97-26-03: Main Rotor Mast Flange

97-26-03 EUROCOPTER DEUTSCHLAND: Amendment 39-10246. Docket No. 97-SW-45- AD. Applicability: Model MBB-BK 117 A-1, A-3, A-4, B-1, B-2, and C-1 helicopters, certificated in any category. NOTE 1: This AD applies to each helicopter 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 helicopters that have been modified, altered, or repaired so that the performance of the requirements of this AD is affected, the owner/operator must use the authority provided in paragraph (c) to request approval from the FAA. This approval may address either no action, if the current configuration eliminates the unsafe condition, or different actions necessary to address the unsafe condition described in this AD. Such a request should include an assessment of the effect of the changed configuration on the unsafe condition addressed by this AD. In no case does the presence of any modification, alteration, or repair remove any helicopter from the applicability of this AD. Compliance: Required as indicated, unless accomplished previously. To detects cracks in the main rotor mast flange (flange), which, if not detected, could result in failure of the flange and subsequent loss of control of the helicopter, accomplish the following: (a) Before further flight, and thereafter at intervals not to exceed 100 hours time-in- service, visually inspect the flange in the ribbed area for cracks using a 5-power or higher magnifying glass in accordance with paragraphs 2.A.1. and 2.A.2. of the Accomplishment Instructions in Eurocopter Deutschland GmbH Alert Service Bulletin MBB-BK 117 No. ASB- MBB-BK 117-10-114, dated August 27, 1997. (b) If a crack is found as a result of the inspections specified in paragraph (a) of this AD, remove the cracked main rotor mast and replace it with an airworthy main rotor mast. (c) 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 Standards Staff, 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 Standards Staff. NOTE 2: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Rotorcraft Standards Staff. (d) Special flight permits will not be issued. (e) The inspection shall be done in accordance with Eurocopter Deutschland GmbH Alert Service Bulletin MBB-BK 117 No. ASB-MBB-BK 117-10-114, dated August 27, 1997. 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 American Eurocopter Corporation, 2701 Forum Drive, Grand Prairie, Texas 75053-4005, telephone (972) 641-3460, fax (972) 641-3527. Copies may be inspected at the FAA, Office of Regional Counsel, Southwest Region, 2601 Meacham Blvd., Room 663, Fort Worth, Texas 76137; 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 Luftahrt-Bundesamt (Germany) AD 97-276, effective September 25, 1997. (f) This amendment becomes effective on December 31, 1997.