How the Balloon Works

Balloons are able to rise into the air on the simple principal that warm air rises. The warm air in the balloon is lighter than the cooler air around it and it has less mass per unit of volume. The actual balloon (which we refer to as the 'envelope' in the business) has to be so large as it takes such a large amount of heated air to lift it off the ground. For example, to lift 450kg worth of weight you would need almost 65,000 cubic feet of heated air! To help keep the balloon in flight the air in the balloon must be continually heated using the burner (see separate section on burners for more information.)

Hot Air Balloons are made up of 3 main parts:

• The Envelope
  The actual fabric balloon which holds the air



• The Burner
  The unit which propels the heat up inside the envelope



• The Basket
  Where the passengers and pilot stand

The burner uses propane gas to heat up the air in the envelope to get the balloon off the ground and into the air. The pilot must regularly fire the burner(s) to maintain a stable flight. As hot air rises very little air is lost through the hole in the bottom of the envelope.

The controls for piloting a balloon are simple....

1 - To move the balloon upwards - the pilot opens up the propane valve which lets the propane flow to the burner which in turn fires the flame up into the envelope. Works in much the same way as a gas grill, the longer you open the valve, the more heat, the faster the balloon rises.

2 - To move the balloon downwards - the 'Parachute Valve' at the very top of the balloon is what is used to bring the balloon down towards the ground. It is essentially a circle of fabric cut out of the top of the envelope which is controlled by a long chord which runs down through the middle of the envelope to the basket. If the pilot wants to bring the balloon down he simply pulls on the chord which will open the valve, letting hot air escape, decreasing the inner air temperature. This cooling of air causes the balloon to slow its ascent. A gentle decent can also be initiated by burning less often as the balloon gradually cools due to heat loss from the warm surface of the balloon.

To navigate to the destination the pilot must catch a wind going in the right direction. The pilot can maneuver horizontally by changing the vertical position of the balloon because the wind blows in different directions at different altitudes. If the pilot wants to move in a particular direction they simply ascend and descend to the appropriate level and ride with the wind. This is however limited to the variation in wind direction on the day which may only be 10 degrees and may not be consistent.