{"id":"F2008L01926","name":"AD/CL-600/99 - Fuel Tank Climb Vent Loop","slug":"ad-cl-600-99-fuel-tank-climb-vent-loop","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":74153,"registerId":"commonwealth-F2008L01926-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"Bombardier (Canadair) CL-600 (Challenger","sectionType":"division","heading":"Bombardier (Canadair) CL-600 (Challenger) Series Aeroplanes","content":"### Bombardier (Canadair) CL-600 (Challenger) Series Aeroplanes\n\n| AD/CL-600/99 | Fuel Tank Climb Vent Loop | 7/2008 |\n| ------------ | ------------------------- | ------ |\n\n| Applicability: | Bombardier Inc. Model CL-600-2C10 aircraft, serial numbers 10003 through 10169 and CL-600-2D24 aircraft, serial numbers 15001 through 15025.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           |\n| -------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ |\n| Requirement:   | Modify the fuel tank climb vent loop pipes by installing shrouding boots according to the Accomplishment Instructions of Bombardier Service Bulletin (SB)670BA-28-011, Revision B, dated 4 July 2007, or later revisions approved by the Chief, Continuing Airworthiness, Transport Canada.Modification of climb vent pipe prior to the effective date of this directive according to the original issue or Revision A of the above-noted service bulletin satisfies the requirements of this directive.Note: Transport Canada AD CF-2008-01 dated 3 January 2008 refers.                                                                              |\n| Compliance:    | Within 4500 hours flight time after the effective date of this directive.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |\n|                | This Airworthiness Directive becomes effective on 3 July 2008.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |\n| Background:    | Bombardier Aerospace has completed a system safety review of theCL-600-2C10/CL-600-2D24 aircraft fuel system against new fuel tank safety standards, introduced in Chapter 525 of the Airworthiness Manual through Notice of Proposed Amendment (NPA) 2002-043. The identified non-compliances were assessed using Transport Canada Policy Letter No. 525-001 to determine if mandatory corrective action is required.This assessment showed that rupture of the fuel tank climb vent loop pipe or leakage from pipe couplings could result in fuel coming in contact with hot anti-ice ducts, creating potential fire on top of the centre fuel tank. |\n\n|     | To correct the unsafe condition, this directive mandates the modification of the fuel tank climb vent loop by installing shrouding boots that direct leaked fuel safely overboard. |\n| --- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n\n![](image.001.png)  \nJames Coyne  \nDelegate of the Civil Aviation Safety Authority\n\n22 May 2008","sortOrder":0},{"sectionNumber":"AD/CL-600/99","sectionType":"part","heading":"AD/CL-600/99","content":"## AD/CL-600/99","sortOrder":1},{"sectionNumber":"Fuel Tank Climb Vent Loop","sectionType":"part","heading":"Fuel Tank Climb Vent Loop","content":"## Fuel Tank Climb Vent Loop","sortOrder":2},{"sectionNumber":"7/2008","sectionType":"part","heading":"7/2008","content":"## 7/2008","sortOrder":3}],"analysis":{"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"No change from the instrument's stated original intent is evident in the text provided. The directive targets a specific unsafe condition and mandates the specified modification for identified serial-numbered aircraft, while accepting prior compliant modifications under earlier SB issues."},"complexity_factors":["Limited applicability to two CL-600 model variants and narrow serial-number ranges (Applicability).","Technical maintenance action: installation of shrouding boots on climb vent loop pipes (Requirement).","Dependence on a manufacturer service bulletin (SB670BA-28-011 Rev B) or later revisions approved by the Chief, Continuing Airworthiness, Transport Canada (Requirement).","Fixed compliance window: within 4,500 flight hours from the directive's effective date — requires operators to track hours and schedule work (Compliance).","Conditional acceptance of prior work: modifications done to the original issue or Rev A of the SB before the effective date satisfy the directive (Requirement).","Regulatory cross-references: links to Transport Canada AD CF-2008-01, Chapter 525 NPA 2002-043 and Policy Letter No. 525-001 increase procedural context for assessment and enforcement (Background)."],"plain_english_summary":"This directive requires installing shrouding boots on the fuel tank climb vent loop pipes of Bombardier CL-600-2C10 (S/N 10003–10169) and CL-600-2D24 (S/N 15001–15025) aircraft so leaked fuel is directed safely overboard. It affects operators of those aircraft, who must complete the modification per Bombardier Service Bulletin SB670BA-28-011 (Rev B or TC‑approved later revision) within 4,500 flight hours.\n\nThe stated purpose is to reduce the risk of fuel reaching hot anti-ice ducts and causing fire; Transport Canada accepts earlier compliance under the original issue or Rev A of the service bulletin."},"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"},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This AD maintains its original narrow scope: addressing a specific fuel tank fire risk identified through safety review. It applies only to the identified aircraft models and requires a single defined modification. No scope creep is evident."},"complexity_factors":["Single, specific technical requirement (install shrouding boots per defined service bulletin)","Limited applicability — only two specific aircraft models with defined serial number ranges","One clear compliance deadline (4,500 flight hours)","Minimal cross-referencing (only to Transport Canada AD and manufacturer service bulletin)","No nested exceptions or conditional logic — straightforward mandate with one grandfathering provision for prior modifications"],"plain_english_summary":"This CASA Airworthiness Directive requires owners/operators of specified Bombardier Challenger jets (CL-600-2C10 serials 10003–10169; CL-600-2D24 serials 15001–15025) to modify the fuel tank venting system by installing shrouding boots on climb vent loop pipes. \n\nThe change prevents fuel spray from a ruptured vent pipe or leaking coupling onto hot anti‑ice ducts—eliminating an in‑flight fire risk. Compliance is required within 4,500 flight hours after 3 July 2008; earlier SB revisions already done are acceptable."}},"importantCases":[],"_links":{"self":"/api/acts/ad-cl-600-99-fuel-tank-climb-vent-loop","history":"/api/acts/ad-cl-600-99-fuel-tank-climb-vent-loop/history","analysis":"/api/acts/ad-cl-600-99-fuel-tank-climb-vent-loop/analysis","conflicts":"/api/acts/ad-cl-600-99-fuel-tank-climb-vent-loop/conflicts","importantCases":"/api/acts/ad-cl-600-99-fuel-tank-climb-vent-loop/important-cases","documents":"/api/acts/ad-cl-600-99-fuel-tank-climb-vent-loop/documents"}}