NASA’s Sustainable Flight Demonstrator project completed wind tunnel tests on a Boeing-built X-66 full-span model during a 13-week campaign between January and March 2025. The tests were completed in the 11-Foot Transonic Unitary Plan Facility at NASA’s Ames Research Center in California’s Silicon Valley. The model underwent tests in expected flight conditions to obtain engineering data to help improve the aircraft’s design and flight simulators.

Boeing’s MD-90 aircraft flies from Victorville California to Palmdale, California on August 15, 2023. This aircraft will be NASA’s future Sustainable Flight Demonstrator. Modifications to the aircraft will include changes to the fuselage and most notably the use of a transonic truss-braced wing.

Boeing’s MD-90 aircraft flies from Victorville California to Palmdale, California on August 15, 2023. This aircraft will be NASA’s future Sustainable Flight Demonstrator. Modifications to the aircraft will include changes to the fuselage and most notably the use of a transonic truss-braced wing.

Boeing’s MD-90 aircraft flies from Victorville California to Palmdale, California on August 15, 2023. This aircraft will be NASA’s future Sustainable Flight Demonstrator. Modifications to the aircraft will include changes to the fuselage and most notably the use of a transonic truss-braced wing.

A model of the X-66 aircraft with a wingspan of almost 6 feet was placed in the 12-Foot Low-Speed Wind Tunnel at NASA’s Langley Research Center in Hampton, Virginia on October 30, 2024. During the tests, the team captured measurements of forces such as lift and drag over many aerodynamic configurations and flight conditions.

Boeing’s MD-90 aircraft flies from Victorville California to Palmdale, California on August 15, 2023. This aircraft will be NASA’s future Sustainable Flight Demonstrator. Modifications to the aircraft will include changes to the fuselage and most notably the use of a transonic truss-braced wing.

Eric Garza, an engineering technician in the Experimental Fabrication Shop at NASA’s Armstrong Flight Research Center in Edwards, California, cuts plywood to size for temporary floorboards for the X-66 experimental demonstrator aircraft on Aug. 26, 2024.

A wood router cuts precise holes in plywood for temporary floorboards on Aug. 26, 2024, in the Experimental Fabrication Shop at NASA’s Armstrong Flight Research Center in Edwards, California. The flooring was designed for the X-66 experimental demonstrator aircraft.

Boeing’s MD-90 aircraft flies from Victorville California to Palmdale, California on August 15, 2023. This aircraft will be NASA’s future Sustainable Flight Demonstrator. Modifications to the aircraft will include changes to the fuselage and most notably the use of a transonic truss-braced wing.

A model of the X-66 aircraft with a wingspan of almost 6 feet was placed in the 12-Foot Low-Speed Wind Tunnel at NASA’s Langley Research Center in Hampton, Virginia on October 30, 2024. During the tests, the team captured measurements of forces such as lift and drag over many aerodynamic configurations and flight conditions.

Boeing’s MD-90 aircraft flies from Victorville California to Palmdale, California on August 15, 2023. This aircraft will be NASA’s future Sustainable Flight Demonstrator. Modifications to the aircraft will include changes to the fuselage and most notably the use of a transonic truss-braced wing.

Eric Garza, an engineering technician in the Experimental Fabrication Shop at NASA’s Armstrong Flight Research Center in Edwards, California, observes a wood router cut holes for temporary floorboards on Aug. 26, 2024. The flooring was designed for the X-66 experimental demonstrator aircraft. 

Boeing’s MD-90 aircraft flies from Victorville California to Palmdale, California on August 15, 2023. This aircraft will be NASA’s future Sustainable Flight Demonstrator. Modifications to the aircraft will include changes to the fuselage and most notably the use of a transonic truss-braced wing.

The cockpit of an old MD-90 aircraft arrived at NASA’s Armstrong Flight Research Center in Edwards, California, in March 2024. Parts will be used to build a simulator for NASA’s X-66, the demonstration aircraft for the Sustainable Flight Demonstrator project.

The cockpit of an old MD-90 aircraft arrived at NASA’s Armstrong Flight Research Center in Edwards, California, in March 2024. Parts will be used to build a simulator for NASA’s X-66, the demonstration aircraft for the Sustainable Flight Demonstrator project.

NASA’s Sustainable Flight Demonstrator project concluded wind tunnel testing in the fall of 2024. Tests on a Boeing-built X-66 model were completed at NASA’s Ames Research Center in California’s Silicon Valley in the 11-Foot Transonic Unitary Plan Facility. The model underwent tests representing expected flight conditions to obtain engineering information to influence design of the wing and provide data for flight simulators.

NASA’s Sustainable Flight Demonstrator project concluded wind tunnel testing in the fall of 2024. Tests on a Boeing-built X-66 model were completed at NASA’s Ames Research Center in Silicon Valley, California, in the 11-Foot Transonic Unitary Plan Facility. Pressure points, which are drilled holes with data sensors attached, are installed along the edge of the wing and allow engineers to understand the characteristics of airflow and will influence the final design of the wing.