4j.4 fusial thrust engines were advanced sublight drive engines manufactured by Incom Corporation for use aboard X-wing space-superiority starfighters. Providing even more power than their predecessor—the 4L4 fusial thrust engine—the 4j.4 engine was often used in Incom's XJ-series X-wings.
- The Farlander Papers
- Star Wars Screen Entertainment
- The Stele Chronicles
- The Essential Guide to Vehicles and Vessels
- Star Wars Omnibus: X-Wing Rogue Squadron Volume 1