{"id":"F2006B06076","name":"AD/PC-12/13 Amdt 1 - Flap System","slug":"ad-pc-12-13-amdt-1-flap-system","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":114474,"registerId":"commonwealth-F2006B06076-current","compilationNumber":null,"startDate":"2026-04-03","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/PC-12/13 Amdt 1 - Flap System","content":"COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 \\- 105 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\n![](image.001.png)  \n![](image.002.png)  \nPilatus PC-12 Series Aeroplanes\n\nAIRWORTHINESS DIRECTIVE\n\n![](image.002.png)\n\n![](image.002.png)  \nFor the reasons set out in the background section, the CASA delegate whose signature appears below revokes Airworthiness Directive (AD) AD/PC-12/13 and issues the following AD under subregulation 39.1 (1) of CAR 1998. The AD requires that the action set out in the requirement section (being action that the delegate considers necessary to correct the 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.\n\nAD/PC-12/13\n\nAmdt 1\n\n  \nFlap System 1/2001 DM\n\nApplicability: All PC-12 and PC-12/45 aircraft.\n\nRequirement: 1\\. Inspect flap actuators to check axial end-play and backlash of each flap actuator in accordance with the Pilatus PC12 Maintenance Manual, Temporary Revision (TR) 27-13, dated 30 April 2000.\n\nIf the acceptance criteria specified in TR 27-13 cannot be met, replace defective actuators before further flight.\n\nCompliance with a later revision of the Pilatus PC12 Maintenance Manual approved by FOCA satisfies this Directive.\n\nNote 1: Switzerland FOCA AD’s HB 98-460 and HB 2000-443 refer.\n\n    2. Modify the flap system in accordance with Pilatus PC-12 Service Bulletin (SB) 27- 008, Revision 2, dated 13 September 2000.\n\nNote 2: Switzerland FOCA AD HB 2000-443 refers.\n\n    3. Amend the PC-12 Pilot’s Operating Handbook (POH) with POH/AFM Temporary Revision No. 15 - MODIFIED FLAP SYSTEM - dated 3 April 2000.\n\n    4. For aircraft incorporating SB 27-008 as of the effective date of this Directive, inspect the Flap Control and Warning Unit (FCWU) to determine its serial number and remove from service any FCWU, Part No. FCWU99-3 with serial number 100,000 or less in accordance with Pilatus PC-12 Service Bulletin (SB) 27-012, dated 13 September 2000. From the effective date of this Amendment, no such FCWU may be installed on any model Pilatus PC-12 aircraft.\n\nNote 3: Switzerland FOCA AD HB 2000-444 refers\n\nCOMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 \\- 105 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\nCompliance: 1. (a) Pre \\- SB 27-008 Configuration Flap System:\n\nWithin 65 landings following the last backlash inspection per the original issue of this Directive and, thereafter, at periods specified in Pilatus PC12 Maintenance Manual, Temporary Revision 04-05, dated 30 April 2000.\n\n(b) Post \\- SB 27-008 Configuration Flap System:\n\nConcurrent with the incorporation of SB 27-008 and thereafter at the intervals specified in the Pilatus PC12 Maintenance Manual, Chapter 05-10-20, Time Limited Inspection Requirements.\n\n    2. Unless previously accomplished either during production or by retrofit action, within the next 600 hours time in service after the effective date of this Directive but no later than 30 June 2001, whichever occurs first.\n\n    3. Concurrent with Requirement 2 of this Directive.\n\n    4. No later than 31 December 2000.\n\nThis Amendment becomes effective on 29 November 2000.\n\nBackground: Several flap actuators have been found with excessive backlash in the internal gear system. Excessive backlash may lead to rapid premature wear of the gear and in extreme cases to loss of actuator output. Internal failure of the worm gear could allow an actuator to turn freely. Detection of all potential failure modes by the flap control computer can not be assured.\n\nThis amendment mandates a modification that improves the flap system and extends the repetitive inspection interval for the flap actuator backlash check. The amendment also requires certain FCWU’s to be removed from service.\n\nThe original issue of this Airworthiness Directive became effective on 9 December 1998.