2008-26-12: Control bridge

2008-26-12 Aircraft Industries a.s. (Type Certificate G60EU previously held by LETECK Z VODY a.s. and LET Aeronautical Works): Amendment 39-15778; Docket No. FAA-2008-1138; Directorate Identifier 2008-CE-059-AD. Effective Date (a) This airworthiness directive (AD) becomes effective January 28, 2009. Affected ADs (b) None. Applicability (c) This AD applies to Model L 23 Super Blanik sailplanes, all serial numbers, certificated in any category. Subject (d) Air Transport Association of America (ATA) Code 27: Flight Controls. Reason (e) The mandatory continuing airworthiness information (MCAI) states: This Airworthiness Directive (AD) is prompted by the discovery on L 23 SUPER-BLANIK sailplanes of cracks in zones where the front and aft control levers attach the connecting rod designated as "control bridge'' on the relevant Illustrated Parts Catalogues (IPC). If left uncorrected cracks could propagate and lead to the breakage of the connecting rod with subsequent loss of control of the sailplane. For the reasons described above, this AD requires an inspection for cracks of the control bridge and its replacement, as necessary. In addition, this AD requires an update of the aircraft Maintenance Manual (MM) to incorporate repetitive inspections of the control bridge. Actions and Compliance (f) Unless already done, do the following actions: (1) Within the next 3 months after January 28, 2009 (the effective date of this AD) and repetitively thereafter at intervals not to exceed 12 months, visually inspect the control bridge in areas of juncture with the two control sticks for cracks. Do the inspection following paragraph A of LET Aircraft Industries, a.s. Mandatory Bulletin MB No. L23/050a, Revision No. 2, dated September 12, 2007, except use a 10X magnifier and do a dye penetrant inspection following the procedures in chapter 5, section 5, of FAA Advisory Circular AC 43.13-1B CHG 1, dated September 27, 2001.(2) If cracks are found in the control bridge bedding during any inspection required in paragraph (f)(1) of this AD, before further flight, replace the defective control bridge bedding, Dwg. No. A740 371N, in the control bridge assembly, Dwg. No. A740 370N, following LET Aircraft Industries, a.s. Mandatory Bulletin MB No. L23/050a, Revision No. 2, dated September 12, 2007; and Appendix No. 1, "Replacement of Bearings 608 CSN 024630 at Control Bridge Dwg. No. A740 370N in a Bedding Dwg. No. A740 371N,'' to LET Aircraft Industries, a.s. Mandatory Bulletin MB No. L23/050a, Revision No. 2, dated September 12, 2007. (3) Doing the replacement required in paragraph (f)(2) of this AD terminates the 12-month repetitive inspection required in paragraph (f)(1) of this AD. After the replacement required in paragraph (f)(2) of this AD, perform subsequent inspections on the new control bridge assembly according to LET Aircraft Industries, a.s. Documentation Bulletin No.: L23/020 d, dated August 6, 2007. FAA AD Differences Note: This AD differs from the MCAI and/or service information as follows: (1) The service information requires a visual inspection with a 6X magnifier. We are requiring a dye penetrant inspection and a 10X magnifier to detect cracks that could go undetected using only a 6X magnifier. (2) The MCAI requires updating the maintenance manuals to add repetitive inspections of the control bridge. Since the maintenance manual is only one way of establishing a maintenance program, the only way we can mandate these repetitive inspections is through an AD action. We have made these repetitive inspections part of this AD. Other FAA AD Provisions (g) The following provisions also apply to this AD: (1) Alternative Methods of Compliance (AMOCs): The Manager, Standards Office, FAA, has the authority to approve AMOCs for this AD, if requested using the procedures found in 14 CFR 39.19. Send information to ATTN: Greg Davison, Aerospace Engineer,FAA, Small Airplane Directorate, 901 Locust, Room 301, Kansas City, Missouri 64106; telephone: (816) 329-4130; fax: (816) 329-4090. Before using any approved AMOC on any sailplane to which the AMOC applies, notify your appropriate principal inspector (PI) in the FAA Flight Standards District Office (FSDO), or lacking a PI, your local FSDO. (2) Airworthy Product: For any requirement in this AD to obtain corrective actions from a manufacturer or other source, use these actions if they are FAA-approved. Corrective actions are considered FAA-approved if they are approved by the State of Design Authority (or their delegated agent). You are required to assure the product is airworthy before it is returned to service. (3) Reporting Requirements: For any reporting requirement in this AD, under the provisions of the Paperwork Reduction Act (44 U.S.C. 3501 et seq.), the Office of Management and Budget (OMB) has approved the information collection requirements and has assigned OMB Control Number 2120-0056. Related Information (h) Refer to MCAI European Aviation Safety Agency (EASA) AD No. 2007-0261, dated October 2, 2007; LET Aircraft Industries, a.s. Mandatory Bulletin MB No. L23/050a, Revision No. 2, dated September 12, 2007; Appendix No. 1, "Replacement of Bearings 608 CSN 024630 at Control Bridge Dwg. No. A740 370N in a Bedding Dwg. No. A740 371N,'' to LET Aircraft Industries, a.s. Mandatory Bulletin MB No. L23/050a, Revision No. 2, dated September 12, 2007; LET Aircraft Industries, a.s. Documentation Bulletin No.: L23/020 d, dated August 6, 2007; and FAA Advisory Circular AC 43.13-1B CHG 1, dated September 27, 2001, for related information. FAA Advisory Circular AC 43.13-1B CHG 1, dated September 27, 2001, can be found on the Internet at http://rgl.faa.gov/. Material Incorporated by Reference (i) You must use LET Aircraft Industries, a.s. Mandatory Bulletin MB No. L23/050a, Revision No. 2, dated September 12, 2007; Appendix No. 1, "Replacement of Bearings 608 CSN 024630 at Control Bridge Dwg. No. A740 370N in a Bedding Dwg. No. A740 371N,'' to LET Aircraft Industries, a.s. Mandatory Bulletin MB No. L23/050a, Revision No. 2, dated September 12, 2007; and LET Aircraft Industries, a.s. Documentation Bulletin No.: L23/020 d, dated August 6, 2007, to do the actions required by this AD, unless the AD specifies otherwise. (1) The Director of the Federal Register approved the incorporation by reference of this service information under 5 U.S.C. 552(a) and 1 CFR part 51. (2) For service information identified in this AD, contact Aircraft Industries, a.s. Na Z honech 1177, 686 04 Kunovice, Czech Republic; phone: +420-572816002; fax: +420-572816006; Internet: http://www.let.cz/. (3) You may review copies at the FAA, Central Region, Office of the Regional Counsel, 901 Locust, Room 506, Kansas City, Missouri 64106; or at the National Archives and Records Administration (NARA). For information on the availability of this material atNARA, call 202-741-6030, or go to: http://www.archives.gov/federal- register/cfr/ibr-locations.html.