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
2012 Ljubljana Marshes hot air balloon crash Civil Aviation Agency reported on 27 August 2012 that commercial hot air balloon flights were banned temporarily. The duration of the ban was not given, but the balloon crash was cited as the reason for the ban. Throughout the next year, all involved parties coordinated proposals for stricter rules, which were accepted, and new licenses were granted again starting in August 2013. In the meantime, several operators closed because they were prevented from selling flights, while the remaining ones faced severely reduced sales even after the ban was lifted. In their report, official accident investigators accused the pilot of using