{"id":"F2009L00956","name":"AD/PA-42/2 - Nacelle Fuel Tank Check Valve - Installation - CANCELLED","slug":"ad-pa-42-2-nacelle-fuel-tank-check-valve-installation-cancelled","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"repealed","isInForce":false,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":78470,"registerId":"commonwealth-F2009L00956-current","compilationNumber":null,"startDate":"2026-04-02","status":"Repealed","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"Piper PA-42 (Cheyenne III) Series Aeropl","sectionType":"division","heading":"Piper PA-42 (Cheyenne III) Series Aeroplanes","content":"### Piper PA-42 (Cheyenne III) Series Aeroplanes\n\n| AD/PA-42/2 | Nacelle Fuel Tank Check Valve - Installation | 4/2009 |\n| ---------- | -------------------------------------------- | ------ |\n\n| Requirement: | CANCELLED.                                                                                                                                                                                                    |\n| ------------ | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n|              | This AD is cancelled on 9 April 2009.                                                                                                                                                                         |\n| Background:  | This unique Australian AD specified installation of check valves in the nacelle fuel tank in accordance with Piper SB No. 736 within 100 hours time in service after June 1983. The AD is no longer required. |\n\n![](image.001.png)\n\nJames Coyne  \nDelegate of the Civil Aviation Safety Authority\n\n18 February 2009","sortOrder":0},{"sectionNumber":"AD/PA-42/2","sectionType":"part","heading":"AD/PA-42/2","content":"## AD/PA-42/2","sortOrder":1},{"sectionNumber":"Nacelle Fuel Tank Check Valve - Installa","sectionType":"part","heading":"Nacelle Fuel Tank Check Valve - Installation","content":"## Nacelle Fuel Tank Check Valve - Installation","sortOrder":2},{"sectionNumber":"4/2009","sectionType":"part","heading":"4/2009","content":"## 4/2009","sortOrder":3}],"analysis":{"kimi_summary":{"_metrics":{"model":"kimi-k2.5","source":"moonshot-batch","completionTokens":1862},"content_quality":"ok","complexity_score":1,"scope_assessment":{"changed":false,"description":"The legislation has not expanded beyond its original purpose; rather, it has been terminated. This instrument simply cancels the original airworthiness directive, eliminating all compliance obligations rather than adding new requirements or extending coverage to new aircraft types."},"complexity_factors":["Single operative provision (cancellation only)","No defined terms requiring interpretation","No conditional logic or procedural steps","No cross-references to other legislative instruments","Extremely brief (under 100 words of substantive content)"],"plain_english_summary":"This document officially **cancels a previous aviation safety rule** that applied to owners of Piper PA-42 Cheyenne III aircraft.\n\n**What it used to require:**\nPreviously, the Civil Aviation Safety Authority (CASA) mandated that owners install special one-way valves (called *check valves*) in the nacelle fuel tanks (the fuel tanks housed in the streamlined engine coverings) within 100 flight hours after June 1983. This was to prevent fuel from flowing backward or draining improperly.\n\n**What changed:**\nAs of **9 April 2009**, this requirement is completely cancelled. Aircraft owners no longer need to install these valves to comply with this specific rule.\n\n**Why it matters:**\nIf you own or operate a Piper PA-42 Cheyenne III, this cancellation means one less regulatory requirement to track. However, you must still comply with other applicable airworthiness directives and the manufacturer’s latest guidance."}},"importantCases":[],"_links":{"self":"/api/acts/ad-pa-42-2-nacelle-fuel-tank-check-valve-installation-cancelled","history":"/api/acts/ad-pa-42-2-nacelle-fuel-tank-check-valve-installation-cancelled/history","analysis":"/api/acts/ad-pa-42-2-nacelle-fuel-tank-check-valve-installation-cancelled/analysis","conflicts":"/api/acts/ad-pa-42-2-nacelle-fuel-tank-check-valve-installation-cancelled/conflicts","importantCases":"/api/acts/ad-pa-42-2-nacelle-fuel-tank-check-valve-installation-cancelled/important-cases","documents":"/api/acts/ad-pa-42-2-nacelle-fuel-tank-check-valve-installation-cancelled/documents"}}