{"id":"F2006B06312","name":"AD/PR/14 - Blade Retaining Bolt Locking Segment - Replacement","slug":"ad-pr-14-blade-retaining-bolt-locking-segment-replacement","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":47436,"registerId":"commonwealth-F2006B06312-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/PR/14 - Blade Retaining Bolt Locking Segment - Replacement","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 - Dowty Rotol\n\n \n\nAD/PR/14 Blade Retaining Bolt Locking NK Segment - Replacement\n\nApplicability: As detailed in the requirement document. Document: Dowty Rotol SB No. 61-714, Rev. 1.\n\nCompliance: Before installation in an aircraft following next overhaul completed after 1 January 1972.\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 text provided sets a single, specific replacement requirement and references Dowty Rotol SB No. 61-714, Rev. 1 for applicability and procedures. There is no indication within this document that the scope has been altered from an earlier version: the AD, as presented, imposes the replacement requirement for items identified in the referenced service bulletin and sets the compliance timing. Because the AD’s applicability is determined by the external service bulletin, any change in scope would appear in that bulletin rather than in the text shown here; the AD itself does not show a change of scope."},"complexity_factors":["Short, narrowly focused requirement (replacement of a single part) — reduces substantive complexity.","Applicability is defined by reference to an external document (Dowty Rotol SB No. 61-714, Rev. 1), creating a dependency and possible ambiguity for readers who do not have that bulletin.","Timing condition tied to overhauls completed after a historical date (1 January 1972) requires implementers to map overhaul records to the compliance trigger.","Lack of in-text technical rationale or procedural detail increases reliance on the service bulletin and on maintainers' interpretation.","Enforcement and recordkeeping details are not specified in the text, leaving administrative practice to regulator/industry norms."],"plain_english_summary":"This airworthiness directive requires replacement of the propeller blade retaining bolt locking NK segment on affected Dowty Rotol variable‑pitch propellers, carried out per Dowty Rotol Service Bulletin No. 61‑714, Rev. 1, before any affected propeller is installed following an overhaul completed after 1 January 1972. It binds aircraft owners/operators and maintenance/overhaul organisations, who must obtain parts, perform the work and keep records; the AD relies on the manufacturer’s bulletin for technical detail."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a discrete, single-issue airworthiness directive from 1972 addressing a specific mechanical defect in a specific propeller model. It has not expanded beyond its original narrow safety purpose."},"complexity_factors":["Extremely short document (under 150 words)","Only 2 operative requirements: applicability reference and compliance deadline","No defined terms section — relies entirely on external document (Dowty Rotol SB 61-714)","Single, unambiguous compliance trigger (overhaul after fixed date)","No cross-references to other legislation or regulations beyond the enabling CAR 1998 Part 39","No conditional logic, exceptions, or alternative compliance methods stated"],"plain_english_summary":"This is an **Airworthiness Directive (AD)** issued by Australia's Civil Aviation Safety Authority (CASA). It mandates a safety fix for specific aircraft propellers made by Dowty Rotol.\n\n**What it does:**\n- Requires replacement of a small part called the \"blade retaining bolt locking segment\" on certain variable-pitch propellers\n- This part prevents the bolts holding the propeller blades from coming loose during flight\n\n**Who it affects:**\n- Owners and operators of aircraft with Dowty Rotol variable-pitch propellers (specific models detailed in the referenced service bulletin)\n- Maintenance organisations that overhaul these propellers\n\n**What must be done:**\n- The locking segment must be replaced **before** the propeller is installed on an aircraft\n- This must happen during the **first overhaul completed after 1 January 1972**\n\n**Why it matters:**\n- Faulty or worn locking segments could allow propeller blades to detach in flight\n- This is a mandatory safety requirement — compliance is not optional\n- The directive references a manufacturer service bulletin (SB 61-714 Rev. 1) for technical details"}},"importantCases":[],"_links":{"self":"/api/acts/ad-pr-14-blade-retaining-bolt-locking-segment-replacement","history":"/api/acts/ad-pr-14-blade-retaining-bolt-locking-segment-replacement/history","analysis":"/api/acts/ad-pr-14-blade-retaining-bolt-locking-segment-replacement/analysis","conflicts":"/api/acts/ad-pr-14-blade-retaining-bolt-locking-segment-replacement/conflicts","importantCases":"/api/acts/ad-pr-14-blade-retaining-bolt-locking-segment-replacement/important-cases","documents":"/api/acts/ad-pr-14-blade-retaining-bolt-locking-segment-replacement/documents"}}