Jean-François Pilâtre de Rozier the autumn of 1784, but the attempt was not launched until after another Frenchman, Jean-Pierre Blanchard, and American companion, Dr John Jeffries, flew across the English Channel in a hydrogen gas balloon on 7 January 1785, from England to France. Despite several attempts, De Rozier and his companion, Pierre Romain, were not able to set off from Boulogne-sur-Mer until 15 June 1785. After making some progress, a change of wind direction pushed them back to land some 5 km from their starting point. The balloon suddenly deflated (without the envelope catching fire) and crashed near Wimereux in the Pas-de-Calais, from
Hot air balloon Montgolfier brothers, and had its first public demonstration on 4 June 1783 with an unmanned flight lasting 10 minutes, followed later that year with manned flights. The 1785 Rozière balloon, a type of hybrid balloon, named after its creator, Jean-François Pilâtre de Rozier, has a separate cell for a lighter than air gas (typically helium,) as well as a cone below for hot air (as is used in a hot air balloon) to heat the helium at night. Hydrogen gas was used in the very early stages of development but was quickly abandoned due to the obvious danger of introducing