AY Honors/Hot Air Balloons/Answer Key

The Montgolfier brothers, Joseph Michel Montgolfier (August 26, 1740 – June 26, 1810) and Jacques Étienne Montgolfier (January 6, 1745 – August 2, 1799), inventors of the montgolfière hot air balloon.

The brothers were the sons of a paper manufacturer at Annonay, south of Lyon, France. When playing with inverted paper bags over open fire they found that the bags rose to the ceiling. This led them to experiment further with larger bags made of other materials. During 1782 they tested indoors with silk and linen.

On December 14, 1782 they succeeded in an outdoor launch of an 18 m³ silk bag, which reached an altitude of 250 m.

On June 5, 1783, as a first public demonstration, they sent up at Annonay a 900 m linen bag inflated with hot air. Its flight covered 2 km, lasted 10 minutes, and had an estimated altitude of 1600 - 2000 m.

The subsequent test sent up the first living beings in a basket attached to the balloon: a sheep, a duck and a cockerel, to ascertain the effects of the air at higher altitude. This was performed at Versailles, before Louis XVI of France, to gain his permission for a trial human flight.

An ascent in a fixed balloon took place around October 15 (12 or 14 according to Montgolfier), to an altitude of 26 m.

On November 21, 1783, the first free flight by humans was made by Pilâtre de Rozier and Marquis d'Arlandes who flew aloft for 25 minutes about 100 metres above Paris for a distance of nine kilometres.

This was followed by further flights, including a crossing of the English Channel on January 7, 1785, by Jean-Pierre Blanchard and John Jeffries.

Only one of the brothers (the exact one is unkown) ever flew himself in a balloon, and then only once.

Hot air balloons soon were superseded by hydrogen gas balloons and did not return until the 1960s when propane gas became available as a practical fuel.