Hot Air Balloon

One of the oldest and most fundamental elements of aviation history, hot air balloons are typically air vehicles that can take off by being filled with heated air or lighter-than-air gases (such as helium or hydrogen), usually with a basket. Balloons have been developed as a result of humanity's centuries-long fascination with the sky and are now primarily used for hobbies, tourism, and scientific research.

^{Hor Air Balloons}

The foundations of the hot air balloon date back to the scientific studies on gases in the 17th century. While Evangelista Torricelli conducted one of the first studies on the atmosphere and gases, Robert Boyle discovered that hydrogen was the lightest gas. In 1766, Henry Cavendish contributed to the balloon concept by discovering that hydrogen was 14 times lighter than air.

The Montgolfier Brothers made the first successful balloon flight using hot air in 1783. Joseph Montgolfier observed that the hot air rising from the chimney while drying clothes was lighter and ascended. As a result, they made a balloon from waxed paper and silk and successfully flew an unmanned balloon on June 5, 1783. On September 19 of the same year, the first live flight was made, carrying a chicken, a duck, and a sheep.

On November 21, 1783, Jean-François Pilâtre de Rozier and Marquis d'Arlandes made the first manned balloon flight in history, taking off from Paris with a balloon created by the Montgolfier Brothers. Around the same time, Jacques Charles discovered that hydrogen gas had a more effective buoyancy capacity than hot air, leading to the development of hydrogen balloons.

^{Jean-François Pilâtre de Rozier - First Flight Depiction}

In 1785, a balloon flight took place in the presence of the Ottoman Sultan. The balloon took off from Istanbul and landed in Bursa, 120 km away. These experiments demonstrate the Ottoman Empire's interest in aviation history.

In 1819, France introduced legal regulations to reduce air traffic complexity caused by uncontrolled balloon flights. Today, commercial and recreational ballooning activities are licensed and regulated by various aviation authorities.

Hot air balloons are made up of three main components:

The canopy of the balloon is typically made from tear-resistant nylon or polyester material. The lower part of the canopy uses fire-resistant materials like Nomex. This feature prevents the fabric from being damaged when the burner is operating.

Baskets are usually made from wicker and reinforced with steel wires. They carry the passengers, the pilot, and the propane fuel tanks. Wicker is preferred for its lightness, flexibility, and durability.

The burner is a system that converts liquid propane into gas and burns it. It is positioned above the pilot and passengers in the basket, and it functions by heating the air inside the balloon to provide lift.

^{Hot Air Balloon Structure}

The flight of balloons relies on Archimedes' principle of buoyancy. However, to understand the working principle of hot air balloons, a more detailed explanation is needed:

An object rises if it is lighter than the surrounding environment. When the air inside the balloon is heated with the help of the burner, it expands and its density decreases. This makes the balloon lighter than the surrounding cold air, and as the balloon rises, it continues to ascend until the surrounding air density stabilizes.

The burner creates a large flame by burning liquid propane.

This flame heats the air inside the canopy, causing it to expand.

The expanding air loses its density and rises, which allows the balloon to lift off.

The pilot controls the balloon's ascent and speed as follows:

• To rise: The pilot ignites the burner to heat the air further.
• To descend: The pilot pulls the valve at the top, allowing the hot air to escape from the canopy.

Hot air balloons move according to the direction of the wind. The pilot can partially change the direction of the balloon by using wind currents that blow in different directions at different altitudes. However, complete control is not possible.

Early mornings and late evenings, when winds are calm, are the best times for balloon flights. These conditions provide a balanced flight and smooth landing.

Balloons move according to the wind's direction and strength. The pilot has limited control over the direction of the balloon; by changing the balloon's altitude, the pilot can take advantage of wind currents blowing in different directions. The best times for flights are early mornings and late evenings, when the air is calm and favorable for flight.

Hot air balloons are now primarily used for commercial and recreational activities. Aviation authorities in various countries regulate and monitor these activities by issuing licenses. In Turkey, these activities are managed by the General Directorate of Civil Aviation.