Aerospace Calendar April 7-July 14—AOPA Flight Instructor Refresher Course. Various locations. See aopa.org/forms/event-calendar/FIRC_ONSITE April 9-11—Sea-Air-Space 2018. Gaylord National Convention Center. National Harbor, Maryland. See seaairspace.org April 9-12—ASCE Earth and Space 2018. Double Tree Cleveland Downtown-Lakeside. Cleveland. See earthspaceconf.mst.edu April 10-12—Aircraft Interiors Expo. Hamburg Messe. Hamburg. See ...
