Hot air balloons are based on a very basic scientific principle: warmer air rises in cooler air.

Essentially, hot air is lighter than cool air because it has less mass per unit of volume. A hot air balloon applies this principle using specially designed equipment.  There is an upper altitude limit, however, since eventually the air becomes so thin that the buoyant force is too weak to lift the balloon. The buoyant force is equal to the weight of air displaced by the balloon, so a larger balloon envelope will generally have a higher upper altitude limit than a smaller balloon.

Modern hot air balloons heat the air by burning propane, the same substance commonly used in outdoor cooking grills. The propane is stored in compressed liquid form, in lightweight cylinders positioned in the balloon basket. The intake hose runs down to the bottom of the cylinder, so it can draw the liquid out.

The Envelope - In most modern hot air balloons, the envelope is constructed from long nylon gores, reinforced with sewn-in webbing. The gores, which extend from the base of the envelope to the crown, comprise of a number of smaller panels. Nylon works very well in balloons because it is lightweight, but it is also fairly sturdy and has a high melting temperature.  As new materials are developed the fabric that are used to make balloons has changed, resulting in lighter, stronger envelops.

Gores and panels - These are the building blocks of the envelope. Small reinforced nylon squares, combine to produce long nylon gores, which extend from the base to the crown.

Scoop - The "Scoop" at the base of the envelope is coated with fire resistant material to keep the flame from igniting the balloon.

Basket - This is the compartment for holding propane and passengers. Pilots usually use wicker because it is sturdy, flexible and relatively lightweight.  However, a ride in a 2 seater chariot is very relaxing.

Burner - Balloons reheat air, and therefore keep rising by using a burner positioned under the envelope. As the air in the balloon cools, the pilot can reheat it by firing the burner. the burner uses propane fuel.  Because the propane is highly compressed in the cylinders, it flows quickly through the hoses to the heating coil. The heating coil is simply a length of steel tubing arranged in a coil around the burner. When the pilot starts up the burner, the propane flows out in liquid form and is ignited by a pilot light. As the flame burns, it heats up the metal in the surrounding tubing. When the tubing becomes hot, it heats the propane flowing through it. This changes the propane from a liquid to a gas, before it is ignited. This gas makes for a more powerful flame and more efficient fuel consumption.

Propane tanks - These hold propane and are carried in the basket or under the seats of the "Chariot".

Parachute - This is an opening at the top of the envelope, which allows air to escape, decreasing the inner air temperature and slowing the hot air balloon's ascent.

Parachute cord - Commonly referred to as the "Red Line" is a cord that allows the pilot to open the parachute top to release excess hot air out of the envelope.

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The Balloonist's Prayer

The winds have welcomed you with softness.

The sun has blessed you with warm hands.

You have flown so high and so well

that God has joined you in laughter and

set you gently back into the loving arms

of Mother Earth.

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