{"id":"F2006L01690","name":"AD/DHC-8/121 - Landing Gear Alternate Release Handles","slug":"ad-dhc-8-121-landing-gear-alternate-release-handles","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":59446,"registerId":"commonwealth-F2006L01690-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-8/121 | Landing Gear Alternate Release Handles | 7/2006 |\n| ------------ | -------------------------------------- | ------ |\n\n| Applicability: | Bombardier Inc. DHC-8 Models 102, 103, 106, 201, 202, 301, 311, 314 and 315, Serial Numbers 003 through 579.                                                                                                                                                                                                                                                                                                                                                                                                          |\n| -------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n| Requirement:   | Rework the main and nose landing gear release handles by incorporating Modsum 8Q100730.Bombardier Service Bulletin 8-32-146, Revision D, dated 7 February 2003, or later Transport Canada approved revisions provides instructions for incorporating Modsum 8Q100730.Prior incorporation of Modsum 8Q100730 in accordance with the original issue, Revision A, B or C, of Bombardier Service Bulletin 8-32-146 meets the requirements of this directive.Note: Transport Canada AD CF-2006-09 dated 8 May 2006 refers. |\n| Compliance:    | Within 3000 flight hours after the effective date of this AD.                                                                                                                                                                                                                                                                                                                                                                                                                                                         |\n|                | This Airworthiness Directive becomes effective on 6 July 2006.                                                                                                                                                                                                                                                                                                                                                                                                                                                        |\n| Background:    | Several cases have been reported of broken or damaged main and nose landing gear alternate release cables caused by rubbing and fraying at the cable to handle interface. In the event of an unsuccessful normal landing gear extension, breakage of either the main or nose landing gear alternate release cable could result in the inability to extend the main or nose landing gear.                                                                                                                              |\n\n![](image.001.png)  \nJames Coyne  \nDelegate of the Civil Aviation Safety Authority\n\n24 May 2006","sortOrder":0},{"sectionNumber":"AD/DHC-8/121","sectionType":"part","heading":"AD/DHC-8/121","content":"## AD/DHC-8/121","sortOrder":1},{"sectionNumber":"Landing Gear Alternate Release Handles","sectionType":"part","heading":"Landing Gear Alternate Release Handles","content":"## Landing Gear Alternate Release Handles","sortOrder":2},{"sectionNumber":"7/2006","sectionType":"part","heading":"7/2006","content":"## 7/2006","sortOrder":3}],"analysis":{"flash_summary":{"complexity_score":2,"scope_assessment":{"changed":false,"description":"The directive does not expand scope beyond its stated fleet and modification: it mandates incorporation of Modsum 8Q100730 for the listed DHC‑8 models/serial numbers and accepts prior compliance via SB revisions A–C (Applicability; Requirement). The AD therefore maintains the original corrective focus on preventing cable rubbing/fraying (Background) rather than altering fleet coverage."},"complexity_factors":["Narrow technical mandate: single modification to landing‑gear alternate release handles (Requirement: incorporate Modsum 8Q100730 via Bombardier Service Bulletin 8‑32‑146).","Clear applicability: limited to specified DHC‑8 models and serial numbers 003–579 (Applicability).","Compliance deadline: work due within 3,000 flight hours from the AD effective date (Compliance).","Permitted prior compliance: earlier incorporations using original issue or Revisions A–C of the SB meet the AD (Requirement), requiring operators to verify historical maintenance records.","Regulatory cross‑reference: the AD notes Transport Canada AD CF‑2006‑09 (Requirement/Note), creating potential coordination or recordkeeping considerations.","Low discretion: the AD prescribes a specific modsum and SB, leaving limited technical discretion to operators/maintenance organisations."],"plain_english_summary":"This Airworthiness Directive requires operators of Bombardier DHC‑8 Series aeroplanes (Models 102, 103, 106, 201, 202, 301, 311, 314, 315; S/N 003–579) to modify the main and nose landing‑gear alternate‑release handles by incorporating Modsum 8Q100730 per Bombardier Service Bulletin 8‑32‑146. The work addresses cable rubbing and fraying that can prevent gear extension; it must be completed within 3,000 flight hours of 6 July 2006. Operators pay for and schedule the modification and must demonstrate compliance to the regulator."},"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 is a standard, targeted airworthiness directive addressing a specific safety defect in a defined aircraft fleet. The scope remains precisely limited to the landing gear alternate release handle modification for the specified DHC-8 models."},"complexity_factors":["Single, specific technical requirement with clear applicability criteria (9 aircraft models, specific serial number range)","One main compliance pathway with a straightforward exception (prior compliance under earlier revisions counts)","No nested conditional logic or extensive cross-referencing to other legislation","Contains only one defined technical term reference (Modsum 8Q100730) explained via manufacturer service bulletin","Short, self-contained document with clear deadline (3000 flight hours)","Minor complexity from technical aviation terminology and reference to Canadian regulatory counterpart (Transport Canada AD)"],"plain_english_summary":"This CASA Airworthiness Directive mandates modifying the alternate emergency landing-gear release handles (Modsum 8Q100730) on specified Bombardier DHC‑8 (Dash 8) models/serials because cable rubbing and fraying can break the emergency release and prevent gear extension. \n\nOwners/operators of affected aircraft must comply within 3,000 flight hours from 6 July 2006; installations done per Revisions A–C of SB 8‑32‑146 are already acceptable."}},"importantCases":[],"_links":{"self":"/api/acts/ad-dhc-8-121-landing-gear-alternate-release-handles","history":"/api/acts/ad-dhc-8-121-landing-gear-alternate-release-handles/history","analysis":"/api/acts/ad-dhc-8-121-landing-gear-alternate-release-handles/analysis","conflicts":"/api/acts/ad-dhc-8-121-landing-gear-alternate-release-handles/conflicts","importantCases":"/api/acts/ad-dhc-8-121-landing-gear-alternate-release-handles/important-cases","documents":"/api/acts/ad-dhc-8-121-landing-gear-alternate-release-handles/documents"}}