What is the principle of hot air balloon? Please see the expert’s introduction!

When traveling, many people have ridden in a hot air balloon. In many parts of the world, hot air balloons are a very popular entertainment activity. Many people will bring their family or friends to experience it together. Sitting in a hot air balloon and flying in the air, witnessing nature with your own eyes, and letting yourself float in the air will make you feel very relaxed. In fact, the principle of a hot air balloon is very simple. There is a big balloon on top and a heater underneath. Anyone who has studied physics knows that hot air has a lighter density, so it will climb upwards. A large amount of hot air will lift the balloon and keep it suspended in the air. This is the basic principle of a hot air balloon. The following is a detailed introduction to professional knowledge about hot air balloons.

First, the principle of flight

Hot air balloons fly by using heated air or certain gases such as hydrogen or helium, which have a lower density than the air outside the balloon to create buoyancy. Hot air balloons mainly use their own onboard heater to adjust the temperature of the air in the balloon bag, thereby achieving the purpose of controlling the rise and fall of the balloon. The basic principle of hot air balloons is expansion when heated and contraction when cooled. When air expands due to heat, its specific gravity becomes lighter and it rises upwards.

2. Lifting and Flight Principles

Although a hot air balloon is also called an aircraft, it cannot fly as freely as an airplane. The pilot can only control the balloon to change its altitude. The rise and fall of a hot air balloon is related to the temperature inside the sphere. When the temperature inside the sphere is high, the buoyancy of the balloon increases, and the balloon rises; when the air temperature inside the sphere drops, the buoyancy generated by the sphere is less than its own weight, and the balloon begins to fall. The pilot operates the gas switch of the burner in the balloon basket to adjust the temperature inside the airbag at any time, thereby controlling the rise and fall of the balloon.

In addition, there are differences in wind speed and direction at high altitude and low altitude. Near the ground, the wind direction will change and the wind speed will decrease significantly due to the influence of terrain and buildings. If you fly from the ground into the air in the morning or evening, there may be obvious changes in wind direction every few meters or every ten meters, and in some cases the wind direction may even be in the opposite direction. The pilot experiences different wind directions at different altitudes in the air, and then maneuvers the balloon to rise or descend to the altitude with the wind direction he needs and maintain flying in this wind layer, so as to achieve his goal of flying to a certain destination. Simply put, the balloon will fly wherever the wind blows; the faster the wind blows, the faster the balloon can fly.

3. Flight Instructions

time

The best time to fly a hot air balloon is when the sun just rises or one or two hours before it sets, because the wind is usually calm and the airflow is stable at this time. Strong winds and heavy fog are not conducive to the flight of hot air balloons. According to regulations, free flight is allowed only when the wind speed is less than 6 meters per second, the visibility is greater than 1.5 kilometers, and there is no precipitation in the flight airspace.

Place

A flat area of ​​30 meters x 30 meters is required, with no wires or tall buildings around. It is recommended that new students fly under climatic conditions of 4 meters per second. During flight, they should pay attention to maintaining a safe altitude when flying over high-voltage lines, tall buildings, livestock farms, and villages.

equipment

It is best to wear a one-piece cotton flight suit. Passengers are also advised to wear cotton clothes and cotton hats so that they will not stick to the body in the event of a fire.

take off

Flying a hot air balloon requires the joint efforts of a team of people, because the work on the ground is very cumbersome, and it takes at least four people to make a hot air balloon take off. First, spread the balloon on the ground, then connect it to the hanging basket placed aside, use a small blower to blow air into the balloon to make it inflate little by little, and when it is fully expanded, start to ignite. Light a fire to heat the air inside the balloon. The hot air will make the balloon rise to a position perpendicular to the basket. Add a few more big fires and the balloon will take off.