{"id":"F2008L00784","name":"AD/DHC-2/32 Amdt 1 - Magneto Cannon Plug","slug":"ad-dhc-2-32-amdt-1-magneto-cannon-plug","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":72860,"registerId":"commonwealth-F2008L00784-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"DHC-2 (Beaver) Series Aeroplanes","sectionType":"division","heading":"DHC-2 (Beaver) Series Aeroplanes","content":"### DHC-2 (Beaver) Series Aeroplanes\n\n| AD/DHC-2/32 Amdt 1 | Magneto Cannon Plug | 4/2008 |\n| ------------------ | ------------------- | ------ |\n\n| Applicability: | All Model DHC-2 aeroplanes powered by radial engines incorporating a firewall magneto connector plug as described in Viking Air Limited Service Bulletin (SB) V2/0001. |\n| -------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n| Requirement: | 1. If not previously accomplished in accordance with the original issue of this Directive, perform a visual inspection of the firewall ignition plug and receptacle for proper lock wiring and security in accordance with the Accomplishment Instructions of Bombardier Aerospace de Havilland Beaver Alert Service Bulletin A2/53, Revision ‘A’ dated 30 August 2001 or later revision approved by the Chief, Continuing Airworthiness, Transport Canada. |\n| | 2. Replace any damaged parts detected during the Requirement 1 inspection. |\n| | 3. If not previously accomplished in accordance with the original issue of this Directive, incorporate Maintenance Manual PSM 1-2-2 Temporary Revision TR2-24, dated 24 August 2001, into the periodic inspection of the aircraft approved maintenance schedule. Once incorporated, this inspection is considered a routine task subject to normal maintenance program development and escalation. |\n| | TR2-24 may be removed from the Maintenance Manual when it is superseded by a normal revision to the manual. |\n| | 4. Replace the firewall magneto connector in accordance with the accomplishment instructions of Viking Air Limited SB V2/0001 dated 27 June 2007, or later revisions approved by the Chief, Continuing Airworthiness, Transport Canada. |\n| | Note: Transport Canada AD CF-2001-36R1 refers. |\n| Compliance: | For Requirement 1 - Within 3 months or 110 hours time in service after the effective date of this Directive, whichever occurs first. |\n| | For Requirement 2 - Before further flight after the Requirement 1 inspection. |\n| | For Requirement 3 - Within 3 months after the effective date of this Directive. |\n\n| | For Requirement 4 - Before 1 August 2008. |\n| ----------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n| | This Amendment becomes effective on 10 April 2008. |\n| Background: | Transport Canada has advised that a complete loss of both ignition systems occurred on a DHC-3 Otter when the lock wire hole in the ignition connector plug on the firewall broke out, allowing the plug to vibrate loose. A maintenance safety feature grounds out both magneto systems through a spring-loaded safety pin incorporated into the Cannon plug. The DHC-2 System is similar in design. |\n| | The original issue of this Directive required a one time inspection of the ignition connector plug to detect any discrepancies and, if necessary, their rectification. The Directive also required amendment of the Maintenance Manual. |\n| | Subsequent to the issuance of AD CF-2001-36 (AD/DHC-2/32) a complete loss of both ignition systems occurred on a DHC-2 Beaver, resulting in engine failure and subsequent forced approach and landing. Investigation by the Canadian Transportation Safety Board determined the internal failure of the magneto firewall connector resulted in both magneto “P” leads shorting to ground. A maintenance “safety” feature through a spring-loaded safety pin incorporated in the firewall connector on many DHC-2 aircraft grounds out both magneto systems when the connector is disconnected. This connector type is readily identified, when disconnected by the existence of three internal pins on the firewall and magneto harness side, one of which is shorted directly to ground.These connectors are no longer in production.Since no effective Instructions for Continued Airworthiness exist to ensure the safety feature of these connectors will operate correctly when disconnected, or will ensure the internal integrity of the connector while in service, this Directive is amended to mandate replacement of connectors with a different design.Viking Air Limited has developed SB V2/0001 to provide for the installation of a replacement connector, similar in design to magneto systems in service today. This modification incorporates a “straight through” type connector, ensuring magneto circuit integrity should the connection open. |\n| | The original issue of this Directive became effective on 29 November 2001. |\n\n![](image.001.png) \nDavid Punshon \nDelegate of the Civil Aviation Safety Authority\n\n13 February 