{"id":"F2006B09083","name":"AD/DHC-3/33 - Wing Strut to Fuselage Tie Bar","slug":"ad-dhc-3-33-wing-strut-to-fuselage-tie-bar","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":115636,"registerId":"commonwealth-F2006B09083-current","compilationNumber":null,"startDate":"2026-04-03","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/DHC-3/33 - Wing Strut to Fuselage Tie Bar","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)  DHC-3 (Otter) Series Aeroplanes\n\n \n\nAD/DHC-3/33 Wing Strut to Fuselage Tie Bar 13/87\n\nApplicability: All models.\n\n \n\nRequirement: Action in accordance with de Havilland Canada SB 3/37 Rev B.\n\n \n\nNote: Canadian AD CF-82-26 refers.\n\n \n\nCompliance: Prior to the initial issue of a Certificate of Airworthiness and thereafter at periods not exceeding 12 months.\n\n \n\nBackground: Tie bar lugs have been found corroded as well as the internal channel section under the cabin floor.\n\n \n","sortOrder":0}],"analysis":{"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The text sets a clear, bounded safety requirement for DHC-3 series aeroplanes: comply with de Havilland Canada SB 3/37 Rev B and meet the timing requirements (before initial Certificate of Airworthiness and then at intervals not exceeding 12 months). The instrument itself does not indicate any expansion or narrowing of scope from an earlier or original intent; it applies to all models and prescribes the referenced technical standard and the compliance frequency. (\"Applicability\"; \"Requirement\"; \"Compliance\"; \"Background\"; \"Note\")"},"complexity_factors":["Direct, single-subject requirement (inspection/repair of wing strut to fuselage tie bar). (\"Requirement\"; \"Background\")","Reference to an external document (de Havilland Canada SB 3/37 Rev B) for technical details, requiring readers to consult that SB for exact work scope. (\"Requirement\")","Mandatory timing tied to certification and annual intervals (prior to initial Certificate of Airworthiness; thereafter <= 12 months). (\"Compliance\")","Applicability to all models of the type (broad applicability increases number of affected operators). (\"Applicability\")","Cross-reference to an overseas AD (Canadian AD CF-82-26) which may require coordination for technical interpretation. (\"Note\")"],"plain_english_summary":"This airworthiness directive mandates inspections and any corrective work on the wing strut–fuselage tie bar on all de Havilland Canada DHC‑3 (Otter) aircraft, by requiring compliance with de Havilland Canada SB 3/37 Rev B.  \n\nIt responds to discovered corrosion, must be done before initial Certificate of Airworthiness and then at least annually, and imposes costs on owners/operators while maintenance organisations carry out the work."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a discrete, targeted safety directive focused on a specific structural defect in a single aircraft type. It has not expanded beyond its original purpose of addressing corrosion in the wing strut tie bar."},"complexity_factors":["Very short document (under 200 words)","Only 1 substantive requirement (follow the Canadian manufacturer's Service Bulletin)","No defined terms section","No cross-references to other legislation (only a reference to a Canadian AD and manufacturer bulletin)","Simple compliance structure: one-time check plus annual recurrence","Single applicability criterion (all models)"],"plain_english_summary":"This is an **Airworthiness Directive (AD)** — a mandatory safety order issued by Australia's Civil Aviation Safety Authority (CASA). It applies to all models of the **de Havilland Canada DHC-3 Otter** aircraft.\n\n**What it does:**\n- Requires aircraft owners/operators to inspect and maintain a specific structural component called the **\"wing strut to fuselage tie bar\"** — a metal bar that helps connect the wing support strut to the aircraft's body.\n- The work must follow the manufacturer's official instructions (Service Bulletin 3/37 Revision B).\n\n**Why it matters:**\n- **Corrosion was found** in the tie bar lugs (attachment points) and in a hidden internal channel under the cabin floor. Corrosion in structural parts can weaken the aircraft and lead to failure.\n- This is a **preventive safety measure** to catch problems before they become dangerous.\n\n**Who must comply:**\n- Anyone operating a DHC-3 Otter aircraft in Australia.\n\n**When:**\n- Before the aircraft first gets its Australian airworthiness certificate, and **every 12 months** after that."}},"importantCases":[],"_links":{"self":"/api/acts/ad-dhc-3-33-wing-strut-to-fuselage-tie-bar","history":"/api/acts/ad-dhc-3-33-wing-strut-to-fuselage-tie-bar/history","analysis":"/api/acts/ad-dhc-3-33-wing-strut-to-fuselage-tie-bar/analysis","conflicts":"/api/acts/ad-dhc-3-33-wing-strut-to-fuselage-tie-bar/conflicts","importantCases":"/api/acts/ad-dhc-3-33-wing-strut-to-fuselage-tie-bar/important-cases","documents":"/api/acts/ad-dhc-3-33-wing-strut-to-fuselage-tie-bar/documents"}}