{"id":"F2006B06079","name":"AD/PC-12/16 - Electrical Power - Generator No. 2 Excitation","slug":"ad-pc-12-16-electrical-power-generator-no-2-excitation","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":114477,"registerId":"commonwealth-F2006B06079-current","compilationNumber":null,"startDate":"2026-04-03","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/PC-12/16 - Electrical Power - Generator No. 2 Excitation","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)  \nPilatus PC-12 Series Aeroplanes\n\nAD/PC-12/16 Electrical Power \\- Generator No. 2 Excitation 4/99 TX\n\nApplicability: All Model PC-12 and PC-12/45 with Manufacturers Serial Numbers MSN 101 up to and including MSN 260.\n\nRequirement: 1. Modify the electrical power system in accordance with Pilatus PC-12 Service Bulletin (SB) No 24-012 dated 19 February 1999.\n\nNote: FOCA Switzerland AD HB 99-143 refers.\n\nCompliance: 1. For aeroplanes (MSN 231 and subsequent) with Bosch Generator No 2 Part Number (P/N) 524.32.12.158 installed or Pilatus PC-12 SB 24-010 incorporated \\- Within the next ten flights after the effective date of this Directive; or\n\nFor aeroplanes (MSN 101 up to and including MSN 230) with Electro Systems Generator No 2 P/N 978.87.24.121 and Pilatus PC-12 SB 24-009 incorporated - Within the next 100 hours time in service after the effective date of this directive.\n\nThis Airworthiness Directive becomes effective on 25 February 1999.\n\nBackground: The Generator No 2 control unit (VR231) does not prevent electrical feedback from the Generator No 2 field excitation on engine shut-down. If the Generator No 2 is not switched off prior to engine shut-down, voltage spikes may be created at relay K234, which could result in overheat damage to electrical components of the generator control unit.\n\nThis Directive requires modification of the electrical power system consisting of the removal of diodes (CR201 and 202) and the installation of a new five amp circuit breaker (CB235), together with a new suppression filter (A250). This modification is designed to minimise damage to the electrical system.","sortOrder":0}],"analysis":{"flash_summary_failed":{"failed":true,"reason":"Unauthenticated. Configure AI_GATEWAY_API_KEY or use a provider module. Learn more: https://ai-sdk.dev/unauthenticated-ai-gateway","source":"analysis-cron"},"kimi_summary":{"content_quality":"ok","complexity_score":3,"scope_assessment":{"changed":false,"description":"This is a discrete airworthiness directive with a narrow, specific safety purpose—modifying the Generator No. 2 excitation system to prevent electrical damage. It has not expanded beyond its original technical safety intent."},"complexity_factors":["Multiple conditional compliance paths based on manufacturer serial number (MSN) ranges and installed part numbers","Cross-reference to external technical documents (Pilatus Service Bulletin 24-012, plus referenced SB 24-010 and SB 24-009)","Technical aviation terminology requiring specialized knowledge (field excitation, voltage spikes, relay K234, suppression filter A250)","Dual effective date calculation method (flights vs. flight hours depending on aircraft configuration)"],"plain_english_summary":"This safety order requires owners/operators of Pilatus PC-12/45 aircraft (S/N 101–260) with Bosch or Electro Systems generators to modify the electrical system—removing diodes CR201/CR202 and installing a new circuit breaker and filter—to prevent voltage spikes that can overheat and damage Generator No. 2 when it isn’t switched off before engine shutdown.  \n\nCompliance deadlines vary by generator model and aircraft serial number."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":true,"description":"Alters the aircraft's original electrical configuration by mandating removal of existing diodes and installation of a new circuit breaker and suppression filter (Requirement; Background). The Directive narrows applicability to specific MSNs and Generator No.2 P/Ns and imposes binding compliance timeframes (Applicability; Compliance), shifting these aircraft from standard maintenance practice to a mandatory modification obligation effective 25 Feb 1999."},"complexity_factors":["Targeted applicability to a narrow serial range (MSN 101–260) and specific Generator No.2 part numbers (Applicability) increases administrative filtering required before compliance.","Two different compliance windows depending on MSN and generator P/N (ten flights vs 100 hours TIS) creates operational scheduling complexity (Compliance).","Mandates a specific shop action incorporating a manufacturer Service Bulletin (SB No 24‑012) rather than a performance-based fix, raising dependence on parts/workshop availability (Requirement).","Technical modification requires removal and installation of named components (CR201/202, CB235, A250), so maintenance must follow technical SB procedures and record changes (Requirement; Background).","Cross-reference to a foreign AD (FOCA Switzerland AD HB 99‑143) may require harmonised documentation or approvals in some registries (Note)."],"plain_english_summary":"Requires a physical modification to the Pilatus PC‑12 electrical system per Pilatus Service Bulletin No 24‑012: remove diodes CR201/202 and install a 5‑amp circuit breaker (CB235) and suppression filter (A250). This applies to PC‑12 and PC‑12/45 aircraft MSN 101–260 with specified Generator No.2 part numbers and must be completed within the stated flight/hour deadlines (effective 25 Feb 1999) to prevent voltage spikes on engine shutdown that can overheat generator control components and cause damage."}},"importantCases":[],"_links":{"self":"/api/acts/ad-pc-12-16-electrical-power-generator-no-2-excitation","history":"/api/acts/ad-pc-12-16-electrical-power-generator-no-2-excitation/history","analysis":"/api/acts/ad-pc-12-16-electrical-power-generator-no-2-excitation/analysis","conflicts":"/api/acts/ad-pc-12-16-electrical-power-generator-no-2-excitation/conflicts","importantCases":"/api/acts/ad-pc-12-16-electrical-power-generator-no-2-excitation/important-cases","documents":"/api/acts/ad-pc-12-16-electrical-power-generator-no-2-excitation/documents"}}