{"id":"F2007L03912","name":"AD/BELL 430/12 - Disc Assemblies - Tail Rotor Driveshaft","slug":"ad-bell-430-12-disc-assemblies-tail-rotor-driveshaft","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":70560,"registerId":"commonwealth-F2007L03912-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"Bell Helicopter Textron Canada (BHTC) 43","sectionType":"division","heading":"Bell Helicopter Textron Canada (BHTC) 430 Series Helicopters","content":"### Bell Helicopter Textron Canada (BHTC) 430 Series Helicopters\n\n| AD/BELL 430/12 | Disc Assemblies - Tail Rotor Driveshaft | 12/2007 DM |\n| -------------- | --------------------------------------- | ---------- |\n\n```html\n

Applicability:

Bell Helicopter Textron Canada (BHTC) Model 430 helicopters S/N up to 49120 fitted with disc assemblies part number (P/N) 36300-1, 37855-1 and C048354-1.

Requirement:

1. Verify disc assemblies P/N 36300-1, 37855-1 and C048354-1 for manufacturing date, proper thickness and indexing, in accordance with the instructions provided in BHTC Alert Service Bulletin (ASB) ASB-430-07-40 dated 28 March 2007 or later approved revisions.

If disc assemblies, after verification in accordance with Requirement 1, do not require any further action, or if the manufacturing date is not between 01 November 2005 and 30 November 2006, make an appropriate log book entry to this effect. No further action is required.

2. Remove any disc assembly which is not within the required thickness as per table below:

Disc Assembly P/N

Total Thickness

Minimum

Maximum

36300-1

0.174 inch (4.42 mm)

0.186 inch (4.75 mm)

37855-1

0.126 inch (3.20 mm)

0.138 inch (3.50 mm)

C048354-1

0.046 inch (1.16 mm)

0.051 inch (1.29 mm)

3. Remove any disc assembly which is not properly indexed.

4. Do not install any of the disc assemblies P/N 36300-1, 37855-1 and C048354-1 into any helicopter unless it is compliant to the ASB-430-07-40 dated 28 March 2007 or later approved revisions.

Note: Transport Canada Airworthiness Directive CF-2007-15 dated 24 August 2007 refers.

