{"id":"F2007L03981","name":"AD/DHC-8/132 - Utility and Observer Lights","slug":"ad-dhc-8-132-utility-and-observer-lights","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":70715,"registerId":"commonwealth-F2007L03981-current","compilationNumber":null,"startDate":"2026-04-02","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-8/132 | Utility and Observer Lights | 11/2007 |\n| ------------ | --------------------------- | ------- |\n\n| Applicability: | DHC-8 Aircraft Models 102, 103, 106, 201, 202, 301, 311, 314 and 315, Serial Numbers 003 through 639 and Models 400, 401 and 402, Serial Numbers 4003, 4004, 4006 and 4008 through 4149.                                                                                                                                                                                                                                                                                                                                     |\n| -------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n| Requirement:   | 1. DHC-8 Aircraft Models 102, 103, 106, 201, 202, 301, 311, 314 and 315 - Install Modsum 8Q101603 to replace the affected carbon moulded resistive element potentiometers with wire-wound type potentiometers, for both the pilot and co-pilot utility lights. Bombardier Service Bulletin (SB) 8-33-53, original issue dated 1 December 2006, Revision A dated 14 March 2007, or later revisions approved by the Chief, Continuing Airworthiness, Transport Canada, provide instructions for incorporating Modsum 8Q101603. |\n|                | 2. DHC-8 Aircraft Models 400, 401 and 402 - Install Modsum 4-126381 to replace the affected carbon moulded resistive element potentiometers with wire-wound type potentiometers, for the pilot, co pilot and observer utility lights. Bombardier SB 84-33-10, original issue dated 1 December 2006, Revision A dated 14 March 2007, or later revisions approved by the Chief, Continuing Airworthiness, Transport Canada, provide instructions for incorporating Modsum 4-126381.                                            |\n|                | Note: Transport Canada AD CF-2007-11 refers.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 |\n| Compliance:    | Within 18 months after the effective date of this Directive.                                                                                                                                                                                                                                                                                                                                                                                                                                                                 |\n|                | This Airworthiness Directive becomes effective on 25 October 2007.                                                                                                                                                                                                                                                                                                                                                                                                                                                           |\n\n| Background: | Transport Canada has advised that several cases have been reported where the pilot, co-pilot or observer utility light system has failed, resulting in a burning smell within the cockpit. An investigation has revealed that, due to the orientation and location of the carbon moulded potentiometers used to control the intensity of the light, the potentiometers can fail and overheat in such a way that burning of the ceiling panel and the associated insulation blanket could occur. This could lead to the presence of smoke in the cockpit, requiring that the pilots carry out the appropriate emergency procedure. |\n| ----------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n\n![](image.001.png)  \nCharles Lenarcic  \nDelegate of the Civil Aviation Safety Authority\n\n10 September 2007","sortOrder":0},{"sectionNumber":"AD/DHC-8/132","sectionType":"part","heading":"AD/DHC-8/132","content":"## AD/DHC-8/132","sortOrder":1},{"sectionNumber":"Utility and Observer Lights","sectionType":"part","heading":"Utility and Observer Lights","content":"## Utility and Observer Lights","sortOrder":2},{"sectionNumber":"11/2007","sectionType":"part","heading":"11/2007","content":"## 11/2007","sortOrder":3}],"analysis":{"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The directive implements the corrective action described in the background: replacing carbon‑moulded potentiometers with wire‑wound types for the specified models/serial numbers. It does not broaden applicability beyond that list or add unrelated obligations; it prescribes the same Modsum/SB‑based installation route and an 18‑month compliance window."},"complexity_factors":["Narrow technical remedy: direct replacement of specific potentiometer type (electrical component swap)","Applicability limited to listed DHC‑8 models and serial-number ranges (requires accurate fleet identification)","Dependence on manufacturer service bulletins and Modsum procedures for installation instructions","Regulatory oversight: later SB revisions require approval by the Chief, Continuing Airworthiness, Transport Canada","Fixed compliance window (18 months) creates scheduling and downtime pressure for operators","Costs concentrated on affected owners/operators (parts, certified maintenance labour, potential grounding)","Safety consequence is immediate (overheating/possible cockpit smoke) but retrofit does not change airframe design broadly","Implementation requires skilled maintenance personnel and logistics for parts availability"],"plain_english_summary":"This directive requires operators of specified Bombardier DHC‑8 models/serial numbers to replace carbon-moulded resistive potentiometers that control pilot, co‑pilot and observer utility lights with wire‑wound potentiometers, following Bombardier service bulletins/Modsum instructions, within 18 months. The declared safety aim is to prevent potentiometer overheating that has produced burning smells and potential cockpit smoke. Owners/operators bear parts, labour and downtime costs; CASA/Transport Canada approval governs any later service‑bulletin revisions."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a standard Airworthiness Directive with a narrow, specific safety purpose — replacing defective cockpit light components. The scope remains tightly focused on the identified fire hazard and has not expanded beyond this original technical safety objective."},"complexity_factors":["Single, specific technical requirement with clear part numbers (Modsum 8Q101603 and 4-126381)","Straightforward applicability table dividing aircraft into two groups by model and serial number","Simple compliance deadline (18 months from effective date)","No nested exceptions, conditional clauses, or cross-references to other legislation beyond referencing the Canadian service bulletins","Clear, factual background explaining the safety risk without legal jargon","Total length is approximately one page with minimal defined terms"],"plain_english_summary":"CASA requires owners/operators of certain Bombardier DHC‑8 (Dash 8) aircraft to replace cockpit utility light dimmer switches because the carbon‑based originals can overheat, burn, and produce smoke. The AD covers specific Series 100/200/300 and Series 400 aircraft (particular serial numbers) and mandates replacing affected switches with safer wire‑wound versions.\n\nWork must be completed within 18 months of 25 October 2007 to eliminate the cockpit fire/smoke hazard."},"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-8-132-utility-and-observer-lights","history":"/api/acts/ad-dhc-8-132-utility-and-observer-lights/history","analysis":"/api/acts/ad-dhc-8-132-utility-and-observer-lights/analysis","conflicts":"/api/acts/ad-dhc-8-132-utility-and-observer-lights/conflicts","importantCases":"/api/acts/ad-dhc-8-132-utility-and-observer-lights/important-cases","documents":"/api/acts/ad-dhc-8-132-utility-and-observer-lights/documents"}}