When the last SR-71 Blackbird was grounded in 1998 it was a double blow. Not only did aviation lose one of the most advanced aircraft ever built, but also one of the most beautiful. Lockheed Martin’s Skunk Works has now revealed that it is building a successor to the Blackbird: the SR-72. Using a new hypersonic engine design that combines turbines and ramjets, the company says that the unmanned SR-72 will be twice as fast as its predecessor with a cruising speed of Mach 6.
Read the full article: Lockheed Martin developing successor to the SR-71 Blackbird