Autorotation (helicopter)

When a helicopter's engine suddenly stops working, it's like when your toy car runs out of batteries. But unlike your toy car, a helicopter has something called "autorotation" that helps it land safely even without power.

Let's say the helicopter is flying in the air with its blades spinning. Suddenly, the engine stops working and the blades stop spinning as well. This is called a "dead engine."

Now, the weight of the helicopter starts pulling it towards the ground. But the blades, which are like wings, are still there to provide lift. So, when the helicopter is falling through the air, the blades start automatically spinning because of the air rushing up from the ground.

This spinning motion of the blades causes them to create lift, which slows down the helicopter's descent, just like how a parachute slows you down when you jump off a high place.

The pilot can also control the direction of the helicopter during autorotation using the tail rotor, which works like a rudder on a boat. The pilot can steer the helicopter to a safe landing spot, like a flat area or a clearing.

So, just like how you can still glide your toy car down a ramp even when its battery is dead, a helicopter can still safely land using autorotation when its engine fails.