{"abstract":"This document proposes to revise an existing airworthiness directive (AD), 97-06-13, applicable to certain Rolls-Royce plc (R-R) RB.211 Trent 800 series turbofan engines, that currently requires initial and repetitive inspections of the angled drive upper shroud, the intermediate gearbox housing (IGH), and the external gearbox lower bevel box (LBB) housing. In addition, that AD requires initial and repetitive master magnetic chip detector (MCD) inspections. Finally, prior to initiation of Extended-Range Operations with Two-Engine Aircraft (ETOPS), or prior to September 30, 1997, whichever occurs first, AD 97-06-13 requires installation of a redesigned angled drive upper shroud tube and a lower splitter fairing with revised sealing. This action would eliminate the repetitive inspections of the IGH, external gearbox LBB housing, and the angled drive upper shroud, if the engines have incorporated modifications described in certain R-R Service Bulletins (SBs) . In addition, this action would increase the inspection interval for repetitive master MCD inspections. This proposal is prompted by service experience since publication of AD 97- 06-13. The actions specified by the proposed AD are intended to prevent loss of oil, which could cause an engine fire. This proposed AD is also intended to prevent in-flight engine shutdowns and airplane diversions caused by oil loss and bearing failures.","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/1999/11/02/99-28522.html","cfr_references":[{"chapter":null,"citation_url":null,"part":39,"title":14}],"citation":"64 FR 59137","comment_url":null,"comments_close_on":"2000-01-03","correction_of":null,"corrections":[],"dates":"Comments must be received by January 3, 2000.","disposition_notes":null,"docket_ids":["Docket No. 97-ANE-09"],"dockets":[],"document_number":"99-28522","effective_on":null,"end_page":59139,"executive_order_notes":null,"executive_order_number":null,"explanation":null,"full_text_xml_url":null,"html_url":"https://www.federalregister.gov/documents/1999/11/02/99-28522/airworthiness-directives-rolls-royce-plc-model-rb211-trent-892-884-877-875-and-892b-series-turbofan","images":{},"images_metadata":{},"json_url":"https://www.federalregister.gov/api/v1/documents/99-28522?publication_date=1999-11-02","mods_url":"https://www.govinfo.gov/metadata/granule/FR-1999-11-02/99-28522/mods.xml","not_received_for_publication":null,"page_length":3,"page_views":{"count":11,"last_updated":"2026-04-04 12:15:04 -0400"},"pdf_url":"https://www.govinfo.gov/content/pkg/FR-1999-11-02/pdf/99-28522.pdf","presidential_document_number":null,"proclamation_number":null,"public_inspection_pdf_url":null,"publication_date":"1999-11-02","raw_text_url":"https://www.federalregister.gov/documents/full_text/text/1999/11/02/99-28522.txt","regulation_id_number_info":{},"regulation_id_numbers":[],"regulations_dot_gov_info":{"checked_regulationsdotgov_at":"2011-09-21T11:53:09Z"},"regulations_dot_gov_url":null,"significant":null,"signing_date":null,"start_page":59137,"subtype":null,"title":"Airworthiness Directives; Rolls-Royce plc Model RB211 Trent 892, 884, 877, 875, and 892B Series Turbofan Engines","toc_doc":null,"toc_subject":null,"topics":[],"type":"Proposed Rule","volume":64}