{"id":"F2006B09102","name":"AD/DHC-6/15 Amdt 1 - Wing Strut Jo-Bolt - Inspection","slug":"ad-dhc-6-15-amdt-1-wing-strut-jo-bolt-inspection","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":115655,"registerId":"commonwealth-F2006B09102-current","compilationNumber":null,"startDate":"2026-04-03","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/DHC-6/15 Amdt 1 - Wing Strut Jo-Bolt - Inspection","content":"---\nmeta-content-style-type: text/css\nmeta-content-type: application/xhtml+xml; charset=utf-8\nmeta-description: CASA Airworthiness Directive\nmeta-generator: Aspose.Words for .NET 22.10.0\nmeta-keywords: Issue 1/1983,Aircraft below 5700 kg,DHC-6 (Twin Otter) Series Aeroplanes,Wing Strut Jo-Bolt - Inspection,15 Amdt 1\ntitle: Airworthiness Directive - AD/DHC-6/15 Amdt 1 - Wing Strut Jo-Bolt - Inspection\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-6 (Twin Otter) Series Aeroplanes\n\n \n\nAD/DHC-6/15\n\nAmdt 1\n\n\nWing Strut Jo-Bolt - Inspection 1/83\n\n \n\nApplicability: All models with S/Nos. 1 to 170.\n\n \n\nDocument: De Havilland Aircraft of Canada SB No. 6/166, Rev. B. Compliance:  As detailed in the requirement document.\n\nBackground: AD revised to reflect requirement document revision status.\n\n \n","sortOrder":0}],"analysis":{"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The amendment updates the AD to reflect the revision status of the referenced requirement document (Background: \"AD revised to reflect requirement document revision status\") and points to De Havilland SB No. 6/166 Rev. B (Document). The AD retains the same applicability (S/Nos. 1 to 170) and does not, in the text of the AD itself, add or remove inspection obligations beyond directing compliance with the service bulletin (Applicability; Compliance; Document)."},"complexity_factors":["Mandatory action is by reference to an external document (De Havilland SB No. 6/166 Rev. B) rather than set out in the AD text (Document; Compliance).","Applicability limited to specific serial-number range (S/Nos. 1 to 170) — operators must check serial numbers to determine applicability (Applicability).","AD is an amendment that updates reference/revision status, creating a dependency on confirming the correct revision of the service bulletin (Background; Document).","Lack of in-text detail (inspection steps, intervals, corrective actions) requires operators and maintainers to obtain and interpret the service bulletin (Compliance)."],"plain_english_summary":"This Airworthiness Directive requires owners/operators of De Havilland DHC‑6 (Twin Otter) aeroplanes S/N 1–170 to comply with the inspection procedures in De Havilland Service Bulletin No. 6/166, Revision B, for the wing strut jo‑bolt. Compliance is mandatory by reference, costs fall to operators, and the AD amendment simply updates the instrument to reflect the service bulletin’s revision status."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This amendment performs a housekeeping update only — revising the directive to cite the current revision of the manufacturer's service bulletin. The substantive safety requirement (inspect the wing strut Jo-Bolts) remains unchanged from the original AD/15."},"complexity_factors":["Extremely short document (under 150 words)","No defined terms section — all language is technical aviation standard","Single, unambiguous applicability criterion (serial numbers 1–170)","No conditional logic or nested exceptions","Single external reference to manufacturer service bulletin (SB 6/166 Rev. B)","Purpose is purely administrative: updating reference to match revised source document"],"plain_english_summary":"**What this is:** This is an **Airworthiness Directive (AD)** — a mandatory safety order issued by Australia's Civil Aviation Safety Authority (CASA). Think of it as a \"recall notice\" for aircraft, but legally binding.\n\n**What it does:** It requires owners and operators of specific **de Havilland DHC-6 Twin Otter aircraft** (serial numbers 1 to 170) to inspect the **wing strut Jo-Bolts** — critical fasteners that help hold the wing to the fuselage. A failure here could be catastrophic.\n\n**Who must comply:** Anyone operating these specific Twin Otter models in Australia. \"Compliance\" means following the inspection procedures in the referenced technical document (De Havilland Service Bulletin 6/166, Revision B).\n\n**Why it matters:** This amendment (\"Amdt 1\") simply updates the directive to match a revised version of the manufacturer's service bulletin. It ensures Australian operators are working from the latest, most accurate safety instructions. No new inspection is added — the paperwork is just brought up to date.\n\n**Key takeaway:** If you fly or maintain an early-model Twin Otter (serial 1–170), make sure your maintenance logs show compliance with the current version of this inspection requirement."}},"importantCases":[],"_links":{"self":"/api/acts/ad-dhc-6-15-amdt-1-wing-strut-jo-bolt-inspection","history":"/api/acts/ad-dhc-6-15-amdt-1-wing-strut-jo-bolt-inspection/history","analysis":"/api/acts/ad-dhc-6-15-amdt-1-wing-strut-jo-bolt-inspection/analysis","conflicts":"/api/acts/ad-dhc-6-15-amdt-1-wing-strut-jo-bolt-inspection/conflicts","importantCases":"/api/acts/ad-dhc-6-15-amdt-1-wing-strut-jo-bolt-inspection/important-cases","documents":"/api/acts/ad-dhc-6-15-amdt-1-wing-strut-jo-bolt-inspection/documents"}}