The secret of hot air
Hot air balloons fly because they are filled with hot air. Because hot air rises faster than cold air, the balloon begins to rise. This phenomenon is known as buoyancy, and it is what allows hot air balloons to remain in the air.
Hot air balloons use a burner to heat the air inside the balloon. The burner is usually fueled by liquid propane. The burner mixes fuel with air and ignites the mixture, creating a flare directly below the balloon opening. Once the air inside the balloon begins to heat up, the balloon rises.
The pilot controls the balloon’s altitude, either by heating the air to lift the balloon or by allowing the air to cool to make the balloon descend.
Did you know . . . ?
✔ The invention of the hot air balloon is attributed to the French brothers Joseph and Jacques Montgolfier. One day they placed an open bag of paper and linen on top of a fire, and watched as it rose. This experience prompted them to continue researching.
✔ In 1783, the Montgolfier brothers made a public demonstration before the king and his court. The first passengers of the hot air balloon were a sheep, a duck and a rooster.