Bruno Nagler and engineer Raoul Hafner together developed 1929/30 the Revoplan R - 1 helicopter. In this patent cyclic and collective rotor adjustment is described for the first time.
Type Single seat experimental helicopter
Engine 1 ABC Scorpion rigid rotor dia. 10 m , 3-bladed
Dimensions Length  , height  ,  span  , wing area   ,
Weights Empty , loaded  , max. take off weight  
Performance Max.. speed  , cruising speed  , range , endurance  , service ceiling   , climb
Type Werk.Nr Registration History
Built in 1929