{"id":"F2006B09144","name":"AD/DHC-6/56 - Landing Gear - Nose Wheel Steering Cables - Inspection and Modification","slug":"ad-dhc-6-56-landing-gear-nose-wheel-steering-cables-inspection-and-modification","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":115706,"registerId":"commonwealth-F2006B09144-current","compilationNumber":null,"startDate":"2026-04-03","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/DHC-6/56 - Landing Gear - Nose Wheel Steering Cables - Inspection and Modification","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-6 (Twin Otter) Series Aeroplanes\n\n \n\n# AD/DHC-6/56 Landing Gear - Nose Wheel Steering\n\nCables - Inspection and Modification\n\nApplicability: All model not incorporating modification No. 6/1800.\n\n# 5/84\n\n \n\nRequirement: 1. Conduct visual inspection of the nose gear steering cables, where they are visible, for cleanliness, fraying, kinks, broken strands and for corrosion and security. Insect the pulleys for evidence of wear, chipping and security.\n\n \n\n2.    Remove the control column covers and conduct a visual inspection of the entire length of the steering cables for cleanliness, fraying, kinks, broken strands and for corrosion and security. Inspect the pulleys for evidence of wear, chipping and security.\n\n \n\n3.    Unserviceable cables or pulleys found during the inspections required by paragraphs 1 or 2 above, must be replaced with serviceable parts before further flight in accordance with service bulletin 6/453.\n\n \n\nNote: Canadian Airworthiness Directive CF-84-03 and De Havilland Canada Service Bulletin 6/453 refer.\n\n \n\nCompliance: Within 100 hours time in service after 31 May 1984 and thereafter at intervals not exceeding 200 hours time in service until the incorporation of modification No.\n\n6/1800.\n\n \n\nBackground: The manufacturer has introduced a modified more flexible cable to replace the original whose short service life and failure in service is reported. Prior to replacing this cable a periodic inspection to monitor its condition is required.\n\n \n","sortOrder":0}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a standard, narrow Airworthiness Directive targeting a specific mechanical defect in a specific aircraft type. The scope remains tightly focused on nose wheel steering cable safety as originally intended."},"complexity_factors":["Single, specific aircraft type (DHC-6 Twin Otter)","Clear applicability test (modification No. 6/1800)","Only 3 numbered requirements with straightforward inspection tasks","Single compliance deadline with simple recurring interval (100 hours initially, then 200 hours)","No defined terms section, no cross-references to other legislation beyond a service bulletin reference","Background explanation provided in plain language"],"plain_english_summary":"Operators of De Havilland DHC‑6 Twin Otters (unless fitted with factory modification No. 6/1800) must inspect and, if necessary, replace nose‑wheel steering cables and pulleys. Visual checks and deeper inspections (removing control‑column covers) are required, with any defective parts replaced before flight. First inspection is within 100 flight hours after 31 May 1984, then every 200 flight hours until the permanent modification is installed. This addresses premature cable failures that risk loss of ground steering."},"flash_summary_failed":{"failed":true,"reason":"Unauthenticated. Configure AI_GATEWAY_API_KEY or use a provider module. Learn more: https://ai-sdk.dev/unauthenticated-ai-gateway","source":"analysis-cron"},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The directive targets aircraft lacking modification 6/1800 and mandates interim inspections and replacement until that modification is fitted. This aligns with the stated intent to monitor and mitigate premature cable failure pending installation of the manufacturer’s improved cable; it does not broaden scope beyond that interim safety objective."},"complexity_factors":["Narrow technical scope: applies only to DHC‑6 models without modification 6/1800 (limited fleet subset).","Clear, binary actions: visual inspections, removal of covers, and replacement of unserviceable parts (low procedural ambiguity).","Explicit compliance timing: initial 100‑hour deadline then 200‑hour recurring interval (straightforward scheduling).","Dependence on external document: replacement must follow Service Bulletin 6/453 (requires access to and compliance with manufacturer guidance).","Maintenance access burden: requires removal of control‑column covers to inspect full cable length (practical labor and downtime cost).","No agency discretion in routine cases: directive prescribes inspections and replacement before further flight, leaving little administrative judgment."],"plain_english_summary":"This airworthiness directive requires operators of DHC‑6 (Twin Otter) aeroplanes that have not fitted modification No. 6/1800 to inspect nose‑wheel steering cables and pulleys (including under the control‑column covers) for fraying, kinks, broken strands, corrosion and security, and to replace any unserviceable parts per De Havilland Service Bulletin 6/453 before further flight. Initial compliance is within 100 hours after 31 May 1984, then every 200 hours until the modified, more flexible cable is installed. Operators pay for inspections and replacements; the measure is an interim safety step pending the modification."}},"importantCases":[],"_links":{"self":"/api/acts/ad-dhc-6-56-landing-gear-nose-wheel-steering-cables-inspection-and-modification","history":"/api/acts/ad-dhc-6-56-landing-gear-nose-wheel-steering-cables-inspection-and-modification/history","analysis":"/api/acts/ad-dhc-6-56-landing-gear-nose-wheel-steering-cables-inspection-and-modification/analysis","conflicts":"/api/acts/ad-dhc-6-56-landing-gear-nose-wheel-steering-cables-inspection-and-modification/conflicts","importantCases":"/api/acts/ad-dhc-6-56-landing-gear-nose-wheel-steering-cables-inspection-and-modification/important-cases","documents":"/api/acts/ad-dhc-6-56-landing-gear-nose-wheel-steering-cables-inspection-and-modification/documents"}}