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 Carterton hot air balloon crash in Carterton, a town of 4100 people in north-eastern Wellington Region, on a 45-minute scenic flight over the Carterton area, carrying ten passengers. The Masterton-based pilot was one of New Zealand's most experienced balloon pilots, with more than 10,000 hours flying time, and was the safety officer for the "Balloons over Wairarapa" hot air balloon festival, held annually in March around the Carterton and Masterton area. The ten passengers were all from the greater Wellington Region: two husband-and-wife couples from Masterton and Wellington, a couple from Lower Hutt, a boyfriend and girlfriend from Wellington, and two cousins from Masterton and