At a media event to mark the 60th anniversary of the U-2 program, Lockheed Martin revealed that company is working on an optionally-manned successor to the spy plane.
By United States Air Force [Public domain], via Wikimedia Commons
The new plane will utilized the same GE F118 engine and operate from 70,000ft and above. The key distinction is that it will be able to survive in hostile environment thanks to a low-observable airframe.