Hot air balloon sea level, and humidity of the air surrounding. On a warm day, a balloon cannot lift as much as on a cool day, because the temperature required for launch will exceed the maximum sustainable for nylon envelope fabric. Also, in the lower atmosphere, the lift provided by a hot air balloon decreases about 3% for each 1,000 meters (1% per 1,000 ft) of altitude gained. Standard hot air balloons are known as Montgolfier balloons and rely solely on the buoyancy of hot air provided by the burner and contained by the envelope. This style of balloon was developed by the
London International Hot Air Balloon Festival London International Hot Air Balloon Festival The London Hot-Air Balloon Festival (London Balloon Festival) was an annual hot-air balloon festival held in London, Ontario, Canada. The festival, which was held for the first time in 1984 and originally called the London Balloon "Fiesta", used to take place in Harris Park at the forks of the Thames River during Simcoe Day (first Monday in August) weekend. The sponsor of the festival was Sundance Balloons. Spectators could get very close to the balloons, as there was no fixed barricades separating the launch area. Several special-shaped balloons regularly attended, including the Canadian Flag,