COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES Piaggio P166 Series Aeroplanes AD/P166/6 Fire Detection System - Modification NK Applicability: All P166 series in transport category. Requirement: Replace the existing nacelle heat detector system by an approved fire detector system complying with the requirement of ANO Section 101.1.3.1, Issue 2, paragraph 2.4. Compliance: Forthwith.