Callsign UPS is UPS Airlines
WHAT AIRLINE IS UPS?
UPS is the ICAO three-letter callsign prefix for UPS Airlines. When a radio scanner, flight tracker or radar scope shows a flight like UPS123 or UPS45XY overhead, that's a UPS Airlines aircraft talking to air traffic control.
Spot one yourself: open the live scope, enter your postcode, and tap any blip whose callsign starts with UPS for its type, registration, route and photo.