AD 99-20-11 Airworthiness Directives; Burkhart Grob Luft-Und Raumfahrt GmbH & CO KG Models G103 TWIN II and G103A TWIN II ACRO Sailplanes

The following sailplane models and serial numbers, certificated in any category: ------------------------------------------------------------------------ Model Serial Numbers ------------------------------------------------------------------------ G103 TWIN II.............................. 3501 through 3729. G103A TWIN II ACRO........................ 3501K through 3729K. ------------------------------------------------------------------------ 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 (g) 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 the inability to use the rear control stick because of a cracked knurled nut, which could result in loss of control of the sailplane during flight instruction operations, accomplish the following: (a) Prior to each flight, check the fastening (knurled) nut at the rear control stick for cracks. (b) At whichever of the following times that occurs first, replace the knurled nut at the rear control stick with a stainless steel nut, part number 103-4205.03/2. This part is included with Grob Service Bulletin 315-61/2, dated June 28, 1999: (1) Prior to further flight if any cracked knurled nut is found during any preflight check required by paragraph (a) of this AD; or (2) Within the next 4 calendar months after the effective date of this AD if no cracks are found during any preflight check required by paragraph (a) of this AD. (c) Replacing the knurled nut at the rear control stick with a stainless steel nut, part number 103-4205.03/2, is considered terminating action for the preflight checks required by paragraph (a) of this AD. (d) The preflight checks required by paragraph (a) of this AD may be accomplished by the owner/operator holding at least a private pilot certificate as authorized by section 43.7 of the Federal Aviation Regulations (14 CFR 43.7), and must be entered into the aircraft records showing compliance with this AD in accordance with section 43.9 of the Federal Aviation Regulations (14 CFR 43.9). (e) As of the effective date of this AD, no person may install, on any affected sailplane, a knurled nut at the rear control stick that is not part number 103-4205.03/2. (f) 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. (g) 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, FAA, 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 2: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Small Airplane Directorate. (h) Questions or technical information related to Grob-Werke GmbH & Co., Aerospace Division, P.O. Box 12 57, D-87712 Mindelhein, Federal Republic of Germany; telephone: ++ 49 8268 998-0; facsimile: ++ 49 8268 988-190. This service information may be examined at the FAA, Central Region, Office of the Regional Counsel, Room 1558, 601 E. 12th Street, Kansas City, Missouri 64106. Note 3: The subject of this AD is addressed in German AD 1999- 216/2, dated July 15, 1999, and in Grob Service Bulletin 315-61/2, dated June 28, 1999. (i) This amendment becomes effective on October 21, 1999. Issued in Kansas City, Missouri, on September 20, 1999. Michael Gallagher, Manager, Small Airplane Directorate, Aircraft Certification Service. [FR Doc. 99-25220 Filed 9-28-99; 8:45 am] BILLING CODE 4910-13-U