A typical balloon is about 55 feet across and 60 to 80 feet tall. They are categorized by
how much air the envelope can contain. a common sizes is the AX-7, with an envelope volume
of 77,000 cubic feet. This is the most widely flown model because it can be easily handled
by a crew of three to four people. A typical envelope has aboiut 1,200 yards of material
and about 3 miles of thread.
How Many People?
The size and capacity of the envelope determines the lift of the balloon, and hence how
many people can be flown safely in the balloon. Less obvious, other factors are equally
important: ambient temperatures, altitude above sea level, and passenger weight. These
factors combined determine how many people can fly safely on a given day.
A typical AX-7 system weighs about 550 pounds: the envelope weighs about 200 pounds, and
the basket, fuel, and on-board equipment add another 350 pounds.
A balloon can fly, with proper weather conditions, up to 12,500 feet above sea level
before oxygen is required. However, most passengers enjoy lower altitude flights, where
they can talk to people on the ground, do touch-and-go (or, for the adventurous,
splash-and-dash) landings, and experience the terrain below from a distance where details
can be observed.
Balloons are flown in early morning or late afternoon because winds are usually calmest
for 2 to 3 hours after sunrise, and 2 to 4 hours before sunset. Mid-day flights are rare
due to wind and thermal activity. Flights usually last from 45 minutes to one hour, due to
safety, weather and fuel capacity.
Balloons drift with the wind and at the same speed as the wind. Since winds blow in
different directions at different altitudes, the pilot can change direction by changing
altitude. The pilot ascends or descends by heating the air inside the balloon with the
burner, or descend by letting the air in the balloon cool.
The fuel is liquid propane gas, the same gas used in an outdoor barbecue grill. Propane is
environmentally-friendly, as it is clean burning, producing only water vapor and carbon
For safety, balloons have 2 completely independant burner systems. Even if both of the
burners were to fail, the balloon itself acts as a giant parachute. In such a rare event,
the balloon descends to earth at about the same rate as a parachute, approximately 9 to 10
miles per hour.
Pilots are certified by the FAA as either a student, private, or commercial pilots.
Students receive training from certified commercial hot-air balloon flight instructors.
Students must complete extensive classroom and practical training. Studenst take written
exams as well as flight and oral exams for both private and commercial certificates. Our
pilots make sure they are always well-rested before a flight.
Aside from the basket, burner and envelope, certain equipment is required in all balloons,
including: a compass, an altimeter (altitude above sea level), a variometer (rate of
ascent or descent), an envelope temperature indicator, and fuel quantity guages for all
How Does All That Air Get In There?
For inflation, the balloon is spread out on the ground with the basket on its side, and
while the mouth of the balloonis held open by crew members, a large fan is used to blow
air into the envelope. Since the envelope is so light, the balloon can be almost entirely
filled with air by the fan. Once the balloon is almost full of air, the pilot will ignite
the burner and heat the air. Both basket and envelope rise into an upright position as the
air is heated.
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