How Do Hot Air Balloons Work?
People often wonder how hot air balloons work. The question often arises when people are thinking of taking a hot air balloon ride for the first time, or when they see a balloon scudding across the sky. It's natural curiosity to ask "how do hot air balloons work?"
Actually, the secret behind how hot air balloons work is really very simple. A hot air balloon takes advantage of the fact that warm air rises. Creating a pocket of air inside the balloon which is warmer than the surrounding air is all that it takes to cause a balloon to take flight.
Modern hot air balloons use propane fuel (the same thing that is used in outdoor barbecue grills) to heat the air inside the balloon by means of one or more burners, which are attached atop the basket. Compressed liquid propane is stored in light weight cylinders located in the balloon basket. A hose then connects the propane cylinders to the burners.
Propane travels through the hose to the heating coil, which is made from steel tubing coiled around a burner. When the burner is lit, the liquid propane is drawn out and ignited. The resulting fire heats the metal tubing, and the propane inside, changing it to a gaseous state in which it burns with a strong and fuel-efficient flame.
When the hot air balloon pilot opens the valve and fires the burner, it creates heat, and the balloon rises as the air inside it is warmed. The balloon itself is made of sturdy fireproof material so that the fire that is used to power the balloon doesn't ignite the balloon itself.
Most passenger compartments are made from wicker, the same lightweight, durable and flexible material that patio furniture is often made from. In addition to be being durable, wicker also does a good job of absorbing some of the impact upon landing, so passengers feel less of a jolt when the balloon sets down.
Even though hot air balloon design is simple, it takes expertise and skill to pilot one. The pilot is able to go higher and faster by using a larger (i.e., hotter) flame as compared to a smaller one. Some hot air balloons have multiple valves so that the pilot can choose to burn propane fuel as either a gas or a liquid, and some are equipped with as many as four burners.
The pilot also has a cord that he or she pulls to open what is called the parachute valve. When this cord is pulled, it opens a small hole in the top of the balloon, and hot air escapes, which causes the balloon to slow down and/or descend. The balloon will float to earth if this valve is kept open long enough, and the air inside cools down to equal the temperature of the surrounding air. During descent, the balloon envelope acts rather like a parachute, allowing the basket to gently float to earth.
A hot air balloon pilot mostly has only vertical control, and even that is inexact, since there is a time delay between firing the burner and the balloon rising, or opening the parachute valve, allowing the balloon to descend. To move horizontally, pilots utilize altitude, air pressure, and wind direction to work in their favor.
The wind blows differently at various altitudes, and pilots understand this. Although it is possible to guide a hot air balloon horizontally to some extent, a pilot still doesn't have total control. For this reason, there is often a crew on the ground who follow the balloon in a "chase" vehicle and meet it when it lands, collecting both the equipment and the balloon passengers.
A smart hot air balloon pilot makes sure that the weather forecast is favorable before going up. Bad weather is the main enemy for a hot air balloon. Rain can damage the balloon, and lightning can destroy it. Therefore, hot air balloons can only be safely flown when the weather is ideal and wind conditions favorable.
If you're looking for a fun and exciting adventure, try taking a hot air balloon ride with an experienced and knowledgeable pilot. It's an experience you'll never forget! And now that you know how hot air balloons work, it will add even more to your enjoyment.
