AIRWORTHINESS DIRECTIVE On the effective date specified below, and for the reasons set out in the background section, the CASA delegate whose signature appears below revokes Airworthiness Directive (AD) AD/G164/14 and issues the following AD under subregulation 39.001(1) of CASR 1998. The AD requires that the action set out in the requirement section (being action that the delegate considers necessary to correct the unsafe condition) be taken in relation to the aircraft or aeronautical product mentioned in the applicability section: (a) in the circumstances mentioned in the requirement section; and (b) in accordance with the instructions set out in the requirement section; and (c) at the time mentioned in the compliance section. Schweizer (Grumman) G-164 (Ag-Cat) Series Aeroplanes AD/G164/14 Amdt 1 Elevator Control Horn Attach 10/2009 Bolts - Inspection and Replacement Applicability: All model G-164A and G-164B aircraft not modified to Gulfstream American Service Note No. 23. Requirement: 1. Inspect the bolts attaching the Elevator Control Horn P/No. A1841-3 to the left and right side elevators P/No's A1201-5A and A1201-4A respectively for looseness, wear and corrosion, and a standard torque rating of 50-70 in. lbs. Replace worn or corroded bolts. Note 1: Refer to revision to Grumman American Service Bulletin (SB) No. 51 for correct part numbers and alternative bolts. 2. Replace bolts referenced in Requirement 1. Note 2: FAA AD 73-19-10 refers. Compliance: 1. At intervals not exceeding 100 hours time in service or 60 days from time of compliance with previous issue if this Directive, whichever occurs first. 2. At intervals not exceeding 1000 hours time in service or one year from time of compliance with previous issue if this Directive, whichever occurs first. The repetitive inspection internals required by Requirement 1 may be discontinued upon installation of the modification kit to modify the elevator horn assembly referenced in Grumman American Service Note No. 23. This Amendment becomes effective on 24 September 2009. Background: This amendment better reflects the requirements of FAA AD 73-19-10, corrects a typographical error, includes a 60 day inspection interval required by the FAA and introduces terminating action for Requirement 1. David Villiers Delegate of the Civil Aviation Safety Authority 12 August 2009