{"id":"F2005L02421","name":"AD/BELL 47/71 Amdt 1 - Tail Rotor Blades","slug":"ad-bell-47-71-amdt-1-tail-rotor-blades","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":36959,"registerId":"commonwealth-F2005L02421-current","compilationNumber":null,"startDate":"2026-04-01","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"Bell Helicopter Textron 47 (All Variants","sectionType":"division","heading":"Bell Helicopter Textron 47 (All Variants) Series Helicopters","content":"### Bell Helicopter Textron 47 (All Variants) Series Helicopters\n\n| AD/BELL 47/71 Amdt 1 | Tail Rotor Blades | 10/2005 |\n| -------------------- | ----------------- | ------- |\n\n| Applicability: | All model 47 with tail rotor blades P/N 47-642-117.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |\n| -------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n| Requirement:   | Carry out the requirement of Bell Technical Bulletin No. 47-05-73-1.This Directive shall be entered on the Maintenance Release as maintenance required. In addition to a Maintenance Engineer qualified on the type, the required inspection may be performed and certified by a Pilot in Command who has been trained to do the inspection by an appropriately qualified person. In this case, a copy of this Directive is to be carried in the aircraft.                                                                                                                                                                      |\n| Compliance:    | At each daily or overnight inspection.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |\n|                | This Amendment becomes effective on 29 September 2005.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |\n| Background:    | This AD was raised after several reports of cracking in the skin of the tail rotor blades. The cracks were located approximately 7 inches outboard from the butt end of the blade and approximately 1.5 inches aft of the leading edge. The cause of the cracking was found to be a burr at the tip of the retention block tang, under the blade skin. The burr chafed on the inner surface of the skin, causing a crack.This amendment is issued to alter the wording of the requirement to reflect current practice. The background of the AD was also added. There is no change to the technical requirements or compliance. |\n\n![](image.001.png)  \nDavid Villiers  \nDelegate of the Civil Aviation Safety Authority\n\n4 August 2005","sortOrder":0},{"sectionNumber":"AD/BELL 47/71 Amdt 1","sectionType":"part","heading":"AD/BELL 47/71 Amdt 1","content":"## AD/BELL 47/71 Amdt 1","sortOrder":1},{"sectionNumber":"Tail Rotor Blades","sectionType":"part","heading":"Tail Rotor Blades","content":"## Tail Rotor Blades","sortOrder":2},{"sectionNumber":"10/2005","sectionType":"part","heading":"10/2005","content":"## 10/2005","sortOrder":3}],"analysis":{"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":"The amendment alters the wording to reflect current practice but expressly states there is no change to the technical requirements or compliance. The original scope—applying to all model 47 helicopters with blade P/N 47-642-117—remains unchanged."},"complexity_factors":["Narrow applicability — applies only to Bell 47 helicopters with tail rotor blade P/N 47-642-117 (limits number of affected aircraft).","Relies on an external procedure (Bell Technical Bulletin No. 47-05-73-1) for the technical steps, so compliance requires access to and use of that document.","High-frequency compliance — inspections required at each daily or overnight check increases routine operational burden and potential downtime.","Alternative certifier option (trained Pilot in Command) adds training, certification and in‑aircraft documentation requirements compared with maintenance-only certification.","Administrative requirement to enter the Directive on the Maintenance Release and, where certified by a pilot, to carry a copy in the aircraft."],"plain_english_summary":"Requires operators of Bell 47 helicopters fitted with tail rotor blades P/N 47-642-117 to carry out the inspection procedure in Bell Technical Bulletin No. 47-05-73-1 at each daily or overnight check and record the Directive on the aircraft Maintenance Release. A Maintenance Engineer or a Pilot in Command trained to perform the check may certify it; if a pilot certifies, a copy of the Directive must be carried aboard. Operators bear the inspection and record‑keeping costs; the amendment only rewords the requirement without changing technical obligations."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This amendment explicitly states it makes no change to technical requirements or compliance timing. The scope remains exactly as originally intended: mandatory daily inspection of specific tail rotor blades for cracking."},"complexity_factors":["Very short document (under 300 words)","Only 1 defined term implicitly referenced (P/N = Part Number)","No cross-references to other legislation or regulations","Single, clear compliance requirement with one straightforward exception (pilot may substitute for engineer if trained)","No nested conditions or exceptions to exceptions","Plain language background explanation included"],"plain_english_summary":"This AD requires daily or overnight inspections of Bell 47 tail rotor blades (P/N 47‑642‑117) to detect cracks caused by a manufacturing burr that can lead to in‑flight loss of control. It applies to owners, operators and maintenance personnel; the Pilot‑in‑Command may perform the checks if trained and carrying the directive.\n\nThis Amendment 1 clarifies wording and background but does not change the inspection requirement or technical steps."}},"importantCases":[],"_links":{"self":"/api/acts/ad-bell-47-71-amdt-1-tail-rotor-blades","history":"/api/acts/ad-bell-47-71-amdt-1-tail-rotor-blades/history","analysis":"/api/acts/ad-bell-47-71-amdt-1-tail-rotor-blades/analysis","conflicts":"/api/acts/ad-bell-47-71-amdt-1-tail-rotor-blades/conflicts","importantCases":"/api/acts/ad-bell-47-71-amdt-1-tail-rotor-blades/important-cases","documents":"/api/acts/ad-bell-47-71-amdt-1-tail-rotor-blades/documents"}}