{"id":"F2008L00161","name":"AD/CESSNA 337/6 - Control Systems - Modification - CANCELLED","slug":"ad-cessna-337-6-control-systems-modification-cancelled","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"repealed","isInForce":false,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":72324,"registerId":"commonwealth-F2008L00161-current","compilationNumber":null,"startDate":"2026-04-02","status":"Repealed","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"Cessna 337 Series Aeroplanes","sectionType":"division","heading":"Cessna 337 Series Aeroplanes","content":"### Cessna 337 Series Aeroplanes\n\n| AD/CESSNA 337/6 | Control Systems - Modification | 2/2008 |\n| --------------- | ------------------------------ | ------ |\n\n| Requirement: | CANCELLED.                                                                                                                                                                                                                                                                                                                |\n| ------------ | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n|              | This AD is cancelled on 14 February 2008.                                                                                                                                                                                                                                                                                 |\n| Background:  | This is a unique Australian AD issued in 1970 requiring a once off replacement of a number of NAS 679 lock nuts installed on Cessna aircraft between April and November in 1969. These nuts were suspected to have a manufacturing flaw. As all nuts would have now been replaced, the unsafe condition no longer exists. |\n\n![](image.001.png)\n\nCharles Lenarcic  \nDelegate of the Civil Aviation Safety Authority\n\n20 December 2007","sortOrder":0},{"sectionNumber":"AD/CESSNA 337/6","sectionType":"part","heading":"AD/CESSNA 337/6","content":"## AD/CESSNA 337/6","sortOrder":1},{"sectionNumber":"Control Systems - Modification","sectionType":"part","heading":"Control Systems - Modification","content":"## Control Systems - Modification","sortOrder":2},{"sectionNumber":"2/2008","sectionType":"part","heading":"2/2008","content":"## 2/2008","sortOrder":3}],"analysis":{"kimi_summary":{"_metrics":{"model":"kimi-k2.5","source":"moonshot-batch","completionTokens":1497},"content_quality":"ok","complexity_score":1,"scope_assessment":{"changed":false,"description":"This instrument performs exactly the function described—it terminates the previous Airworthiness Directive. There is no expansion of scope or mission creep; it simply removes a requirement that has become redundant over time."},"complexity_factors":["Single operative provision consisting of one word: 'CANCELLED'","No defined terms, interpretation section, or technical appendices","No cross-references to other legislative instruments beyond the historical background","Purely administrative nature with no conditions, exceptions, or procedural steps"],"plain_english_summary":"This document officially cancels a 1970 aviation safety rule that required owners of Cessna 337 Series aeroplanes to replace faulty lock nuts on their aircraft control systems.\n\n**What it does:**\n- **Cancels Airworthiness Directive AD/CESSNA 337/6** effective 14 February 2008.\n- **The original rule** required a one-time replacement of specific NAS 679 lock nuts (a type of securing fastener) installed on Cessna 337 aircraft between April and November 1969. These nuts had a suspected manufacturing flaw that could compromise flight safety.\n\n**Why it matters:**\n- After nearly 40 years, aviation authorities determined that all affected nuts would have been replaced during routine maintenance, meaning the unsafe condition no longer exists.\n- This removes an administrative compliance burden for aircraft owners and mechanics, who no longer need to track or prove compliance with a long-obsolete requirement."}},"importantCases":[],"_links":{"self":"/api/acts/ad-cessna-337-6-control-systems-modification-cancelled","history":"/api/acts/ad-cessna-337-6-control-systems-modification-cancelled/history","analysis":"/api/acts/ad-cessna-337-6-control-systems-modification-cancelled/analysis","conflicts":"/api/acts/ad-cessna-337-6-control-systems-modification-cancelled/conflicts","importantCases":"/api/acts/ad-cessna-337-6-control-systems-modification-cancelled/important-cases","documents":"/api/acts/ad-cessna-337-6-control-systems-modification-cancelled/documents"}}