Air interceptions can occur whenever air traffic is flying over or near NATO’s European Allies, and is not in compliance with international aviation rules and regulations. The two NATO Combined Air Operations Centres (CAOCs) detect these activities within the framework of NATO’s Air Policing mission – an enduring peacetime activity conducted 24 hours a day, 365 days a year.If NATO’s air commanders determine that a plane is behaving unusually or unsafely by flying without an identifying transponder, or refusing to respond to hails from air traffic controllers, they can send fighters to investigate. Those fighters scramble as quickly as possible to visually identify the aircraft and ascertain the nature of the problem. Often, a civilian or military aircraft has experienced a malfunction leading to a loss of communications. Sometimes, however, NATO aircraft intercept Russian military aircraft that have no flight plan or no radio communications with civilian air traffic controllers. When this behaviour occurs, NATO jets may launch to visually identify the aircraft and ensure that they are tracked as they pass by NATO airspace.