{"id":"F2005L02050","name":"AD/PC-12/47 - Main Landing Gear Special Bolt Assembly","slug":"ad-pc-12-47-main-landing-gear-special-bolt-assembly","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":36218,"registerId":"commonwealth-F2005L02050-current","compilationNumber":null,"startDate":"2026-04-01","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"Pilatus PC-12 Series Aeroplanes","sectionType":"division","heading":"Pilatus PC-12 Series Aeroplanes","content":"### Pilatus PC-12 Series Aeroplanes\n\n| AD/PC-12/47 | Main Landing Gear Special Bolt Assembly | 9/2005 |\n| ----------- | --------------------------------------- | ------ |\n\n| Applicability: | Model PC-12 and PC-12/45 aircraft, manufacturer serial numbers MSN 101 through MSN 620; equipped with the following main landing gear (MLG) assemblies and special bolts:MLG assemblies part number (P/N) 532.10.12.049 and P/N 532.10.12.050 delivered before 31 December 2004.Special bolts P/N 532.10.12.077 delivered before 31 December 2004.                                                                                                                                              |\n| -------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n| Requirement:   | In accordance with Pilatus PC-12 Service Bulletin No. 32-018; perform an inspection of the left and right MLG assemblies to determine if there are bolts with P/N 532.10.12.077 installed that do not have white primed and painted heads.If the inspection reveals any P/N 532.10.12.077 bolts without white primed and painted heads, before further flight, replace the affected bolts with new P/N 532.10.12.077F bolts in all MLG assemblies.Note: Switzerland FOCA AD HB-2005-288 refers. |\n| Compliance:    | Within 100 hours time in service or 3 calendar months after 1 September 2005, whichever occurs first.                                                                                                                                                                                                                                                                                                                                                                                           |\n|                | This Airworthiness Directive becomes effective on 1 September 2005.                                                                                                                                                                                                                                                                                                                                                                                                                             |\n| Background:    | The separation of a part number 532.10.12.077 bolt head occurred in the main landing gear assembly of a specified manufacturer. Investigation revealed the cause as corrosion of the bolt, which occurred because the bolt head was not primed and painted. This condition can decrease the specified fatigue life and could lead to main landing gear collapse during operation with consequent loss of aircraft control.                                                                      |\n\n![](image.001.png)  \nDavid Villiers  \nDelegate of the Civil Aviation Safety Authority\n\n20 July 2005","sortOrder":0},{"sectionNumber":"AD/PC-12/47","sectionType":"part","heading":"AD/PC-12/47","content":"## AD/PC-12/47","sortOrder":1},{"sectionNumber":"Main Landing Gear Special Bolt Assembly","sectionType":"part","heading":"Main Landing Gear Special Bolt Assembly","content":"## Main Landing Gear Special Bolt Assembly","sortOrder":2},{"sectionNumber":"9/2005","sectionType":"part","heading":"9/2005","content":"## 9/2005","sortOrder":3}],"analysis":{"flash_summary":{"complexity_score":2,"scope_assessment":{"changed":false,"description":"This AD is tightly focused on a single, identified safety hazard (corrosion-related bolt-head separation) and mandates inspection and replacement to remove the hazard. It does not expand beyond that original safety remedial purpose: the requirements, applicability limits, and remedies are consistent with addressing the identified failure mode and do not introduce broader regulatory obligations or additional unrelated compliance burdens."},"complexity_factors":["Single narrow subject (main landing gear bolt) with a single corrective action (inspect and replace).","Applicability limited by serial number range (MSN 101–620) and delivery date cut-off (MLG assemblies and bolts delivered before 31 Dec 2004).","References to external document: Pilatus Service Bulletin No. 32-018 required for procedure details (cross-reference increases administrative complexity).","One conditional compliance window (whichever occurs first: 100 flight hours or 3 calendar months after 1 Sep 2005).","Specific part numbers for the suspect part (P/N 532.10.12.077) and mandatory replacement part (P/N 532.10.12.077F).","A single safety root cause and single mitigation, with no nested exceptions or multiple pathways."],"plain_english_summary":"**What this instrument does (mechanically)**\n\n- It orders owners/operators of certain Pilatus PC-12 and PC-12/45 aeroplanes to inspect the left and right main landing gear (MLG) for a specific bolt (part number 532.10.12.077) that does not have a white primed and painted head and, if any such bolts are found, to replace them with a specified replacement bolt (P/N 532.10.12.077F) before the