Tasson was a group of Delta-class DX-9 stormtrooper transports based at the Imperial research station Obsidian as part of the TIE Experimental Project. When the Rebel Alliance attacked Obsidian, Transports Tasson launched from the station to ferry pilots to Beta-class ETR-3 Escort Transport Suluk parked nearby, from where the pilots could control the prototype TIEs. This duty brought the transports under fire from the attacking B-wings and X-wings. All of Tasson was destroyed with the research station.