If you have little kids, you know that they ask you four million questions a day.  None of which you seem to have the answer to.  Most of them begin with “How do” or “How does” and since you do not have a college degree in everything, most of the time you're at a loss.  Lucky for you, NASA understands your pain and has created on online storybook for your children to read called “How Do Planes Fly.”  It's at their website.  If you children is too young to read this on their own you can read it to them or at least check it out so that you can get a good idea of how you can break this topic down so that kids can understand it.

                “How Do Planes Fly” is a really cute little illustrated book that your child will love.  If you don't have the time to hunt in down, I'll give you the gist.  “How Do Planes Fly?” starts out by explaining that there are four different forces that keep airplanes in the air.  Those forces are life, drag, thrust and weight.  The shape of the airplane and the way that the air moves around the body of the plane will determine how much lift an airplane has.  Weight must be balanced from the front of the airplane to the back of it; this is what keeps it in the air.  Since weight is a force that pulls us towards the ground, if an airplane isn't balanced, it can't fly.  Thrust is that forward motion, in a sense it is what makes us go.  This is why an airplane has engines.  Drag is the force working against the airplane.  Airplanes must be designed to allow air to pass around them efficiently.  In order for a plane to fly, engineers must design it so that all four of these forces work together to keep it in the air. 

                So now the next time your child asks you about airplanes and how they manage to stay off the ground, you have a good basic jumping off point to help you explain physics to your five year old.  Be warned though, when you answer the question of a child with a reasonable answer, it just leads to them asking another question.  It's an endless circle that you will probably never escape until they turn 30!