{"id":"F2008L00382","name":"AD/BELL 407/9 Amdt 3 - Tailboom Skin","slug":"ad-bell-407-9-amdt-3-tailboom-skin","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":72613,"registerId":"commonwealth-F2008L00382-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"Bell Helicopter Textron Canada (BHTC) 40","sectionType":"division","heading":"Bell Helicopter Textron Canada (BHTC) 407 Series Helicopters","content":"### Bell Helicopter Textron Canada (BHTC) 407 Series Helicopters\n\n| AD/BELL 407/9 Amdt 3 | Tailboom Skin | 4/2008 DM |\n| -------------------- | ------------- | --------- |\n\n| Applicability: | Model 407 helicopters with tailbooms part number 407-030-801-107 and407-530-014-101/-103 installed.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |\n| -------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n| Requirement:   | Part I - Verificationa. Verify whether tailboom part number 407-030-801-107 or 407-530-014-101/-103 is installed on the helicopter.b. Enter in the helicopter technical records the appropriate tailboom part number as identified above.c. If the tailboom identified is not affected by this Directive, annotate the helicopter technical records accordingly.Part II - Surface preparation and initial inspectionPrepare the tailboom surface for “Daily Visual Check” in accordance with Part II, paragraph (1), items (a) to (e) of BHTC Alert Service Bulletin (ASB) 407-07-80 original issue, or later Transport Canada approved revision.Inspect both areas for cracks (indicated as “Daily check area” on Figure 2 in ASB 407-07-80) using a 10x magnifying glass.If a crack is detected, before further flight, replace the tailboom.If no cracking is detected, ensure both surfaces are dry and protect each reworked area with a thin coat of clear coating in accordance with applicable paragraph of Part II, of ASB 407-07-80 original issue, or later Transport Canada approved revision.Part III - Daily Visual InspectionPerform a visual check of the tailboom in accordance with Part III, paragraphs (1) and (2) of ASB 407-07-80 original issue, or later Transport Canada approved revision.If, as a result of the Part III Daily Visual Check inspection, a crack is detected, before further flight, replace the tailboom with a serviceable part. Continue this inspection if the replacement tailboom is identified in the applicability section of this Directive. |\n\n|             | Part IV - 100 hour InspectionPerform a 100-hours inspection of the tailboom in accordance with Part IV of ASB 407-07-80 original issue, or later Transport Canada approved revision.If, as a result of the Part IV 100-hour inspection, a crack is detected, before further flight, replace the tailboom with a serviceable part. Continue this inspection if the replacement tailboom is identified in the applicability section of this Directive.Part V - Terminating actionReplacement of the affected tailboom with part number 407-030-801-201/-203/-205, or later part numbers, constitutes terminating action to this Directive.Note: Transport Canada AD CF-2008-04 refers. |\n| ----------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ |\n| Compliance: | For Part I:Within 10 flight hours after 15 February 2008.For Part II:Within 25 flight hours or 30 days after 15 February 2008, whichever occurs first.For Part III:Before the first flight of the day, during the pre-flight check.For Part IV:Within 100 flight hours after 15 February 2008, and thereafter at intervals not to exceed 100 flight hours.                                                                                                                                                                                                                                                                                                                           |\n|             | This Amendment becomes effective on 15 February 2008.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |\n| Background: | There have been several reports of cracks to the tailboom skin on the left side in the area of the horizontal stabiliser. The cracks were found by normal visual inspection.Amendment 1 limited the applicability to those helicopters equipped with certain part number tailbooms. BHTC introduced a new tailboom with a chemically milled skin which is not subject to the inspections required by this Directive.Amendment 2 introduced modifications to some of the existing tailbooms, a life limitation of 5,000 hours, and a new inspection interval of 150 hours.                                                                                                            |\n\n|     | Amendment 3 is issued in response to a new Transport Canada AD, which mandates new inspection requirements introduced by ASB 407-07-80. |\n| --- | --------------------------------------------------------------------------------------------------------------------------------------- |\n\n![](image.001.png)  \nDavid Villiers  \nDelegate of the Civil Aviation Safety Authority\n\n13 February 2008","sortOrder":0},{"sectionNumber":"AD/BELL 407/9 Amdt 3","sectionType":"part","heading":"AD/BELL 407/9 Amdt 3","content":"## AD/BELL 407/9 Amdt 3","sortOrder":1},{"sectionNumber":"Tailboom Skin","sectionType":"part","heading":"Tailboom Skin","content":"## Tailboom Skin","sortOrder":2},{"sectionNumber":"4/2008 DM","sectionType":"part","heading":"4/2008 DM","content":"## 4/2008 DM","sortOrder":3}],"analysis":{"flash_summary":{"complexity_score":6,"scope_assessment":{"changed":true,"description":"Yes. The Directive's scope has been narrowed and modified since the original: Amendment 1 limited applicability to certain tailboom part numbers; Amendment 2 added a 5,000‑hour life limit and revised inspection intervals; Amendment 3 adopts new inspection procedures from ASB 407-07-80 and provides a terminating action by replacing affected tailbooms with newer part numbers. These changes shift obligations between continued inspection and part replacement for affected operators."},"complexity_factors":["Applicability limited to specific tailboom part numbers (407-030-801-107; 407-530-014-101/-103) — requires operators to confirm and record exact part numbers.","Several distinct mandatory actions (records update, surface preparation, daily visual check, 100‑hour inspection, replacement when cracked) increasing procedural steps.","Multiple, different compliance deadlines and intervals (10 flight hours; 25 flight hours or 30 days; pre‑flight daily; within 100 flight hours and recurring every 100 hours).","Cross-references to external documents: BHTC Alert Service Bulletin ASB 407-07-80 (original or later Transport Canada approved revision) and a Transport Canada AD — creates dependency on external revisions.","Terminating action requires replacement with specified newer part numbers (407-030-801-201/-203/-205), creating parts‑availability and procurement considerations.","Interaction with earlier amendments: Amendment 1 narrowed applicability; Amendment 2 added a 5,000‑hour life limit and changed inspection intervals — historical changes affect current scope.","Technical inspection requirements (surface preparation, 10× magnifying glass, clear coat protection) impose specific maintenance skills/tools and time.","Regulatory enforcement: a CASA delegate signed the Directive and it has a fixed effective date, creating binding compliance obligations for operators."],"plain_english_summary":"Mandates inspections, record updates and, if necessary, replacement of certain Bell 407 tailbooms (part numbers 407-030-801-107 and 407-530-014-101/-103). Operators must log the tailboom part number, prepare surfaces, perform daily visual checks and 100-hour inspections, and replace any cracked tailboom before further flight; replacing with newer tailboom part numbers ends the inspection requirement. The Civil Aviation Safety Authority issues the directive and the costs of inspections, maintenance and replacement fall to helicopter owners/operators."},"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"},"kimi_summary":{"content_quality":"ok","complexity_score":4,"scope_assessment":{"changed":true,"description":"The original directive appears to have been a basic crack inspection requirement. Amendment 1 narrowed applicability to specific part numbers. Amendment 2 added modifications, life limitations (5,000 hours), and a 150-hour inspection interval. Amendment 3 (this version) introduces new inspection requirements from a revised service bulletin, changes inspection intervals (from 150 hours to 100 hours for Part IV), and references a new Transport Canada AD. The directive has evolved from a simple inspection order to a comprehensive multi-tiered inspection regime with daily, periodic, and terminating actions."},"complexity_factors":["Multiple sequential parts (I-V) with different compliance deadlines and actions","Cross-references to external documents: BHTC Alert Service Bulletin (ASB) 407-07-80 and Transport Canada AD CF-2008-04","Specific part number dependencies affecting applicability (407-030-801-107, 407-530-014-101/-103 vs terminating action parts -201/-203/-205)","Conditional logic: different actions required based on inspection results (crack detected vs not detected)","Nested compliance periods: immediate (before further flight) vs scheduled (10 hours, 25 hours/30 days, 100 hours, daily)","Amendment history references (Amendments 1, 2, and 3) indicating evolving requirements without full text of previous versions included"],"plain_english_summary":"This AD mandates owners/operators of Bell 407 helicopters with specific tailboom part numbers inspect for and, if necessary, replace tailboom skin suspected of cracking near the horizontal stabiliser, to prevent possible structural failure. It requires regular daily and periodic inspections and allows terminating action by installing the improved tailboom part numbers, making the checks unnecessary."}},"importantCases":[],"_links":{"self":"/api/acts/ad-bell-407-9-amdt-3-tailboom-skin","history":"/api/acts/ad-bell-407-9-amdt-3-tailboom-skin/history","analysis":"/api/acts/ad-bell-407-9-amdt-3-tailboom-skin/analysis","conflicts":"/api/acts/ad-bell-407-9-amdt-3-tailboom-skin/conflicts","importantCases":"/api/acts/ad-bell-407-9-amdt-3-tailboom-skin/important-cases","documents":"/api/acts/ad-bell-407-9-amdt-3-tailboom-skin/documents"}}