 Although there had been a problem on its first test flight on 6 August 1952 by test pilot "Ben" Gunn, when the tailplane incidence required for takeoff in the available distance was misjudged, the P.120 exhibited pleasant flying characteristics over 11 hours of flight time.Shortly before the Farnborough Air Show of September 1952, the previously unpainted P.120 received a gloss black (with yellow trim) finish and immediately gained the nickname "Black Widowmaker.