{"id":"F2006B08884","name":"AD/DH 104/6 Amdt 1 - Engine Mount Attachment Brackets - Inspection","slug":"ad-dh-104-6-amdt-1-engine-mount-attachment-brackets-inspection","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":52362,"registerId":"commonwealth-F2006B08884-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/DH 104/6 Amdt 1 - Engine Mount Attachment Brackets - 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)  DH 104 (Dove) Series Aeroplanes\n\n \n\nAD/DH 104/6\n\nAmdt 1\n\n\nEngine Mount Attachment Brackets - Inspection 3/75\n\n \n\nApplicability: All models not modified in accordance with TNS CT (104) Nos. 50 and 65. Document:               Hawker Siddeley TNS CT(104) Nos. 50 Issue 3 and 65 Issue 4.\n\nCompliance: At intervals not exceeding 50 hours time in service after 30 April 1973.\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":3,"scope_assessment":{"changed":false,"description":"The provided text does not state that the AD changes scope from an earlier instrument. It applies to all DH 104 models not modified in accordance with the specified TNS CT(104) documents and mandates inspections at intervals not exceeding 50 hours TIS after 30 April 1973. No information in the text indicates a change of scope from the original intent."},"complexity_factors":["Short, focused directive limited to a single inspection requirement (Title; Compliance).","Relies on external technical documents (Hawker Siddeley TNS CT(104) Nos. 50 Issue 3 and 65 Issue 4) for procedural detail, so implementers must consult those documents to comply (Document).","Contains an explicit exemption for aircraft already modified per the referenced TNS CT documents, requiring operators to verify modification status (Applicability).","Sets a frequent, time-based recurring compliance obligation (every 50 hours time-in-service), which creates operational scheduling considerations (Compliance).","Dated compliance reference (starts after 30 April 1973) — historical date may affect record-keeping and retrospective compliance checks (Compliance)."],"plain_english_summary":"This AD mandates recurring inspections of engine‑mount attachment brackets on DH 104 (Dove) aeroplanes not modified per Hawker Siddeley TNS CT(104) Nos. 50 & 65, using those technical notes for the inspection procedure. Inspections are required at intervals not exceeding 50 hours time‑in‑service from 30 April 1973.\n\nOwners/operators must carry the inspection costs and manage the recurring maintenance; aircraft already modified per the specified TNS documents are exempt."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a standard Airworthiness Directive with a narrow, specific safety purpose — inspecting engine mount brackets on a particular aircraft type. It has not expanded beyond its original technical safety intent."},"complexity_factors":["Very short document (approximately 150 words of substantive content)","Only 2 defined/referenced technical documents (TNS CT(104) Nos. 50 and 65)","Single compliance requirement with clear time interval (50 hours)","Simple applicability test (all models except those with specific modifications)","No nested exceptions, conditional logic, or cross-references to other legislation","Straightforward effective date (30 April 1973)"],"plain_english_summary":"This is an **Airworthiness Directive (AD)** — essentially a mandatory safety notice issued by Australia's Civil Aviation Safety Authority (CASA) for aircraft.\n\n**What it does:**\nOrders owners and operators of **DH 104 (Dove) series aeroplanes** to inspect the **engine mount attachment brackets** — the metal parts that hold the engine onto the wing or fuselage.\n\n**Who it affects:**\n- Owners and operators of all DH 104 Dove aircraft **unless** they have already been modified according to specific technical notices (TNS CT (104) Nos. 50 and 65).\n\n**What must be done:**\n- Inspect these brackets **every 50 hours of flight time** (\"time in service\").\n- This requirement started from **30 April 1973**.\n\n**Why it matters:**\nEngine mount brackets are critical safety components. If they crack or fail, the engine could detach from the aircraft in flight. This AD ensures regular checks to catch problems before they become catastrophic.\n\n**Key documents referenced:**\n- Hawker Siddeley technical notices TNS CT(104) No. 50 Issue 3 and No. 65 Issue 4 — these describe the proper inspection or modification procedures."}},"importantCases":[],"_links":{"self":"/api/acts/ad-dh-104-6-amdt-1-engine-mount-attachment-brackets-inspection","history":"/api/acts/ad-dh-104-6-amdt-1-engine-mount-attachment-brackets-inspection/history","analysis":"/api/acts/ad-dh-104-6-amdt-1-engine-mount-attachment-brackets-inspection/analysis","conflicts":"/api/acts/ad-dh-104-6-amdt-1-engine-mount-attachment-brackets-inspection/conflicts","importantCases":"/api/acts/ad-dh-104-6-amdt-1-engine-mount-attachment-brackets-inspection/important-cases","documents":"/api/acts/ad-dh-104-6-amdt-1-engine-mount-attachment-brackets-inspection/documents"}}