Montgolfier brothers Montgolfier brothers Joseph-Michel Montgolfier (26 August 1740 – 26 June 1810) and Jacques-Étienne Montgolfier (6 January 1745 – 2 August 1799) were paper manufacturers from Annonay, in Ardèche, France best known as inventors of the Montgolfière-style hot air balloon, globe aérostatique. They launched the first piloted ascent, carrying Étienne. Joseph Michel also invented the self-acting hydraulic ram (1796), Jacques Étienne founded the first paper-making vocational school and the brothers invented a process to manufacture transparent paper. The Montgolfier brothers Joseph-Michel and Jacques-Étienne were born into a family of paper manufacturers founded in 1534 in Annonay, in Ardèche, France. Their parents
Hot air balloon course) stated in the previous section. Liftoff would require a slightly greater temperature, depending on the desired rate of climb. In reality, the air contained in the envelope is not all the same temperature, as the accompanying thermal image shows, and so these calculations are based on averages. For typical atmospheric conditions (20 °C, 68 °F), a hot air balloon heated to (99 °C, 210 °F) requires about 3.91 m³ of envelope volume to lift 1 kilogram (62.5 ft³/lb). The precise amount of lift provided depends not only upon the internal temperature mentioned above, but the external temperature, altitude above