WETA, the PBS station in Washington D.C., reports on the 19-20 July and 26-27 July 1952 (two consecutive weekends) UFO incidents over Washington, D.C.:
http://www.youtube.com/watch?v=jiCWxL9K974
The TV report contains an interview with Air Traffic Controller Howard Cocklin (Washington National Airport), who witnessed the UFO incidents.
The July 1952 UFO flap over Washington, D.C. occurred from July 13 to July 29.
“ ‘Saucer’ Outran Jet, Pilot Reveals”