AJAX Concept

The concept of a fundamentally new hypersonic vehicle has been put forward in the late eighties by Vladimir Freighstadt. He suggested not to protect vehicle flying at a great speed from the heat, but rather let it inside to augment energy resources. According to Ajax concept, a hypersonic vehicle (HV) is non-isolated aerothermodynamic system wherein at all stages of atmospheric flight a part of kinetic energy of the hypersonic airflow streamlining HV  is assimilated by the onboard subsystems increasing the vehicle’s total resource and transforming itself into chemical and electrical energy. This solved the global problem of cooling the airframe and many other issues.


A hypersonic aircraft burns hydrocarbons (kerosene or more promising fuel – liquefied methane) and water. To utilize the heat, in the double-skin of Ajax a thermochemical reactor is placed to which, following acceleration and aerodynamic heating of the skin, hydrocarbon fuel is supplied. It is used as “endothermic” fuel – i.e. for providing heat absorption. Under the action of temperature, pressure, and with the help of a catalyst, the mixture of fuel and water decomposes into olefin and free hydrogen. This hydrogen-containing mixture enters magneto-plasma-chemical engine (MPCE) constituting MHD-generator, hypersonic ramjet and located behind the combustor MHD-accelerator. MHD generator, inhibiting the flow rate to the optimum, acts as a compressor. Inhibited and pre-ionized air flow enters the combustion chamber wherein hydrogen-enriched fuel (kerosene or methane) is fed. Exhausting products of combustion enter the nozzle, pick up speed with the help of MHD-accelerator and, expanding, go outside.

To accelerate the flow and ionize the air, i.e. a “cold plasma” formation, electric energy generated by the MHD-generator is used. It allows the increase of the vehicle’s speed by 10–30 % and getting a lot of advantages, too. Plasma funnel around the scramjet inlet increases its effective diameter, which rises almost to a hundred meters, plasma spots-clouds in front of the vehicle significantly reduce air resistance and near the wings – increase their effective area and regulate the lift. For air ionization it is possible to use laser radiation or neutron source. Thus, the vehicle flying in the atmosphere will be able to convert kinetic energy of the ram air into a wide range of different types of energy and use on-board energy complex with a capacity of 100 megawatt for a variety of global nature tasks. 

A differential peculiarity of the Ajax concept is its integrity from the energy point of view. Various scientific and technological approaches are organically linked in it: