2001-04-12: Main Gearbox Coupling Tube Assembly

2001-04-12 EUROCOPTER FRANCE: Amendment 39-12131. Docket No. 2000-SW-31-AD. Applicability: Model EC120B helicopters, with engine to main gearbox (MGB) coupling tube assembly (tube), part number C631A1101101, 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 (d) 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 a tube failure, loss of engine drive, and a subsequent forced landing, accomplish the following: (a) Within 5 hours time-in-service (TIS) and thereafter at intervals not to exceed 5 hours TIS, visually check each affected tube for a crack as follows: (1) Open the left and right cowlings. (2) Check inside the MGB in the area of the tube cylindrical casing on either side of the fitting that attaches the tube to the MGB. (b) Before further flight, replace any cracked tube with an airworthy tube. Note 2: Eurocopter France Service Bulletin 05-003, dated July 20, 2000, pertains to the subject of this AD. (c) An owner/operator (pilot) holding at least a private pilot certificate may perform the visual check required by paragraph (a) and must enter compliance with paragraph (a) of this AD into the aircraft maintenance records in accordance with 14 CFR 43.11 and 91.417(a)(2)(v). (d) 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, Regulations Group, 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, Regulations Group. Note 3: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Regulations Group. (e) Special flight permits will not be issued. (f) This amendment becomes effective on March 20, 2001. Note 4: The subject of this AD is addressed in Direction General De L'Aviation Civile (France), AD 2000-176-004(A) R1, dated August 23, 2000.