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 issues the following Airworthiness Directive (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 an 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. Univair Aircraft (Stinson) 108 Series Aeroplanes AD/STINSON 108/2 Stabilizer Leading Edge 17/2018 Attachment - Inspection Applicability: Univair Aircraft Corporation Stinson 108 series aircraft, serial numbers 1 through 3500. Requirement: 1. Inspect stabilizer leading edge attachment in accordance with the instructions in Stinson Service Bulletin 254 dated 5 September 1947, as in force at the commencement of this AD. 2. If during the Requirement 1 inspection, fatigue cracks of the stabilizer leading edge attachment are found, reinforcements to the stabilizer fitting must be added in accordance with the instructions in Stinson Service Bulletin 254 dated 5 September 1947, as in force at the commencement of this AD. Note: FAA AD 47-50-12 refers. Compliance: 1. Within 30 days after the commencement date of this AD, unless previously accomplished, and thereafter at intervals not to exceed 100 hours' time in service. 2. Before further flight. This AD commences on 31 August 2018. Background: A review of the Australian Aircraft Register found that this aircraft type has been registered in Australia since 1987. There are currently 12 aircraft of this type on the register with the majority having been registered in 1994/95. This AD is issued detect and correct fatigue cracking of the stabilizer leading edge attachment. Pieter van Dijk Delegate of the Civil Aviation Safety Authority 21 August 2018