traffic controllers were used in the opening sequence. The  synthesizer technician/performer was the actual engineer sent by ARP  Instruments to install the synthesizer equipment (ARP 2500) on the  set. Steven Spielberg (I) (qv) watched his expert playing of the  equipment and immediately cast him for the role. The name of the ARP  engineer is Philip Dodds (qv) and he is actually mentioned in the  credits.