How Do Planes Fly?

Even although I am a total technology geek, there are still some things which I really cannot get my head around. One of those things is air travel. Actually, no, that's not completely true. I can grasp some types of air travel – birds, light weight gliders, helicopters.. the type of air travel I really mean is passenger travel. Jumbo Jets! Big metal tubes weighing thousands of tonnes. How do they stay airborne?

I mean, don't get me wrong. I get the physics and the mechanics and the theory of how an aircraft flies, but if you really consider the reality of it you might just blow your mind! How does something so big and so heavy stay in the air. That's truly a miracle of modern technology if ever I saw one! Think about a brick. If you threw it into the air it would soon plummet back to Earth, yet an aircraft will stay up for hours at a time! Pretty amazing right?

The basic answer to the question 'how do airplanes fly?' is that four different forces are exerted on the craft : lift, weight, thrust and drag. Each of these does it's own part to keep the airplane in the sky. Lift pushes it up and is assisted by the carefully designed shape of the wings. Weight forces the plane back down to Earth and aircraft are designed so that the weight is spread evenly across the craft so it remains balanced. Thrust is the force moving the plane forward and is powered by the engine which helps keep air moving over the wings. Drag is the force that slows the plane down – like walking into a strong wind. When all four forces are exerted on the plane from four directions (up, down, forward, backward) the plane will remain in the air – with a little help from the pilot of course!