Boeing X-45

Background

The X-45 was developed from research gathered during the development of the Bird of Prey, a stealth technology demonstrator. Boeing stated that Bird of Prey 'paved the way' for the X-45 by proving out stealth shaping and construction methods. After McDonnell Douglas merged with Boeing, the stealth knowledge from Bird of Prey was carried into Boeing Phantom Works, which designed the X-45. The aircraft features an extremely low-profile dorsal intake near the leading edge, a blended center fuselage into a swept lambda wing, a small exhaust outlet, and no vertical control surfaces—split ailerons near each wingtip function as asymmetric air brakes for rudder control, similar to Northrop's flying wings.

X-45A

Two X-45A proof-of-concept aircraft were built, the first completed in September 2000. The X-45A had its first flight on May 22, 2002, and the second vehicle flew in November 2002. On April 18, 2004, the X-45A successfully hit a ground target with a 250 lb inert precision-guided munition at Edwards Air Force Base.

On August 1, 2004, two X-45As were controlled in flight simultaneously by one ground-based pilot for the first time. On February 4, 2005, on their 50th flight, the two X-45As autonomously determined which vehicle held the optimum position, weapons, and fuel load to attack a target, then one changed course and the ground pilot authorized the strike. After a successful strike, a second simulated threat was destroyed by the other X-45A, demonstrating autonomous teaming and engagement of previously undetected targets.

X-45B/C

The larger X-45B design was modified into the X-45C with more fuel capacity and three times greater combat range. The X-45C included an F404 engine. DARPA awarded $767 million in October 2004 for three X-45C aircraft, and an additional $175 million in July 2005 to continue the program and implement autonomous aerial refueling. On March 2, 2006, the US Air Force decided not to continue with the X-45 project.

X-45N

Boeing then submitted a proposal for a carrier-based demonstrator, the X-45N, to the Navy's Unmanned Combat Air Systems demonstration project. The contract was awarded to Northrop Grumman's X-47, ending the X-45 program. Boeing later used the X-45C prototype for an internally funded program called Phantom Ray.