The Convair's stubby delta wings and unusually large vertical surfaces created what was effectively a set of cruciform flight surfaces. The Pogo made some 280 tethered flights in an airship hanger before making its free flight in August 1954, with the first transitions to and from horizontal flight taking place that November. The program was cancelled in 1955 from a combination of handling problems and the realisation that the design could not match the perormance of contemporary fighter aircraft.