Summary and Key Points: On October 3, 1967, test pilot William “Pete” Knight flew the rocket-powered X-15 to Mach 6.7 — about 4,520 mph — a speed no crewed aircraft has matched in nearly 60 years.

NASA and Boeing have effectively cancelled the X-66 Transonic Truss-Braced Wing (TTBW) concept demonstrator aircraft. Officially described as a "pause," development of the thin-wing airplane is being ...

The R&D zone within an aircraft factory is often shrouded in mystery, bearing top secret fruit. But some of the most innovative technologies to streak through the skies have sprung from collaborations ...

Even though the X-29 successfully proved new technologies, it did not result in the development of forward-swept-wing fighter ...

The X-62 Variable Stability In-flight Simulator Test Aircraft will incorporate advanced radar and sensor integration to allow autonomy testing in more complex scenarios. The U.S. Air Force has ...

Aerodynamic and structural data on the X-66 were obtained from wind tunnel tests of a 5.3%-scale model in the Transonic Unitary Plan Facility at NASA’s Ames Research Center in California. Credit: ...

DARPA's X-65, that replaces conventional aircraft flight controls with puffs of air, is coming together at Boeing subsidiary Aurora’s Bridgeport, West Virginia facility. The fuselage is taking shape ...

DARPA has initiated an effort to build a new, stealthy spy plane. Unlike other aircraft, this X-plane will feature a hybrid electric propulsion system. The XRQ-73 will be much quieter than traditional ...

NASA's X-59 quiet supersonic research aircraft is preparing for some of its most significant flights yet. The X-plane is about to begin a new block of test flights that will include its first time ...