Description

Unauthorised use of ATC frequency is a situation where a person who is not an air traffic controller pretends to be one by transmitting radio messages to aircraft. VHF communication is not subject of any protection (e.g. encryption). Therefore anyone with a radio operating in the airband (frequency range 118-137 MHz) is technically capable of listening to and sending voice messages.

Following such an "instruction" may, depending on the specific circumstances, lead to e.g. Loss of Separation, Loss of Communication, Airspace Infringement, Controlled Flight Into Terrain (CFIT) and general disruption of flight operations. Therefore, in most countries impersonating an air traffic controller is a criminal offense.

Typical signs of unauthorised transmissions include: