{"as_of":"2026-10-30","attribution":"FAA and NTSB data via eFlight Registry (https://eflight.com)","connections":[{"group":"Applies to","items":[{"count":9,"name":"Boeing 707","note":"","unit":"registered","url":"https://eflight.com/models/boeing/707#airworthiness"},{"count":37,"name":"Boeing 727","note":"","unit":"registered","url":"https://eflight.com/models/boeing/727#airworthiness"},{"count":7,"name":"Douglas DC-9","note":"","unit":"registered","url":"https://eflight.com/models/douglas/dc-9#airworthiness"},{"count":13,"name":"Lockheed 382","note":"","unit":"registered","url":"https://eflight.com/models/lockheed/382#airworthiness"},{"count":93,"name":"Mcdonnell Douglas DC-9","note":"","unit":"registered","url":"https://eflight.com/models/mcdonnell-douglas/dc-9#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":"1979-10-08","faa_document":"https://drs.faa.gov/browse/excelExternalWindow/D77B4E4A6291728186256A3200499225.0001","id":"79-18-12","kind":"AD","name":"Airworthiness directive 79-18-12","published":"","subject":"Auxiliary Power Units","system":"engine","type":"directive","url":"https://eflight.com/directives/79-18-12"},"source":"FAA Civil Aviation Registry, FAA airport file, NTSB accident database; assembled by eFlight Registry"}