At the end of the 1960s, Dornier developed the five-seat Do132 turbine helicopter with hot-cycle reaction drive. The novel drive system was a very simple and economical craft with low maintenance requirements. The rotor system developed and tested by Dornier has the advantage over the conventional mechanical shaft drive system that no tail rotor or counter-operating second rotor is required, since the reaction drive does not generate an anti-torque moment. Since the helicopter required no shafts, gearbox, clutch and freewheel, the rotor speed was freely selectable for dynamic take-offs with considerable overload.
The resulting total weight of the dynamic system resulted in a very favourable payload-to-empty-weight ratio. A gas generator of the UACL PT6 A-20 type supplied the hot compressed gas for the rotor. From the turbine, the gas was fed to the thrust nozzles at the blade tips, via the rotor head and the blades. The rotor-system was tested on a rotor test stand for an long time and a 1:1 scale mock-up was built and tested in the wind tunnel.
