{"id":"F2006B08795","name":"AD/DC3/18 - Flap Mechanism Attachment Angle - Inspection","slug":"ad-dc3-18-flap-mechanism-attachment-angle-inspection","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":52148,"registerId":"commonwealth-F2006B08795-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/DC3/18 - Flap Mechanism Attachment Angle - 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)  Douglas DC3 Series Aeroplanes\n\n \n\nAD/DC3/18 Flap Mechanism Attachment Angle - Inspection NK\n\nDocument: 1. Douglas SB (DC3) No. 216 Section 1 Supplement to SB dated 16 April 1945; or\n\n \n\n2. FAA AD 44-7-2; or 3. ANO 105.1.16.1.6.3.\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\n \n","sortOrder":0}],"analysis":{"flash_summary":{"complexity_score":4,"scope_assessment":{"changed":false,"description":"The AD as presented requires inspection of the flap mechanism attachment angle for Douglas DC-3 series aeroplanes and does so by referring to pre-existing technical documents (Douglas SB No. 216 supplement, FAA AD 44-7-2, or ANO 105.1.16.1.6.3). There is no indication in the text supplied that the AD expands or narrows the set of affected components, aircraft, or required actions compared with the cited technical references. The instrument continues the original safety‑action approach of mandating inspection via established service/AD material. (Source: AD/DC3/18 and Document list.)"},"complexity_factors":["Narrow technical scope (single component: flap mechanism attachment angle) reduces breadth of issues.","Dependence on external historical and foreign documents (Douglas SB No. 216 dated 1945; FAA AD 44-7-2; ANO 105.1.16.1.6.3) increases administrative and interpretive burden.","Lack of procedural detail in the AD text itself — implementers must consult referenced documents for step‑by‑step actions.","Applicability to an older aircraft type (Douglas DC-3 series) can complicate parts availability and repair options.","Regulatory enforcement under Part 39 creates a clear compliance obligation but requires recordkeeping and proof of conformity."],"plain_english_summary":"What this instrument does (mechanical change)\n\n- The instrument AD/DC3/18 requires an inspection of the flap mechanism attachment angle on Douglas DC‑3 series aeroplanes. The inspection must be carried out in accordance with one of the documents listed in the AD: (1) Douglas Service Bulletin (DC3) No. 216 Section 1 Supplement dated 16 April 1945; or (2) FAA Airworthiness Directive 44‑7‑2; or (3) ANO 105.1.16.1.6.3. (Source: AD/DC3/18, Document list.)\n\nWho it affects\n\n- Owners and operators of Douglas DC‑3 series aeroplanes registered in Australia. (Source: AD title and applicability to Douglas DC3 series.)\n- Approved maintenance organisations and engineers who must perform the inspection and any corrective work following the referenced documents. (Source: Document list and nature of airworthiness directives.)\n- The Civil Aviation Safety Authority (CASA) as the issuing regulator under the Civil Aviation Regulations 1998, Part 39 (Schedule of Airworthiness Directives). (Source: header: Part 39; AD listing.)\n\nWhy it matters (official rationale and mechanical effect)\n\n- The AD directs a specific safety inspection: checking the flap mechanism attachment angle. The official intent (as with airworthiness directives generally) is to identify and, if necessary, correct any condition that might affect safe operation. The AD implements that intent by mandating inspections following the technical procedures in one of the three referenced documents. (Source: AD title and Document list.)\n\nCosts, incentives and who pays\n\n- Operators pay for the inspection and for any repairs or part replacements found necessary by the inspection. (Mechanism: compliance typically requires labour, parts, and aircraft time.) (Source: AD nature and inspection requirement.)\n- Maintenance organisations receive work from operators to carry out inspections but must also ensure they have access to and apply the correct historical technical material listed in the AD. (Source: Document list.)\n\nCompliance burden, discretion and implementation risk\n\n- The AD does not itself include technical steps in the text provided; it points to external documents. That means maintenance personnel must obtain and follow one of the referenced documents (Douglas SB No. 216 Section 1 supplement dated 16 April 1945, FAA AD 44‑7‑2, or ANO 105.1.16.1.6.3). The need to consult older or foreign-issued documents increases the administrative burden and may require interpretation by qualified maintenance engineers. (Source: Document list.)\n- CASA enforces compliance under Part 39, so operators must demonstrate inspection and corrective action as required. (Source: header: Civil Aviation Regulations 1998, Part 39.)\n\nBehavioural effects and trade-offs\n\n- Operators must schedule inspections into maintenance programmes and accept the opportunity cost of aircraft downtime while inspections/repairs occur. (Mechanism: mandatory AD compliance obliges inspection and corrective action.) (Source: AD nature.)\n- The AD gives several alternative documents as compliance paths. That provides some flexibility in which technical procedure to follow, but it also requires choosing and following the correct reference. (Source: Document list.)\n\nConcrete mechanism and decision authority\n\n- The AD prescribes the action (inspection of flap mechanism attachment angle) and cites the acceptable technical references. Compliance is required of operators; maintenance organisations perform the work; CASA is the regulator requiring compliance under Part 39. Repair or replacement decisions following the inspection are implemented by the operator/maintenance organisation in accordance with the referenced documents. (Source: AD/DC3/18 and Part 39 header.)"},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a discrete, targeted airworthiness directive focused on a specific mechanical component of a specific aircraft type. It has not expanded beyond its original purpose of ensuring flap mechanism integrity in DC-3 aircraft."},"complexity_factors":["Extremely short document — essentially a reference to external technical standards rather than substantive regulatory text","Only one substantive requirement (inspect the flap mechanism attachment angle)","Three alternative compliance pathways provided, but no conditional logic or exceptions","No defined terms section — relies entirely on external documents for technical specifications","No cross-referencing within the instrument itself — all technical detail outsourced to Douglas SB, FAA AD, or ANO"],"plain_english_summary":"This is an **Airworthiness Directive (AD)** for **Douglas DC-3 aircraft** — specifically regarding the **flap mechanism attachment angle**.\n\n**What it does:**\n- Requires owners and operators of DC-3 aeroplanes to inspect the **flap mechanism attachment angle** — a structural component that connects the wing flaps (the moving surfaces on the back of the wings that help with takeoff and landing) to the aircraft's wing structure.\n\n**Why it matters:**\n- Flap mechanism failures can be catastrophic. If the attachment angle cracks or fails, the pilot could lose control of the flaps during critical flight phases like landing.\n- This AD mandates compliance with one of three technical documents to ensure this component is inspected and maintained properly.\n\n**Who must comply:**\n- Anyone operating a **Douglas DC-3 series aircraft** in Australia.\n\n**Compliance documents (you must follow one of these):**\n1. **Douglas Service Bulletin (SB) No. 216, Section 1** — a manufacturer-issued maintenance notice from April 1945; or\n2. **FAA AD 44-7-2** — the equivalent US Federal Aviation Administration directive; or\n3. **ANO 105.1.16.1.6.3** — an Australian National Order (older aviation regulation).\n\n**In short:** If you fly or maintain a DC-3 in Australia, you must check this specific part of the wing flap system according to one of these three approved methods."}},"importantCases":[],"_links":{"self":"/api/acts/ad-dc3-18-flap-mechanism-attachment-angle-inspection","history":"/api/acts/ad-dc3-18-flap-mechanism-attachment-angle-inspection/history","analysis":"/api/acts/ad-dc3-18-flap-mechanism-attachment-angle-inspection/analysis","conflicts":"/api/acts/ad-dc3-18-flap-mechanism-attachment-angle-inspection/conflicts","importantCases":"/api/acts/ad-dc3-18-flap-mechanism-attachment-angle-inspection/important-cases","documents":"/api/acts/ad-dc3-18-flap-mechanism-attachment-angle-inspection/documents"}}