{"as_of":"2026-11-06","attribution":"FAA and NTSB data via eFlight Registry (https://eflight.com)","connections":[{"group":"Applies to","items":[{"count":58,"name":"Bombardier DHC-8 Dash 8 and Q400","note":"","unit":"registered","url":"https://eflight.com/models/bombardier/dhc-8#airworthiness"},{"count":28,"name":"Dehavilland DHC-8","note":"","unit":"registered","url":"https://eflight.com/models/dehavilland/dhc-8#airworthiness"}],"relation":"applies to"},{"group":"System","items":[{"count":null,"name":"Other and general","note":"","unit":"","url":"https://eflight.com/systems/other"}],"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":"1989-12-11","faa_document":"https://drs.faa.gov/browse/excelExternalWindow/0AF39867B17B1857862569ED00599A03.0001","id":"89-23-15","kind":"AD","name":"Airworthiness directive 89-23-15","published":"","subject":"Feathering System","system":"other","type":"directive","url":"https://eflight.com/directives/89-23-15"},"source":"FAA Civil Aviation Registry, FAA airport file, NTSB accident database; assembled by eFlight Registry"}