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 single-seat PB-60 unpowered ground-towed rotor kite, and the PB-64 which was an ultra-light single-seater with a minimal tubular fuselage structure. No production of any of these designs was undertaken.

R.Simpson "Airlife's Helicopter and Rotorcraft", 1998