However, the Sikorsky YR-4B wasn't the only helicopter to make its debut in World War 2. Let's take a closer look ... the Flettner used intermeshing rotors (two rotors that turn in opposite ...

There's no main rotor on the helicopter and the tail boom was also gone, and it's just a vessel at that point with no direction." Chopper 2 is the same model helicopter as the one that plunged ...

ABOVE: Sikorsky’s VTOL prototype successfully demonstrated stability and manoeuvrability in both helicopter and aeroplane ...

The Bell 206 sightseeing helicopter departed a downtown Manhattan heliport at 2:59 p.m. and the ride lasted less than 20 minutes. Eyewitness video showed the rotors and the fuselage separating ...