Montgolfier unmanned hot air balloon flight of 1783, illustration. Following their earlier launch of a hydrogen balloon, this hot air balloon was launched by the Montgolfier brothers. It ascended over the Palace of Versailles, France, on 19 September 1783. The royal family and a large crowd were watching. A sheep, duck and rooster were in the basket below the balloon, but no humans. The animals were later safely recovered, demonstrating that it was possible to survive an aerial flight.