According to
XCOR aerospace's website: "The EZ-Rocket is a modified
Long-EZ homebuilt aircraft. The aircraft is powered by twin 400 lb thrust regeneratively cooled rocket engines. The EZ-Rocket includes an external composite fuel tank and an insulated internal aluminum liquid oxygen tank. The modifications were performed at XCOR Aerospace's Mojave, CA shop. Tests are performed at the Mojave Civilian Flight Test Center."
The rocket fuel used is isopropyl alcohol and LOX. Alcohol is employed as the team discovered during their work at Rotary Rocket that use of kerosene leads to stubbon, flammable deposits in the engine; that may explode unless removed. Therefore a fuel that evaporates away clean is extremely desirable. They evaluated ethanol, but regulatory issues makes that an expensive option; so they opted for isopropanol, which gives excellent performance.
The engine itself is incredibly reliable- perhaps the most reliable engine ever; normal rocket engines tend to spontaneously disassemble themselves. One earlier smaller version of the engine was fired indoors, in a hall, at a Space Access conference, with an audience of over 100 people! The engine now has thousands of starts under its belt- a longer total time, and started more often, in total than all the Space Shuttles put together. The Space Shuttles are certainly no longer the only reusable rocket engines out there...
The vehicle is a modified long-EZ. Essentially they have removed the pusher propellor and engine and installed twin 400 lb rocket engines which are initially pressure fed, rather than using expensive and complicated pumps. The original fuel tanks were the wrong shape for pressurised fuel, and instead an external cylindrical tank was fitted, underslung below the airframe.
The pilot is Dick Rutan famous for circumnavigating the world non-stop; who's brother Burt Rutan also incidentally designed the Long-EZ that the design is based upon.
With a total burn time of just a couple of minutes, and less thrust than weight of the aircraft, this particular aircraft is never going to go into space, but it acts as a unique advertisement for the profound skills of XCOR aerospace and is acting as a predecessor that will lead to "Xerus", the space-capable aircraft they are working towards. Space Shuttle beware!