{"abstract":"We are adopting a new airworthiness directive (AD) for certain Bell Model 407 helicopters. This AD requires installing a placard beneath the NR/NP dual tachometer and revising the limitations section of the rotorcraft flight manual (RFM). This AD was prompted by several incidents of third stage engine turbine wheel failures, which were caused by excessive vibrations at certain engine speeds during steady- state operations. These actions are intended to alert pilots to avoid certain engine speeds during steady-state operations, prevent failure of the third stage engine turbine, engine power loss, and subsequent loss of control of the helicopter.","action":"Final rule.","agencies":[{"raw_name":"DEPARTMENT OF TRANSPORTATION","name":"Transportation Department","id":492,"url":"https://www.federalregister.gov/agencies/transportation-department","json_url":"https://www.federalregister.gov/api/v1/agencies/492","parent_id":null,"slug":"transportation-department"},{"raw_name":"Federal Aviation Administration","name":"Federal Aviation Administration","id":159,"url":"https://www.federalregister.gov/agencies/federal-aviation-administration","json_url":"https://www.federalregister.gov/api/v1/agencies/159","parent_id":492,"slug":"federal-aviation-administration"}],"body_html_url":"https://www.federalregister.gov/documents/full_text/html/2013/10/31/2013-24030.html","cfr_references":[{"chapter":null,"citation_url":null,"part":39,"title":14}],"citation":"78 FR 65200","comment_url":null,"comments_close_on":null,"correction_of":null,"corrections":[],"dates":"This AD is effective December 5, 2013.","disposition_notes":null,"docket_ids":["Docket No. FAA-2013-0490","Directorate Identifier 2008-SW-004-AD","Amendment 39-17611","AD 2013-20-05"],"dockets":[],"document_number":"2013-24030","effective_on":"2013-12-05","end_page":65202,"executive_order_notes":null,"executive_order_number":null,"full_text_xml_url":"https://www.federalregister.gov/documents/full_text/xml/2013/10/31/2013-24030.xml","html_url":"https://www.federalregister.gov/documents/2013/10/31/2013-24030/airworthiness-directives-bell-helicopter-textron-canada-limited-bell-helicopters","images":{},"images_metadata":{},"json_url":"https://www.federalregister.gov/api/v1/documents/2013-24030?publication_date=2013-10-31","mods_url":"https://www.govinfo.gov/metadata/granule/FR-2013-10-31/2013-24030/mods.xml","not_received_for_publication":null,"page_length":3,"page_views":{"count":102,"last_updated":"2026-08-24 22:15:11 -0400"},"pdf_url":"https://www.govinfo.gov/content/pkg/FR-2013-10-31/pdf/2013-24030.pdf","presidential_document_number":null,"proclamation_number":null,"public_inspection_pdf_url":"https://public-inspection.federalregister.gov/2013-24030.pdf?1383137339","publication_date":"2013-10-31","raw_text_url":"https://www.federalregister.gov/documents/full_text/text/2013/10/31/2013-24030.txt","regulation_id_number_info":{"2120-AA64":{"issue":"202410","html_url":"https://www.federalregister.gov/regulations/2120-AA64/airworthiness-directives","title":"Airworthiness Directives","xml_url":"http://www.reginfo.gov/public/do/eAgendaViewRule?pubId=202410&RIN=2120-AA64&operation=OPERATION_EXPORT_XML","priority_category":"Routine and Frequent"}},"regulation_id_numbers":["2120-AA64"],"regulations_dot_gov_info":{"checked_regulationsdotgov_at":"2013-11-20T08:06:14Z"},"regulations_dot_gov_url":null,"significant":false,"signing_date":null,"start_page":65200,"subtype":null,"title":"Airworthiness Directives; Bell Helicopter Textron Canada Limited (Bell) Helicopters","toc_doc":"Bell Helicopter Textron Canada Limited (Bell) Helicopters","toc_subject":"Airworthiness Directives:","topics":["Air transportation","Aircraft","Aviation safety","Incorporation by reference","Safety"],"type":"Rule","volume":78}