I remember my trip to Goa. The flight was scheduled for six a.m. As the aeroplane taxied on the runway it gained speed. I felt a kick in the stomach and then we were airborne. It was my first flight and I was very excited. My father who was sitting next to me, asked, “Can you tell me how the aircraft flies?”
“Because of wings,” I replied promptly. But I could not tell him what the wings do to make a plane fly.
A simple phenomenon – a grand explanation
Father took a sheet of paper and held it by two parallel ends. The paper drooped from the other side due to its weight. Next, Father blew hard across the top of the paper. Amazingly, the drooping side of the paper suddenly straightened up and seemed to be floating in air. “This is exactly what happens with an aeroplane too,” he said.
“But no one’s blowing air on the aeroplane!” I said. The explanation followed – the aeroplane’s engines push it along the runway at a great speed. It is only when the wind starts rushing past its wings that the plane flies.
Aerodynamics and wing design
An aeroplane’s wing is flat at the bottom and curved at the top. As the wing cuts through the air, the wind either flows along the top or the bottom of the wing.
However, in going over the top of the wing the wind has to travel a longer distance because of the curve. Hence, it also has to travel faster. This creates a low air pressure on the top of the wings.
As the plane gathers speed, this air pressure keeps decreasing. Meanwhile, the higher pressure underneath the wing helps to push it up. That’s how the aircraft gets the required push to rise in the air, just the way it made the paper straighten.
Actually, all flying creatures and flying objects follow the same principle for sailing through the air. The next time I saw an aeroplane in flight, I gave my father a nodding smile, for I knew what flying was all about.