2008","sortOrder":0},{"sectionNumber":"AD/DHC-2/32 Amdt 1","sectionType":"part","heading":"AD/DHC-2/32 Amdt 1","content":"## AD/DHC-2/32 Amdt 1","sortOrder":1},{"sectionNumber":"Magneto Cannon Plug","sectionType":"part","heading":"Magneto Cannon Plug","content":"## Magneto Cannon Plug","sortOrder":2},{"sectionNumber":"4/2008","sectionType":"part","heading":"4/2008","content":"## 4/2008","sortOrder":3}],"analysis":{"flash_summary":{"complexity_score":4,"scope_assessment":{"changed":true,"description":"Yes. The original Directive required a one‑time inspection of the ignition connector and amendment of the Maintenance Manual. This amendment expands scope by mandating replacement of the firewall magneto connector with a different design (per Viking SB V2/0001) to eliminate the grounding‑when‑disconnected safety feature deemed unsafe; it therefore moves from inspection/administrative change to a compulsory modification with specific compliance deadlines (see 'Requirement' and 'Background')."},"complexity_factors":["Multiple, interlinked actions with different deadlines (visual inspection within 3 months/110 hours; replacement of damaged parts before further flight; maintenance manual amendment within 3 months; full connector replacement by 1 August 2008).","Cross-references to external service documents and approvals: Bombardier de Havilland Beaver Alert SB A2/53 Rev A (or later TC‑approved revision) and Viking Air SB V2/0001 (or later TC‑approved revision).","Technical identification requirement: operators must identify the specific Cannon-style firewall connector (three internal pins, one grounded) to determine applicability and the correct replacement.","Regulatory coordination: relies on Transport Canada approvals (Chief, Continuing Airworthiness) and references Transport Canada AD CF‑2001‑36R1, introducing multi-jurisdictional compliance checks.","Maintenance-practice change: temporary revision TR2‑24 must be incorporated into periodic inspections and later removed when superseded, creating record‑keeping and procedural updates.","Safety-critical timing: requirement to replace defective parts before further flight increases operational disruption and urgency for rectification."],"plain_english_summary":"This Directive requires owners/operators of DHC‑2 (Beaver) aeroplanes with the specified firewall magneto connector to inspect the firewall ignition plug for secure lock‑wiring, repair or replace any damaged parts, add a temporary inspection procedure to the maintenance manual, and replace the existing connector with a redesigned “straight‑through” connector by the set date. It responds to incidents where connector failure caused loss of both magnetos and imposes inspection, modification and replacement costs and scheduling obligations on operators."},"kimi_summary":{"content_quality":"ok","complexity_score":3,"scope_assessment":{"changed":false,"description":"This amendment remains tightly focused on its original purpose: addressing the specific safety defect in the DHC-2 Beaver's magneto firewall connector. The amendment expands the original directive (which only required inspection and manual updates) to mandate physical replacement of the connector, but this is a logical escalation based on new incident data rather than scope creep. The measure stays within the boundaries of addressing this single, well-defined airworthiness issue."},"complexity_factors":["Single, specific applicability (one aircraft model with specific engine/connector configuration)","Four clearly numbered requirements with straightforward compliance deadlines","References to external technical documents (Service Bulletins, Maintenance Manual revisions) but with specific dates/versions provided","No nested conditional logic or exceptions — requirements apply uniformly to all affected aircraft","Limited defined terms (only standard aviation terminology like 'time in service')","Background narrative explains the safety rationale in plain language"],"plain_english_summary":"This CASA Airworthiness Directive targets DHC-2 Beaver aircraft with the firewall “Cannon” magneto connector, which can fail internally and ground both ignition systems, causing complete engine loss. It requires operators to inspect and repair or replace faulty connectors, update maintenance procedures, and fit a safer straight‑through connector (deadline 1 August 2008). This is a critical safety mandate to prevent in‑flight engine failures."},"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-2-32-amdt-1-magneto-cannon-plug","history":"/api/acts/ad-dhc-2-32-amdt-1-magneto-cannon-plug/history","analysis":"/api/acts/ad-dhc-2-32-amdt-1-magneto-cannon-plug/analysis","conflicts":"/api/acts/ad-dhc-2-32-amdt-1-magneto-cannon-plug/conflicts","importantCases":"/api/acts/ad-dhc-2-32-amdt-1-magneto-cannon-plug/important-cases","documents":"/api/acts/ad-dhc-2-32-amdt-1-magneto-cannon-plug/documents"}}