{"id":"F2009L02258","name":"AD/CL-600/109 - Nose Landing Gear Selector Valve","slug":"ad-cl-600-109-nose-landing-gear-selector-valve","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":162104,"registerId":"commonwealth-F2009L02258-current","compilationNumber":null,"startDate":"2026-04-04","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-600/109 | Nose Landing Gear Selector Valve | 7/2009 |\n| ------------- | -------------------------------- | ------ |\n\n| Applicability: | Bombardier Inc. Model CL-600-2B19, Serial Numbers (S/N) 7003 and subsequent. |\n| -------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n| Requirement: | 1. Check the S/N and identification markings on both the nose landing gear (NLG) selector valve and NLG door selector valve that are installed on the aircraft:a. If either or both selector valve S/Ns is in the range 0001 through 2126, and there is no suffix “T” or marking “SB750006000-1” on the valve, proceed to Requirement 2 of this AD.b. If both selector valves are identified with one or more of the following S/Ns or identification markings, no further action is required. Compliance with this AD is complete:- S/N outside the range 0001 through 2126;- suffix \"T\";- marking “SB750006000-1”.2. For each NLG selector valve and NLG door selector valve installed on the aircraft, that has a S/N in the range 0001 through 2126 but is not identified with suffix “T” or marking “SB750006000-1”:Check the valve and replace, rework and/or identify the valve, as required, in accordance with the Accomplishment Instructions of Bombardier Service Bulletin 601R-32-104, dated 3 March 2009, or later revisions approved by the Chief, Continuing Airworthiness, Transport Canada.Note 1: Valves that have a Serial Number (S/N) with suffix “T” has been manufactured by Tactair Fluid Controls Inc. and do not require any corrective action.Note 2: Valves manufactured by Kaiser Fluid Technologies, P/N 750006000, with S/N 0001 through 2126 and ink stamp “SB750006000-1”, have already been checked and reworked as necessary and do not require any additional corrective action. |\n\n| | Note 3. The Illustrated Parts Catalogue (CSP A-006) gives instructions not to install a valve manufactured by Kaiser Fluid Technologies, P/N 750006000, with S/N 0001 through 2126, if marking “SB750006000-1” is not ink stamped on the valve.Note 4: Transport Canada AD CF-2009-19 dated 29 April 2009 refers. |\n| ----------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n| Compliance: | Within 1600 flight hours or within 18 months after the effective date of this AD, whichever comes first. |\n| | This Airworthiness Directive becomes effective on 2 July 2009. |\n| Background: | A specific batch of NLG and NLG door selector valves, part number (P/N) 601R75146-1 (Kaiser Fluid Technologies P/N 750006000), may have had their end caps incorrectly lock-wired and/or incorrectly torqued during assembly. This condition can lead to the end cap backing off, with consequent damage to a seal and internal leakage within the valve. Subsequently, if electrical power is transferred or removed from the aircraft before the NLG safety pin is installed, any pressure, including residual pressure, in the No. 3 hydraulic system can result in an uncommanded NLG retraction and/or uncommanded opening of the NLG doors. There have been six cases reported on CL600-2B19 aircraft, one of which resulted in the collapse of the NLG at the departure gate.This AD mandates a check of the NLG and NLG door selector valves installed on all aircraft in the Applicability section above. Depending on the results, replacement, rework and/or additional identification of the valves may be required. |\n\n![](image.001.png) \nJames Coyne \nDelegate of the Civil Aviation Safety Authority\n\n22 May 2009","sortOrder":0},{"sectionNumber":"AD/CL-600/109","sectionType":"part","heading":"AD/CL-600/109","content":"## AD/CL-600/109","sortOrder":1},{"sectionNumber":"Nose Landing Gear Selector Valve","sectionType":"part","heading":"Nose Landing Gear Selector Valve","content":"## Nose Landing Gear Selector Valve","sortOrder":2},{"sectionNumber":"7/2009","sectionType":"part","heading":"7/2009","content":"## 7/2009","sortOrder":3}],"analysis":{"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":3,"scope_assessment":{"changed":false,"description":"This AD maintains its original narrow scope — addressing a specific manufacturing defect in a specific batch of hydraulic valves for a specific aircraft model. The directive has not expanded beyond its original safety purpose."