{"id":"F2006B07595","name":"AD/VW/4 Amdt 1 - Propeller Adaptor Shaft","slug":"ad-vw-4-amdt-1-propeller-adaptor-shaft","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":50258,"registerId":"commonwealth-F2006B07595-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/VW/4 Amdt 1 - Propeller Adaptor Shaft","content":"COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 \\- 106 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\n![](image.001.png)  \nVolkswagen Derivative Piston Engines\n\nAD/VW/4\n\nAmdt 1\n\n  \nPropeller Adaptor Shaft 12/89\n\nApplicability: All Revmaster engines fitted with a short propeller adaptor shaft.\n\nRequirement: Carry out a fluorescent magnetic particle inspection of the propeller adaptor shaft, paying particular attention to the area of the oil transfer hole and internal slot.\n\nNote: Short propeller adaptor shafts can be identified in situ, by comparison of the shaft diameter adjacent to the propeller attachment flange. A short shat has a larger diameter forward of the flange in comparison with the diameter aft of the flange.\n\nCompliance: At each removal of a short propeller adaptor shaft form the crankshaft.\n\nBackground: This Directive has been amended to reflect the release in 1986 of an improved propeller adaptor shaft. The improved shaft features variations form the original shaft in material, heat treatment and dimensions. In-service experience to date with the improved shaft has been satisfactory, Therefore, this Amendment has been issued to limit applicability to the original (short) shaft.","sortOrder":0}],"analysis":{"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":true,"description":"The Amendment narrows scope: after an improved propeller adaptor shaft was released (1986), applicability was limited to the original 'short' shaft (Background). Practically, fewer shafts are now covered, but affected operators must identify short shafts in situ and perform the required inspection at each removal from the crankshaft (Applicability; Note; Compliance)."},"complexity_factors":["Prescribed non‑routine inspection method: fluorescent magnetic particle inspection is a specific NDT technique that requires trained personnel and equipment (Requirement).","Targeted inspection zones: focuses on small features (oil transfer hole and internal slot), increasing attention to detail and potential inspection time (Requirement).","Identification in situ: operators must distinguish 'short' shafts by comparing diameters adjacent to the propeller flange, which adds an operational verification step before deciding applicability (Note; Applicability).","Recurring compliance trigger: inspection obligation is tied to each removal of a short shaft from the crankshaft, creating repeated compliance events rather than a one‑off action (Compliance).","Scope narrowing by amendment: the directive was amended after release of an improved shaft, forcing operators to determine shaft type and apply the requirement only to original short shafts (Background)."],"plain_english_summary":"This airworthiness directive requires a fluorescent magnetic particle inspection of short propeller adaptor shafts on all Revmaster engines, with special attention to the oil transfer hole and internal slot. It applies only to the original short shaft and must be done each time such a shaft is removed from the crankshaft. It affects aircraft owners/operators and maintenance personnel by imposing a recurring inspection obligation at shaft removal (Applicability; Requirement; Compliance)."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":true,"description":"The original directive likely applied to all propeller adaptor shafts. Amendment 1 deliberately narrows the scope to exclude the improved shaft design released in 1986, limiting applicability only to the original 'short' shafts. This represents a reduction in scope rather than expansion — the legislation has become more targeted and precise based on in-service experience with the improved design."},"complexity_factors":["Single, specific mechanical component targeted (propeller adaptor shaft)","Only one technical inspection method specified (fluorescent magnetic particle inspection)","Simple applicability test based on physical measurement (diameter comparison)","Clear compliance trigger (at each removal)","No cross-references to other legislation or regulations","No defined terms section","Single amendment with straightforward purpose (limiting scope to original shafts only)","Total length: approximately 200 words"],"plain_english_summary":"Owners and mechanics of Revmaster light-aircraft engines with the original short propeller adaptor shaft must perform fluorescent magnetic particle inspection for cracks whenever that shaft is removed, focusing on the oil transfer hole and internal slot.  \n\nThis targets only the older, crack-prone short shafts (identifiable by a larger diameter in front of the prop flange); the improved 1986 design is excluded. Failure to inspect risks in‑flight propeller separation."}},"importantCases":[],"_links":{"self":"/api/acts/ad-vw-4-amdt-1-propeller-adaptor-shaft","history":"/api/acts/ad-vw-4-amdt-1-propeller-adaptor-shaft/history","analysis":"/api/acts/ad-vw-4-amdt-1-propeller-adaptor-shaft/analysis","conflicts":"/api/acts/ad-vw-4-amdt-1-propeller-adaptor-shaft/conflicts","importantCases":"/api/acts/ad-vw-4-amdt-1-propeller-adaptor-shaft/important-cases","documents":"/api/acts/ad-vw-4-amdt-1-propeller-adaptor-shaft/documents"}}