Abstract: A rotor hub for a reaction drive type helicopter includes a cylindrical sidewall having a top and an open bottom which defines an interior volume. A top plate closes the top of the cylindrical sidewall, and at least two pipe sections extend outwardly from the cylindrical sidewall. Each pipe section extends through the sidewall in communication with the interior volume. A horizontal vane is carried in an inlet of the pipe section and extends horizontally across the inlet. A three dimensional body extends downwardly from a central axis of the top plate into the interior volume.

Abstract: A rotor blade for a reaction drive type helicopter is provided. The rotor blade includes a main duct extending from a proximal end, couplable to and for fluid communication with a rotor hub, to a distal end for ducting a first air/gas stream from the rotor hub to the distal end. A nozzle is attached to an outlet of the main duct at the distal end for receiving the first air/gas stream from the main duct and releasing the first air/gas stream to propel the rotor blade. A circulation control is carried at a trailing edge of the blade. A trailing edge duct is carried intermediate the trailing edge and the main duct and is in fluid communication with the main duct by a partition with a plurality of orifices formed therein to bleed air from the main duct and generate a second air/gas stream therein with a pressure less than the pressure of the first air/gas stream. The trailing edge duct supplies the second air/gas stream to the circulation control.

Abstract: A reaction-jet helicopter with a recuperator. Hot gas exiting the recuperator is directed to the helicopter's hollow-body rotor blades to increase the energy of the air exiting the jets and thus increase thrust and improve fuel efficiency. Hot gas exiting the recuperator may also be directed to the gas turbine of the helicopter's engine, further increasing fuel efficiency. A splitter valve on the exit side of the recuperator may be employed to direct exiting gas for one or more desired uses. The recuperator includes a heat exchanger, preferably an all-prime surface heat exchanger. The recuperator system may be combined with a circulation control system on the hollow-body rotor blades to further increase fuel efficiency.