Hot air balloon being inflated. Hot air balloons used for manned flight have a single layered fabric gas bag, referred to as the envelope, with an opening at the bottom called the mouth or throat (yellow coloured fabric). Attached to the envelope is a basket, or gondola, for carrying the passengers. Above the basket is the burner, which injects a flame into the envelope and produces the hot air needed to make to balloon rise.
Model release not available. Property release not required.