From the hallway to the sky, another post on flight today. Hot air balloons are generally credited with being the first aircraft, although that’s probably Eurocentric – there are earlier reports of people flying on kites in Asia. The difference is that kites are tethered and can only lift you, whereas a balloon can take you somewhere else.
Hot air balloons probably began as signal lanterns in Asia, the light meant they could be seen and a paper balloon would carry them up. The first recorded manned flight was in 1783 in France in a balloon built by the Montgolfier brothers, and a few weeks later it was used in the first untethered or free flight. Modern balloons are usually pushed by the winds, although airships have their own propellers.
How they work
Hot air balloons use hot air for buoyancy. Pretty obvious. They have a large envelope or balloon that is open at the bottom with a heat source, today itis generally a burner with an open flame. Heating gas gives it energy and makes the molecules zip around faster, which moves them further apart. Think about a group of people running, they move further apart than people who are walking or standing still. This is what blows the balloon up – the particles whizzing faster and pushing it out.
It means that the hot gas, contained inside the balloon, has less actual particles taking up the same space so it is lighter. Light things don’t rise so much as the denser, heavier air around them is pulled down and they are pushed up out of the way.
Ballooning is mainly for recreation. Some balloons are made in fantastic shapes and there are specialist balloons built to compete for records in distance, altitude and endurance, but the majority are built to take pilots and tourists up and show them another view of our world.
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