{"id":"F2006B11281","name":"AD/ML-M4/12 - Bucket Seats Retention - Inspection","slug":"ad-ml-m4-12-bucket-seats-retention-inspection","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":57090,"registerId":"commonwealth-F2006B11281-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/ML-M4/12 - Bucket Seats Retention - Inspection","content":"---\nmeta-content-style-type: text/css\nmeta-content-type: application/xhtml+xml; charset=utf-8\nmeta-generator: Aspose.Words for .NET 22.10.0\n---\n\n?xml version=\"1.0\" encoding=\"utf-8\" standalone=\"no\"?>\n\nCOMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\n \n\n![](image.001.png)  Maule M-4 Series Aeroplanes\n\n \n\nAD/ML-M4/12 Bucket Seats Retention - Inspection 10/78\n\nApplicability: All model M-4-180C with S/Nos. 3001C to 3004C; All model M-4-220C with S/Nos. 2044C to 2060C.\n\nDocument: Maule SL No. 21.\n\n \n\nCompliance: Within 25 hours time in service after 20 September 1978.\n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n","sortOrder":0}],"analysis":{"flash_summary":{"complexity_score":2,"scope_assessment":{"changed":false,"description":"Nothing in the supplied text indicates that the directive's scope was altered from its original form. The instrument as presented applies only to the listed serial-numbered aircraft, references Maule SL No. 21 for inspection procedure, and sets the compliance deadline as within 25 hours TIS after 20 September 1978. No amendments, expansions, or narrowing of applicability are shown in the provided text."},"complexity_factors":["Very narrow applicability: specific aircraft models and tightly defined serial-number ranges (reduces scope complexity but increases targeted administrative tracking). (Applicability.)","Short, fixed compliance window (25 hours time in service after 20 September 1978) creates scheduling pressure. (Compliance.)","Procedural detail is delegated to an external document (Maule SL No. 21), creating a dependency on that document for technical steps and any remedial actions. (Document.)","Directive text provided does not state corrective actions if inspection finds defects, requiring reliance on the manufacturer's procedure or further regulatory guidance (adds implementation uncertainty).","Administrative tasks: operators must arrange inspection, possible repairs, and retain evidence of compliance for oversight (operational burden)."],"plain_english_summary":"- What this instrument does mechanically\n  - This is an airworthiness directive titled \"AD/ML-M4/12 Bucket Seats Retention - Inspection\". It requires an inspection of the bucket-seat retention on a defined set of Maule M-4 series aeroplanes. (See: \"AD/ML-M4/12 Bucket Seats Retention - Inspection 10/78\".)\n\n- Who it affects\n  - Owners and operators of the specific aircraft listed: all M-4-180C with serial numbers 3001C to 3004C, and all M-4-220C with serial numbers 2044C to 2060C. (See: \"Applicability\".)\n  - The maintenance organisations and persons who carry out required inspections and any follow-up work determined by that inspection. (Implied by the obligation to inspect and by the reference to the manufacturer's service leaflet.)\n\n- What must be done and when\n  - The directive requires the inspection to be carried out in accordance with the referenced document (Maule Service Letter No. 21). (See: \"Document: Maule SL No. 21.\")\n  - The inspection must be completed within 25 hours time in service after 20 September 1978. (See: \"Compliance: Within 25 hours time in service after 20 September 1978.\")\n\n- Why the instrument exists (official claim and its operational implications)\n  - The title and the reference to a manufacturer's service letter indicate the directive's stated purpose is to verify the retention arrangement for the bucket seats on the listed aircraft. That is the official objective as presented by the document. (See: title and \"Document\".)\n  - Operationally, that objective means aircraft covered by the Applicability must be taken out of service or scheduled for maintenance to allow the inspection within the stated short window; if the inspection identifies defects, additional corrective work (parts, labour, and possibly additional grounding time) will be required. The directive does not itself set out corrective steps in the text shown; it delegates procedural detail to Maule SL No. 21. (See: \"Document: Maule SL No. 21.