Lockheed Martin SR-72
The Lockheed Martin SR-72, colloquially referred to as "Son of Blackbird",[1] is an American hypersonic UAV concept intended for intelligence, surveillance and reconnaissance (ISR) proposed privately in 2013 by Lockheed Martin as a successor to the retired Lockheed SR-71 Blackbird. In 2018, company executives said an SR-72 test vehicle could fly by 2025 and enter service in the 2030s.
The SR-71 Blackbird was retired by the United States Air Force in 1998,[2] eliminating a unique and useful intelligence, surveillance and reconnaissance (ISR) capability. Though most fifth-generation jet fighters and projected drones intended to operate in enemy airspace incorporated anti-radar stealth technologies, some came to believe that the growth of anti-access/area denial tactics and counter-stealth technologies meant that speed, not stealth, was the most promising approach to penetrating protected airspace.[3]
The first unconfirmed reports about the SR-72 appeared in 2007, when various sources disclosed that Lockheed Martin was developing an airplane able to fly six times the speed of sound or Mach 6 (4,000 mph; 6,400 km/h; 3,500 kn) for the Air Force.[4][5] Lockheed Martin Skunk Works' development work on the SR-72 was first published by Aviation Week & Space Technology on 1 November 2013.[6][2] Public attention to the news was large enough to overwhelm the Aviation Week servers.[7]
