Were going to explain lift. As a plane moves forward the wing deflects air downward. A reaction causes the wing to go up. A commonly asked question is why is a wing titled? Itís tilted to deflect air downwards. The front edge of a wing is higher than the back edge. Itís not just downward deflection of air that causes lift. A specially shaped wing can cause a lot of more lift. Another question is what is the best shape for a wing? A slanted wing or a flat slanted wing is the best shape for a wing. Air flows faster over the top than underneath this increases lift. It does this because the faster moving air has a lower pressure than the slower moving air underneath. If the air doesnít flow smoothly, there is more drag on the aircraft. That slows it down. A helicopter has no fixed wings. A question about helicopters is how does it make its life force? The helicopterís blades push air downwards. This gives it the lift it needs to stay in the air. The blades are shaped and tilted so that they push the air down, just like an airplaneís wings. They can also be tilted to push air backwards and provide thrust as well. Another question is how does a bird stay up in the air? A hawk flaps its wings to prepare to hover. As the wings come down, they push on the air. Then the bird twists its feathers so that they slip easily through the air, just like an airplane. Its wing is the right shapes to give it lift.