At 20 percent scale.
Image: Aurora Flight Sciences
Designing aircraft capable of vertical takeoff and landing (VTOL) is an old goal in aeronautical engineering and military strategizing. Being able to launch attack aircraft that don't need runways means, well, not having to build runways in often inhospitable locations or dispatch aircraft carriers to unfriendly or inconvenient seas. This was the motivation behind development of the Harrier jump jet, which is capable of vertical/short takeoff and landing (V/STOL), circa the Vietnam War and it clearly remains a strategic and engineering target.
This target is also the essence of DARPA's X-Plane project, a government-funded design competition intended to produce a VTOL aircraft capable of 555 to 740 km/h, e.g. faster than any existing helicopter. Of an initial field including heavies like Sikorsky Aircraft and Boeing, DARPA picked the design put forth by Aurora Flight Sciences for actually building a test aircraft.
Last week, DARPA announced that a 325-pound, 20 percent scale flight model of the full scale demonstrator Aurora will build for DARPA, known as "LightningStrike," was successfully flown at a US military facility: "The flight of the subscale aircraft met an important DARPA risk reduction requirement, focusing on validation of the aerodynamic design and flight control system."
Here it is:
Of course, even mentioning the Harrier within the context of the X-Plane isn't quite fair.
For one thing, the proper replacement for the Harrier is to be the short take-off/vertical landing (STOVL) variant of the F-35 Lightning II, part of the Joint Strike Fighter program. But the Harrier is also just a beast, generally: an ungainly air mutant capable of about a minute of vertical burn time with a penchant for killing pilots and melting runways. By comparison, the X-plane might as well be an actual bird—feathers, hollow bones, and all.