{"abstract":"We propose to adopt a new airworthiness directive (AD) for certain Bombardier, Inc. Model BD-100-1A10 (Challenger 300) airplanes. This proposed AD was prompted by reports of failure of a screw cap or end cap of the auxiliary hydraulic system accumulator while on the ground, which resulted in loss of use of that hydraulic system and high-energy impact damage to adjacent systems and structures. This proposed AD would require inspecting for the correct serial number of a certain hydraulic system accumulator, and replacing affected hydraulic system accumulators with new or serviceable accumulators. We are proposing this AD to prevent failure of a screw cap or end cap and loss of the related hydraulic system, which could result in damage to airplane structure and consequent reduced controllability of the airplane.","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/2012/09/06/2012-21946.html","cfr_references":[{"chapter":null,"citation_url":null,"part":39,"title":14}],"citation":"77 FR 54846","comment_url":null,"comments_close_on":"2012-10-22","correction_of":null,"corrections":[],"dates":"We must receive comments on this proposed AD by October 22, 2012.","disposition_notes":null,"docket_ids":["Docket No. FAA-2012-0930","Directorate Identifier 2011-NM-251-AD"],"dockets":[],"document_number":"2012-21946","effective_on":null,"end_page":54848,"executive_order_notes":null,"executive_order_number":null,"explanation":null,"full_text_xml_url":"https://www.federalregister.gov/documents/full_text/xml/2012/09/06/2012-21946.xml","html_url":"https://www.federalregister.gov/documents/2012/09/06/2012-21946/airworthiness-directives-bombardier-inc-airplanes","images":{},"images_metadata":{},"json_url":"https://www.federalregister.gov/api/v1/documents/2012-21946?publication_date=2012-09-06","mods_url":"https://www.govinfo.gov/metadata/granule/FR-2012-09-06/2012-21946/mods.xml","not_received_for_publication":null,"page_length":3,"page_views":{"count":50,"last_updated":"2026-04-04 18:15:03 -0400"},"pdf_url":"https://www.govinfo.gov/content/pkg/FR-2012-09-06/pdf/2012-21946.pdf","presidential_document_number":null,"proclamation_number":null,"public_inspection_pdf_url":"https://public-inspection.federalregister.gov/2012-21946.pdf?1346849675","publication_date":"2012-09-06","raw_text_url":"https://www.federalregister.gov/documents/full_text/text/2012/09/06/2012-21946.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":{"supporting_documents":[{"title":"U.S. DOT/FAA -  See Attachments","document_id":"FAA-2012-0930-0007"},{"title":"U.S. DOT/FAA - See Attachment","document_id":"FAA-2012-0930-0004"},{"title":"U.S. DOT/FAA - See Attachments","document_id":"FAA-2012-0930-0002"}],"regulatory_plan":{"html_url":"https://www.federalregister.gov/regulations/2120-AA64/airworthiness-directives","title":"Airworthiness Directives"},"comments_url":"https://www.regulations.gov/docketBrowser?rpp=50&so=DESC&sb=postedDate&po=0&dct=PS&D=FAA-2012-0930","supporting_documents_count":3,"docket_id":"FAA-2012-0930","regulation_id_number":"2120-AA64","title":"2011?NM?251?AD Bombardier, Inc. Model BD?100?1A10 (Challenger 300) airplanes","checked_regulationsdotgov_at":"2012-11-18T05:01:03Z"},"regulations_dot_gov_url":null,"significant":false,"signing_date":null,"start_page":54846,"subtype":null,"title":"Airworthiness Directives; Bombardier, Inc. Airplanes","toc_doc":"Bombardier, Inc. Airplanes","toc_subject":"Airworthiness Directives:","topics":["Air transportation","Aircraft","Aviation safety","Incorporation by reference","Safety"],"type":"Proposed Rule","volume":77}