cycloidal propeller 

 and housing 



personnel sphere 



Scale: 1 in. = 10.0 ft 



Figure 20. Plan view of hydrocopter. 



The principal advantages of the cycloidal propeller over the more 

 conventional variable and fixed pitch, propellers are that the former is 

 capable of thrust modulation (without change in engine rpm) and has the 

 ability to direct the thrust in any direction of the rotor plane. 



Three Voith-Schneider Model 24E cycloidal propellers with a static 

 thrust rating of 20,000 pounds are each powered by a 1 ,000-horsepower 

 horizontal induction motor and will provide lift and lateral thrust. Diagrams 

 for both lift and lateral thrust are shown in Figure 21 . 



84 



