One end of the tube was closed and housed the injection head and aft of it, the air intakes. An ignition device was placed close to the open end of the tube. This was the airbreathing device. Bogdan, you should talk Dr. David Pratt in the Mechanical Engineering dept. He is one of the premier researchers in hypersonic air breathing propulsion.
Combustion occurs at a strong shock generated at approx.
The rear portion of the vehicle is shaped like a supersonic exhaust nozzle cut lengthwise. For rocket PDE to be effective both fuel and oxidizer would have to pulsed into a pre-combustion chamber and mixed before combustion. In June 1994 the New York Times reported it crashed.