\n\n![Signature of Eugene Paul Holzapfel, Delegate of the Civil Aviation Safety Authority.](image.003.png)  \n\nEugene Paul Holzapfel\n\nDelegate of the Civil Aviation Safety Authority 22 November 2000\n\n![](image.002.png)  \n\nThe above AD is notified in the Commonwealth of Australia Gazette on 29 November 2000.","sortOrder":0}],"analysis":{"flash_summary_failed":{"failed":true,"reason":"A positive credit balance is required for all requests, including BYOK, so fallback providers remain available. Add credits at https://vercel.com/d?to=%2F%5Bteam%5D%2F%7E%2Fai%3Fmodal%3Dtop-up to continue.","source":"analysis-cron"},"kimi_summary":{"content_quality":"ok","complexity_score":4,"scope_assessment":{"changed":false,"description":"This amendment remains focused on its original purpose—addressing unsafe flap actuator backlash in PC-12 aircraft. While it adds new requirements (the FCWU removal and the modification mandate), these are directly related to the original safety issue rather than scope creep. The amendment actually streamlines the original directive by extending inspection intervals for modified aircraft, suggesting refinement rather than expansion beyond the original safety intent."},"complexity_factors":["Multiple cross-references to external technical documents (Pilatus Maintenance Manual Temporary Revisions, Service Bulletins 27-008 and 27-012, Pilot's Operating Handbook revisions)","Conditional compliance deadlines that vary based on aircraft configuration (pre-modification vs post-modification status)","Dual-track compliance requirements (inspection intervals differ depending on whether SB 27-008 has been incorporated)","Specific part number and serial number restrictions (FCWU99-3 with serial ≤100,000)","References to foreign aviation authority directives (Swiss FOCA ADs HB 98-460, HB 2000-443, HB 2000-444)","Nested timing requirements (e.g., 'within 65 landings following the last backlash inspection' and 'whichever occurs first' clauses)"],"plain_english_summary":"This CASA Airworthiness Directive orders Pilatus PC-12/PC-12‑45 owners and operators to address dangerous wear in flap actuators that can cause gear failure and uncontrolled or inoperative flaps. It mandates inspections and replacement if out of tolerance, installation of a redesigned flap system per SB 27‑008 within the specified compliance window, updating the pilot handbook, and removal of certain FCWU units. The action prevents possible loss of control during landing."},"flash_summary":{"complexity_score":6,"scope_assessment":{"changed":true,"description":"The amendment expands the original AD by adding a mandated flap-system modification (SB 27-008), requiring removal of specific FCWU units by serial number, updating the POH, and revising recurring inspection intervals. The Background and Requirements 2–4 show these additions; Compliance clauses adjust when and how inspections and retrofits must occur. The practical effect shifts obligations from inspection-only to inspection-plus-retrofit and equipment removal, increasing retrofit and parts-replacement obligations for operators."},"complexity_factors":["Multiple distinct actions required: inspection, modification (SB 27-008), POH amendment, and removal of specific FCWU units (Requirements 1–4).","Staggered and conditional compliance deadlines (e.g. 65 landings; within 600 hours or by 30 June 2001; no later than 31 Dec 2000) (Compliance clauses 1(a)(b), 2, 4).","Different maintenance regimes depending on pre- or post-modification configuration (Pre-/Post-SB 27-008 configurations in Compliance 1(a)(b)).","Dependence on external documents and revisions (Pilatus Maintenance Manual TR 27-13, SB 27-008 Rev 2, SB 27-012, POH Temporary Revision No.15) and FOCA approval for later revisions (Requirement 1).","A serial-number based removal requirement (FCWU Part No. FCWU99-3, SN ≤ 100,000) creates inventory management and tracking burdens (Requirement 4).","Enforcement and approval discretion by the regulator and FOCA for acceptable manual revisions (Requirement 1; Note 1; Background).","Safety justification tied to mechanical failure modes that the flap control computer may not detect — technical risk requires physical inspection and hardware change (Background)."],"plain_english_summary":"This directive requires operators of all Pilatus PC-12 and PC-12/45 aeroplanes to inspect flap actuators for axial end-play and backlash, modify the flap system per a Pilatus service bulletin, update the Pilot’s Operating Handbook, and remove certain Flap Control and Warning Units (by serial number). It sets specific inspection intervals, retrofit timelines and removal deadlines to address detected gear wear and potential actuator failure that the regulator says could bypass computer detection."}},"importantCases":[],"_links":{"self":"/api/acts/ad-pc-12-13-amdt-1-flap-system","history":"/api/acts/ad-pc-12-13-amdt-1-flap-system/history","analysis":"/api/acts/ad-pc-12-13-amdt-1-flap-system/analysis","conflicts":"/api/acts/ad-pc-12-13-amdt-1-flap-system/conflicts","importantCases":"/api/acts/ad-pc-12-13-amdt-1-flap-system/important-cases","documents":"/api/acts/ad-pc-12-13-amdt-1-flap-system/documents"}}