The Pentagon's latest crack at a hypersonic aircraft is officially open for competition.

Photo: Boeing The hypersonic aircraft could potentially travel five times the speed of sound using a ramjet engine.

They hope to use high-altitude airships as a launch platform for rockets or hypersonic aircraft sent into space.

I have no idea, but we might find out if Lockheed Martin and Boeing decide to work together on the Blackswift hypersonic aircraft.