In addition, a limited number of period gun-ciné films were also used, as were sequences from the films, "Memphis Belle" (1990) and "Battle of Britain" (1969). The producers also borrowed a technique used in "Memphis Belle" by using cutout silhouettes of aircraft to make it appear that there were more aircraft parked at the various airfields. One example of period dialogue that was faithful to the times was Hannibal Lee Jr. (another fictitious composite) singing: "Straighten up..." finished by Billy Roberts (fictional character): "...and fly right." (The catchphrase was derived from the 1944 top-40 hit record, "Straighten Up and Fly Right" by The King Cole Trio led by Nat King Cole.)