{"as_of":"2026-10-05","attribution":"FAA and NTSB data via eFlight Registry (https://eflight.com)","connections":[{"group":"Applies to","items":[{"count":8,"name":"Lycoming IO-720-A1B","note":"","unit":"aircraft","url":"https://eflight.com/engines/lycoming-io-720-a1b#airworthiness"}],"relation":"applies to"},{"group":"System","items":[{"count":null,"name":"Engine","note":"","unit":"","url":"https://eflight.com/systems/engine"}],"relation":"about"},{"group":"More","items":[{"count":null,"name":"Every FAA order","note":"","unit":"","url":"https://eflight.com/directives"},{"count":null,"name":"Every aircraft system","note":"","unit":"","url":"https://eflight.com/systems"}],"relation":"see also"}],"graph":"https://eflight.com/graph","graph_index":"https://eflight.com/graph/index.json","license":"https://creativecommons.org/licenses/by/4.0/","node":{"effective":"2011-09-29","faa_document":"https://drs.faa.gov/browse/excelExternalWindow/E16087FCB72834448625790B00504F70.0001","id":"2011-18-09","kind":"AD","name":"Airworthiness directive 2011-18-09","published":"2011-09-14","subject":"Crankshaft failure","system":"engine","type":"directive","url":"https://eflight.com/directives/2011-18-09"},"source":"FAA Civil Aviation Registry, FAA airport file, NTSB accident database; assembled by eFlight Registry"}