The Boeing Bird of Prey was a black project aircraft, intended to demonstrate stealth technology.
It was developed by McDonnell Douglas and Boeing in the 1990s.
The company provided $67 million of funding for the project, it was a low-cost program compared to many other programs of similar scale.
It developed technology and materials which would later be used on Boeing’s X-45 unmanned combat air vehicle.
As an internal project, this aircraft was not given an X-plane designation.
There are no public plans to make this a production aircraft.
It is characterized as a technology demonstrator.
Development of the Bird of Prey began in 1992 by McDonnell Douglas’s Phantom Works division for special projects, at Area 51.
Phantom Works later became part of Boeing Integrated Defence Systems after the Boeing McDonnell Douglas merger in 1997.
The first flight was in 1996, and 39 more flights were performed through the program’s conclusion in 1999.
The Bird of Prey was designed to prevent shadows and is believed to have been used to test active camouflage, which would involve its surfaces changing colour or luminosity to match the surroundings.
Because it was a demonstration aircraft, the Bird of Prey used a commercial off the shelf turbofan engine and manual hydraulic controls rather than fly-by-wire.
This shortened the development time and greatly reduced its cost.
The shape is aerodynamically stable enough to be flown without computer correction.
Its aerodynamic stability is in part due to lift provided by the chines, as used in other aircraft including the SR-71 Blackbird.
This provided lift for the nose in flight.
This configuration, which can be stable without a horizontal tail plane and a conventional vertical rudder, is now a standard in later stealth unmanned aerial vehicles such as the X-45 and X-47 and the tailless aircraft which use drag rudders for yaw control.
The aircraft, was given the designation “YF-118G” and was made public on October 18, 2002.