64 Miracles Ahead! 



and failed a second time. When the first world war com- 

 menced he turned to the designing of huge land planes. 

 Officials of the War Department remembered the tall blue- 

 eyed young man from Kiev and, disregarding his tender years, 

 ordered the construction of four hundred of his bombing 

 planes. He was then eighteen years old. 



Faith in Sikorsky's designs was engendered not merely by 

 the performance of his model but by his personal history. He 

 had possessed not only a phenomenal mechanical bent as a 

 small child but a remarkable intellectual development. He 

 graduated from college at an age when most youngsters are 

 still in the preparatory grades. At eighteen he was a mature 

 and experienced inventor. Faith in his machines proved jus- 

 tified, for of the four hundred bombers only two were lost 

 during the war! 



When the Revolution of 1917 commenced, Sikorsky came 

 to America and continued to build successful planes. But he 

 had not given up his idea for a direct-lift machine. In 1939 his 

 helicopter flew. By 1943 he had made eighteen major changes 

 in the craft. The first helicopter carried three forty-six-inch 

 radius propellers at the tail for control. All three propellers 

 had variable-pitch blades controllable by the stick in the 

 cockpit of the craft. In 1941 the main rotor was changed so 

 that the pitch of the individual blades could be varied as they 

 passed each side of the ship. Additional work resulted in a 

 refinement of the main rotor so that the pitch of the individ- 

 ual blades could be varied throughout its entire circuit. Each 

 blade can, for example, be made to decrease pitch as it passes 

 the front of the ship and to increase pitch as it passes over 

 the tail. This tilts the rotor forward and causes the ship to 

 move forward. The brilliant engineering work on the main 

 rotor permitted Sikorsky to eliminate two of the propellers 

 on the tail of his ship. Only one rotor in addition to the main 

 one is needed, and it faces sideways at the tail to act as a rud- 



