Even more Top Secret than the Lockheed SR-71, the D-21 drone was a promising Cold War idea that could have eliminated the need for manned overflights, although it was mostly unsuccessful. After the ...

In response to Cold War demands for safer reconnaissance, Lockheed built the D-21—a drone capable of reaching extreme speed and altitude. Despite technical success in testing, operational missions ...

Lockheed developed a spy drone in the 1960s that crashed in China. China recently debuted a supersonic drone that bears a striking resemblance to Lockheed's D-21. The D-21's urgent development was ...

The Lockheed D-21 wasn’t just fast—it was untouchable. Designed to fly at Mach 3 over enemy territory without a pilot onboard, this Cold War-era drone pushed the limits of stealth and speed. Built in ...

The Lockheed D-21 Was More Than a Mini-Version of the SR-71 Blackbird – The concept of “military drone” is one that is often associated with the 21st century, but actually ...