Gila and Salt River Base and Meridian Hot Air Balloon and Airship Ascension Social Society, Inc.
Established 1975 as the
Arizona Balloon Club
Steering a balloon.
We can't change the wind...
...but we can change our altitude and we can change our launch site.
Working the winds takes knowledge and experience...
...and it is one of the great joys of the sport.
Weather Briefing - click here;
Working the winds starts with a detailed weather briefing.
There are many, many weather websites including Blast Valve and Weather Underground where a pilot can learn wind direction and speed.
Pilots will also telephone Flight Service at 1-800-WX BRIEF (992-7433) for additional information such as turbulance warnings or temporary flight restrictions (TFRs) such as when the President comes to town.
Pibal - click here;
A pibal, short for pilot balloon, is a helium filled toy balloon that is
released before each flight.
Pibals ascend at between 250 and 300 feet per minute...
...so a pilot can estimate the direction and speed of local winds and plan the flight accordingly.
Effects of Terrain - click here;
Air, like water, flows downhill. In Phoenix the colder air from the
high country to the northeast sinks so the prevailing wind during
the fall, winter, and spring are out of the east.
In Albuquerque this phenomenon is so consistant it sets up what is called the "Albuquerque Box." The launch site for the Albuquerque International Balloon Fiesta (AIBF) is within a half mile of the Rio Grande River which flows south from the high country near Santa Fe and Taos. At launch the balloons will ride the drainage wind to the south. When they go up a couple of hundred feet they will reverse direction and fly back over the launch field. Then they can drop down and head south again.
It is quite and experience to watch the balloons work the winds during competitive events at the AIBF. The pilots, who are the best in the world, will work the winds to make three, four, or even five passes over the field as they navigate their way to the targets.
The Effect of the Sun - click here;
The sun heats the earth unevenly. The east side of a mountain will heat up more quickly in the morning than the surrounding terrain causing that air to rise. Winds in the valley will flow west to fill the vacuum.
More Effects of the Sun - click here;
Another example is flying over brown and green fields.
The sun doesn't heat
the air. It heats the ground which, in turn, transfers the heat to the
air above. The ambient tempreature above a brown, unplanted field
will be warmer so the relative difference between the temperature inside
and outside the balloon will be less and the balloon will descent.
The opposite is true for a green, planted field. The ambient temperature is lower and the balloon will ascend.
Head on a Swivel - click here;
Balloon pilots watch trees, smoke, and other balloons to continually update their estimate of wind speed and direction.