The technology of ancient Greece is the inspiration behind a new type of low-cost rocket engine that could revolutionise high-speed flight.
US engineer John Bossard has developed a rotary rocket that combines two components from conventional liquid-fueled rockets —the turbopump and combustion chamber—into one.
Bossard’s rotary rocket features angle exhaust nozzles. As exhaust gases escape from the angled nozzles, they spin the rocket. That generates a centrifugal force that pulps propellants into the combustion chamber at high pressure, boosting the escaping gases’ velocity and increasing thrust by 50 per cent overs similarly sized conventional rocket.
Bossard’s company BSRD LLC says the intrinsic simplicity of the design allows for low development and manufacturing costs.
Bossard told US Popular Mechanics magazine the fist-sized rocket was ideally suited for combined cycle engines—such as rocket/ turbojet hybrids. Such a combination engine could allow an aircraft to take off as a jet and switch to rocket power to fly faster than a jet. These aircraft could conceivably be used for hypersonic transport or sub-orbital space flights.
The Greek inspiration is in the form of an ancient steam engine—the aeolipile. This simple spinning engine consisted of a water-filled drum with angled vents that shot out steam when the assembly was heated over a fire. Hero of Alexandria described it in the first century CE.