AD 97-24-06 Airworthiness Directives; Glasflugel Models Standard Libelle and Standard Libelle 201 B Sailplanes

Models Standard Libelle and Standard Libelle 201 B Sailplanes (all serial numbers), certificated in any category. Note 1: This AD applies to each sailplane 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 sailplanes 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 (e) 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.

Required as indicated in the body of this AD, unless already accomplished. To prevent cracks in the aileron operating lever's actuating shaft welded seams, which, if not detected and corrected, could cause loss of control of the sailplane, accomplish the following: (a) Within the next 30 calendar days after the effective date of this AD, inspect for cracks in the paint of the aileron operating lever's actuating shaft welded seams using a magnifying glass (2x minimum) and a flashlight, and if there are cracks in the paint, then prior to further flight, remove the actuating shaft and perform a dye-penetrant inspection for cracks in accordance with Method 1 in the Accomplishment Instructions section and Figure 1 of the Appendix to this AD. (1) If cracks are seen in the actuating shaft, prior to further flight, either: (i) Repair any cracked welded seams, and modify the shaft in accordance with Method 2 of the Accomplishment Instructions and Figure 2 in the Appendix of this AD; or, (ii) Remove and replace the shaft with a new Glasflugel reinforced shaft in accordance [[Page 6631]] with Figure 1 and Method 3 in the Accomplishment Instructions in the Appendix of this AD. (2) If no cracks are found, within the next 8 calendar months after the inspection required by paragraph (a) of this AD, either: (i) Modify the aileron operating lever's shaft in accordance with Method 2 of the Accomplishment Instructions in the Appendix of this AD; or, (ii) Remove and replace the shaft with a new Glasflugel reinforced shaft in accordance with Method 3 in the Accomplishment Instructions and Figure 1 in the Appendix of this AD. Note 2: The FAA recommends that the shafts be finished with zinc-chromate primer and paint with a grayish-green shade. (b) After completing any action described in paragraph (a) or any sub-paragraph of (a) in this AD, prior to further flight, check and adjust the aileron deflection range in accordance with the ``Remarks'' paragraph in the Accomplishment Instructions in the Appendix of this AD. (c) Accomplishing all of the actions specified in the Accomplishment Instructions section of Glasfaser-Flugzeug Service GmbH Technical Note 201-33, dated March 4, 1996, incorporates the intent of this AD. No further action is required. (d) Special 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 sailplane to a location where the requirements of this AD can be accomplished. (e) An alternative method of compliance or adjustment of the compliance times that provides an equivalent level of safety may be approved by the Manager, Small Airplane Directorate, 1201 Walnut, suite 900, Kansas City, Missouri 64106. The request shall be forwarded through an appropriate FAA Maintenance Inspector, who may add comments and then send it to the Manager, Small Airplane Directorate. Note 3: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Small Airplane Directorate. (f) Information related to this AD may be examined at the FAA, Central Region, Office of the Regional Counsel, Room 1558, 601 E. 12th Street, Kansas City, Missouri. Appendix to AD 97-24-06--Aileron Actuating Shaft Accomplishment Instructions Method 1: Note: The term ``WIG-inert protective atmosphere welding system'' used within the Appendix text has the U.S. equivalent of Tungsten Inert Gas (TIG) welding system. Using a magnifying glass (2x minimum) and a flashlight, inspect the aileron actuating shaft in the fuselage (see Figure 1) near the welding seams for cracks in the paint. If there is any cracked paint on the actuating shaft, prior to further flight, remove the actuating shaft and inspect for cracks in the shaft and welding seams using a dye-penetrant method. If there are no cracks or any other damage, flying operation can continue until the accumulation of 8 calendar months after the initial inspection required by this AD, at which time Method 2 or Method 3 shall be accomplished. If cracks are found, prior to further flight, accomplish Method 2 or Method 3. Note: In Figure 2, the doubler has physical dimensions of: 90 mm x 12 mm x 1 mm, with the ends having a radius of 6 mm. Appendix to AD 97-24-06--Aileron Actuating Shaft Method 2: Remove all paint. Weld (grove welding) all cracks. Weld the joints with the WIG-inert protective atmosphere welding system (wolfram inert gas welding system) with welding material 1.7734.2. Weld the plates (position 7) to the actuating shaft according to Figure 2. Finish the actuating shaft with primer and paint (paint type RAL 7003). Reinstall the aileron actuating shaft. Note: Method 2 in the Appendix refers to welding material 1.7734.2. The FAA and the LBA were unable to determine the U.S. equivalent to this material. The recommended options would be to order the original part from the manufacturer, order the welding material from the manufacturer, or order welding material 1.7734.2 from Germany, Italy or France. Method 3: As an alternative to Method 2, replace the original actuating shaft with a new reinforced shaft according to Figure 1. Mass and balance: Not Affected. Appendix to AD 97-24-06--Aileron Actuating Shaft Remarks For rigging and derigging procedures, refer to the flight manual, page E12. After accomplishing repairs according to Method 2, or replacement of the actuating shaft according to Method 3, the aileron deflections must be checked. Plates, welding material, and spare parts as mentioned are available from the manufacturer. BILLING CODE 4910-13-P [[Page 6632]] [GRAPHIC] [TIFF OMITTED] TR10FE98.002 [[Page 6633]] [GRAPHIC] [TIFF OMITTED] TR10FE98.003 (g) This amendment (39-10213) becomes effective on March 13, 1998. Issued in Kansas City, Missouri, on February 2, 1998. Carolanne L. Cabrini, Acting Manager, Small Airplane Directorate, Aircraft Certification Service. [FR Doc. 98-3130 Filed 2-9-98; 8:45 am] BILLING CODE 4910-13-C