Evidence is mounting that the Lockheed Martin SR-72 (aka the “Son of Blackbird”) may be in production and nearing its entry into service. The United States has famously developed and produced spy planes in secret (like the F-117 Nighthawk). The Air Force is known to operate (or have in development) a number of secret or semi-secret stealth spy drones. There has been speculation in the media that the Air Force may have a spy plane that is keeping secret (there could easily be more than one secret platform).