Giant Killer (call sign)

GIANT KILLER is a military Air Traffic Control (ATC) Call Sign used within certain regions of the contiguous United States (CONUS). The call sign is given to a controller responsible for flight operations within restricted military airspace. The call sign is commonly published in NOTAMs that designate restricted airspace reserved for military flight operations or combat exercises where normal airspace separation rules do not apply . Previous to the use of the call sign, no standardized identification method existed for military air traffic controllers to identify themselves to civilian or military aircraft.

To reduce the confusion and to ensure standardized communication between different branches of the service, the name GIANT KILLER is used. The U.S. Military commonly uses pairs of words that do not sound phonetically similar for radio communications. This reduces the chance for confusion during transmission of critical messages. Most military ATC facilities that use the GIANT KILLER call sign maintain direct communications to weapons capable flight squadrons; the "killer" portion of the call sign may be more than a coincidence.

A significant safety concern for military combat exercise planners is the possibility of a General Aviation aircraft mistakenly entering restricted airspace while an active exercise is taking place. Added safety measures are taken when Target Drones are used during War Games. During such times, it is not uncommon for the military to release a specific safety NOTAM via the FAA. Such NOTAMs usually indicate that any aircraft in the vicinity of restricted airspace should contact GIANT KILLER on a specified frequency. This reduces the possibility that a safety mishap could occur.