The X-66 program heavily modified a McDonnell Douglas MD-90 aircraft to demonstrate a truss-braced version of the thin wing.

Boeing and NASA are to pause development of the X-66 flight demonstrator to focus their research on the evolution of long, ...

Based on a heavily modified McDonnell Douglas MD-90, the X-66 was intended to demonstrate a truss-braced version of the thin wing at full scale. The experimental aircraft formed the flagship of NASA’s ...