COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES Pitts S-1 and S-2 Series Aeroplanes AD/PITTS S-2/15 Amdt 1 Control Stick 12/96 Applicability: All Pitts aircraft models equipped with a control stick manufactured from a tube with a nominal wall thickness of 0.89 mm (0.035 inch). Requirement: Inspect the control stick in accordance with paragraph 5.A.(1) to 5.A.(6) of Aviat Service Bulletin (SB) No. 23, dated 29 March 1996. Where two control sticks are installed, both control sticks must be inspected. Note 1: FAA AD 96-10-12 refers. Note 2: Aviat SB No. 23 only refers to the model S-2A aeroplane. The inspection procedure of Aviat SB No. 23 is applicable to all models affected by this directive. Compliance: For aircraft that have not been inspected in accordance with the initial issue of this directive within 50 hours time in service before 7 November 1996, inspect before 10 hours time in service after 7 November 1996. For aircraft that have been inspected in accordance with the initial issue of this directive within 50 hours time in service before 7 November 1996, inspect within 50 hours time in service since last inspected. Re-inspect at intervals not to exceed 50 hours time in service. This amendment to the directive takes effect 7 November 1996. Background: The Authority received a report of the rear control stick failing in a Pitts S-2A. The failure occurred due to fatigue. Cracks had originated at the welds above the pitch pivot. The initial issue of this directive required inspection of all models and re- inspection for models S-2A and S-2S. This amendment modifies the applicability to require re-inspection of control sticks made from tube with a wall thickness of 0.89 mm (0.035 inch) only. Replacement of the control stick with one made from tube with increased wall thickness, available from the manufacturer, will relieve the inspection requirement. The initial issue of this Airworthiness Directive became effective on 31 January 1996.