Airplanes are machines that can fly with engine or propeller power. They are able to use aerodynamics (how air and objects move) to fly. Airplanes make it so that we can travel around the world in just a few hours! Airplanes can coke in all shapes and sizes like the tiny airplanes that you see at stunt shows, to big passenger airplanes! The shape of an airplane’s wing is very special. It is called an airfoil. Airfoils are a curved piece of aluminum or other metal. As the airplane flies, the warm air goes above the airfoil and the cold air goes under the airfoil. The cold air is heavier than the warm air, so it keeps the airplane from crashing to the ground! That is called lift. Propellers or plane engines propel the airplane forward. That is called thrust. Helicopters are vehicles that can land and take off vertically. They can hover in place. That is a very unique skill. Helicopters do that by having sets of blades. The blades on the top circulate air to make the helicopter take-off vertically. The blades on the tail are for steering. That is also thrust. Helicopters and airplanes are difference because airplanes need a runway to take off, but helicopters can just take off vertically or straight up.