Artist HandofManos posted this stylish rendition of a Thunderbolt blueprint on DeviantArt. It's a slick five-view line art over a hexagon background. Check out his other awesome WC illustrations here.
An old design, or better said a blueprint of an already designed ship. The Thunderbolt as seen in Wing Commander III and IV.
A Terran heavy fighter its heavy ordnance made it even a threat to capital ships thanks to its capability to carry a torpedo. Even so it is less agile compared to the Hellcat or Arrow fighters