In 1944, American inventor Stanley Hiller, Jr. made the first helicopter with all metal rotorblades that were very stiff. They allowed helicopter to fly at speeds much faster than before. In 1949, Stanley Hiller piloted the first helicopter flight across the United States, flying a helicopter that he invented called the Hiller 360.
In 1946, Arthur Young of the Bell Aircraft company, designed the Bell Model 47 helicopter, the first helicopter to have a full bubble canopy.