The Lockheed Martin SR-72, commonly known as the "Son of the Blackbird" [1], is an American hypersonic concept intended for intelligence, surveillance and reconnaissance (ISR). It was privately proposed in 2013 by Lockheed Martin as a successor to the retired Lockheed SR-71 Blackbird. As of 2025, no confirmed flight tests had been conducted and the SR-72 remains a design concept, although speculation persists about its possible entry into service in the 2030s.