aircraft flies again. (Requirement)\n- The inspection and any required replacements must be done in accordance with Pilatus PC-12 Service Bulletin No. 32-018. (Requirement)\n- The AD applies to PC-12 and PC-12/45 aircraft with manufacturer serial numbers (MSN) 101 through 620, but only where the affected MLG assemblies (P/N 532.10.12.049 or P/N 532.10.12.050) or the suspect bolts (P/N 532.10.12.077) were delivered before 31 December 2004. (Applicability)\n- The work must be completed within 100 hours time in service or within 3 calendar months after 1 September 2005, whichever comes first. The AD became effective on 1 September 2005. (Compliance)\n\n**Who this affects**\n\n- Aircraft owners and operators of Pilatus PC-12 and PC-12/45 aeroplanes with MSNs 101–620 that have the specified MLG assemblies or bolts delivered before 31 Dec 2004. (Applicability)\n- Maintenance organisations and licensed engineers who must perform the inspection and replacement to an approved standard and record compliance. (Requirement)\n\n**Why it matters (stated safety concern and mechanism)**\n\n- The directive responds to an incident where a bolt head (P/N 532.10.12.077) separated in a main landing gear assembly due to corrosion. Investigation concluded the bolt head had not been primed and painted, which allowed corrosion that reduced the bolt’s fatigue life. If such bolts fail in service, the MLG could collapse and the aircraft could be lost of control. (Background)\n\n**Immediate obligations and operational effect**\n\n- Inspect both left and right MLG assemblies for P/N 532.10.12.077 bolts without white primed and painted heads. (Requirement)\n- If any are found, replace them with P/N 532.10.12.077F bolts before further flight. (Requirement)\n- Follow Pilatus Service Bulletin No. 32-018 for the method and any additional instructions. (Requirement)\n\n**Who pays and who decides**\n\n- The financial cost (parts and labour) falls on the aircraft owner/operator; any downtime for inspection and replacement is borne by the operator. (Requirement, Compliance)\n- The technical decision about how to carry out the inspection and replacement is exercised by the maintenance organisation or licensed engineers in accordance with the Pilatus service bulletin and applicable aviation maintenance regulations. The regulator (CASA delegate) issued the AD. (Requirement)\n\n**Costs, incentives and trade-offs**\n\n- Direct costs: inspection labour, possible replacement bolts (P/N 532.10.12.077F), and aircraft downtime while the work is done. (Requirement, Compliance)\n- Incentive effects: operators with many affected aircraft incur repeated costs; the supplier of the replacement bolt obtains concentrate demand for the new part. Operators may need to prioritise aircraft scheduling to meet the short compliance window (100 hours TIS or 3 months). (Compliance)\n- Implementation risks: availability of replacement parts, clarity on what constitutes an acceptable painted head, and the need to follow the referenced service bulletin correctly. If replacement parts are scarce, operators could face grounded aircraft for longer. (Requirement)\n\n**Compliance and enforcement**\n\n- Compliance is mandatory within the stated time limits. The AD references a Pilatus service bulletin for technical procedures, and non-compliance would be a regulatory matter. (Requirement, Compliance)\n\n**Notes on provenance and cross-reference**\n\n- The AD notes a corresponding Swiss FOCA AD (HB-2005-288) and relies on a manufacturer service bulletin for the technical steps. That means the AD’s practical implementation depends on the content and availability of that bulletin and on supply of the specified replacement bolts. (Requirement, Note)\n\n"},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a targeted safety directive addressing a specific mechanical defect in a specific aircraft type. The scope remains precisely focused on the bolt corrosion issue identified in the background section."},"complexity_factors":["Single, specific mechanical issue (bolt corrosion)","Clear applicability criteria (specific aircraft models and serial numbers)","Straightforward two-step requirement: inspect, then replace if necessary","Only 2 part numbers referenced in the main requirement","Single compliance deadline with simple alternative calculation","No nested exceptions or conditional logic","Minimal cross-referencing (one service bulletin and one foreign AD mentioned)","Short document (approximately 200 words of substantive content)"],"plain_english_summary":"Owners/operators of Pilatus PC‑12/PC‑12‑45 (S/N 101–620) must inspect left and right main landing gear bolts for white‑primed/painted heads and, if bolts (P/N 532.10.12.077) lack the white finish, replace them with new bolts (P/N 532.10.12.077F) before next flight. This AD responds to bolt corrosion that could cause gear failure. Deadline: within 100 flight hours or 3 months after 1 Sep 2005."},"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-12-47-main-landing-gear-special-bolt-assembly","history":"/api/acts/ad-pc-12-47-main-landing-gear-special-bolt-assembly/history","analysis":"/api/acts/ad-pc-12-47-main-landing-gear-special-bolt-assembly/analysis","conflicts":"/api/acts/ad-pc-12-47-main-landing-gear-special-bolt-assembly/conflicts","importantCases":"/api/acts/ad-pc-12-47-main-landing-gear-special-bolt-assembly/important-cases","documents":"/api/acts/ad-pc-12-47-main-landing-gear-special-bolt-assembly/documents"}}