Hot Air Ballooning

Hot air ballooning is the activity of flying hot air balloons. Attractive aspects of ballooning include the exceptional quiet, the lack of a feeling of movement, and the bird's-eye view. Since the balloon moves with the wind, the passengers feel absolutely no wind, except for brief periods during the flight when the balloon climbs or descends into air currents of different direction or speed. Most hot air balloon launches are made during the cooler hours of the day, at dawn or two to three hours before sunset. At these times of day, the winds are typically light making for easier launch and landing of the balloon.
Flying at these times also avoids thermals, which are vertical air currents caused by ground heating that make it more difficult to control the balloon. In the extreme, the downdrafts associated with strong thermals can exceed the ability of a balloon to climb and can thus force a balloon into the ground. Before a safe hot air balloon flight can begin, the pilot must check the weather and select a suitable take-off point. The current and forecast weather must have sufficient visibility for the pilot to see and avoid obstructions and sufficiently slow winds to allow take off and landing.
The take-off point must be large enough to lay out and inflate the envelope and clear of obstructions such as power lines and poles, trees, and buildings to allow lift-off under the predicted wind conditions. Finally, the take-off point must be situated such that the predicted winds will move the balloon in the direction of suitable landing sites. Taking off from a location that is directly up wind of a hazard, such as a large body of water, a large metropolitan area, or a large uninterrupted forest, without sufficient fuel to pass over the hazard is not safe.
The next step in a hot air balloon flight is unpacking the balloon from its carrying bag, laying it out on the ground, and connecting it to the basket and burner. A fan is used to blow cold air into the envelope. The cold air partially inflates the balloon to establish its basic shape before the burner flame is aimed into the mouth heating the air inside. A crew member stationed opposite the mouth holds a rope tied to the apex of the envelope. The "crown-man" role is twofold: one is to prevent the envelope from excessive sway, and two is to prevent the envelope from rising before it is sufficiently buoyant. Once the balloon is upright, pilot and passengers climb into the basket. When the pilot is ready for launch, more heat is directed into the envelope and the balloon lifts off.
During the flight, the pilot's only ability to steer the balloon is the ability to climb or descend into wind currents going different directions. Thus, it is important for the pilot to determine what direction the wind is blowing at altitudes other than the balloon's altitude. To do this, the pilot uses a variety of techniques. Pilots are also looking for other visual clues such as flags on flagpoles, smoke coming from chimneys, etc. To determine wind directions above the balloon, the pilot will obtain a weather forecast prior to the flight which includes upper level wind forecasts.