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/AT 600/1 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. Airtractor 600 Series Aeroplanes AD/AT 600/1 Amdt 1 Airframe Life Limits 25/2010 Applicability: All Models. Requirement: Retire from service the airframe components listed in the Retirement Schedule below. RETIREMENT SCHEDULE Component Part No. Retirement Life (Flight Hours) L/H Lower Spar Cap in Wing 20603-1 6500 R/H Lower Spar Cap in Wing 20603-2 6500 Wing Attach Block on Lower Cap 20602-1 6500 Wing Attach Block on Lower Cap 20602-2 6500 Plate Assy. - Fin Front Spar Attach 30511-1 As per the Airworthiness Limitations Section approved by the FAA in the Owners Manual Spar Assy. - Fin Rear 30315-1 As per the Airworthiness Limitations Section approved by the FAA in the Owners Manual Spring - Main Landing Gear Leg (including the forward and aft main gear clamp block bolts and the inboard main gear large bolt). 40086-4 3000 hours or 8000 landings, whichever occurs first Spring - Tail Landing Gear Leg 40092-4 3000 hours or 8000 landings, whichever occurs first Where the total number of landings during a period of service has not been recorded, three landings per one hour time in service must be assumed. Compliance: Retire prior to exceeding the applicable time in service listed in the Retirement Schedule. Note: The Type Certificate Data Sheet states that the lives are listed in the Maintenance Manual; however they are in fact listed in the Owners Manual. This Airworthiness Directive becomes effective on 21 December 2010. Background: The initial issue of this Directive was to formally promulgate the airframe components life limitations determined by the manufacturer. This amendment revises the retirement lives for two components (Plate Assy - Fin Front Spar Attach and Spar Assy - Fin rear) and corrects a part number. Mike Higgins Delegate of the Civil Aviation Safety Authority 6 December 2010