AD 2004-22-11 Airworthiness Directives; Eurocopter Deutschland GmbH Model EC135 P1, P2, T1, and T2 Helicopters

Models named: EC135 P1, P2, T1, T2. Read the applicability below — it usually turns on serial or part numbers too.

Model EC135 P1, P2, T1, and T2 helicopters, with main rotor drive aluminum torque strut assembly (strut), part number (P/N) L633M1001 103 or L633M1001 105, installed, certificated in any category.

Required as indicated, unless accomplished previously. To prevent failure of the strut and subsequent loss of control of the helicopter, do the following: (a) Before further flight, insert a copy of this AD or insert a statement into the Emergency Procedures Section of the Rotorcraft Flight Manual (RFM) to inform the pilot to reduce power and land as soon as practicable if a thump-like sound followed by an unusual vibration occurs during flight. (b) Before the first flight of each day, using a light and mirror, inspect each aluminum strut for a crack or a break by following the Accomplishment Instructions, paragraph 3.B. of Eurocopter Alert Service Bulletin EC135-63A-002, Revision 4, dated July 7, 2003 (ASB). Replace any cracked or broken strut with a new titanium strut, P/N L633M1001 104, before further flight. (c) Within the next 100 hours time-in-service (TIS), for each aluminum strut with 400 or more hours TIS, replace each aluminum strut with a titanium strut, P/N L633M1001 104. (d) This AD revises the Airworthiness Limitations section of the maintenance manual by reducing the retirement life of each aluminum strut, P/N L633M1001 103 and L633M1001 105, to 500 total hours TIS or retiring them no later than December 31, 2004, whichever comes first. (e) The aluminum struts must be replaced with titanium struts in pairs and at the same time. Installing one aluminum strut and one titanium strut is not authorized. After installing titanium struts, recalculate the weight and balance using 0.356kg as the weight and 1498.76kgmm as the moment for both titanium struts. Note 1: The once-only transferring and remarking of certain aluminum struts provided in the superseded AD are no longer authorized. (f) Replacing aluminum struts, P/N L633M1001 103 and L633M1001 105, with titanium struts, P/N L633M1001 104, constitutes terminating action for the requirements of this AD. Titanium struts have no life limit. (g) To request a different method of compliance or a different compliance time for this AD, follow the procedures in 14 CFR 39.19. Contact the Safety Management Group for information about previously approved alternative methods of compliance. (h) The inspections shall be done in accordance with Eurocopter Alert Service Bulletin EC135-63A-002, Revision 4, dated July 7, 2003. The Director of the Federal Register approved the 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. (i) This amendment becomes effective on December 7, 2004. Note 2: The subject of this AD is addressed in Luftfahrt-Bundesamt (Federal Republic of Germany) AD 2001-107/3, dated August 21, 2003. Issued in Fort Worth, Texas, on October 22, 2004. David A. Downey, Manager, Rotorcraft Directorate, Aircraft Certification Service. [FR Doc. 04-24226 Filed 11-1-04; 8:45 am] BILLING CODE 4910-13-P