{"id":"F2006B09732","name":"AD/F27/50 Amdt 1 - Nacelle Connections Sta 2574 - Modification","slug":"ad-f27-50-amdt-1-nacelle-connections-sta-2574-modification","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":115924,"registerId":"commonwealth-F2006B09732-current","compilationNumber":null,"startDate":"2026-04-03","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/F27/50 Amdt 1 - Nacelle Connections Sta 2574 - 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)  Fokker F27 Series Aeroplanes\n\n \n\nAD/F27/50\n\nAmdt 1\n\n\nNacelle Connections Sta 2574 - Modification 8/81\n\n \n\nApplicability:   All F27 aircraft.\n\n \n\nDocument: Fokker SB 61-9 (G-6) or 61-10 (G-7). Compliance:  Forthwith.\n\nBackground:  This Directive is raised in issue to call out the current manufacturers documents. Original SBJ-71 has been superseded by G-6 and G-7 is an alternative method of complying with G-6.\n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n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 routine amendment (Amendment 1) to an existing Airworthiness Directive. It simply updates the referenced technical documents to their current versions (G-6 and G-7) and adds G-7 as an alternative compliance method. The scope remains exactly as originally intended: ensuring the nacelle connection modification is performed on all F27 aircraft using current manufacturer instructions."},"complexity_factors":["Very short document (approximately 150 words of substantive content)","Only 2 defined document references (Fokker SB 61-9 and 61-10)","No nested conditional logic or exceptions","Single, unambiguous applicability clause ('All F27 aircraft')","Straightforward compliance requirement with no phased implementation or alternative compliance paths beyond the stated equivalent documents","Minimal cross-referencing (only to superseded document SBJ-71 for background context)"],"plain_english_summary":"This is an **Airworthiness Directive** (a mandatory safety order) issued by Australia's Civil Aviation Safety Authority for **Fokker F27 aircraft** — a type of regional turboprop aeroplane.\n\n**What it does:**\n- Requires owners and operators of all Fokker F27 planes to carry out a specific **modification** to the **nacelle connections** (the structural joints where the engine housing attaches to the wing) at **station 2574** (a specific measurement point along the aircraft structure).\n- The modification must be done according to **Fokker Service Bulletin 61-9 (version G-6)** or alternatively **Service Bulletin 61-10 (version G-7)**.\n\n**Who it affects:**\n- Anyone who owns, operates, or maintains a Fokker F27 aircraft in Australia.\n\n**Why it matters:**\n- This is a **safety-critical update**. The original service bulletin (SBJ-71) has been replaced by newer documents (G-6 and G-7). The directive ensures all F27s are modified using the current, correct instructions to maintain structural integrity of the engine mounting — failure of which could have catastrophic consequences.\n- **Compliance is immediate** (\"Forthwith\" means right away, without delay)."},"flash_summary":{"complexity_score":2,"scope_assessment":{"changed":false,"description":"The AD updates and clarifies the referenced manufacturer documentation by replacing the original SBJ-71 reference with Fokker SB 61-9 (G-6) and listing SB 61-10 (G-7) as an alternative method of compliance. It does not change the population of affected aircraft (the applicability remains 'All F27 aircraft') nor add new categories of aircraft. (Background; Applicability; Document.)"},"complexity_factors":["Single, narrowly defined technical requirement (nacelle connections at station 2574).","Clear applicability: 'All F27 aircraft'.","Compliance method is delegated to specific manufacturer service bulletins (SB 61-9 (G-6) or SB 61-10 (G-7)), reducing technical detail in the AD itself.","Immediate timing: 'Forthwith' requires prompt action but does not add procedural layers.","AD text omits operational details (cost allocation, approval processes, certifying authority), which simplifies the instrument but shifts complexity to implementation by operators and maintainers."],"plain_english_summary":"This AD requires every Fokker F27 to have the nacelle connections at station 2574 modified immediately, by following Fokker Service Bulletin 61-9 (G‑6) (or alternatively SB 61-10 (G‑7)). It updates a prior SB reference (superseding SBJ-71). The AD sets the method and timing but does not address who bears costs, who must perform the work, or approval paperwork."}},"importantCases":[],"_links":{"self":"/api/acts/ad-f27-50-amdt-1-nacelle-connections-sta-2574-modification","history":"/api/acts/ad-f27-50-amdt-1-nacelle-connections-sta-2574-modification/history","analysis":"/api/acts/ad-f27-50-amdt-1-nacelle-connections-sta-2574-modification/analysis","conflicts":"/api/acts/ad-f27-50-amdt-1-nacelle-connections-sta-2574-modification/conflicts","importantCases":"/api/acts/ad-f27-50-amdt-1-nacelle-connections-sta-2574-modification/important-cases","documents":"/api/acts/ad-f27-50-amdt-1-nacelle-connections-sta-2574-modification/documents"}}