Lockheed Martin SR-72 Lockheed Martin SR-72 The Lockheed Martin SR-72 is an American hypersonic UAV concept intended for intelligence, surveillance and reconnaissance. Lockheed Martin privately proposed it to succeed the retired Lockheed SR-71 Blackbird. The SR-71 Blackbird retired in 1998, leaving what was considered a coverage gap between surveillance satellites, manned aircraft, and unmanned aerial vehicles for intelligence, surveillance and reconnaissance (ISR) and strike missions. With the growth of anti-satellite weapons, anti-access/area denial tactics, and counter-stealth technologies, a high-speed aircraft could penetrate protected airspace and observe or strike a target before enemies could detect or intercept it. The proposed reliance on extremely high
Lockheed Martin F-35 Lightning II procurement potentially hostile Russian airspace in the event of a nuclear escalation is considered weaker than that of the F-35. Lockheed Martin offered the F-35 to Greece's Hellenic Air Force as a replacement for F-4E Peace Icarus 2000 and F-16C/D Block 30 aircraft in 2009. As of October 2017, largely due to the Greek government-debt crisis, Greece has decided to upgrade the Hellenic Air Force's fleet of ageing General Dynamics F-16 Fighting Falcon aircraft, and to postpone a decision on further procurement until the 2020s. The F-35 was reportedly still on the table, and if economically viable by the 2020 timeframe,