Hot Air Balloon flights in Australia are at dawn because this is the time of day that provides the optimum weather conditions for launching balloons. Depending on many operational factors, which vary each day, passengers may be on the ground during inflation or in the balloon when the sun is rising. Either way, the Australian sky during the first hour of light is always amazing. We hope this ballooning resource will help answer your questions that you might have about what its like to fly in a hot air balloon, some of the regulation and rules that CASA puts in place for hot air ballooning in Australia and about booking your trip with Hot Air Why does hot air ballooning take place so early in the morning?
How many people will be in the balloon basket? What do I bring on a morning balloon ride? Where do the Hot Air balloons fly over? Why should I choose to balloon in Queensland, Australia? What are hot air balloons made of? How is a hot air balloon inflated? How tall is a hot air balloon? How is a hot air balloon steered? Can anyone do it? What about Vertigo - I hate heights?
How high do hot air balloons fly? How far do hot air balloons fly? Is wind required to fly? What regulations are in Place? What is the minimum age a child can fly in a hot air balloon?
Are the prices for each tour per adult? Which hotel and places do we pick up from? What time does ballooning get back? How long before I want to fly should I book?
Are the balloon flights at sunrise? Why do Hot Air Balloon flights take place so early in the morning? What do I bring on a morning, hot air ballooning? Where do Hot Air fly? Many of our Virgin balloon baskets have bench seats which can be used for landing. It is fixed to a metal frame attached above the basket under the mouth of the envelope.
The burner mixes liquid propane from pressurised gas tanks with oxygen and ignites it. The pilot pulls a small valve which fires the burner and aims the flame into the mouth of the balloon to heat the air inside. Our balloons have two burners including one which lets propane out more slowly making it quieter. Our balloons generally also have specially-fitted heat shields below the burners which stop it getting too toasty for you but we still recommend a hat.
Hot air balloons work because hot air rises. By heating the air inside the balloon with the burner, it becomes lighter than the cooler air on the outside. This causes the balloon to float upwards, as if it were in water. Obviously, if the air is allowed to cools, the balloon begins to slowly come down. Pilots have a great deal of control over the altitude of the balloon which they monitor with various instruments.
Balloons cannot be steered in the normal sense of the word so they travel in the direction of the wind, which varies at different altitudes. Pilots skillfully use this as a way of changing direction by burning to go up, or allowing the air to cool to go down, and catch different air streams at different heights. Pilots can use turning vents in the side of the balloon to rotate it degrees so you have a full panoramic view and to make the broad side of the basket lead for landing.
Pilots bring the balloon into land, usually after around an hour in the air on a passenger flight, when they see a safe open space often out in the countryside. If it looks like the wind would take the balloon into prohibited air space, the crew needs to find a new launch spot.
In the air, the pilot will use an onboard altimeter , variometer and their own observations to find the right altitude.
Reaching the right altitude is pretty tricky because there is at least a second delay between blasting the burners and the balloon actually lifting.
Balloon pilots have to operate the appropriate controls just a little bit before they want to rise, and shut them off a little bit before they want to stop rising. Inexperienced pilots often overshoot, rising too high before leveling off.
Controlled operation comes only with many hours of ballooning experience. Now that we've seen how a hot air balloon flies through the air, let's look at the forces that make this possible. As it turns out, hot air balloons are a remarkable demonstration of some of the most fundamental forces on earth. One amazing thing about living on earth is that we are constantly walking around in a high-pressure fluid -- a substance with mass and no shape.
The air around us is composed of several different elements in a gaseous state. In this gas, the atoms and molecules of the elements fly around freely, bumping into each other and everything else. As these particles collide against an object, each of them pushes with a tiny amount of energy. Because there are so many particles in the air, this energy adds up to a considerable pressure level at sea level, about The force of air pressure depends on two things:.
These factors are determined by how many air particles there are in an area and how fast they are moving.
If there are more particles, or if they are travelling more quickly, there will be more collisions, and so greater pressure.
Increasing particle speed also increases the force of the particle's impact. Most of the time we don't notice air pressure because there is air all around us. All things being equal, air particles will disperse evenly in an area so that there is equal air density at every point.
Without any other forces at work, this translates to the same air pressure at all points. We aren't pushed around by this pressure because the forces on all sides of us balance one another out.
For example, The chair doesn't feel substantially greater pressure from any particular angle. So, with no other forces at work, everything would be completely balanced in a mass of air, with equal pressure from all sides.
But on Earth, there are other forces to consider, chiefly gravity. While air particles are extremely small, they do have mass, and so they are pulled toward the Earth. At any particular level of the Earth's atmosphere, this pull is very slight -- the air particles seem to move in straight lines, without noticeably falling toward the ground.
