Bout 850 miles. After it comes out of hypersonic speed it continues to glide and decelerate.
To those who wonder why they did this: combination of basic and applied research. It will be up to others to make practical products with this technology. Nothing new for NASA. Its predecessor NACA designed a lot of stuff you see on airplanes today -- cowlings, ducts, even the tricycle landing gear that made airplanes much safer to land (developed by NACA engineer Fred Weick).
Even some of the stuff in Rutan's SpaceShipOne design is owed to NASA research -- notably the ablative coating on the belly, and the materials of the rocket nozzle.
d.o.l.
Criminal Number 18F
Great stuff!
I think NASA should get out of the transportation business focus on pure research like we see here. The free market can take the research foundation and run with it like Rutan and Co.