The engine has three intake stages, which are sized according to the sound created by the combustion process when running. This has exactly the same effect as the turbine and compressor in a turbojet, creating a vacuum that sucks in air. The intakes, along with the exhaust, are sonically tuned so that the locations of the pressure antinodes of the Mach disks in the propane stream match the locations of the intake apertures. Thus atmospheric pressure augments air intake as much as possible. Early prototypes produced very small amounts of thrust, before Gluharev developed it from early experiments on producing thrust from using the pressurized fuel's kinetic energy to suck in the air and compress it prior to combustion.
