AD 2000-13-08

This amendment supersedes an existing airworthiness directive (AD) that applies to Eurocopter Deutschland GmbH (ECD) Model EC 135 helicopters. That AD requires conducting a tail rotor drive shaft vibration survey (survey), installing a Fenestron Shaft Retrofit Kit, inspecting each tail rotor drive shaft bearing (bearing) attaching lock plate for bent-open tabs and broken or missing slippage marks, and visually inspecting each bearing support for cracks. This AD requires conducting the survey and installing the Fenestron Shaft Retrofit Kit. This AD also requires installing double bearing supports and struts, revising the required compliance time for the repetitive inspections of the bearing attach hardware and supports, and removing the requirement to contact the FAA if a lock plate tab is bent open or if slippage marks are broken or missing. This amendment is prompted by continued reports of misaligned or cracked bearing supports and loose bearing attachment bolts. The actions specified by this AD are intended to prevent loss of drive to the tail rotor and subsequent loss of control of the helicopter.

Final rule

2000-13-08 EUROCOPTER DEUTSCHLAND GmbH: Amendment 39-11807. Docket No. 98-SW-74- AD. Supersedes AD 98-15-25, Amendment 39-10866, Docket No. 98-SW-35-AD. \n\tApplicability: Model EC 135 helicopters, certificated in any category. \n\n\tNOTE 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. \n\n\tCompliance: Required as indicated, unless accomplished previously. \n\n\tTo prevent loss of drive to the tail rotor and subsequent loss of control of the helicopter, accomplish the following: \n\n\t(a)\tBefore further flight, conduct a tail rotor drive shaft vibration survey and install a Fenestron Shaft Retrofit Kit L535M3002 882 in accordance with Eurocopter Deutschland GmbH Alert Service Bulletin (ASB) EC 135-53A-005, Revision 3, dated September 2, 1998. \n\n\t(b)\tBefore further flight, install double bearing supports for the tail rotor driveshaft and tail boom struts in accordance with ASB EC 135-53A-004, dated August 14, 1998. \n\n\tNOTE 2: ASB EC 135-53A-002, Revision 2, dated September 2, 1998, pertains to the subject of this AD. \n\n\t(c)\tBefore further flight and thereafter at intervals not to exceed 50 hours time-in-service, perform the following: \n\n\t\t(1)\tClean each tail rotor drive shaft bearing support. Using a 6-power or higher magnifying glass and a bright light, visually inspectthe attach lugs of the bearing supports B and C (shown in Figure 1) for cracks, particularly in the area extending from the bend radius to the attaching screws and rivets connecting the bearing supports to the tail boom. Before further flight, replace each cracked bearing support with an airworthy bearing support. \n\n\t\t(2)\tInspect each bearing attach hardware lock plate for bent-open tabs and slippage marks for attach hardware looseness or rotation. Before further flight, replace any loose bearing attach hardware (including lock plates found bent or open due to bolt rotation) with airworthy hardware. \n\n\t(d)\tAn 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. \n\n\tNOTE3: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Regulations Group. \n\n\t(e)\tSpecial 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. \n\n\t(f)\tThe modifications shall be done in accordance with Eurocopter Deutschland GmbH Alert Service Bulletin EC 135-53A-005, Revision 3, dated September 2, 1998, and Eurocopter Deutschland GmbH Alert Service Bulletin EC 135-53A-004, dated August 14, 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 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 Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC. \n\n\t(g)\tThis amendment becomes effective on August 9, 2000. \n\n\tNOTE 4: The subject of this AD is addressed in Luftfahrt-Bundesamt (Federal Republic of Germany) AD's 1998-033/7 and 1998-389, both dated September 14, 1998.

A proposal to amend part 39 of the Federal Aviation Regulations (14 CFR part 39) by superseding AD 98-15-25, Amendment 39-10866 (63 FR 59206, November 3, 1998), that applies to ECD Model EC 135 helicopters, was published in the Federal Register on April 6, 2000 (65 FR 18010). That action proposed to require the following:\n\n\to Conducting a vibration survey and installing the Fenestron Shaft Retrofit Kit L535M3002 882; \n\n\to Installing double bearing supports and struts;\n\n\to Inspecting and, if necessary, replacing bearing attach hardware; and\n\n\to Increasing the repetitive inspection interval for the bearing supports and attach hardware to 50 hours time-in-service (TIS). \n\n\tInterested persons have been afforded an opportunity to participate in the making of this amendment. No comments were received on the proposal or the FAA's determination of the cost to the public. The FAA has determined that air safety and the public interest require the adoption of the rule as proposed. \n\n\tThe FAA estimates that 16 helicopters of U.S. registry will be affected by this AD. The 50-hour inspection will take approximately 2 work hours to complete. The average labor rate is $60 per work hour. ECD has stated in its ASB's that the baseline vibration measurements and initial installation of all new parts will be provided at no charge to the owner/operator. Assuming the helicopters are operated 900 hours TIS per year, the total cost impact of this AD on U.S. operators is estimated to be $34,560. \n\n\tThe regulations adopted herein will not have a substantial direct effect on the States, on the relationship between the national Government and the States, or on the distribution of power and responsibilities among the various levels of government. Therefore, it is determined that this final rule does not have federalism implications under Executive Order 13132. \n\n\tFor the reasons discussed above, I certify that this action (1) is not a"significant regulatory action" under Executive Order 12866; (2) is not a "significant rule" under DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979); and (3) will not have a significant economic impact, positive or negative, on a substantial number of small entities under the criteria of the Regulatory Flexibility Act. A final evaluation has been prepared for this action and it is contained in the Rules Docket. A copy of it may be obtained from the Rules Docket at the location provided under the caption "ADDRESSES." \n\nList of Subjects in 14 CFR Part 39 \nAir transportation, Aircraft, Aviation safety, Incorporation by reference, Safety. \n\nAdoption of the Amendment \nAccordingly, pursuant to the authority delegated to me by the Administrator, the Federal Aviation Administration amends part 39 of the Federal Aviation Regulations (14 CFR part 39) as follows: \n\nPART 39 - AIRWORTHINESS DIRECTIVES \n1. The authority citation for part 39 continues to read as follows: \n\tAuthority: 49 U.S.C. 106(g), 40113, 44701. \n\n§ 39.13 (Amended) \n2. Section 39.13 is amended by removing Amendment 39-10866, and by adding a new airworthiness directive (AD), Amendment 39-11807, to read as follows: