In October 2002, Boeing unveiled the YF-118G Bird of Prey, a stealth demonstrator that McDonnell Douglas's Phantom Works began in 1992 and Boeing finished after the 1997 merger. It was never meant for combat: about 47 feet long, powered by a single Pratt & Whitney JT15D, and limited to 260 knots and 20,000 feet. Instead, it tested stealth shaping and cheap manufacturing, from large composite structures to disposable tooling, and its lessons shap…