Airworthiness Directive · Amendment 39-14961 · Eurocopter Deutschland GmbH Model MBB-BK 117 C-2 Helicopters
Eurocopter Deutschland GmbH Model MBB-BK 117 C-2 Helicopters
Superseded. A later AD replaced this one: AD 2010-22-07. Comply with the one in force.
Model MBB-BK 117 C-2 helicopters, serial number (S/N) 9075 and higher, and those helicopters from S/N 9004 up to and including 9074, on which Service Bulletin MBB BK117 C-2-67-006 has been accomplished, with a tail rotor control lever B642M1009103, installed, certificated in any category.
Note 1: The referenced Eurocopter Alert Service bulletin MBB BK 117 C-2-67-006, dated July 25, 2006, pertains to the subject of this AD. That ASB states that it offers improvements with regard to a reduction of the operational pedal control forces and involves two modifications. One of the modifications involves installing an optimized tail rotor control lever assembly “consisting of modified weights and modified control lever pre-assys.” Installing the optimized tail rotor control lever assembly, in part, involved replacing the 2 control levers, part number (P/N) B642M1009102, with 2 control levers, P/N B642M1009103, and replacing the 4 weights, P/N B642M1011201, with 4 weights, P/N B642M1011202.
This document publishes in the Federal Register an amendment adopting Airworthiness Directive (AD) 2006-26-51, which was sent previously to all known U.S. owners and operators of Eurocopter Deutschland GmbH (ECD) Model MBB-BK 117 C-2 helicopters by individual letters. This AD requires, before further flight, marking the position of the tail rotor control lever dynamic weights (weights), removing the split pins and the weights, and visually inspecting and replacing, if necessary, the tail rotor control lever before further flight. This AD also requires, within 10 hours time-in-service (TIS), and thereafter at intervals not to exceed 25 hours TIS, repeating the visual inspection of the tail rotor control lever and replacing any unairworthy tail rotor control lever with an airworthy tail rotor control lever before further flight. Also required is reassembling the tail rotor control lever by following the appropriate maintenance instruction. This amendment is prompted by an in-flight incident in which the threaded portion of the tail rotor control lever containing a dynamic weight broke off leading to severe vibrations. The actions specified by this AD are intended to prevent separation of the weights in flight, severe vibration, and subsequent loss of control of the helicopter.
Required as indicated, unless accomplished previously.
To prevent separation of the tail rotor control lever dynamic weights (weights) in flight, severe vibration, and subsequent loss of control of the helicopter, accomplish the following:
(a) Before further flight, mark the position of the weights, remove the split pins, remove the weights, and visually inspect the tail rotor control lever in the area around the split pin bore for score marks, notching, scratching, or a crack. Conduct the inspection by following the Accomplishment Instructions, paragraph 3A(1) and Figure 1 of Eurocopter Alert Service Bulletin No. MBB BK117 C-2-64A-002, dated December 21, 2006 (ASB).
(1) If you find score marks, notching, or scratches, that exceed the maintenance manual limits, or find a crack, replace the tail rotor control lever with an airworthy tail rotor control lever before further flight.
(2) If you do not find score marks, notching, scratches, or a crack, within 10 hours time-in-service (TIS), and thereafter at intervals not to exceed 25 hours TIS, repeat the visual inspection of the tail rotor control lever as described in paragraph (a) of this AD.
(3) After any repetitive inspection, if you find score marks, notching, or scratches, that exceed the maintenance manual limits or find a crack, replace the tail rotor control lever with an airworthy tail rotor control lever before further flight.
(4) Reassemble the tail rotor control lever by following the appropriate maintenance instructions and the Accomplishment Instructions, paragraph 3A(4) and Figure 1 of the ASB.
(b) To request an alternative method of compliance or a different compliance time for this AD, follow the procedures in 14 CFR 39.19. Contact the Manager, Safety Management Group, FAA, ATTN: Charles Harrison, Aviation Safety Engineer, FAA, Rotorcraft Directorate, Fort Worth, Texas 76193-0110, telephone (817) 222-5128, fax (817) 222-5961, for information about previously approved alternative methods of compliance.
(c) Special flight permits will not be issued.
(d) The inspections and reassembly shall be done in accordance with the specified portions of Eurocopter Alert Service Bulletin No. MBB BK117 C-2-64A-002, dated December 21, 2006. The Director of the Federal Register approved this incorporation by reference 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 the Regional Counsel, Southwest Region, 2601 Meacham Blvd., Room 663, Fort Worth, Texas or at the National Archives and Records Administration (NARA). For information on the availability of this material at NARA, call 202-741-6030, or go to: http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html.
(e) This amendment becomes effective on April 9, 2007, to all persons except those persons to whom it was made immediately effective by Emergency AD 2006-26-51, issued December 22, 2006, which contained the requirements of this amendment.
Note 2: The subject of this AD is addressed in Luftfahrt-Bundesamt (Federal Republic of Germany) AD D-2006-428, dated December 22, 2006.
The aircraft, engines and makers this AD names, by the model designations in its text. A model listed here may still be outside the AD's serial ranges.
