The Helikopter Technik Wagner, formed by Josef Wagner, designed a series of helicopters with coaxial rotors during the 1960s.
The earliest test models were fairly rudimentary machines built to test the concept, and one design was a roadable machine titled the Rotocar. The 2-seater Wagner Rotocar (1960) was developed into the Sky-Trac 4 Aerocar.
All Aero 