Since 1961 , FAR Part 91.85 had mandated speed restrictions below within 30 nautical miles of a destination airport ( the result of a previous midair collision ) , but after this accident , all areas below were prohibited from exceeding IAS . It also contributed to the Federal Aviation Administration 's decision to 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
a previous midair collision
1960 New York mid-air collision
TWA Flight 553