The balloon bag or "envelope" is made of reinforced nylon fabric. It is very light (1.3 ounces per square yard) but very strong (125 pounds per square inch). The envelope is treated with a polyurethane coating to make it more airtight and to help the fabric withstand the ultraviolet rays of the sun. The pilot and passengers ride in a gondola (or basket) that is made of woven wicker, which is both strong and flexible. The gondola is connected to the envelope by stainless steel suspension cables.
HOW DO BALLOONS WORK?
Hot air rises. The envelope traps a large bubble of hot air. If the air in the envelope is heated by a burner, the balloon will rise. If the air in the envelope is allowed to cool or if the hot air is "vented" (allowed to escape) from the top or the side of the envelope, the balloon will descend. An altimeter (to measure altitude), a rate-of-climb meter, and an envelope temperature gauge are the only instruments used in the balloon. Amazingly, the pilot can control the altitude of the balloon within a matter of inches!
HOW BIG ARE BALLOONS?
The most popular sport balloon is approximately 55 feet wide (diameter) and 70 feet high, which is about the same as a 7-story building. It has 1,075 square yards of nylon fabric in its envelope (or one-fifth of an acre in surface area), more than 3 miles of thread, and almost one-half mile of nylon webbing (used for reinforcing). Its 77,550 cubic foot air capacity displaces almost 3 tons of air and could hold 62,279 bushels of apples or 579,340 gallons of water. These sport balloons can carry 3 to 4 people.
HOW ARE BALLOONS INFLATED?
The balloon envelope is spread on the ground and the gondola laid on its side and attached to the envelope cables. A portable (gasoline powered) fan pushes cold air into the envelope. When the envelope is about half inflated with outside (ambient) air, a propane burner is ignited until the air inside is heated enough for the balloon to rise to an upright position. With a small amount of additional heat, the balloon becomes buoyant. Typically, the inflation takes about 20 minutes.
HOW MANY PEOPLE DOES IT TAKE TO FLY A BALLOON?
The sport of ballooning is a wonderful group or family activity. To safely launch and fly a balloon requires a minimum crew of
four people. Duties of the crew typically include launch preparation, following the balloon flight in the chase vehicle, obtaining permission of the landowner for the balloon landing and retrieval, keeping spectators out of the landing area, and insuring that gates are left as they are found and that property is not
HOW MUCH DO BALLOON SYSTEMS WEIGH?
A typical balloon system - envelope, gondola, fuel tanks, and
40 gallons of fuel - will weigh about 600 pounds, deflated on the ground. In the air, the complete system, including the weight of the air inside the envelope, will weigh about 2 ½ tons.
WHAT KIND OF FUEL DO BALLOONS USE?
Common Liquid propane gas (LPG) is used to heat hot air balloons. Some balloons carry 40 gallons of propane in two 20-gallon stainless steel tanks; others carry three 10-gallon tanks. Propane is a stable and predictable fuel, but highly volatile (burns easily). It is carried in liquid form, under pressure in the tanks, and supplied to the burners through flexible hoses. The burner flame may shoot out 6 to 8 feet in the blast that the pilot controls. A typical flight lasting 1 hour, with
5 people aloft, will consume about 20 gallons of propane. Some balloons have two independent burner and fuel systems for added safety.
WHERE DO BALLOONS LAND?
Since a balloon travels with the wind, it is not possible to determine an exact landing site prior to launch. However, a pilot is able, through the study of wind currents, to determine the general direction of the flight.
CAN ANYONE PILOT A BALLOON?
Balloon pilots must have an FAA issued aircraft pilot's
certificate especially for balloons. This certificate is issued by the Federal Aviation Administration (FAA) and is earned after taking hours of instruction with a balloon pilot instructor, passing an FAA written test, making a solo flight, and passing a flight test with an FAA examiner. Currently there are more than 3,200 balloons in the United States.
HOW DO PILOTS STEER BALLOONS?
Generally speaking, they don't. A balloon drifts in the same direction and at the same speed as the wind. The skill is for the pilot to pick the altitude that has the most desired wind direction. Surface winds sometimes blow in a very different direction from the winds aloft. Altitude control is achieved with the on-board burner. Longer "burns" will achieve lift. Shorter "burns", or none at all will allow the air to cool, and the balloon to descend.
HOW FAST DO BALLOONS GO?
As fast as the wind blows. But if the wind is over 8 miles per hour at ground level, balloons are not normally going to be inflated because of the increased possibility of burning the fabric and because landing would likely be rough and require a large field.
HOW HIGH DO BALLOONS GO?
Flights in hot air balloons have been recorded at over 50,000 feet. However, the sport of ballooning is most enjoyable when flying 200 to 500 feet - just above the treetops. When balloons fly over populated areas, they maintain an altitude of at least 1,000 feet.
HOW LONG CAN BALLOONS STAY UP?
Most balloons can fly for about 1 hour depending on the outside temperature and the weight carried. On a cold day with only the pilot flying, a 2-3 hour flight would be possible.
WHEN IS THE BEST TIME TO FLY?
Hot air ballooning is a year-round sport. Weather conditions for ballooning are best just after sunrise and 2-3 hours before sunset. Light, ideal winds (0-8 mph) often occur during these times. During the day, when the sun is high, thermals (large bubbles of hot air that rise from the sun-heated earth) make ballooning hazardous.
HOW MUCH DOES A BALLOON COST?
The average new balloon costs from $30,000 to over $80,000. This price includes the envelope, gondola, fuel tanks, and instruments, but does not include any ground support equipment.
Add to that the truck & trailer, radios, continuing education and feeding the
ravenous crew the investment is well over $100,000.
HOW DO YOU GET HOME AGAIN?
After the balloon is launched, the "chase crew" follows in a chase vehicle. Using maps of the area,
GPS, and radios, as well as visual contact, they try to be close-by when the balloon lands. The crew helps the pilot deflate and disassemble the balloon and return passengers and equipment back
to the starting point.