number (P/N) 206-076-036-101, and replace it with an improved hydraulic relief valve, P/N 206-076-036-105, in accordance with the Accomplishment Instructions in Bell Helicopter Textron Alert Service Bulletin No. 206L-98-111, dated July 24, 1998. (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, Rotorcraft Certification Office, Rotorcraft Directorate, FAA. Operators shall submit their requests through an FAA Principal Maintenance Inspector, who may concur or comment and then send it to the Manager, Rotorcraft Certification Office. NOTE 2: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Rotorcraft Certification Office. (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 helicopter to a location where the requirements of this AD can be accomplished. (d) Replacement of the valve shall be done in accordance with the Accomplishment Instructions in Bell Helicopter Textron Alert Service Bulletin No. 206L-98-111, dated July 24, 1998. 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 Bell Helicopter Textron Canada, 12,800 Rue de l'Avenir, Mirabel, Quebec JON1LO, telephone (800) 463-3036, fax (514) 433-0272. 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. NOTE 3: The subject of this AD is addressed in Transport Canada (Canada) AD CF-98-34, dated September 10, 1998. (e) This amendment becomes effective on August 2, 1999.