Basic Principle

Air becomes lighter when it is heated. When the air in the balloon is hotter than the outside air it will rise. The lighter hot air provides buoyancy, which enables flight A hot air balloon comprises an envelope, basket, and burner. The average balloon has a volume of approx. 2,000cu Metres and is approx. 17 metres in diameter and 24 metres high, It weighs between 200-250 kilograms. The balloon has a vent at the top for adjusting buoyancy through the partial release hot air. The balloon is also equipped with an Altimeter, Variometer, GPS, UHF Radio and Airband radios.

Components

 Envelope

The envelope is the technical name for the colourful part of the balloon. Other than the heat-resistant fabric for the aperture at the lower end, balloons are made of synthetic fibres such as nylon and polyester. These fabrics are treated with a very thin heat retaining coating to stop the air escaping. The envelope is shaped like an inverted light bulb with a more stylish appearance, this shape allows the greatest buoyancy with a smaller surface area. The air inside the envelope reaches 100 degrees Celsius or hotter during flight. When fully inflated the balloon holds its shape by internal pressure. This pressure is so strong that it is possible to walk on the top of the balloon, just watch out for the burnt toes!

Burner

The burner is the engine of the balloon. The burner is not always switched on, rather, it is turned on and off during flight. It is switched on for longer periods when ascending and switched off for longer periods when descending. For example, a burner will be switched on for five seconds and switched off for five seconds when ascending, and switched on for five seconds and switched off for 10 seconds during horizontal flight. When descending, the burner is switched on for five seconds and switched off for 15 seconds.The burner uses standard LPG which is held in tanks carried inside the basket. An average balloon can fly for between 2 and 3 hours before needing to be refueled.

Basket

The basket is the section of the balloon where the pilot and passengers ride. It is made of wicker (cane), because it flexes with the stresses during landing and absorbs the shock of landing. Most baskets are square, although some can be triangular. A basket for a balloon with a crew of three or four people is one meter deep, 1.2 meters wide, and one meter high. The basket is loaded with four 20-kilogram tanks of liquid propane gas, enabling a flight of 2-3 hours

How do you steer a balloon?

Technically, you cannot steer a balloon, it drifts with the wind. An experienced pilot can control the direction of flight very accurately by either ascending or descending. This is due to the fact that wind direction does not remain in the same direction as you climb. In some cases the wind direction can be 180 degrees opposite in as little 50 metres of height. Using these different winds it is possible to be quite accurate in the directional control of the balloon.

Airworthiness

Balloons must be inspected for airworthiness every year or every 100 hours of flight time. Many factors impact the life of a balloon, including type of fabric, maintenance and conditions under which it is flown. Generally, balloons with more than 500 hours are considered old, but may still be airworthy if properly maintained.

Cost

New balloons start at around $35,000 for the basic system. Balloons for commercial operations with custom features can drive the price much higher, with some special-shape designs costing upwards of $100,000. It is possible to find good second hand balloons, but these do not come onto the market often and sell quite quickly. A good second hand balloon can cost between $10,000 and $20,000. Do not buy a second hand balloon without through research and before talking to at least two different people about the balloon. Your life depends on it!