CELEBRATING 50 YEARS HOW A GAS BALLOON WORKS By Kim Vesely Adapted from the 2007 Balloon Fiesta program he gas balloons used in the America’s Challenge are in some ways similar to, and in others very different from, the hot air balloons spectators see during most of the Albuquerque International Balloon Fiesta. TLike hot air balloons, gas balloons have an envelope, or gas cell, to hold the lifting gas that keeps the balloon aloft. The balloon also has a basket or gondola which holds the passengers and everything they need to navigate and survive for two or three days aloft. The basket is most frequently made of wicker, but in order to save weight some teams build lightweight baskets using aluminum or composite frames and fabric panels. Distance gas ballooning is a sport where every ounce can make a difference in how long and far the balloon flies. For lift, gas balloons use hydrogen, helium or other Above: Four-time champion Peter Cuneo launches in the gases that are lighter than ambient air in their natural, 2017 America’s Challenge. Note the maneuvering and de- unheated state. Almost all gas balloons today use flation lines attached to the load ring, the sandbags (blue) hydrogen, as helium has become prohibitively scarce and and gear tied to the side of the basket, and the trail rope expensive. The balloon systems are conductive in order used during landing. Photo by Missi Leonard. to disperse any static electricity that might develop and spark a fire. Gas balloon envelopes are made of non-porous balloons by going up and down to find winds going in materials to keep the loss of gas to a minimum. The the direction they want to go. But in gas balloons, teams balloon is attached to a circular load ring via a series of must fly several days with only the resources they launch ropes or cords, or on some models load tapes that are with – they can’t land at the nearest 7-11 for gas, snacks, similar to those found on hot-air balloons. The envelope and bathroom breaks! So they use the natural heating and load ring are then attached to the basket by a series and cooling cycles that occur every day to maneuver. of ropes and toggles or carabiners. In the morning, when the sun comes up, it heats Just as with any type of balloon, pilots “steer” gas the gas inside the balloon. As the gas gets warmer it ® 194 Albuquerque International Balloon Fiesta