SR-72

The Lockheed Martin SR-72, commonly referred to as "Son of Blackbird", is an American hypersonic concept intended for intelligence, surveillance, and reconnaissance (ISR). It was proposed privately in 2013 by Lockheed Martin as a successor to the retired Lockheed SR-71 Blackbird. As of 2025, no confirmed flight tests have occurred and the SR‑72 remains a design concept with speculation persisting about potential service entry in the 2030s.

Lockheed Martin publicly revealed the SR-72 concept in 2013, with development roots tracing back to the early 2000s under the Skunk Works division. The aircraft is designed to utilize a turbine-based combined cycle (TBCC) propulsion system to transition from low-speed turbojet power to high-speed scramjet power. Although rumors of a subscale flight demonstrator emerged in the late 2010s, no official prototype flights have been confirmed. The program's current status remains active but highly classified, with an operational entry target tentatively set for the 2030s.