Flying Sky Lanterns -how Do They Fly?
While the first hot-air balloon flight took place in 1783, flying sky lanterns, which work on similar principles, have been dotting the skies of Asian nations for more than a millennium. Chinese people have been using these lanterns during festivals and wedding celebrations since a long time. Over time, the aesthetic appeal of these flying lanterns has permeated the western consciousness and such lanterns have found their place in US, UK, Australia and Europe too.
If you have watched the animated Disney movie Tangled, you will recall having seen thousands of such lanterns floating gently above a serene, mirror-like lake. You will be surprised to know that if floated properly, such lanterns can help you replicate such a scene in real life. When I had seen floating lanterns for the first time in my life I was amazed at their beauty. Apart from the obvious and spectacular beauty of these orbs of gliding lights, the question of how they managed to fly intrigued me. Are you too curious about the simple science that propels the paper lanterns skywards?
What makes the Flying Sky Lanterns Fly?
Sky lanterns have become a common sight during festivals and celebrations. No matter where you live, you must have come across these decorative lights. You must have observed that they stay up in the air for about 15-20 minutes. While the name suggests that they fly like a bird, they actually float like a balloon. And the basic principle that makes their flight possible is identical to the one used by hot air balloons. The hot air inside the lanterns is considerably hotter than the air in the surroundings and this air pushes skywards.
The lantern is shaped and built in such a way that the hot air created due to the flame pushes against its top and causes it to ascend from the earth. Just as the fire from the burner of a hot air balloon fills up the balloon with hot air, the heat from the flame on the wick of the lantern pushes hot air towards the roof of the lanterns. This air pushes harder and harder as it heats up and finally the lantern starts moving upwards.
The lanterns slowly float higher and higher. Usually, it takes 1-3 minutes for the lantern to get filled with enough hot air to start floating and drifting. It rises a few hundred feet (the height of ascendance depends on the type of lantern, the material it is made from and also on the fuel used for lighting it) and floats out there for a few minutes. After a few minutes, the wax cell in the lantern burns out and the flame starts dying. As the heat generated from the flame decreases, the lanterns gradually descend towards the ground.
As the lanterns are mostly made from paper, bamboo or synthetic materials that do not weight much, it is not too difficult for them to fly. While the lanterns descend towards the ground, the wick gets extinguished and so there is not any real danger of floating lanterns causing any fires.
If you have watched the animated Disney movie Tangled, you will recall having seen thousands of such lanterns floating gently above a serene, mirror-like lake. You will be surprised to know that if floated properly, such lanterns can help you replicate such a scene in real life. When I had seen floating lanterns for the first time in my life I was amazed at their beauty. Apart from the obvious and spectacular beauty of these orbs of gliding lights, the question of how they managed to fly intrigued me. Are you too curious about the simple science that propels the paper lanterns skywards?
What makes the Flying Sky Lanterns Fly?
Sky lanterns have become a common sight during festivals and celebrations. No matter where you live, you must have come across these decorative lights. You must have observed that they stay up in the air for about 15-20 minutes. While the name suggests that they fly like a bird, they actually float like a balloon. And the basic principle that makes their flight possible is identical to the one used by hot air balloons. The hot air inside the lanterns is considerably hotter than the air in the surroundings and this air pushes skywards.
The lantern is shaped and built in such a way that the hot air created due to the flame pushes against its top and causes it to ascend from the earth. Just as the fire from the burner of a hot air balloon fills up the balloon with hot air, the heat from the flame on the wick of the lantern pushes hot air towards the roof of the lanterns. This air pushes harder and harder as it heats up and finally the lantern starts moving upwards.
The lanterns slowly float higher and higher. Usually, it takes 1-3 minutes for the lantern to get filled with enough hot air to start floating and drifting. It rises a few hundred feet (the height of ascendance depends on the type of lantern, the material it is made from and also on the fuel used for lighting it) and floats out there for a few minutes. After a few minutes, the wax cell in the lantern burns out and the flame starts dying. As the heat generated from the flame decreases, the lanterns gradually descend towards the ground.
As the lanterns are mostly made from paper, bamboo or synthetic materials that do not weight much, it is not too difficult for them to fly. While the lanterns descend towards the ground, the wick gets extinguished and so there is not any real danger of floating lanterns causing any fires.
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