Helicopters




Helicopters can fly straight up. They can fly forward, sideways, and backward. They can even hover in one place. An airplane must speed down a long runway to take off and land. Wings hold an airplane in the air. Helicopters do not need runways, and they do not have wings.

WHAT HOLDS A HELICOPTER IN THE AIR?

Big blades on top of a helicopter keep it in the air. The blades are a little like fan blades. The blades spin very fast. Wind blowing down from the whirling blades holds a helicopter up. The blades also control the direction in which the helicopter flies.

The blades make a loud chop-chop-chop noise as they turn. The noise caused people to nickname helicopters “choppers.”

Helicopters cannot fly as fast as an airplane. The fastest helicopters go about 200 miles per hour (320 kilometers per hour). They also cannot go as far as an airplane. Helicopters burn a lot of fuel.

HOW MANY BLADES DO HELICOPTERS HAVE?

The blades of a helicopter are called the rotor. Some rotors have two blades. Some rotors have three or four blades. Some big helicopters have rotors with eight blades. Big helicopters sometimes have two rotors on top.

A long metal tail sticks out from the back of most helicopters. These helicopters have a small rotor on the tail. The tail rotor blows air sideways instead of down. It helps the helicopter steer.

HOW DO YOU FLY A HELICOPTER?

A helicopter has a cockpit just like an airplane. The controls are in the cockpit. A helicopter has two control sticks, or levers. It has two pedals on the floor.

When you’re flying a helicopter, you push or pull on the stick on your left side to make the blades tilt. Tilting the blades makes the helicopter go up or down. A grip on this stick controls the speed. You twist the grip to make the helicopter go faster or slower.

The other lever is between your knees. You move this stick around to make the helicopter fly forward, backward, or sideways.

The pedals on the floor control the tail rotor. You step on the pedals to turn the helicopter. Pushing the left pedal makes the helicopter turn left. Pushing the right pedal makes the helicopter turn right.

HOW DO WE USE HELICOPTERS?

Helicopters can go places that are hard to reach. They can go places where airplanes cannot land, or where there are no roads for cars or trucks.

Helicopters can rush injured people from a car accident to a hospital. They can rescue people from the tops of burning buildings. They can pluck them from trees in the middle of raging floods. They can lift people from the decks of sinking ships at sea.

Military helicopters are important in war. They carry troops to battle. They carry wounded soldiers to hospitals. They can even shoot missiles.

Helicopters do other kinds of work. Reporters can fly in helicopters to cover news stories. Police use helicopters to chase suspected criminals. Farmers can use helicopters to spray their fields. Sometimes helicopters work on construction. The carry heavy parts to the tops of buildings.

WHO INVENTED THE HELICOPTER?

People imagined machines like helicopters hundreds of years ago. The ancient Chinese made a spinning top that could rise up into the air. The Italian artist and inventor Leonardo da Vinci drew a design for a machine like a helicopter in 1480.

The first helicopters flew in France in 1907. They were hard to control. People kept trying to build better helicopters. Finally, a Russian-born American engineer named Igor Sikorsky made a workable helicopter. It was the first helicopter with a tail rotor. He flew this helicopter in 1939. Most helicopters today are like the helicopter that Sikorsky built. Inventors and engineers are still working to make bigger and better helicopters.







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