{"id":"F2006L00438","name":"AD/DHC-8/112 - Forward Engine Mount Assembly","slug":"ad-dhc-8-112-forward-engine-mount-assembly","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":117121,"registerId":"commonwealth-F2006L00438-current","compilationNumber":null,"startDate":"2026-04-03","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"Bombardier (Boeing Canada/De Havilland) ","sectionType":"division","heading":"Bombardier (Boeing Canada/De Havilland) DHC-8 Series Aeroplanes","content":"### Bombardier (Boeing Canada/De Havilland) DHC-8 Series Aeroplanes\n\n| AD/DHC-8/112 | Forward Engine Mount Assembly | 3/2006 |\n| ------------ | ----------------------------- | ------ |\n\n| Applicability: | Model DHC-8-400, DHC-8-401, and DHC-8-402 aircraft, serial numbers 4005, 4006, 4008 through 4016, 4018 through 4051, and 4053.                                                                                                                                                                                                                                                                                                                              |\n| -------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n| Requirement:   | Action in accordance with Transport Canada AD CF-2002-07.Note: Bombardier Alert Service Bulletin A84-71-06 Revision A refers.                                                                                                                                                                                                                                                                                                                               |\n| Compliance:    | As specified in the Requirement document, with a revised effective date of16 March 2006.                                                                                                                                                                                                                                                                                                                                                                    |\n|                | This Airworthiness Directive becomes effective on 16 March 2006.                                                                                                                                                                                                                                                                                                                                                                                            |\n| Background:    | The manufacturer of the forward engine mount assembly has identified that a certain part number pre-production engine mount assembly had been installed as a production engine mount assembly. The pre-production engine mount assembly has a reduced fatigue life. Installation of a pre-production engine mount assembly may result in premature failure of the forward engine mount that would degrade the integrity of the engine/nacelle installation. |\n\n![](image.001.png)  \nDavid Villiers  \nDelegate of the Civil Aviation Safety Authority\n\n3 February 2006","sortOrder":0},{"sectionNumber":"AD/DHC-8/112","sectionType":"part","heading":"AD/DHC-8/112","content":"## AD/DHC-8/112","sortOrder":1},{"sectionNumber":"Forward Engine Mount Assembly","sectionType":"part","heading":"Forward Engine Mount Assembly","content":"## Forward Engine Mount Assembly","sortOrder":2},{"sectionNumber":"3/2006","sectionType":"part","heading":"3/2006","content":"## 3/2006","sortOrder":3}],"analysis":{"flash_summary":{"complexity_score":4,"scope_assessment":{"changed":false,"description":"The directive’s substantive scope—affected aircraft models/serial numbers and the required response—is unchanged; the instrument updates only the effective compliance date (Compliance: revised effective date of 16 March 2006)."},"complexity_factors":["Reliance on an external instrument: mandatory compliance is achieved by following Transport Canada AD CF-2002-07 rather than specifying actions in full here (Requirement).","Cross-reference to manufacturer service guidance: Bombardier Alert Service Bulletin A84-71-06 Revision A is noted, requiring operators to obtain and interpret that material (Requirement).","Narrow, serial-numbered applicability increases administrative work to identify affected aircraft (Applicability: specific serial numbers listed).","Safety-critical structural issue (reduced fatigue life of a forward engine mount) raises operational and maintenance urgency and potential need for parts replacement or inspection (Background).","Revised effective date imposes an immediate compliance timeline (Compliance: revised effective date of 16 March 2006).","Low regulatory discretion: directive language mandates action in accordance with the referenced AD, limiting operator flexibility (Requirement)."],"plain_english_summary":"This directive requires operators of specified DHC-8-400 series aircraft to carry out the actions set out in Transport Canada AD CF-2002-07 regarding the forward engine mount assembly. It follows the manufacturer’s finding that a pre‑production engine‑mount part with reduced fatigue life was fitted in production, creating a risk of premature mount failure and potential degradation of the engine/nacelle installation; compliance is mandatory from 16 March 2006."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This AD maintains its original narrow scope: addressing a specific manufacturing defect in specific aircraft serial numbers. It has not expanded beyond its original safety purpose."},"complexity_factors":["Very short document (under 300 words)","Only 3 defined serial number ranges to identify affected aircraft","Single compliance action: follow an external document (Transport Canada AD)","No nested conditions, exceptions, or cross-references to other Australian legislation","Clear effective date with no alternative compliance methods or phased requirements"],"plain_english_summary":"This CASA Airworthiness Directive orders owners/operators of specified Bombardier DHC-8-400/-401/-402 aircraft (listed serial numbers) to inspect and replace inadvertently installed pre‑production forward engine mount assemblies per Transport Canada AD CF-2002-07 and Bombardier Alert Service Bulletin A84-71-06 Rev A by 16 March 2006. It’s mandatory because the prototype mounts can crack or fail prematurely, risking engine separation and catastrophic loss of control."},"flash_summary_failed":{"failed":true,"reason":"A positive credit balance is required for all requests, including BYOK, so fallback providers remain available. Add credits at https://vercel.com/d?to=%2F%5Bteam%5D%2F%7E%2Fai%3Fmodal%3Dtop-up to continue.","source":"analysis-cron"}},"importantCases":[],"_links":{"self":"/api/acts/ad-dhc-8-112-forward-engine-mount-assembly","history":"/api/acts/ad-dhc-8-112-forward-engine-mount-assembly/history","analysis":"/api/acts/ad-dhc-8-112-forward-engine-mount-assembly/analysis","conflicts":"/api/acts/ad-dhc-8-112-forward-engine-mount-assembly/conflicts","importantCases":"/api/acts/ad-dhc-8-112-forward-engine-mount-assembly/important-cases","documents":"/api/acts/ad-dhc-8-112-forward-engine-mount-assembly/documents"}}