Boeing Phantom Works developed the blended wing body (BWB) aircraft concept in cooperation with the NASA Langley Research Center.
In an initial effort to study the flight characteristics of the BWB design, a remote-controlled propeller-driven blended wing body model with a 17 ft (5.2 m) wingspan was flown in 1997.
The next step was to fly the 35 ft (10.7 m) wide X-48A in 2004, but the program was canceled before manufacturing.

Research at Phantom Works then focused on a new model, designated X-48B, two examples were built by United Kingdom-based Cranfield Aerospace, a division of Cranfield University.
Norman Princen, Boeing's chief engineer for the project, stated in 2006: "Earlier wind-tunnel testing and the upcoming flight testing are focused on learning more about the BWB's low-speed flight-control characteristics, especially during takeoffs and landings.
Knowing how accurately our models predict these characteristics is an important step in the further development of this concept."

The X-48B has a 21-foot (6.4 m) wingspan, weighs 392-pound (178 kg), and is built from composite materials.
It is powered by three small turbojet engines and is expected to fly at up to 120 kn (220 km/h) and reach an altitude of 10,000 feet (3,000 m).
 The X-48B is an 8.5% scaled version of a conceptual 240-foot span design.
 Though passenger versions of the X-48B have been proposed, the design has a higher probability of first being used for a military transport.

Wind tunnel testing on a 12 ft wide blended wing body model was completed in September 2005.
During April and May 2006, NASA performed wind tunnel tests on X-48B Ship 1 at a facility shared by Langley and Old Dominion University.
 After the wind tunnel testing, the vehicle was shipped to NASA's Dryden Flight Research Center at Edwards Air Force Base to serve as a backup to X-48B Ship 2 for flight testing.
 X-48B Ship 2 then conducted ground tests and taxi testing in preparation for flight.
 In November 2006, ground testing began at Dryden, to validate the aircraft's systems integrity, telemetry and communications links, flight-control software and taxi and takeoff characteristics.

The second X-48B was modified into the X-48C starting in 2010 for further flight tests.
The X-48C has its vertical stabilizers moved inboard on either side of the engines, and its fuselage extended aft, both to reduce the aircraft's noise profile; it was to be powered by two JetCat turbines, each producing 80 pounds-force (0.36 kN) of thrust.
 The X-48C was instead modified to use two Advanced Micro Turbo (AMT) turbojet engines in 2012.

Following flight testing of the X-48C in April 2013, Boeing and NASA announced future plans to develop a larger BWB demonstrator capable of transonic flight.
Boeing Phantom Works developed the blended wing body (BWB) aircraft concept in cooperation with the NASA Langley Research Center. In an initial effort to study the flight characteristics of the BWB design, a remote-controlled propeller-driven blended wing body model with a 17 ft (5.2 m) wingspan was flown in 1997. The next step was to fly the 35 ft (10.7 m) wide X-48A in 2004, but the program was canceled before manufacturing.
Research at Phantom Works then focused on a new model, designated X-48B, two examples were built by United Kingdom-based Cranfield Aerospace, a division of Cranfield University. Norman Princen, Boeing's chief engineer for the project, stated in 2006: "Earlier wind-tunnel testing and the upcoming flight testing are focused on learning more about the BWB's low-speed flight-control characteristics, especially during takeoffs and landings. Knowing how accurately our models predict these characteristics is an important step in the further development of this concept."
The X-48B has a 21-foot (6.4 m) wingspan, weighs 392-pound (178 kg), and is built from composite materials. It is powered by three small turbojet engines and is expected to fly at up to 120 kn (220 km/h) and reach an altitude of 10,000 feet (3,000 m).  The X-48B is an 8.5% scaled version of a conceptual 240-foot span design.  Though passenger versions of the X-48B have been proposed, the design has a higher probability of first being used for a military transport.
Wind tunnel testing on a 12 ft wide blended wing body model was completed in September 2005. During April and May 2006, NASA performed wind tunnel tests on X-48B Ship 1 at a facility shared by Langley and Old Dominion University.  After the wind tunnel testing, the vehicle was shipped to NASA's Dryden Flight Research Center at Edwards Air Force Base to serve as a backup to X-48B Ship 2 for flight testing.  X-48B Ship 2 then conducted ground tests and taxi testing in preparation for flight.  In November 2006, ground testing began at Dryden, to validate the aircraft's systems integrity, telemetry and communications links, flight-control software and taxi and takeoff characteristics.
The second X-48B was modified into the X-48C starting in 2010 for further flight tests. The X-48C has its vertical stabilizers moved inboard on either side of the engines, and its fuselage extended aft, both to reduce the aircraft's noise profile; it was to be powered by two JetCat turbines, each producing 80 pounds-force (0.36 kN) of thrust.  The X-48C was instead modified to use two Advanced Micro Turbo (AMT) turbojet engines in 2012.
Following flight testing of the X-48C in April 2013, Boeing and NASA announced future plans to develop a larger BWB demonstrator capable of transonic flight.
Boeing X-48