"The purpose of the program is to champion the design and development of subsystem technologies and integrated air vehicle configurations that will enable radical improvements in VTOL flight," the U.S. Defense Advanced Projects Agency said in announcing a solicitation of proposals.
The VTOL X-Plane program proposals would be for the design, development and demonstration of the experimental aircraft and should be submitted to DARPA's Tactical Technology Office.
DARPA said the aircraft envisaged would be capable of sustained flight at high speeds and feature enhanced hover and cruise efficiencies.
"For the past 50 years, we have seen jets go higher and faster while VTOL aircraft speeds have flat-lined and designs have become increasingly complex," said Ashish Bagai, DARPA program manager. "To overcome this problem, DARPA has launched the VTOL X-Plane program to challenge industry and innovative engineers to concurrently push the envelope in four areas: speed, hover efficiency, cruise efficiency and useful load capacity."
2014: The Year in Music [PHOTOS]