Question

why helicopter has two propellers​

Answer 1

Explanation:

Have you ever thought why some helicopters have two propellers? The main rotor creates lift by re-directing the flow of air downward. ... Therefore torque tends to turn the aircraft in one way and the tail rotor's thrust opposes this. To turn the helicopter in the opposite way, the tail rotor thrust is reduced

Answer 2

Answer:

because with 1 propeller the helicopter would spin the apposite way until the propeller hit full speed and then once off the ground it would only fly in a circular motion  

Explanation: