{"as_of":"2026-10-05","attribution":"FAA and NTSB data via eFlight Registry (https://eflight.com)","connections":[{"group":"Fitted to","items":[{"count":7,"name":"Aviat Aircraft Inc S-2","note":"","unit":"with this engine series","url":"https://eflight.com/models/aviat-aircraft-inc/s-2"},{"count":4,"name":"Aviat Inc PITTS S-2B","note":"","unit":"with this engine series","url":"https://eflight.com/models/aviat-inc/pitts-s-2b"},{"count":4,"name":"Pitts Aerobatics S-2","note":"","unit":"with this engine series","url":"https://eflight.com/models/pitts-aerobatics/s-2"},{"count":4,"name":"Slingsby Aviation Ltd SLINGSBY T67M260","note":"","unit":"with this engine series","url":"https://eflight.com/models/slingsby-aviation-ltd/slingsby-t67m260"},{"count":3,"name":"Aerotek PITTS S2S","note":"","unit":"with this engine series","url":"https://eflight.com/models/aerotek/pitts-s2s"},{"count":3,"name":"Siai-Marchetti F.260C","note":"","unit":"with this engine series","url":"https://eflight.com/models/siai-marchetti/f-260c"},{"count":3,"name":"Slingsby T67","note":"","unit":"with this engine series","url":"https://eflight.com/models/slingsby/t67"},{"count":2,"name":"Christen Industries Inc PITTS S-2B","note":"","unit":"with this engine series","url":"https://eflight.com/models/christen-industries-inc/pitts-s-2b"}],"relation":"powers"},{"group":"Where they are","items":[{"count":6,"name":"Florida","note":"","unit":"of these aircraft","url":"https://eflight.com/states/FL"},{"count":6,"name":"California","note":"","unit":"of these aircraft","url":"https://eflight.com/states/CA"},{"count":5,"name":"Texas","note":"","unit":"of these aircraft","url":"https://eflight.com/states/TX"},{"count":5,"name":"Georgia","note":"","unit":"of these aircraft","url":"https://eflight.com/states/GA"},{"count":2,"name":"Wyoming","note":"","unit":"of these aircraft","url":"https://eflight.com/states/WY"}],"relation":"registered in"},{"group":"Biggest operators","items":[{"count":2,"name":"Southern Aircraft Consultancy INC Trustee","note":"","unit":"of these aircraft","url":"https://eflight.com/fleets/southern-aircraft-consultancy-inc-trustee"},{"count":2,"name":"Eastern Stearman INC Trustee","note":"","unit":"of these aircraft","url":"https://eflight.com/fleets/eastern-stearman-inc-trustee"}],"relation":"owned by"},{"group":"Airworthiness","items":[{"count":29,"name":"FAA orders naming the Lycoming AEIO-540-D4A5","note":"","unit":"airworthiness directives","url":"https://eflight.com/engines/lycoming-aeio-540-d4a5#airworthiness"},{"count":61,"name":"Failure reports on the Lycoming AEIO-540-D4A5","note":"","unit":"reports since 1995","url":"https://eflight.com/engines/lycoming-aeio-540-d4a5#airworthiness"}],"relation":"subject to"},{"group":"Analytics","items":[{"count":null,"name":"The fleet by engine type","note":"","unit":"","url":"https://eflight.com/analytics/fleet"},{"count":null,"name":"Every engine series","note":"","unit":"","url":"https://eflight.com/engines"}],"relation":"compared in"}],"graph":"https://eflight.com/graph","graph_index":"https://eflight.com/graph/index.json","license":"https://creativecommons.org/licenses/by/4.0/","node":{"aircraft":55,"horsepower":260,"id":"lycoming-aeio-540-d4a5","maker":"Lycoming","name":"Lycoming AEIO-540-D4A5","thrust_lb":null,"type":"Piston (reciprocating)","url":"https://eflight.com/engines/lycoming-aeio-540-d4a5"},"source":"FAA Civil Aviation Registry, FAA airport file, NTSB accident database; assembled by eFlight Registry"}