Why does helicopter flies slantingly?

Answer 1

It's in the basic principles of how helicopters actually work. The spinning rotor blades provide upwards or downwards thrust only (excepting the anti-rudder torque action). So to go forwards the spinning rotor disc is pulled down in the direction of the font on the aircraft, to an angle where the usual upwards motion turns into partial forward motion. You want to move faster or quicker, just pull the rotor disc down further in front of you. This is all done mechanically through a swashplate. These kind of movements are done constantly by the pilot just to keep hovering in one place or even wind correction.

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