Austrian jumper Felix Baumgartner may soon be setting a record by jumping 23 miles down from a stratospheric balloon. This balloon jump would make him the first person to descend in free-fall at the speed of sound.
Stratospheric balloons are filled with helium. Baumgartner’s balloon, the Red Bull Stratos, is an impressive 55 stories high and holds 30 million cubic feet of helium. Technology has come a long way since the invention of the hot air balloon.
Hot Air History
September of 1783 saw the very first hot air balloon, invented and launched by French scientist Pilatre de Rozier. He placed a rooster, a duck and a sheep inside his creation and kept them airborne for approximately fifteen minutes.
The first balloon to carry human passengers lifted off two months later in Paris. This trip was more successful, with a twenty-minute flight and a gentle landing.
Innovations continued at a fairly regular pace until 1935, when a balloon soared to 72,395 feet. This set a record that would stand for twenty years. The flight carried a pressurized chamber which allowed its passenger to survive in such high altitudes. This flight is very significant because it paved the way for different types of aviation and space travel.
Hot Air Mechanics
Hot air balloons operate on a very simple principle of science – hot air is lighter than cool air. By heating the air trapped inside a balloon, the balloon itself becomes buoyant and, if enough air is used, able to carry heavy loads.
Construction of hot air balloons hasn’t changed much over the years. A source of fuel – typically tanks of compressed propane – are attached to the interior of a balloon’s basket. These tanks are connected to a long, coiled metal tube which acts as a burner, situated at the bottom of the balloon. The balloon operator lights the burner and turns a valve to open the tanks. The pressurized propane shoots out, turns from a liquid into a gas, and is burned by the heated metal coil. By lighting the burners during a flight, a balloon operator can keep the balloon airborne for longer periods of time.
Burners are also responsible for how high a balloon soars. By increasing the heated air within the balloon, the operator can take it higher. When it’s time to land, the operator pulls a cord connected to a parachute flap at the very top of the balloon. This flap opens and releases heated air, causing the balloon to sink.
In many balloons, there is a second valve which allows liquid propane to be burned. This is primarily used when flying over a farm or ranch. When propane is burned in gas form, the resulting sound is extremely loud, and this noise often frightens domestic animals.
Although hot air definitely has lifting power, it’s not very strong. This is why hot air balloons are so large – they have to be in order to carry the weight of their equipment, operator and passengers. Sixty-five thousand cubic feet of hot air can lift approximately one thousand pounds.
You’ve probably noticed that hot air balloon baskets are made of wicker. This isn’t just for appearances – wicker is the very light and very strong. It also flexes slightly, which makes for a much softer landing. A completely rigid basket would bounce more sharply, because it wouldn’t ‘give’ upon impact. Wicker baskets absorb most of the impact, so passengers don’t feel a hard jolt as they come back down to earth.
Why We Love Hot Air Balloons
It’s not hard to imagine why we’ve been in love with hot air balloons since their invention. There’s no other way to experience flight in such a peaceful manner. You can really appreciate beauty of our world when viewing it from such heights, and that view is leisurely and serene. Jets are great for quick travel and paragliding is thrilling, but for a relaxing aerial experience, you can’t beat a hot air balloon ride.
Make a Hot Air Balloon
You can make a hot air balloon from tissue paper. It won’t be strong enough to carry a load, but it will be light enough to fly. For instructions on how to make the balloon, watch this video.