It was on this day in aviation history at bout 14.00h that a hot air balloon with Jean-François Pilâtre de Rozier and François Laurent le Vieux d’Arlandes as occupants lifts of from the gardens of Château de la Muette near bosi de Boulogne. (The home off King Louis XVI and Marie-Antoinette) It is the first untethered flight with humans onboard. All previous hot air balloon flights were either tethered or unmanned.
1786 drawing of the balloon flown by de Rozier and M. le Marquis d’Arlandes
The balloon had been designed and built by the inventors of the hot air balloon Joseph-Michel Montgolfier and Jacques-Étienne Montgolfier.
The fact that de Rozier and M. le Marquis d’Arlandes
Becoming the first to fly in an untethered balloon was a feat in itself. King Louis XVI had decreed that the first untethered flight should be made with condemned criminals as passengers. This was to avoid killing honourable men. De Rozier successfully petitioned that he and d'Arlandes should be allowed to make the flight.
Etches by André Pujos, (ca. 1784) of the first two men to fly untethered Public Domain)
De Rozier had some experience in balloon flights as he had made several tethered flights, learning how to control the balloon. On this flight, the balloon rose to an altitude (estimated) of approximately 3000 feet (910 meters).
After approximately 25 minutes of flight, they landed at Butte-aux-Cailles, outside Paris. Distance covered, five miles ( 8kilomters) The decision to land was made, earlier than planned, because the envelope of the balloon was being scorched by embers from the fire heating up the balloon. Some specifications of the balloon;
Height 75 feet (22.8 meters)
Diameter 50 feet (15.24 meters)
Volume 60.000 cubic feet (~1700 cubic meters)
Envelope Taffeta (woven silk coated with a mixture of alum and varnish)
Heating source Burning cole