"ExtraLight Engines or XL Engines are due to advances in fusion power plant shielding. They have allowed designers to retofit their standard engines with a new and lighter shielding materials. The net result is a vastly decreased overall engine weight, thought once again, at the expense of compactness."@en . . "A fusion engine is an engine which lets two light atomic nuclei fuse to a heavier nucleus. In doing so they release a comparatively large amount of energy arising from the binding energy due to the strong nuclear force which is manifested as an increase in temperature of the reactants."@en . "ExtraLight Engines or XL Engines are due to advances in fusion power plant shielding. They have allowed designers to retofit their standard engines with a new and lighter shielding materials. The net result is a vastly decreased overall engine weight, thought once again, at the expense of compactness."@en . . "Fusion Engine"@en . "Fusion engine"@en . "A fusion engine is an engine which lets two light atomic nuclei fuse to a heavier nucleus. In doing so they release a comparatively large amount of energy arising from the binding energy due to the strong nuclear force which is manifested as an increase in temperature of the reactants."@en .