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.