},"complexity_factors":["Short, single-purpose directive focused on one mechanical component","Clear binary decision tree (check serial numbers → action or no action)","Only 4 defined identification criteria (serial number ranges, suffix \"T\", marking \"SB750006000-1\")","Single cross-reference to manufacturer service bulletin (Bombardier SB 601R-32-104)","Straightforward compliance timeline (1600 flight hours or 18 months)","No nested exceptions or conditional sub-clauses beyond the initial serial number check"],"plain_english_summary":"This AD orders operators of Bombardier Challenger CL-600-2B19 (serials 7003+) to inspect two nose-gear hydraulic valves because some were assembled with improperly secured end caps that can leak. Leaks plus electrical power cycling before the safety pin is installed can cause sudden nose-gear retraction or door opening — incidents include a gear collapse at a gate.\n\nValves with certain serials/markings must be inspected and repaired or replaced per the manufacturer within 1,600 flight hours or 18 months."},"flash_summary":{"complexity_score":4,"scope_assessment":{"changed":false,"description":"Scope is aligned with the AD text: it targets CL-600-2B19 aircraft from S/N 7003 onward and a specific batch of selector valves (P/N 750006000, S/N 0001–2126) and requires inspection and corrective action. The AD mirrors Transport Canada AD CF-2009-19 and relies on Bombardier SB 601R-32-104; it does not expand beyond those parts, serial numbers or corrective measures."},"complexity_factors":["Technical specificity: serial-number range (0001–2126) and particular ink/suffix markings determine action (Requirement 1).","Multiple corrective paths: replace, rework and/or identify per manufacturer's Service Bulletin (Requirement 2).","Mandatory reference to Bombardier Service Bulletin 601R-32-104 and allowance for later revisions (Requirement 2).","Limited applicability by aircraft serial number (CL-600-2B19, S/N 7003+) and by parts batch/P/N (Background; Notes).","Fixed compliance window (1,600 flight hours or 18 months) creates scheduling and availability pressures (Compliance).","Safety-critical consequence (uncommanded NLG retraction/collapse) raises enforcement priority (Background).","Cross-references to Illustrated Parts Catalogue and Transport Canada AD increase procedural interdependence (Notes).","Potential operational disruption: aircraft downtime, parts sourcing and labour costs borne by operators (Compliance/Requirement 2).","Recordkeeping and identification checks at component level increase maintenance administrative burden (Requirement 1, Note 3)."],"plain_english_summary":"This AD requires operators of Bombardier CL-600-2B19 aeroplanes (S/N 7003+) to check nose landing gear (NLG) selector valves for specific serial numbers and markings and, if affected, to replace, rework or identify the valves following Bombardier Service Bulletin 601R-32-104. It aims to prevent uncommanded NLG retraction caused by incorrectly assembled valve end caps (Background). Operators must complete work within 1,600 flight hours or 18 months; operators pay for inspections, parts and downtime, while the regulator enforces compliance."}},"importantCases":[],"_links":{"self":"/api/acts/ad-cl-600-109-nose-landing-gear-selector-valve","history":"/api/acts/ad-cl-600-109-nose-landing-gear-selector-valve/history","analysis":"/api/acts/ad-cl-600-109-nose-landing-gear-selector-valve/analysis","conflicts":"/api/acts/ad-cl-600-109-nose-landing-gear-selector-valve/conflicts","importantCases":"/api/acts/ad-cl-600-109-nose-landing-gear-selector-valve/important-cases","documents":"/api/acts/ad-cl-600-109-nose-landing-gear-selector-valve/documents"}}