Airworthiness Directive · Amendment 39-16681 · Propellers/propulsors
BURKHART GROB LUFT-UND Model G 103 C Twin III SL Gliders
This AD applies to BURKHART GROB LUFT-UND G 103 C Twin III SL gliders, all serial numbers, certificated in any category.
We are adopting a new airworthiness directive (AD) for the products listed above. This AD results from mandatory continuing airworthiness information (MCAI) issued by an aviation authority of another country to identify and correct an unsafe condition on an aviation product. The MCAI describes the unsafe condition as:
Unless already done, within 30 days after the effective date of this AD, do the following actions:
(1) Update the glider documentation following Grob Aircraft Service Bulletin No. MSB-869-24/1, dated July 20, 2009, by inserting the following revised pages from Grob Aircraft AG:
(i) Into the Grob Aircraft AG G 103 C Twin III SL Pilot's Operating Handbook (POH) (dated December 1991): Pages 0.2A, 0.3, 0.4, and 4.9, Revision 6, dated July 20, 2009.
(ii) Into the Grob Aircraft AG G 103 C Twin III SL Maintenance Manual (dated December, 1991) or FAA-approved maintenance program: pages 0.1A, 0.2, 0.3, 4.2, and 6.6, Revision 10, dated December 15, 2006.
(2) Inspect for cracks at the bent area of the engaged tooth of the upper pulley wheel securing plate following the procedure to access the area found on page 6.12 of the Grob Aircraft AG G 103 C TWIN III SL Maintenance Manual, Date of Issue December, 1991, Revision 9, dated May 24, 2002, as specified in Grob Aircraft Service Letter SL 869-01, dated June 9, 2009.
(3) Verify that the propeller track (the play at the propeller tip) is within the allowable tolerances following the procedure on page 4.9 of the Grob Aircraft AG G 103 C TWIN III SL POH, Date of Issue December, 1991, Revision 6, dated July 20, 2009, as specified in Grob Aircraft Service Letter SL 869-01, dated June 9, 2009.
Note 1: The torque values and tolerances of the upper pulley wheel grooved nut have been standardized in the POH and maintenance manual.
(4) If the bent area of the engaged tooth of the upper pulley wheel securing plate has no crack found per the inspection of paragraph (f)(2) of this AD, but the propeller track value measured is not within the allowable tolerances per paragraph (f)(3) of this AD, before further flight, readjust the torque of the upper pulley wheel grooved nut using the updated aircraft technical documentation following the procedure on page 6.12 of the Grob Aircraft AG G 103 C TWIN III SL Maintenance Manual, Date of Issue December, 1991, Revision 9, dated May 24, 2002, as specified in Grob Aircraft Service Letter SL 869-01, dated June 9, 2009. Ensure accordingly that the propeller track is within the allowable tolerances following the procedure on page 4.9 of the Grob Aircraft AG G 103 C TWIN III SL POH, Date of Issue December, 1991, Revision 6, dated July 20, 2009, as specified in Grob Aircraft Service Letter SL 869-01, dated June 9, 2009. If the propeller track is out of the allowable tolerance, then contact GROB for further instructions.
(5) If any crack is found in the bent area of the engaged tooth of the upper pulley wheel securing plate per the inspection in paragraph (f)(2) of this AD, before further flight, do the following actions:
(i) Remove the upper pulley wheel grooved nut and then look at the securing plate to identify if other teeth are available to be bent to secure the grooved nut. Do not bend an already bent tooth. If all teeth of the securing plate are already bent, replace the securing plate with a serviceable one.
(ii) Screw back the upper pulley wheel grooved nut (and its securing plate) and tighten it, applying the torque following page 6.12 of the Grob Aircraft AG G 103 C TWIN III SL Maintenance Manual, Date of Issue December, 1991, Revision 9, dated May 24, 2002, as specified in Grob Aircraft Service Letter SL 869-01, dated June 9, 2009. Ensure accordingly that the propeller track is within the allowable tolerances following the procedure on page 4.9 of the Grob Aircraft AG G 103 C TWIN III SL POH, Date of Issue December, 1991, Revision 6, dated July 20, 2009, as specified in Grob Aircraft Service Letter SL 869-01, dated June 9, 2009. If the propeller track is out of the allowable tolerances, then contact GROB for further instructions.
Note 2: This AD differs from the MCAI and/or service information as follows: No differences.
The aircraft, engines and makers this AD names, by the model designations in its text. A model listed here may still be outside the AD's serial ranges.