So, pressure is fairly balanced on the small scale. Overall, however, gravity pulls particles down, which causes a gradual increase in pressure as you move toward the earth's surface.
All air particles in the atmosphere are drawn by the downward force of gravity. But the pressure in the air creates an upward force working opposite gravity's pull. Air density builds to whatever level balances the force of gravity, because at this point gravity isn't strong enough to pull down a greater number of particles.
This pressure level is highest right at the surface of the Earth because the air at this level is supporting the weight of all the air above it -- more weight above means a greater downward gravitational force. As you move up through levels of the atmosphere, the air has less air mass above it, and so the balancing pressure decreases.
This is why pressure drops as you rise in altitude. This difference in air pressure causes an upward buoyant force in the air all around us. Essentially, the air pressure is greater below things than it is above things, so air pushes up more than it pushes down.
But this buoyant force is weak compared to the force of gravity -- it is only as strong as the weight of the air displaced by an object. Obviously, most any solid object is going to be heavier than the air it displaces, so buoyant force doesn't move it at all.
The buoyant force can only move things that are lighter than the air around them. For buoyancy to push something up in the air, the thing has to be lighter than an equal volume of the air around it. The most obvious thing that is lighter than air is nothing at all. A vacuum can have volume but does not have mass, and so, it would seem, a balloon with a vacuum inside should be lifted by the buoyancy of the air around it.
This doesn't work, however, because of the force of surrounding air pressure. Air pressure doesn't crush an inflated balloon, because the air inside the balloon pushes out with the same force as the outside air pushing in.
A vacuum, on the other hand, doesn't have any outward pressure, since it has no particles bouncing against anything. Without equal pressure balancing it out, the outside air pressure will easily crush the balloon. And any container strong enough to hold up to the air pressure at the earth's surface will be much too heavy to be lifted by the buoyant force.
Another option would be to fill the balloon with air that is less dense than the surrounding air. Because the air in the balloon has less mass per unit of volume than the air in the atmosphere, it would be lighter than the air it was displacing, so the buoyant force would lift the balloon up. But again, fewer air particles per volume means lower air pressure, so the surrounding air pressure would squeeze the balloon until the air density inside was equal to the air density outside.
All of this is assuming that the air in the balloon and the air outside the balloon exist under exactly the same conditions. If we change the conditions of the air inside the balloon, we can decrease density, while keeping air pressure the same. As we saw in the last section, the force of air pressure on an object depends on how often air particles collide with that object, as well as the force of each collision. We saw that we can increase overall pressure in two ways:.
So, to lower air density in a balloon without losing air pressure, you simply need to increase the speed of the air particles. You can do this very easily by heating the air. The air particles absorb the heat energy and become more excited. This makes them move faster, which means they collide with a surface more often, and with greater force. For this reason, hot air exerts greater air pressure per particle than cold air, so you don't need as many air particles to build to the same pressure level.
So a hot air balloon rises because it is filled with hot, less dense air and is surrounded by colder, more dense air. The basic idea behind hot air balloons has been around for a long time. Archemedes, one of the greatest mathematicians in Ancient Greece, figured out the principle of buoyancy more than 2, years ago, and may have conceived of flying machines lifted by the force.
In the 13th century, the English scientist Roger Bacon and the German philosopher Albertus Magnus both proposed hypothetical flying machines based on the principle. But nothing really got off the ground until the summer of , when the Montgolfier brothers sent a sheep, a duck and a chicken on an eight-minute flight over France.
The two brothers, Joseph and Etienne, worked for their family's prestigious paper company. As a side project, they began experimenting with paper vessels elevated by heated air.
Over the course of a couple years, they developed a hot air balloon very similar in design to the ones used today. But instead of using propane, they powered their model by burning straw, manure and other material in an attached fire pit. The sheep, duck and chicken became the first balloon passengers on Sept. They all survived the trip, giving the King some assurance that human beings could breath the atmosphere at the higher elevation. Two months later, the Marquis Francois d'Arlandes, a major in the infantry, and Pilatre de Rozier, a physics professor, became the first human beings to fly.
Other hot air balloon designs and ambitious flights followed, but by , the hot air balloon had been largely overshadowed by gas balloons. One factor in this popularity decline was the death of Pilatre de Rozier in an attempted flight over the English Channel.
The new balloon he built for the flight included a smaller hydrogen balloon in addition to the hot air balloon envelope. The fire ignited the hydrogen early in the flight, and the entire balloon burst into flames.
But the main reason hot air balloons fell out of fashion was that new gas balloon dirigible designs were superior in a number of ways -- chiefly, they had longer flight times and could be steered. Another popular balloon type was the smoke balloon. These balloons were lifted by a fire on the ground, and did not have any attached heat source. They simply shot up in the air, and then sank back to the ground.
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