Boeing's Secret Bird of Prey Stealth Jet: A $67 Million Experiment in Stealth Technologies

In 1992, McDonnell Douglas initiated the YF-118G Bird of Prey project at its Phantom Works division. The goal was to test stealth technologies without incurring significant costs. This approach allowed engineers to explore ways to make aircraft harder to detect, a crucial aspect of stealth that doesn't render an aircraft invisible.

The YF-118G measured approximately 47 feet long with a 23-foot wingspan and weighed about 7,400 pounds. It was powered by a Pratt & Whitney JT15D-5C turbofan engine and had an eventual operating speed of 260 knots (around 300 miles per hour). Despite its modest specifications, the Bird of Prey never intended to engage in real combat.

Boeing acquired McDonnell Douglas in 1997, taking over the project. The company revealed the YF-118G in October 2002, after it had already completed three years of flight testing. Over its lifespan, the aircraft made 38 test flights at a cost of $67 million.