Cool-Ray Hot Air Balloon Team

how a balloon works

Have you ever wondered how exactly Hot-Air Balloons work? Well we have the answer to your questions!

To Understand how Hot-Air balloons work you need to understand the basic principles of the how they fly; and what equipment is part of a balloon. First let's look at some of the pieces that make up a Hot-Air Balloon.

A Hot-Air Balloon is thusly named because it works off the principal that hot-air rises. Since warm air is less dense than cooler air, it rises; thus floating on the top of the cooler air below it. In nature this is known as a convection cycle; the sun heats the earth, the air above the surface heats thus shifting it upward, interestingly enough this is also the natural cause of wind. By artificially heating the air inside the envelope a balloon creates a 'bubble' of hot air inside the envelope. This mass of warm air allows the balloon to become buoyant and rise through the cooler air around it.

Now we are only missing one big piece of the puzzle in our explanation of how balloons work: "How do they get up in the air in the first place?"
The answer to just that question is something we call 'inflation'...might seem pretty obvious huh? Just like a helium balloon we inflate a hot-air balloon, but we don't use a helium tank.

Hot air balloons envelopes are stored in large canvas or nylon bags, to inflate the balloon the envelope is laid out in a long narrow line. Once the envelope is laid out the basket, burner, propane and (for safety) a quick-relase tie-down are all hooked up. The balloon is inflated with cold air on the ground by an inflator fan. An 'inflator fan' is an airplane prop mounted in a cage with a motor attached to force cold air into the mouth of the balloon. It is similar (if not exactly the same) to fans often used by fire fighters to clear buildings of smoke.

To help the fan push air into the balloon two crew members hold open the mouth and hold up the skirt so that air can be blown into the envelope. As you can see the balloon gets quite full on the ground before heat is applied.

To actually rise the balloon into the air, the same principals that allow a balloon to fly are used. The pilot lights the burner and fires a stream of flame into the envelop, heating the air within. As the air temperature increases the balloon become buoyant and rises off the ground.

Once the balloon is up and the pilot has double checked all his connections, instruments, and safety equipment you are ready to take to the sky's!

Have a question or comment about how balloons work? Please don't be shy, send it to us at: We'll be happy to try and answer to the best of our ability.