{"id":"F2006B06327","name":"AD/PR/28 Amdt 1 - Hub Switches","slug":"ad-pr-28-amdt-1-hub-switches","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":47485,"registerId":"commonwealth-F2006B06327-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/PR/28 Amdt 1 - Hub Switches","content":"COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 \\- 107 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\n![](image.001.png)  \nPropellers \\- Variable Pitch \\- Dowty Rotol\n\nAD/PR/28\n\nAmdt 1\n\n  \nHub Switches 10/89\n\nApplicability: Any Dowty Rotol Propeller P/N R193/4-30-4/xxx with the following S/N installed on Fokker F-27 aircraft.\n\nDRG 225/63, \\- 265/64, \\- 23/68, \\- 121/70, \\- 59/76, \\- 21/77, \\- 65/77, \\- 76/77, \\- 8/78, \\- 44/78, - 120/78, - 121/78, - 15/79, - 417/80 - 1127/80 - 3954/86.\n\nDowty Rotol Propeller P/N R184/x-xx-x/xxx S/No DRG 118/65 installed on Gulfstream 1 G 159 aircraft.\n\nRequirement: Inspect hub switches for correct fitment, location and correct brush installation within the hub switch block. Refer Dowty Rotol Maintenance Manual 876 CM 61-2-4 Page 302/2.\n\nNote 1: Use switch P/N 601023026 in position 1 and 3 and switch P/N 601023027 in\n\nposition 2.\n\nNote 2: Netherlands AD 89-19 issue 2 refers.\n\nCompliance: Unless already accomplished at next inspection for issue of a Maintenance release or by 30 October 1989 whichever occurs first.\n\nBackground: Due to the possibility that the hub switches may have been incorrectly installed a one time inspection is required. Amendment 1 corrects a serial no. change.","sortOrder":0}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a narrow, technical airworthiness directive with a single purpose: mandating inspection of specific propeller hub switches. Amendment 1 makes a minor correction to serial numbers without expanding the scope beyond the original safety intent."},"complexity_factors":["Single, specific technical requirement (one-time inspection)","Limited applicability: only 15 specific propeller serial numbers on Fokker F-27s plus one serial number on Gulfstream aircraft","No defined terms section or interpretation provisions","No cross-references to other legislation (only references technical manual and related Dutch AD)","Simple compliance deadline structure (next inspection or fixed date)","Straightforward amendment purpose (serial number correction only)"],"plain_english_summary":"This CASA safety directive mandates a one‑time inspection of hub switches in specified Dowty Rotol propellers on Fokker F‑27 and one Gulfstream 1 G‑159 propeller to verify correct fitment, location and brush installation. Incorrect installations can cause propeller malfunction; compliance is required by the next maintenance check or 30 October 1989, whichever is earlier. Amendment 1 corrects a propeller serial number from the original 1989 directive."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":true,"description":"Amendment 1 corrects a serial number change; the instrument retains the same one‑time inspection requirement but updates the serial number listing (Background)."},"complexity_factors":["Narrow technical applicability: specific propeller P/Ns and a list of serial numbers restrict who is affected (Applicability).","Technical inspection standard referenced: requires use of Dowty Rotol Maintenance Manual 876 CM 61-2-4 p.302/2 (Requirement).","Explicit parts-placement requirement: specific switch P/Ns mandated for positions 1, 2 and 3 (Notes).","One-time compliance deadline tied to maintenance release or a calendar date (Compliance).","Cross-reference to an overseas airworthiness directive increases traceability and potential coordination (Note 2)."],"plain_english_summary":"Requires a one‑time inspection of hub switches on specific Dowty Rotol propellers installed on Fokker F‑27 and Gulfstream 1 aircraft. Inspectors must check correct fitment, location and brush installation per Dowty Rotol Maintenance Manual 876 CM 61‑2‑4 p.302/2 and use switch P/N 601023026 in positions 1 and 3 and P/N 601023027 in position 2 (Requirement; Notes).\n\nAircraft operators pay for the inspection and any corrective work; an approved maintenance organisation or qualified person decides and carries out the inspection. Compliance is due at next maintenance release or by 30 October 1989 (Compliance)."}},"importantCases":[],"_links":{"self":"/api/acts/ad-pr-28-amdt-1-hub-switches","history":"/api/acts/ad-pr-28-amdt-1-hub-switches/history","analysis":"/api/acts/ad-pr-28-amdt-1-hub-switches/analysis","conflicts":"/api/acts/ad-pr-28-amdt-1-hub-switches/conflicts","importantCases":"/api/acts/ad-pr-28-amdt-1-hub-switches/important-cases","documents":"/api/acts/ad-pr-28-amdt-1-hub-switches/documents"}}