Known for the distinctive "sharkmouths" decoration on their noses, P-40 fighters first saw combat in China during World War II.Their most common adversary was the Japanese Nakajima Ki-43, nicknamed "Oscar." Carl Molesworth describes and explains the design and development of these two foes, the products of two vastly different philosophies of fighter design. The P-40 was heavily armed and sturdy with armor protection and self-sealing fuel tanks, but paid for this with the loss of speed and a sluggish performance at altitude.