COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES Gates Learjet 24 & 25 Series Aeroplanes AD/LEARJET/17 Amdt 1 Cabin Altitude Pressure Limiter - Installation 1/84 Applicability: All model 24 with S/Nos. 24-100 to 24-349; All model 25 with S/Nos. 25-003 to 25-226. Document: Learjet Airplane Mod. Kit AMK 78-5 or AMK 83-1 as applicable. Compliance: For Learjet Airplane Mod. Kit AMK 78-5 - within 600 hours time in service after 31 January 1979. For Learjet Airplane Mod Kit AMK 83-1 - within 300 hours time in service after 31 January 1984. Background: This Directive is raised in issue to include additional Models 24 with S/Nos 24-100 to 24-229 except S/No 24-218 and models 25 with S/Nos 25-003 to 25-066 except S/No 25-061 per Learjet Airplane Mod Kit AMK 83-1.