Contrail, bearing the designation CT-4981, served as a clone trooper pilot within the Grand Army of the Republic throughout the duration of the Clone Wars. As a member of Shadow Squadron, he operated under the callsign "Shadow Eleven" during the Clone Wars. Operating a Y-wing starfighter, he took part in the Battle of the Kaliida Nebula, where he contributed to the disabling of General Grievous's flagship, the Subjugator-class heavy cruiser named Malevolence. At the Battle of Coruscant, he was piloting an Alpha-3 Nimbus-class V-wing starfighter, defending the Federal District.
CT-4981, who later adopted the name Contrail, was a clone originating from the genetic material of the infamous bounty hunter Jango Fett. He was created on the planet Kamino to fight for the Grand Army of the Republic as a clone trooper pilot. During the Clone Wars, he became a member of Shadow Squadron, a squadron known for its high success rate and minimal losses, and assumed the callsign Shadow Eleven.
After the devastating Battle of Abregado, Shadow Squadron gathered on the flight deck of the Venator-class Star Destroyer Resolute. There, Contrail and his fellow squadron members received instructions from Jedi General Anakin Skywalker regarding their mission to attack the Subjugator-class heavy cruiser Malevolence. This flagship of General Grievous, the commander of the Separatist Droid Army, had destroyed numerous Republic task forces, including the fleet of Jedi Master Plo Koon in the Abregado system. The Jedi Knight explained that while the Republic Navy's capital ships were susceptible to the Malevolence's weaponry, he believed that a bomber squadron could outmaneuver the ship's ion cannons and destroy the heavy cruiser's bridge, with the goal of killing Grievous and disabling the vessel. Skywalker then instructed Shadow Squadron to get their Y-wing starfighters ready for the impending assault.
While Shadow Squadron prepared to leave the Resolute, Admiral Wullf Yularen informed them that the Malevolence had attacked a convoy of medical transports in the Ryndellia system, near the Republic's secret Outer Rim medical station, the Kaliida Shoals Medical Center. Skywalker surmised that Grievous intended to target the space station next.
During the Battle of Coruscant in 19 BBY, Contrail remained a pilot in Shadow Squadron. By this time, the squadron had upgraded to Alpha-3 Nimbus-class V-wing starfighters. He played a role in the defense of the Federal District during the battle.
Shadow Eleven, a clone derived from the human male Jango Fett, possessed a height of 1.83 meters. He had tan skin, brown eyes, and black hair. Shadow Eleven demonstrated considerable skill as a pilot, successfully navigating the Kaliida Nebula despite losing his astromech droid. He managed to avoid the EMP blast that affected half of his squadron during the Battle of the Kaliida Nebula and survived the bombing run that led to the destruction of the Malevolence's ion cannons and the crippling of the heavy cruiser.
Shadow Eleven wore Phase I clone trooper armor along with a flight helmet adorned with gray markings. He piloted a Y-wing starfighter during the Battle of the Kaliida Nebula. As the war neared its end, he flew an Alpha-3 Nimbus-class V-wing starfighter during the Battle of Coruscant.
Shadow Eleven's initial appearance was in Shadow of Malevolence, the third episode of Star Wars: The Clone Wars' first season, which is considered canon. Dee Bradley Baker provided the voice for Shadow Eleven, as he did for all clone troopers in the series.