Helicopters: How They Work
Helicopters are the most maneuverable aircraft in the sky. No other flying machine can hover in place, fly backward, rotate completely, around, and move to the side as well as forward. Its amazing versatility makes the helicopter a crucial aircraft for rescue, military, and law enforcement.
To understand how helicopters work, take a look at the wings. The blades of a helicopter are wide in the front and narrow at the back. This tapered shape forces air beneath, giving the vehicle lift.
Airplane wings are shaped the same way. The difference is that planes have to keep moving forward to keep the air moving under the wings, and to keep the plane up. Helicopters rotate their blades continuously, so the helicopter does not have to move forward to generate lift.
A helicopter’s main propeller is called a rotor. It’s got one rotor on the top of the cabin, and a smaller secondary one on the tail. The tail rotor is there to stabilize the craft when the main rotor is spinning. If it wasn’t there, the force of the main rotor’s rotation would spin the entire helicopter—not just the blades. The tail rotor pushes the helicopter in the opposite direction from the main rotor’s spin force, keeping it stable.
A helicopter pilot uses both hands and both feet to guide the craft. One hand moves the copter right, left, forward, and backward on the “cyclic.” The other hand operates the “collective,” which controls vertical movement and engine speed. Both feet control pedals that manipulate the tail rotor, which can make the helicopter spin in a circle.
Helicopters have four main rotor blades. The angles on the blades can be changed both in tandem and individually. This controls both vertical and horizontal movement of the aircraft. The tail rotor can spin the helicopter around in a circle. Its rotor blades are also adjustable, and changes in their angles allow the helicopter to make quick turns.
No other aircraft can hover like a helicopter. To pull it off, a helicopter pilot uses the cyclic to maintain the craft over a single point on the ground, the collective to keep the altitude steady, and the foot pedals to keep the nose facing the right way. It’s a maneuver that grows difficult—even dangerous—during windy weather.
Helicopters have an astonishing range of movement—no other aircraft can replicate their movements. This is why they’re so important to wilderness rescue operations, disaster evacuations, military and law enforcement operations, and many other crucial functions. They may be the most versatile—and useful—aircraft ever invented.