COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES Pilatus PC-12 Series Aeroplanes AD/PC-12/11 Flap System - Alternate Flap Capability Removal 13/98 DM Applicability: Model PC12 and PC12/45 aircraft with Manufacturer's Serial Numbers (MSN) 101 to 227 (incl) and 232. Requirement: 1. Remove the ALTERNATE FLAP switch from the centre console in the cockpit and replace with a blanking plate in accordance with Pilatus Service Bulletin No. 27-004 dated 15 September 1998. 2. Install a FLAP MAINT switch in accordance with Pilatus Service Bulletin No. 27- 004 dated 15 September 1998. 3. Insert appropriate Pilatus Temporary Revisions into Pilot's Operating Handbook and Aircraft Maintenance Manual in accordance with Pilatus Service Bulletin No. 27-004 dated 15 September 1998. Note: FOCA AD HB 98-352 dated 28 September 1998 refers. Compliance: Within 30 days of the effective date of this directive. This Airworthiness Directive becomes effective on 4 November 1998. Background: Investigations of accidents and operating techniques around the world have revealed that operating crews are misusing the Alternate Flaps system on the PC12 aircraft. FOCA has decided to remove the system from the centre console of the cockpit pending the issue of modifications to improve the reliability of the automatic PC12 flap system.