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/11 Lower Cabin Door Jamb - Inspection 6/75 Applicability: Model 24 with S/Nos. 24-272, 24-295 to 319 except 24-303, 24-304 and 24-305. Model 25 with S/Nos. 25-134, 25-168 to 25-195 with 24 inch door installed. Document: Gates Learjet SB 24/25-260. Compliance: Within 100 hours time in service after 31 July 1975.