{"id":"F2006B06089","name":"AD/PC-12/27 Amdt 1 - Flap System Limitation","slug":"ad-pc-12-27-amdt-1-flap-system-limitation","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":114487,"registerId":"commonwealth-F2006B06089-current","compilationNumber":null,"startDate":"2026-04-03","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/PC-12/27 Amdt 1 - Flap System Limitation","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.003.png)For the reasons set out in the background section, the CASA delegate whose signature appears below revokes Airworthiness Directive (AD) AD/PC-12/27 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\nApplicability: PC-12 and PC-12/45 series aeroplanes with manufacturer serial numbers MSN 101 up to and including MSN 400.\n\n![](image.004.png)Requirement: 1. Insert Temporary Revision No 32 in the Pilot’s Operating Handbook/Aircraft Flight manual (POH/AFM).\n\n2. Install the flap system Primary Drive Unit field control panel and modify the flap control wiring in accordance with the Accomplishment Instructions of Pilatus PC- 12 service Bulletin 27-011 Revision 1 dated 26 January 2001.\n\nTemporary Revision No 32 may be removed from the POH/AFM following accomplishment of Requirement 2.\n\nNote: FOCA Switzerland AD HB 2001-070 refers.\n\nCompliance: For Requirement 1 \\- Remains unchanged as ‘Before further flight after 14 February 2001’.\n\nFor Requirement 2 \\- Within 50 hours time in service or 30 days after the effective date of this Directive, whichever occurs first.\n\nThis amendment becomes effective on 21 February 2001.\n\nBackground: The Swiss Federal Office for Civil Aviation (FOCA) has advised that during system maintenance it was found that certain failures of the flap system Primary Drive Unit motor contactor could result in uncommanded cycling of the flaps between 40º and selected positions. Investigation revealed that that current surges were being generated due to the motor coil power being removed after the field coil power was removed or reversed. These surges can cause the contactor to fail in the closed position which could cause cycling of the flaps.\n\n![](image.005.png)The original issue of this Directive required a Temporary Revision to be inserted in the POH/AFM which introduced limitations on operation of the flaps.\n\nCOMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 \\- 105 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\nThis amendment introduces a modification which provides terminating action for the POH/AFM flap operating limitations introduced by Temporary Revision 32.\n\nThe original issue of this Directive became effective on 14 February 2001.\n\n![Signature of Eugene Paul Holzapfel, Delegate of the Civil Aviation Safety Authority.](image.006.png)  \n\nEugene Paul Holzapfel\n\nDelegate of the Civil Aviation Safety Authority 15 February 2001\n\n![](image.002.png)  \n\nThe above AD is notified in the Commonwealth of Australia Gazette on 21 February 2001.","sortOrder":0}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This amendment remains tightly focused on its original purpose: correcting the unsafe flap system condition in specific PC-12 aircraft. The amendment simply adds a terminating action (the permanent hardware fix) to the original temporary flight manual limitation, without expanding beyond the original safety issue."},"complexity_factors":["Single, clearly defined applicability (specific serial number range)","Two straightforward requirements with clear compliance deadlines","Minimal cross-referencing (only to Pilatus Service Bulletin 27-011 and Swiss FOCA AD)","No nested conditions or exceptions","Short document (approximately 300 words)","Only one defined term used (POH/AFM - explained in text)"],"plain_english_summary":"This CASA safety order applies to Pilatus PC‑12 aircraft serial numbers 101–400 and addresses a hazardous electrical fault in the flap system that can make flaps cycle uncontrollably between 40° and the selected position. It requires pilots to insert a temporary flight‑manual revision before flying after 14 Feb 2001 (restricting flap use) and mandates a permanent modification—new control panel and rewiring per Pilatus Service Bulletin 27‑011—within 50 flight hours or 30 days."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":true,"description":"Yes. The amendment replaces the original AD's temporary POH flap operating limitations by adding a mandated modification (installation of the flap Primary Drive Unit field control panel and wiring changes per Pilatus SB 27‑011 Rev 1) that, once completed, allows removal of the temporary POH restriction. Applicability (MSN 101–400) and the specified compliance timing accompany the change."},"complexity_factors":["Technical modification required: install field control panel and rewire flap control per Pilatus SB 27-011 Rev 1 (Requirement 2).","Short compliance window for modification: within 50 flight hours or 30 days, whichever is first (Compliance).","Interim operational constraint: temporary POH/AFM revision must be inserted before further flight (Requirement 1).","Applicability limited to specific airframe serial numbers (MSN 101–400), requiring operators to track affected fleet.","AD revokes prior directive and provides a terminating action for the temporary limitation, creating a two-step compliance pathway.","Dependence on external technical documents and a foreign regulator reference (Pilatus SB and FOCA AD) for the required corrective steps."],"plain_english_summary":"This Airworthiness Directive for Pilatus PC‑12 (MSN 101–400) requires operators to insert a temporary flap‑limitation POH/AFM revision and then modify the flap Primary Drive Unit by installing a field control panel and changing wiring per Pilatus Service Bulletin 27‑011 Rev 1. CASA states the work prevents uncommanded flap cycling caused by a contactor failure. Operators must carry out the modification within the stated compliance window, after which the temporary POH limitation can be removed."},"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"}},"importantCases":[],"_links":{"self":"/api/acts/ad-pc-12-27-amdt-1-flap-system-limitation","history":"/api/acts/ad-pc-12-27-amdt-1-flap-system-limitation/history","analysis":"/api/acts/ad-pc-12-27-amdt-1-flap-system-limitation/analysis","conflicts":"/api/acts/ad-pc-12-27-amdt-1-flap-system-limitation/conflicts","importantCases":"/api/acts/ad-pc-12-27-amdt-1-flap-system-limitation/important-cases","documents":"/api/acts/ad-pc-12-27-amdt-1-flap-system-limitation/documents"}}