\" )\n\n- Who pays, who decides, and what behaviour changes\n  - Who pays: owners/operators bear direct costs (inspection labour, possible parts and repair, aircraft downtime). Maintenance organisations receive payment for work performed. Any parts or specialist labour costs are likewise borne by the operator unless contracted otherwise. (Inferred from the requirement to perform inspection and any follow-up.)\n  - Who decides: the regulator issued the directive; operators decide which approved maintenance provider carries out the inspection and any remedial work; the referenced manufacturer's service letter provides the technical steps to follow. (See: directive title, \"Applicability\", and \"Document\".)\n  - Behaviour changes: operators must schedule an inspection within 25 hours TIS of 20 Sep 1978; maintenance providers must perform the inspection to the manufacturer’s procedure; operators will need to keep evidence of compliance as part of normal airworthiness records. (See: \"Compliance\" and \"Document\".)\n\n- Implementation, compliance and trade-offs to note\n  - Implementation dependency: the directive relies on Maule SL No. 21 for procedural detail. If that external document is not available or is ambiguous, implementers must seek that information before or during compliance. (See: \"Document: Maule SL No. 21.\")\n  - Short compliance window: the 25-hour time-in-service window after a fixed date creates a tight scheduling requirement and may force near-term aircraft downtime. (See: \"Compliance\".)\n  - Concentrated scope: the directive applies only to a small, specifically identified set of serial numbers, concentrating the regulatory obligation on a small group of operators. (See: \"Applicability\".)\n  - Potential follow-on costs: the directive as provided does not state corrective remedies; if the inspection finds defects, operators will face additional costs and possible longer grounding while parts or repairs are arranged. (Implied by the inspection requirement and reference to the manufacturer's service letter.)\n  - Enforcement and record-keeping: compliance will be relevant to continuing airworthiness oversight; operators should retain evidence of the inspection and any corrective action in aircraft records. (Implied by the nature of airworthiness directives and the listed compliance requirement.)"},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a discrete, targeted safety directive addressing a specific mechanical defect in a limited fleet of aircraft. It has not expanded beyond its original purpose of ensuring seat retention integrity in the specified Maule models."},"complexity_factors":["Extremely short document (under 200 words)","Only 2 defined applicability criteria (specific serial number ranges)","Single compliance requirement with clear deadline","No cross-references to other legislation beyond the parent Civil Aviation Regulations 1998","No conditional logic or exceptions","References only one external technical document (Maule SL No. 21)"],"plain_english_summary":"This is an **Airworthiness Directive** (a mandatory safety order) issued by Australia's Civil Aviation Safety Authority for specific Maule M-4 series aeroplanes.\n\n**What it does:**\n- Requires owners/operators of certain Maule M-4 aircraft to inspect the **bucket seats retention** (how the seats are secured to the floor) to ensure they won't fail in flight.\n\n**Who it affects:**\n- Owners and operators of:\n  - Maule M-4-180C aircraft with serial numbers 3001C through 3004C\n  - Maule M-4-220C aircraft with serial numbers 2044C through 2060C\n\n**What must be done:**\n- Follow the instructions in **Maule Service Letter No. 21** (the manufacturer's official guidance)\n- Complete the inspection **within 25 hours of flying time** after 20 September 1978\n\n**Why it matters:**\nLoose or improperly retained seats could shift or detach during flight, potentially causing loss of control or injury. This directive ensures a known defect is fixed before it causes an accident."}},"importantCases":[],"_links":{"self":"/api/acts/ad-ml-m4-12-bucket-seats-retention-inspection","history":"/api/acts/ad-ml-m4-12-bucket-seats-retention-inspection/history","analysis":"/api/acts/ad-ml-m4-12-bucket-seats-retention-inspection/analysis","conflicts":"/api/acts/ad-ml-m4-12-bucket-seats-retention-inspection/conflicts","importantCases":"/api/acts/ad-ml-m4-12-bucket-seats-retention-inspection/important-cases","documents":"/api/acts/ad-ml-m4-12-bucket-seats-retention-inspection/documents"}}