Hot air balloon are unaware that is possible to sail through the element air"). Persecuted by the Inquisition, he was prevented from continuing his research; however, he left designs for a manned air vessel. The French brothers Joseph-Michel and Jacques-Étienne Montgolfier developed a hot air balloon in Annonay, Ardeche, France and demonstrated it publicly on September 19, 1783, making an unmanned flight lasting 10 minutes. After experimenting with unmanned balloons and flights with animals, the first balloon flight with humans aboard, a tethered flight, performed on or around October 15, 1783, by Jean-Francois Pilatre de Rozier who made at least one tethered flight
Hot air ballooning forecasts. The pilot will also send up a helium pilot balloon, known as a "met-balloon" in the UK and "pibal" in the USA, prior to launch to get information about what the wind is actually doing. Another way to determine actual wind directions is to watch other hot air balloons, which are the equivalent of a large "met-balloon". The direction of flight depends on the wind, but the altitude of the balloon can be controlled by changing the temperature of the air inside the envelope. The pilot may open one or more burner blast valves to increase the temperature inside