Washington: Government Printing Office, 1919. First Edition. Black & white photographs, diagrams. Original cloth. Octavo. 90, [2 folding plates] pages. Very Good. Bound in tan cloth over flexible boards with title in printed in black on upper board. Mild soil to exterior, along with some minor edge rubs and wear. Upper board is cracked near joint but neither cloth nor front pastedown are separated. Title page was over glued along inner margin with some weakness and paper transfer from subsequent separation. No disruption of image or content. Contemporaneous prior owner name penned near top edge of front pastedown.
Specifications, principles of operation, and other detailed information on this famous French revolving engine. The 80 horsepower Le Rhone 9C powered a number of military aircraft types in World War I. Revolving engines, where the crank case and cylinders rotate and the crank shaft remains stationary, were well suited for World War I aircraft. The rotating cylinders are self-cooling as they move through the air, simplifying the engine by eliminating water pump, piping, water jackets, and radiator. This manual even notes air combat advantages of this type of spinning engine, which has "...been known to come back from air battles in good flying order with bullet holes in crank case and cylinders." Furthermore, "Rifle and machine-gun bullets are ordinarily deflected by the revolving engine, which makes a good shield for the pilot when flying head-on at the enemy." Instructions for disassembly, reassembly, timing, and more, including full parts lists, photographs and diagrams--including two fold-outs.