What does a Delta switch do?

• A. A maintenance procedure
• B. A signal given for an airborne crew switch
• C. A type of fuel
• D. A flight plan change

Answer: (B)

Delta switch is the signal used to tell the airborne crew to switch to Delta control or to the Delta communications channel. In CATCC operations, different controllers or channels may handle different parts of the mission, and a switch signal prompts the aircrew to change to the appropriate controller and continue communications without confusion. It’s not a maintenance procedure, not a fuel or flight plan change; it’s specifically about initiating a change in who the aircrew is talking to. When you hear or see the Delta switch, the correct action is to switch communications to the Delta controller/channel as directed and proceed with the new instructions.