{"as_of":"2026-10-05","attribution":"FAA and NTSB data via eFlight Registry (https://eflight.com)","connections":[{"group":"Applies to","items":[{"count":5,"name":"Ag-Cat Corporation G-164","note":"","unit":"registered","url":"https://eflight.com/models/ag-cat-corporation/g-164#airworthiness"},{"count":64,"name":"Schweizer Aircraft Corp G-164","note":"","unit":"registered","url":"https://eflight.com/models/schweizer-aircraft-corp/g-164#airworthiness"}],"relation":"applies to"},{"group":"System","items":[{"count":null,"name":"Flight controls","note":"","unit":"","url":"https://eflight.com/systems/flight-controls"}],"relation":"about"},{"group":"Related orders","items":[{"count":null,"name":"Replaces 78-08-09","note":"","unit":"","url":"https://eflight.com/directives/78-08-09"},{"count":null,"name":"Replaced by 2011-05-07","note":"","unit":"","url":"https://eflight.com/directives/2011-05-07"}],"relation":"related to"},{"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":"2008-12-19","faa_document":"https://drs.faa.gov/browse/excelExternalWindow/39C9D1AB08E4548386257501005201F6.0001","id":"2008-22-21","kind":"AD","name":"Airworthiness directive 2008-22-21","published":"2008-11-14","subject":"Main tubular spar","system":"flight-controls","type":"directive","url":"https://eflight.com/directives/2008-22-21"},"source":"FAA Civil Aviation Registry, FAA airport file, NTSB accident database; assembled by eFlight Registry"}