The configuration of the HTV-3X combined-cycle hypersonic test vehicle being designed by Lockheed Martin's Skunk Works for the US Defense Advanced Research Projects Agency's Falcon technology demonstration has been revealed at the annual DARPATech conference.
The fighter-sized unmanned vehicle would be powered from a runway take-off to Mach 4 by turbine engines dual-mode ramjet/scramjet engines would then take it to a Mach 6 cruise. Axisymmetric "inward turning" inlets would feed both turbines and scramjets.
DARPA also reveals it is discussing a programme called Blackswift, which may be a follow-on to Falcon.
Source: FlightGlobal.com