Callsign CES is China Eastern
WHAT AIRLINE IS CES?
CES is the ICAO three-letter callsign prefix for China Eastern. When a radio scanner, flight tracker or radar scope shows a flight like CES123 or CES45XY overhead, that's a China Eastern aircraft talking to air traffic control.
Spot one yourself: open the live scope, enter your postcode, and tap any blip whose callsign starts with CES for its type, registration, route and photo.