Why Can’t Humans Fly?

Key concepts – gravity, weight, body and bone structure, flightless birds and the reason behind it

You might have heard the phrase “free as a bird”. Why birds are free? The answer is simple, they have wings and can fly. They can move from one tree to another whenever they want just by stroking their wings. They can fly high in the sky. Birds have the ability to touch the sky.

Flying high in the sky has always been a dream of humans but unfortunately we can’t because Nature has provided different species with different features and humans are not provided with the ability to fly. There are so many factors which doesn’t allow humans to fly like gravity, weight and body structure. Let’s try to understand these factors deeply.



Gravity is one of the most important reason why humans can’t fly. Gravity is something which holds everything on earth. Gravity is a force present in the core of earth which attracts everything towards downwards. Due to gravity we are able to walk properly on earth.

Everything on earth have weight, or downward force of gravity proportional to their mass. humans can’t fly because of gravity as humans have more mass as compared to birds so downward gravitational force is more on humans and doesn’t allow humans to fly.


Weight is one of the major factor why humans can’t fly. Bird’s wingspan and wing’s muscle strength is balanced with its body size. Birds have much smaller body as compared to humans thus have very light body, light skeleton and hollow bones which puts very light pressure on their wings.

On the other hand humans don’t have wings and our body is too heavy to fly even if we attach wings. This is the reason why some of the birds who have wings but still cannot fly because of their weight like ostrich, penguin and rhea.

Body structure

The most important thing required to fly is wings and humans don’t have wings. Our body structure is not made to support flying. Even if we attach wings to our arm it should be at least 80 feet long and strong as well to make a human fly but still it is nearly impossible. Birds have wings which is balanced with their body. Their body is very light and thus allow them to fly.

Humans are the most important animal on earth. Humans have the ability to make their dreams come true. Humans discovered many unbelievable things on earth and invented unexpected things which made our life and survival on this planet very easy.

But, Humans can fly?

Though human body structure don’t allow humans to fly but it cannot stop human’s mind to fly. The dream of humans to fly came to life on December 17, 1903 when aeroplane was invented by Wright brothers. Humans are able to fly not by attaching wings to their arms but by attaching wings to a flying machine. Now thousands of people can fly at a time in an aeroplane and many such inventions like helicopter, parachute and hot air balloon.


Everyone is born with some unique features and humans are the most unique creature on this planet. Humans are born with an incredible mind. Birds fly with their wings but humans fly with their machines which is a result of their incredible intelligence. Various factors like gravity, weight and body structure resisted humans from flying but human’s will power made its dream to fly possible through aeroplanes, helicopters, parachute etc. Human can make anything possible, From aeroplanes to fly in the sky to submarines to sink in the depth of oceans. If birds are able to fly then humans have ability to put life to their dreams.

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