De Rozier's plan was an attempt to cross the English Channel from France to England. A Montgolfier balloon would not be up to the task, requiring large stocks of fuel for the hot air, so his balloon, the Rozière balloon, was a combination hydrogen and hot air balloon. It was prepared in 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 over land some 5 km from their starting point. According to contemporary accounts, the balloon caught fire in midair before suddenly deflating and crashing near Wimereux in the Pas-de-Calais, from an estimated height of 450 m (1,500 feet). Both occupants were killed.

 

Fatal accident at Wimereux, 15 June 1785.

 

Eight days later his former fiancée died, possibly having committed suicide. A commemorative obelisk was later erected at the site of the crash. The King had a medal struck, and gave his family a pension.

 

The modern hybrid gas and hot air balloon is named the Rozière balloon after his pioneering design.

 

Deaths of Rozier and Romain.