Abstract: A rotary engine is provided with solid vanes which extend through the rotor and engage opposing interior wall portions of the stator housing. A series of grooves in the interior wall permit the expanding exhaust gases to by-pass the minimal surface area of vanes proximate to the combustion chamber to engage the larger surface area of a vane which is protruding more significantly from the rotor. This robust rotary engine is preferably made of cast iron, having internal portions coated with ceramic so that it readily can operate at temperatures exceeding 850° F. The heat energy is utilized to obtain maximum productive work rather than being discarded as a waste product as is typical with most state of the art power plants, resulting in an efficiency rating exceeding 60%.