{"id":"F2009L03044","name":"AD/ENST 28/6 - Pre-Certification Requirements - Modifications - CANCELLED","slug":"ad-enst-28-6-pre-certification-requirements-modifications-cancelled","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"repealed","isInForce":false,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":80634,"registerId":"commonwealth-F2009L03044-current","compilationNumber":null,"startDate":"2026-04-02","status":"Repealed","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"Enstrom F-28 Series Helicopters","sectionType":"division","heading":"Enstrom F-28 Series Helicopters","content":"### Enstrom F-28 Series Helicopters\n\n| AD/ENST 28/6 | Pre-Certification Requirements - Modifications | 9/2009 |\n| ------------ | ---------------------------------------------- | ------ |\n\n| Requirement: | CANCELLED.                                                                                                                                                                                                                    |\n| ------------ | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n|              | This AD is cancelled on 27 August 2009.                                                                                                                                                                                       |\n| Background:  | This AD, raised in 1975, required a range of modifications to make the helicopter comply with the now cancelled ANO 101.24. Compliance was required before31 March 1975.Accordingly, this directive is no longer appropriate. |\n\n![](image.001.png)\n\nDavid Villiers  \nDelegate of the Civil Aviation Safety Authority\n\n30 June 2009","sortOrder":0},{"sectionNumber":"AD/ENST 28/6","sectionType":"part","heading":"AD/ENST 28/6","content":"## AD/ENST 28/6","sortOrder":1},{"sectionNumber":"Pre-Certification Requirements - Modific","sectionType":"part","heading":"Pre-Certification Requirements - Modifications","content":"## Pre-Certification Requirements - Modifications","sortOrder":2},{"sectionNumber":"9/2009","sectionType":"part","heading":"9/2009","content":"## 9/2009","sortOrder":3}],"analysis":{"kimi_summary":{"_metrics":{"model":"kimi-k2.5","source":"moonshot-batch","completionTokens":2045},"content_quality":"ok","complexity_score":1,"scope_assessment":{"changed":false,"description":"The instrument performs exactly as advertised—it cancels an obsolete 1975 directive. There is no scope expansion; it is purely a housekeeping measure to remove a defunct requirement that related to a cancelled regulation (ANO 101.24)."},"complexity_factors":["Single operative provision (cancellation)","No defined terms or interpretation section","No conditional logic, exceptions, or procedural steps","Extremely short (approximately 100 words of substantive content)","No cross-references to active legislation beyond identifying the cancelled AD"],"plain_english_summary":"This document officially scraps an outdated aviation safety rule for Enstrom F-28 helicopters.\n\n**What it does**\n* **Cancels Airworthiness Directive (AD) ENST 28/6** — a safety instruction first issued in 1975\n* **Takes effect on 27 August 2009**\n\n**Why it exists**\nThe original 1975 rule required specific modifications to these helicopters to meet an old safety standard (called ANO 101.24). That standard no longer exists, and the deadline to make the changes was 31 March 1975 — over 30 years ago. Because the rule is obsolete and serves no current safety purpose, the Civil Aviation Safety Authority (CASA) is formally removing it.\n\n**Who it affects**\nOwners and operators of Enstrom F-28 series helicopters. In practice, this simply cleans up the rulebooks by removing a defunct requirement that was already impossible to comply with (or was complied with decades ago)."}},"importantCases":[],"_links":{"self":"/api/acts/ad-enst-28-6-pre-certification-requirements-modifications-cancelled","history":"/api/acts/ad-enst-28-6-pre-certification-requirements-modifications-cancelled/history","analysis":"/api/acts/ad-enst-28-6-pre-certification-requirements-modifications-cancelled/analysis","conflicts":"/api/acts/ad-enst-28-6-pre-certification-requirements-modifications-cancelled/conflicts","importantCases":"/api/acts/ad-enst-28-6-pre-certification-requirements-modifications-cancelled/important-cases","documents":"/api/acts/ad-enst-28-6-pre-certification-requirements-modifications-cancelled/documents"}}