\n```\n\n| Compliance: | 1. Unless already accomplished, no later than 25 flight hours or 30 days from the effective date of this directive, whichever comes first.2. Within 10 flight hours, after the completion of requirement 1.3. Within 300 flight hours or at next scheduled inspection, whichever comes first, after the completion of requirement 1.4. After the effective date of this Airworthiness Directive. |\n| ----------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ |\n| | This Airworthiness Directive becomes effective on 3 October 2007. |\n| Background: | Transport Canada has determined that disc assemblies part number (P/N) 36300-1, 37855-1 and C048354-1 manufactured between 1 November 2005 and 30 November 2006, may have discs of improper thickness or discs may have been indexed incorrectly. |\n\n![](image.001.png) \nDavid Villiers \nDelegate of the Civil Aviation Safety Authority\n\n28 September 2007","sortOrder":0},{"sectionNumber":"AD/BELL 430/12","sectionType":"part","heading":"AD/BELL 430/12","content":"## AD/BELL 430/12","sortOrder":1},{"sectionNumber":"Disc Assemblies - Tail Rotor Driveshaft","sectionType":"part","heading":"Disc Assemblies - Tail Rotor Driveshaft","content":"## Disc Assemblies - Tail Rotor Driveshaft","sortOrder":2},{"sectionNumber":"12/2007 DM","sectionType":"part","heading":"12/2007 DM","content":"## 12/2007 DM","sortOrder":3}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":3,"scope_assessment":{"changed":false,"description":"This is a standard airworthiness directive with a focused, single-purpose scope: addressing a specific manufacturing defect in particular helicopter models. The scope remains tightly constrained to the identified safety issue without expansion into broader operational or maintenance requirements."},"complexity_factors":["Multiple part numbers with different technical specifications (thickness tolerances vary by part number)","Conditional logic: different actions required depending on manufacturing date and inspection results","Staggered compliance deadlines tied to flight hours and calendar days, with dependencies between requirements","Cross-reference to external technical document (BHTC Alert Service Bulletin ASB-430-07-40) for detailed inspection procedures","Reference to Canadian aviation authority directive (Transport Canada CF-2007-15) for background context"],"plain_english_summary":"This AD requires owners/operators of Bell 430 helicopters (S/N up to 49120) fitted with disc assemblies P/N 36300-1, 37855-1 or C048354-1 to inspect those tail-rotor driveshaft discs for correct manufacturing date, thickness and indexing per the manufacturer’s service bulletin, and remove non‑conforming or misindexed parts. \n\nInspections are mandated within 25 flight hours or 30 days; removal and an immediate installation ban for non‑compliant discs prevent possible driveshaft failure and loss of control."},"flash_summary_failed":{"failed":true,"reason":"Unauthenticated. Configure AI_GATEWAY_API_KEY or use a provider module. Learn more: https://ai-sdk.dev/unauthenticated-ai-gateway","source":"analysis-cron"},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"Scope aligns with the instrument's stated Applicability and Background: it targets Bell 430 helicopters S/N up to 49120 fitted with the three listed disc assembly P/Ns manufactured between 1 Nov 2005 and 30 Nov 2006, requiring inspection/removal and prohibiting re-installation unless ASB-compliant (Applicability; Background; Requirements 1–4). No expansion or narrowing beyond those stated limits is indicated in the text."},"complexity_factors":["Narrow applicability defined by helicopter serial number and three specific part numbers (Applicability).","Inspection requires verification of manufacturing date, total thickness against tight numeric tolerances, and correct indexing (Requirement 1; table under Requirement 2).","Multiple discrete outcomes: logbook entry if OK, removal if out of tolerance, removal if mis-indexed, and prohibition on re-installation unless ASB-compliant (Requirements 1–4).","Deadlines expressed in flight hours and calendar days, and a mix of immediate and scheduled inspection windows (Compliance: 25 flight hours/30 days; 10 flight hours; 300 flight hours/next inspection).","Must follow an external service bulletin (BHTC ASB-430-07-40) or approved revisions, creating dependence on manufacturer instructions and approval processes (Requirement 1; Requirement 4).","Cross-reference to a foreign authority directive (Transport Canada AD CF-2007-15) adds a regulatory provenance point to consider (Note).","Operational burdens: measurement equipment, access to tail rotor driveshaft discs, potential need for replacement parts and associated downtime (implied by removal/repair requirements)."],"plain_english_summary":"Requires owners/operators of Bell 430 helicopters S/N up to 49120 fitted with disc assemblies P/N 36300-1, 37855-1 or C048354-1 to verify manufacturing date, thickness and indexing against BHTC ASB‑430‑07‑40, remove any discs outside the specified thickness or improperly indexed, and prohibit re-installation unless ASB-compliant. Transport Canada identified discs made 1 Nov 2005–30 Nov 2006 as potentially affected. It affects operators, maintenance organisations and parts suppliers by imposing inspections, removals, logbook entries and short-term operational interruptions under set flight‑hour/day deadlines."}},"importantCases":[],"_links":{"self":"/api/acts/ad-bell-430-12-disc-assemblies-tail-rotor-driveshaft","history":"/api/acts/ad-bell-430-12-disc-assemblies-tail-rotor-driveshaft/history","analysis":"/api/acts/ad-bell-430-12-disc-assemblies-tail-rotor-driveshaft/analysis","conflicts":"/api/acts/ad-bell-430-12-disc-assemblies-tail-rotor-driveshaft/conflicts","importantCases":"/api/acts/ad-bell-430-12-disc-assemblies-tail-rotor-driveshaft/important-cases","documents":"/api/acts/ad-bell-430-12-disc-assemblies-tail-rotor-driveshaft/documents"}}