like mentioned before, the thing is probably flying somewhere in the edge of space....
and to the person who was wondering why airplanes that fly that high don't go as fast; jets use turbines, not rocket engines, turbines rely on surrounding air to work, so denser air will give much more "power" while those extremely high regions won't give the engines enough power ...
rockets on the other hand have rocket propulsion that basically functions on the principle of 'conservation of momentum' and will function just as good in the atmosphere as it will in complete vacuum (not 100%true, but the idea behind it is ...)
On topic: this hyper sonic glider sounds to me like some sort of orbiting craft that will operate at the edge of space ... very much like satellites orbiting the earth, not very special, yet some of these babies will actually orbit earth at even higher speeds than this "glider", ok, they might be a bit higher up, but still not completely in outer space either ....
and if this glider is said to reach 13000mph anywhere near the surface of the earth,(lets say within 20miles of the surface) i'd like to see some accurate reports about it before i believe it ....
