Tail Sitters Return in DARPA X-Plane Program

Sikorsky and Aurora Flight Sciences have each won contracts for DARPA's VTOL X-Plane programme

Boeing may have also won an award, but declined to comment until DARPA releases more information

Sikorsky and Aurora Flight Sciences have each won contracts from the Defense Advanced Research Projects Agency (DARPA) to build a new X-Plane that combines the high-speed characteristics of fixed-wing aircraft with the hover capability of helicopters.

link.