In the open space outside the Research Center, a large helicopter is being towed out of the hangar by a tractor.
This helicopter's design is vastly different from a regular helicopter because a normal helicopter only has one rotor, whereas this helicopter has two large rotors.
Moreover, these two large rotors are not placed on the sides of the fuselage or at the front and rear ends like some dual-rotor aircraft; instead, they are positioned on top of the fuselage, forming a slanted cross.
This type of helicopter is called a coaxial rotor helicopter, and internationally, only a minimal number of helicopters use this design.
Its rotors have been specially adjusted and designed; although their trajectories interfere with each other while rotating, they do not collide.
This design can enhance the helicopter's load capacity and stability, although it does reduce the flexibility of this dual-rotor helicopter.
