{"id":"F2006B06051","name":"AD/PAP/7 Amdt 1 - Replacement of Hub to Master Gear Mounting Bolts","slug":"ad-pap-7-amdt-1-replacement-of-hub-to-master-gear-mounting-bolts","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":114449,"registerId":"commonwealth-F2006B06051-current","compilationNumber":null,"startDate":"2026-04-03","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/PAP/7 Amdt 1 - Replacement of Hub to Master Gear Mounting Bolts","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 - 107 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\n \n\n![](image.001.png)  Propellers - Variable Pitch - Allison/Aeroproducts\n\n \n\nAD/PAP/7\n\nAmdt 1\n\n\nReplacement of Hub to Master Gear Mounting Bolts\n\n\n9/67\n\n \n\nApplicability: All model A6441 FN-606 and A6441 FN-606A. Document:  1. Allison CPB 63-317; or\n\n2. Allison CSL 189; or 3. FAA AD 67-20-1.\n\nCompliance: Before 1 November 1967.\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":{"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a discrete, single-issue safety directive focused specifically on bolt replacement for two propeller models. It has not expanded beyond its original narrow technical purpose. The amendment (Amdt 1) appears to be a routine update rather than a scope expansion."},"complexity_factors":["Extremely short document — only 8 substantive lines","No defined terms section","No cross-references to other legislation (only references to technical service documents)","Simple binary applicability test (two specific model numbers)","Single, unambiguous compliance action (replace bolts) with absolute deadline","No conditional logic, exceptions, or nested provisions","Straightforward incorporation by reference of three alternative technical standards"],"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). ADs are legally binding instructions that aircraft owners and operators must follow to fix unsafe conditions in aircraft, engines, or parts.\n\n**What it requires:** This directive orders the **replacement of specific bolts** that attach the propeller hub to the master gear on certain Allison/Aeroproducts variable-pitch propellers.\n\n**Who it affects:** Anyone operating aircraft with these specific propeller models:\n- **A6441 FN-606**\n- **A6441 FN-606A**\n\n**Why it matters:** Faulty or worn mounting bolts could cause the propeller hub to separate from the master gear — a catastrophic failure that could lead to loss of propeller control or the propeller detaching in flight. This AD mandates a fix before a specific deadline to prevent accidents.\n\n**Key details:**\n- **Deadline:** Must be completed before **1 November 1967**\n- **Technical references:** You can follow any of three approved documents to do the work:\n  1. Allison Service Bulletin CPB 63-317\n  2. Allison Service Letter CSL 189\n  3. FAA Airworthiness Directive 67-20-1 (the US equivalent)\n\n**Historical note:** This is Amendment 1 (Amdt 1) of the original AD, and the \"9/67\" indicates it was issued in September 1967. This is a **historical directive** — it applies to vintage aircraft and is no longer relevant to modern commercial aviation, though it remains on the books for any remaining aircraft of this type still in service."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The instrument is labelled an amendment (Amdt 1) but, within the text provided, the applicability remains confined to the two listed propeller models and the directive continues to require replacement of the hub-to-master-gear mounting bolts by a specified date (Applicability; Compliance). The extract does not expand or narrow the class of affected aircraft beyond those models, nor does it introduce additional categories or exemptions in the shown text."},"complexity_factors":["Narrow technical scope limited to two specific propeller models (Applicability)","Mandatory action with a fixed historical deadline (Compliance) — simple timing requirement but retrospective","Reliance on external technical documents for procedure and specification (Document) which requires cross-referencing","Technical task requiring specialised maintenance skills and parts (implied by subject matter)","No enforcement, penalty, or follow-up inspection details shown in the extract (creates ambiguity about implementation oversight)"],"plain_english_summary":"This AD mandates replacement of the hub-to-master-gear mounting bolts on all A6441 FN-606 and A6441 FN-606A propellers, to be completed by 1 November 1967. It binds aircraft owners/operators to follow the detailed procedures and parts specifications in Allison CPB 63-317, Allison CSL 189 and FAA AD 67-20-1. Compliance cost, scheduling and choice of maintenance provider rest with the owner/operator; failure to comply leaves the aircraft non‑conforming."}},"importantCases":[],"_links":{"self":"/api/acts/ad-pap-7-amdt-1-replacement-of-hub-to-master-gear-mounting-bolts","history":"/api/acts/ad-pap-7-amdt-1-replacement-of-hub-to-master-gear-mounting-bolts/history","analysis":"/api/acts/ad-pap-7-amdt-1-replacement-of-hub-to-master-gear-mounting-bolts/analysis","conflicts":"/api/acts/ad-pap-7-amdt-1-replacement-of-hub-to-master-gear-mounting-bolts/conflicts","importantCases":"/api/acts/ad-pap-7-amdt-1-replacement-of-hub-to-master-gear-mounting-bolts/important-cases","documents":"/api/acts/ad-pap-7-amdt-1-replacement-of-hub-to-master-gear-mounting-bolts/documents"}}