{"abstract":"This document proposes the adoption of a new airworthiness directive (AD) that is applicable to certain Boeing Model 707 and 720 series airplanes. This proposal would require a preventive modification of the front spar fitting on the outboard engine nacelle. This action is necessary to prevent fatigue cracking of the front spar fitting on the outboard engine nacelle, which could reduce the structural integrity of the nacelle, and result in separation of the engine from the airplane. This action is intended to address the identified unsafe condition.","action":"Notice of proposed rulemaking (NPRM).","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/2001/06/05/01-14045.html","cfr_references":[{"chapter":null,"citation_url":null,"part":39,"title":14}],"citation":"66 FR 30105","comment_url":null,"comments_close_on":"2001-07-20","correction_of":null,"corrections":[],"dates":"Comments must be received by July 20, 2001.","disposition_notes":null,"docket_ids":["Docket No. 2000-NM-378-AD"],"dockets":[],"document_number":"01-14045","effective_on":null,"end_page":30107,"executive_order_notes":null,"executive_order_number":null,"explanation":null,"full_text_xml_url":"https://www.federalregister.gov/documents/full_text/xml/2001/06/05/01-14045.xml","html_url":"https://www.federalregister.gov/documents/2001/06/05/01-14045/airworthiness-directives-boeing-model-707-and-720-series-airplanes","images":{},"images_metadata":{},"json_url":"https://www.federalregister.gov/api/v1/documents/01-14045?publication_date=2001-06-05","mods_url":"https://www.govinfo.gov/metadata/granule/FR-2001-06-05/01-14045/mods.xml","not_received_for_publication":null,"page_length":3,"page_views":{"count":9,"last_updated":"2026-04-05 00:15:04 -0400"},"pdf_url":"https://www.govinfo.gov/content/pkg/FR-2001-06-05/pdf/01-14045.pdf","presidential_document_number":null,"proclamation_number":null,"public_inspection_pdf_url":null,"publication_date":"2001-06-05","raw_text_url":"https://www.federalregister.gov/documents/full_text/text/2001/06/05/01-14045.txt","regulation_id_number_info":{"2120-AA64":{"issue":"202504","html_url":"https://www.federalregister.gov/regulations/2120-AA64/airworthiness-directives","title":"Airworthiness Directives","xml_url":"http://www.reginfo.gov/public/do/eAgendaViewRule?pubId=202504&RIN=2120-AA64&operation=OPERATION_EXPORT_XML","priority_category":"Routine and Frequent"}},"regulation_id_numbers":["2120-AA64"],"regulations_dot_gov_info":{},"regulations_dot_gov_url":null,"significant":false,"signing_date":null,"start_page":30105,"subtype":null,"title":"Airworthiness Directives; Boeing Model 707 and 720 Series Airplanes","toc_doc":"Boeing","toc_subject":"Airworthiness directives:","topics":["Air transportation","Aircraft","Aviation safety","Safety"],"type":"Proposed Rule","volume":66}