{"id":"F2006B08922","name":"AD/DH114/12 Amdt 1 - Aileron Lever Part No. 14 WA. 199 - Inspection and Modification","slug":"ad-dh114-12-amdt-1-aileron-lever-part-no-14-wa-199-inspection-and-modification","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":52480,"registerId":"commonwealth-F2006B08922-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/DH114/12 Amdt 1 - Aileron Lever Part No. 14 WA. 199 - 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)  DH114 (Heron) Series Aeroplanes\n\n \n\nAD/DH114/12\n\nAmdt 1\n\n\nAileron Lever Part No. 14 WA. 199 - Inspection NK and Modification\n\n \n\nApplicability: All models not incorporating Mod. No. 662. Document: Hawker Siddeley TNS Heron (114) No. W.3, Issue 3.\n\nCompliance: Inspect at intervals not exceeding 50 hours time in service until modified. Modify before 1 June 1970.\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":true,"description":"This instrument is labelled as Amendment 1 to AD/DH114/12 (Amdt 1). As presented, it imposes a new inspection interval and a mandatory modification deadline for Aileron Lever Part No. 14 WA.199 on all Heron models that do not already have Mod. No. 662 (Applicability; Compliance). The amendment therefore changes the set of required actions for affected aircraft by adding or clarifying inspection and modification obligations and by setting an absolute completion date."},"complexity_factors":["Short, focused directive with a single technical requirement (low breadth).","Clear temporal obligations (inspection interval ≤50 hours; modification by 1 June 1970) (straightforward timing).","Applicability limited by presence/absence of Mod. No. 662, requiring record checks (procedural check).","Reference to an external technical document (Hawker Siddeley TNS Heron (114) No. W.3, Issue 3) for procedural details increases implementation dependency.","Use of undefined phrase \"Inspection NK\" within the directive creates ambiguity about inspection standard/method (increases complexity for compliance).","No alternative compliance routes or enforcement details in the text (practitioners must infer enforcement from broader regulatory framework).","Historical calendar deadline (1 June 1970) makes this directive clearly time‑bound but may complicate retrospective record checks."],"plain_english_summary":"# What this directive does\n\nThis airworthiness directive requires inspections and a modification for a specific aileron lever (Part No. 14 WA.199) on DH114 (Heron) series aeroplanes. It applies to every Heron model that has not already had Modification No. 662 fitted (Applicability). The directive sets two firm obligations: operators must inspect the part at intervals of no more than 50 hours time in service until the part is modified, and the modification must be completed before 1 June 1970 (Compliance). The directive refers to Hawker Siddeley TNS Heron (114) No. W.3, Issue 3 for the related documentation (Document).\n\n# Who this affects, who decides, and who pays\n\n- Who decides: The directive is issued under the Commonwealth Civil Aviation Regulations and appears in the Civil Aviation Safety Authority schedule of airworthiness directives (header). That is the regulatory source ordering the inspections and modification.  \n- Who it affects: Owners/operators of DH114 (Heron) series aeroplanes that do not incorporate Mod. No. 662 (Applicability).  \n- Who pays: Aircraft owners/operators are responsible for performing the inspections and paying for the modification (Compliance). Costs include labour, parts, aircraft downtime and any associated paperwork.\n\n# How it works mechanically\n\n- Applicability rule: The obligation attaches to every Heron model unless Modification No. 662 is already fitted (Applicability).  \n- Inspection requirement: Carry out inspections at intervals not exceeding 50 hours time in service until the required modification is installed (Compliance). The instruction text uses the phrase \"Inspection NK\"; that phrase appears here but is not defined in this document (header/Compliance).  \n- Modification requirement: Install the modification before 1 June 1970 (Compliance).  \n- Reference for procedures: The directive points to Hawker Siddeley TNS Heron (114) No. W.3, Issue 3 for the relevant technical documentation (Document). That external document is likely the source of the step‑by‑step inspection/modification procedure; this AD itself sets the mandatory timing and applicability.\n\n# Practical implementation, incentives and trade‑offs\n\n- Compliance burden and timing: Operators must allocate maintenance hours and parts stock or procurement to meet an inspection rhythm of every ≤50 hours of service until the modification is carried out (Compliance). They must also schedule and fund the modification prior to the stated deadline (Compliance).  \n- Administrative and operational cost: The owner/operator bears the direct monetary cost, plus indirect costs from aircraft downtime and scheduling impacts.  \n- Discretion and detail: The AD prescribes what must be done and when but provides little procedural detail within this text. The technical steps and acceptance criteria are left to the referenced Hawker Siddeley document (Document). That creates reliance on that external document for correct execution.  \n- Exclusions and substitution: Aircraft already incorporating Mod. No. 662 are excluded from these requirements (Applicability). There is no alternative compliance pathway shown in this text.  \n- Risk of ambiguity: The undefined term \"Inspection NK\" in the directive introduces potential ambiguity about the required inspection standard or method; implementers must consult the referenced technical document to resolve that (header/Document).\n\n# Net effect (mechanical, not normative)\n\nOperators of affected Herons must inspect the specified aileron lever frequently until they carry out a mandated modification by a fixed calendar date. The regulator imposes the timing and the deadline; operators pay the costs and must follow the referenced technical manual for how to perform the work (Applicability; Compliance; Document)."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is Amendment 1 to an existing Airworthiness Directive, but the scope remains tightly focused on the specific aileron lever inspection and modification requirement for DH114 Heron aircraft. There is no evidence of scope creep; it maintains its original safety purpose."},"complexity_factors":["Extremely short document (approximately 150 words)","Only 1 defined term implicitly referenced (Mod. No. 662)","No cross-references to other legislation or regulations beyond the parent Civil Aviation Regulations 1998","Simple conditional logic: applies to 'all models not incorporating Mod. No. 662'","Clear, unambiguous compliance requirements with specific timeframes","Single technical reference document (Hawker Siddeley TNS W.3)","No nested exceptions or sub-delegations"],"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 **DH114 Heron series aeroplanes** (a British-made twin-engine aircraft from the 1950s-60s) to:\n- **Inspect** a specific part — the aileron lever (part number 14 WA.199) — every 50 hours of flight time\n- **Modify** the aircraft by installing Modification No. 662 before 1 June 1970\n\n**Who it affects:** Anyone operating or maintaining DH114 Heron aircraft that haven't already been modified with Mod. No. 662.\n\n**Why it matters:** Ailerons control the aircraft's roll (banking left/right). A faulty lever could cause loss of control. The directive prevents accidents by catching wear or fatigue before failure occurs.\n\n**Key details:**\n- **Source document:** Hawker Siddeley Technical Note W.3, Issue 3\n- **Deadline:** Modification mandatory before 1 June 1970\n- **Until modified:** Inspect every 50 flight hours"}},"importantCases":[],"_links":{"self":"/api/acts/ad-dh114-12-amdt-1-aileron-lever-part-no-14-wa-199-inspection-and-modification","history":"/api/acts/ad-dh114-12-amdt-1-aileron-lever-part-no-14-wa-199-inspection-and-modification/history","analysis":"/api/acts/ad-dh114-12-amdt-1-aileron-lever-part-no-14-wa-199-inspection-and-modification/analysis","conflicts":"/api/acts/ad-dh114-12-amdt-1-aileron-lever-part-no-14-wa-199-inspection-and-modification/conflicts","importantCases":"/api/acts/ad-dh114-12-amdt-1-aileron-lever-part-no-14-wa-199-inspection-and-modification/important-cases","documents":"/api/acts/ad-dh114-12-amdt-1-aileron-lever-part-no-14-wa-199-inspection-and-modification/documents"}}