What Is The Temperature Of The Air In The Crown Of a Hot Air Balloon?

The air inside of a hot air balloon can get pretty hot, hence its name and this air must maintain its temperature since it’s what helps the balloon to rise upwards.

On average, at the crown of a hot air balloon, the temperature will be about 100 degrees, the range however can differ according to the shape and size of a balloon, but around 100-degrees is important for the balloon to stay afloat.

We’ve composed a guide below which will cover what temperature a hot air balloon should be, why this is important, lift force and what happens if the temperature becomes too hot or cool.

What Temperature Should a Hot Air Balloon Be?

Most hot air balloons should have a crown temperature of 100-degrees but this can vary according to the type of balloon and its shape, as well as the outdoor temperature. The temperature of a hot air balloon’s crown can change during the flight but should be maintained and manipulated by the pilot for flying.

Why Does Hot Air Make Hot Air Balloons Rise?

To understand why the crown of the hot air balloon is so hot, we need to know why hot air makes a balloon rise, to begin with.

To put it in simple terms, hot air helps a hot air balloon to rise since it is lighter than the cold air on the outside or less dense. Since hot air rises through convection it pushes the hot air balloon upwards and causes it to float through buoyancy.

If the air inside was to drop in temperature then the hot air would become less dense, causing the balloon to sink rather than float.

Why Temperature & Lift Force Are Related In a Hot Air Balloon?

As we touched on above, the hot temperature allows a hot air balloon to lift or float, different temperatures however will have a different lift force.

The lift force of a hot air balloon can be determined by the density difference in the air between the inside air and outside air as well as volume, which is influenced by temperature, since the higher the temp, the less density and more volume it takes up in the balloon, causing it to expand in size.

For example, let’s follow this calculation for a lifting force down below; if a hot air balloon has a volume of 10m3 and becomes heated to 100-degrees by the burner and the outdoor temperature was 20-degrees then the air density inside would be 0.900kg while the density outside would be 1.2kg.

The force can now be calculated as 25.4N, this is then divided by the mass of 9.8 m/s making it a lifting force weight of 2.6kg.

What Happens If Temperature Falls In a Hot Air Balloon?

If the temperature does fall inside of a hot air balloon then the hot air balloon will fall since it becomes heavier, this is because the particles stop moving around and the density increases as the air become cooler.

As a pilot will be to increase the burner and lower it they can change how high and low the hot air balloon goes.

Is It Hot Inside a Hot Air Balloon?

Many people assume that they will be very cold in a hot air balloon since they leave in the early hours of the morning and the latitude is high, meaning colder temperatures. You should not forget however that the top of the balloon is heating up to 100-degrees, so you will become very warm.

Could a Hot Air Balloon Become Too Hot?

It is unlikely that a hot air balloon can become too hot since they have temperature regulators inside of them which will show if the balloon is becoming too hot. Most of the time hot air balloons are flow early in the morning when the temperature outside is not too hot or cold, if the temperature is too hot outside then the flight will likely be cancelled.

Frequently Asked Questions About Crown Temperatures & Hot Air Balloons

Why does the crown of a hot air balloon become so hot? 

Through convection, heat rises, which is why the top of a hot air balloon is so hot compared to the bottom, this makes the balloon very toasty as a passenger, so remember to wear removable layers!

How does temperature affect a hot air balloon? 

Temperature affects hot air balloons in many ways, the hotter the outside, the hotter the balloon needs to be on the inside, the temperature also has to be maintained for the balloon to be able to fly.

Can a balloon become damaged from the heat?

Yes, if a balloon becomes too hot because it is too hot outside then it can become damaged from excess heat, on average the crow should stay around 100 degrees.

How is a balloon heated?

Balloons are heated by the propane gas burner in the bottom of the balloon’s basket, this could be multiple burners, not just one, they can be controlled to take off, float and land the balloon.

Last Words

Overall, the crown of a hot air balloon is around 100 degrees in temperature, but it can change according to the size and shape of the balloon, the temperature is very important since it’s what makes the hot balloon rise, cool air lowers a balloon and hot air helps it rise.