create terminal control areas or TCAs (now called Class B airspace) around the busiest airports in the country. The airspace around Dayton did not become a TCA, undergoing only minor changes until it was reclassified as Class C airspace in the late 1980s. References External links Airliners.net Flight 553 preparing for departure in a photo by Bob Garrard, 1967 National Transportation Safety Board Report AAR68 on the crash () 1967 in Ohio Airliner accidents and incidents in Ohio Aviation accidents and incidents in the United States in 1967 Mid-air collisions Mid-air collisions involving airliners Mid-air collisions involving general aviation aircraft 553 Accidents and incidents involving the McDonnell Douglas DC-9 Champaign County, Ohio March 1967 events in the United States