Air Force to Launch Hypersonic Test Vehicle 2 on Tues.

Air Force space officials prepare to launch first Minotaur IV

"The payload for this first launch is the Hypersonic Technology
Vehicle, or HTV, built by Defense Advanced Research Projects
Agency scientists. The Falcon HTV-2 program is an innovative
research and development joint venture of DARPA and the
Air Force to develop and demonstrate hypersonic technologies
that will help achieve a prompt global-reach capability."
http://www.af.mil/news/story.asp?id=123200332


And the Minotaur 4 is to be launching this program sometime soon.

The Space Based Space Surveillance (SBSS) system is a planned
constellation of satellites and supporting ground infrastructure that will
improve the ability of the United States Department of Defense (DoD)
to detect and track space objects in orbit around the Earth. The
primary SBSS contractor, Boeing, characterizes some orbiting space
objects as, "Potential future threats to the United States' space
assets."[1]
This capability is key to enabling the event-driven operations
concept of the future."[
http://en.wikipedia.org/wiki/Space_B...e_Surveillance


Hypersonic Cruise Vehicle

"During the early part of the flight, it acts like a spacecraft. In the
middle phase, the HTV reenters the atmosphere like the
Space Shuttle, and in the latter stage, it flies like an aircraft."
"For the second glided demonstration, scheduled for 2008
or 2009, the Falcon HTV-2 will feature a different structural
design, enhanced controllability, and higher risk, performance
factors during its high-speed journey. Like its predecessor, the
system will reach Mach 22 speed, and then finish its one-hour
plus mission in the Pacific Ocean.
http://www.globalsecurity.org/space/systems/hcv.htm