operator control unit (OCU)

air traffic control operator

control tower operator

control post operator

vertical control operator

fire-control operator

dual operator control

aircraft control and warning operator

early warning system (EWS) operator

identification operator

operator maintenance

operator’s pack

operator's permit

ship operator

telephone operator

radio telephone operator (RTO)

aiming rule operator

azimuth (deflection) display board operator

navigator-radio operator

air operator certificate

aircraft operator

airport operator

flight operator

flight radio operator

flight systems operator

operator  D / Dt

operator communication

radar operator

traffic operator

operator

radio operator

analytic equipment operator

height-finder operator