The only vessel to be equipped with the ultra-transwarp drive was the USS Phoenix-X without the knowledge of Starfleet Command. In 2374, Dawn Relic hijacked the Phoenix-X and forced it into a premature ultra-transwarp jump. The ship landed in the Gamma Quadrant, but the ultra-transwarp components were damaged beyond repair. As a result, the only capabilities the engine was allowed to produce were transwarp and warp. ("Crash Bandicoots")