{"id":"F2006B04834","name":"AD/CA25/3 - Air Filter Box Rear Mounting Bracket","slug":"ad-ca25-3-air-filter-box-rear-mounting-bracket","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":44635,"registerId":"commonwealth-F2006B04834-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/CA25/3 - Air Filter Box Rear Mounting Bracket","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)  \nSkyfox Aviation (Hedaro) CA25 Series Aeroplanes\n\nAD/CA25/3 Air Filter Box Rear Mounting Bracket 1/96\n\nApplicability: CA25 Aircraft.\n\nRequirement: 1. Visually inspect the rivets securing the air filter box rear mounting bracket. If the rivets are loose, broken or missing, replace with MS20470AD4-4 solid rivets.\n\n2. Remove the air filter box from the aircraft and replace the pop rivets securing the rear mounting bracket with MS20470AD4-4 or MS20470AD5-4 solid rivets.\n\nNote: Skyfox Aviation Service Bulletin 9 Issue 2 refers.\n\nCompliance: For Requirement 1, before further flight after 4 January 1996.\n\nFor Requirement 2, at the next inspection for issue of a Maintenance Release or within 100 hours time in service, whichever occurs first.\n\nBackground: The pop rivets originally fitted could work loose and be ingested into the engine.\n\nThis AD requires fitment of solid rivets.","sortOrder":0}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a standard Airworthiness Directive (AD) — a targeted safety order for a specific aircraft part. It has not expanded beyond its original purpose of mandating a mechanical fix for a known defect. The scope remains tightly focused on the CA25 air filter box mounting bracket issue."},"complexity_factors":["Single aircraft type applicability (CA25 series only)","Two simple sequential requirements with clear deadlines","Only two defined technical terms (MS20470AD4-4 and MS20470AD5-4 rivet specifications)","No cross-references to other legislation or complex conditional logic","Single background note referencing a service bulletin","Straightforward compliance timeline with binary trigger (next inspection OR 100 hours)"],"plain_english_summary":"This is a **safety notice for a specific type of light aircraft** — the Skyfox Aviation CA25 series.\n\n**What it does:**\nIt orders owners and operators of these planes to **fix a dangerous design flaw** in how the air filter box is attached to the aircraft. The original \"pop rivets\" (a type of fastener that can loosen over time) must be replaced with stronger \"solid rivets\" that won't come loose.\n\n**Why it matters:**\nLoose rivets could fall off and get **sucked into the engine**, causing serious damage or engine failure while flying. This is a mandatory fix — you cannot legally fly the aircraft until at least the initial inspection is done.\n\n**Who must act:**\nAnyone who owns, operates, or maintains a CA25 aircraft.\n\n**What must be done:**\n- **Immediately** (before flying again after 4 January 1996): Check if the rivets are loose, broken, or missing. Replace any bad ones with solid rivets.\n- **Soon** (at the next scheduled maintenance check or within 100 flight hours, whichever comes first): Remove the air filter box entirely and replace all the pop rivets with solid ones.\n\n**The bottom line:**\nThis is a targeted mechanical fix to prevent engine damage. It's mandatory, time-sensitive, and relatively straightforward — but skipping it could be catastrophic."},"flash_summary":{"complexity_score":2,"scope_assessment":{"changed":false,"description":"The directive's scope is consistent with its stated purpose: it targets the air filter box rear mounting bracket rivets on CA25 aircraft and mandates inspection and replacement with specified solid rivets to prevent pop rivet ingestion. The instrument confines action to those parts and prescribes timing and rivet types (Applicability; Requirement 1; Requirement 2; Compliance), without expanding to other aircraft systems or broader operational rules."},"complexity_factors":["Narrow applicability: applies only to Skyfox (Hedaro) CA25 aircraft (Applicability).","Limited number of discrete actions: a visual inspection and a rivet replacement operation (Requirement 1; Requirement 2).","Prescriptive technical solution: specifies exact rivet part numbers to be used (MS20470AD4-4 or MS20470AD5-4) (Requirement 1; Requirement 2).","Clear compliance deadlines: immediate action before further flight for defective rivets and a defined maintenance window for full replacement (Compliance).","Dependency on a referenced service bulletin for implementation details (Note), which adds a single external technical reference."],"plain_english_summary":"Owners and maintenance organisations of CA25 (Skyfox/Hedaro) aeroplanes must inspect the rear air‑filter‑box mounting rivets and replace any loose/broken/missing pop rivets with specified MS20470 solid rivets, and at the next maintenance release (or within 100 flight hours) remove the box and replace all rear mounting pop rivets with solid rivets. The AD addresses a safety risk that pop rivets can work loose and be ingested into the engine; owners/operators pay and licensed maintainers must perform the work."}},"importantCases":[],"_links":{"self":"/api/acts/ad-ca25-3-air-filter-box-rear-mounting-bracket","history":"/api/acts/ad-ca25-3-air-filter-box-rear-mounting-bracket/history","analysis":"/api/acts/ad-ca25-3-air-filter-box-rear-mounting-bracket/analysis","conflicts":"/api/acts/ad-ca25-3-air-filter-box-rear-mounting-bracket/conflicts","importantCases":"/api/acts/ad-ca25-3-air-filter-box-rear-mounting-bracket/important-cases","documents":"/api/acts/ad-ca25-3-air-filter-box-rear-mounting-bracket/documents"}}