Echo Three
Echo Three served as a callsign utilized by the organization known as the Alliance to Restore the Republic.
Within the context of the Galactic Civil War, a pilot belonging to Echo Squadron and identified by this callsign took part in the battle at Fostar Haven, fighting against the Imperial military.
While the Rebel Alliance occupied Echo Base located on the ice planet of Hoth, Commander Luke Skywalker adopted this callsign as he searched the frigid landscape for signs of life.
Behind the scenes
In the 2020 video game Star Wars: Squadrons, Echo Three was designated as the callsign for a Rebel Alliance character not controlled by the player.