{"abstract":"This notice announces the issuance of Advisory Circular (AC) 20-146, Methodology for Dynamic Seat Certification by Analysis for Use in parts 23, 25, 27, and 29 Airplanes and Rotorcraft. The AC sets forth an acceptable means, but not the only means, for demonstrating compliance to certain sections of the regulations and the technical standard order associated with those regulations. The AC provides guidance on how to validate the computer model and under what conditions the model may be used in support of certification or TSO approval/authorization.","action":"Notice of issuance of advisory circular.","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/2003/07/02/03-16641.html","cfr_references":[],"citation":"68 FR 39616","comment_url":null,"comments_close_on":null,"correction_of":null,"corrections":[],"dates":"Advisory Circular 20-146 was issued by the Acting Manager of the Aircraft Engineering Division on May 19, 2003.","disposition_notes":null,"docket_ids":[],"dockets":[],"document_number":"03-16641","effective_on":null,"end_page":39616,"executive_order_notes":null,"executive_order_number":null,"explanation":null,"full_text_xml_url":"https://www.federalregister.gov/documents/full_text/xml/2003/07/02/03-16641.xml","html_url":"https://www.federalregister.gov/documents/2003/07/02/03-16641/advisory-circular-ac-20-146-methodology-for-dynamic-seat-certification-by-analysis-for-use-in-parts","images":{},"images_metadata":{},"json_url":"https://www.federalregister.gov/api/v1/documents/03-16641?publication_date=2003-07-02","mods_url":"https://www.govinfo.gov/metadata/granule/FR-2003-07-02/03-16641/mods.xml","not_received_for_publication":null,"page_length":1,"page_views":{"count":227,"last_updated":"2026-04-04 18:15:03 -0400"},"pdf_url":"https://www.govinfo.gov/content/pkg/FR-2003-07-02/pdf/03-16641.pdf","presidential_document_number":null,"proclamation_number":null,"public_inspection_pdf_url":null,"publication_date":"2003-07-02","raw_text_url":"https://www.federalregister.gov/documents/full_text/text/2003/07/02/03-16641.txt","regulation_id_number_info":{},"regulation_id_numbers":[],"regulations_dot_gov_info":{},"regulations_dot_gov_url":null,"significant":null,"signing_date":null,"start_page":39616,"subtype":null,"title":"Advisory Circular (AC) 20-146, Methodology for Dynamic Seat Certification by Analysis for Use in Parts 23, 25, 27, and 29 Airplanes and Rotorcraft","toc_doc":"Dynamic seat certification by analysis; methodology use in airplanes and rotorcraft","toc_subject":"Advisory circulars; availability, etc.:","topics":[],"type":"Notice","volume":68}