Paul Baumgarti was an Austrian who had worked on three helicopter designs during the war years before emigrating to Brazil. He experimented with a number of light helicopters in the 1950s and 1960s including the PB-64 which was an ultra-light single-seater with a minimal tubular fuselage structure. The PB-64 had a pulse-jet propulsion arrangement with the two 13-kg ITA jets fitted to a transverse stabilising beam set at right angles to the rotor. The aircraft had no tail rotor but was fitted with a small rudder. No production of any of these designs was undertaken.