Not long after the first manned flight in a hot air balloon in 1783 were the possibilities of its military benefits realized. The 1794 Battle of Fleurus, south of Brussels, took place during the French Revolutionary Wars between the army of the First French Republic and the Coalition Army. The French side possessed a reconnaissance balloon, l’Entreprenant, which was operated by the Aerostatic Corps. The French Aerostatic Corps was founded in 1794 operate and maintain these hydrogen-filled balloons for the French army.
During prelude to the battle, the corps received orders to move their already inflated balloon in front of the Austrian troops, and need 20 soldiers to hold on to and move it the 30 miles into place. For three days an officer would ascend and make observations. On the the fourth day, the start of the battle, the balloon remained afloat for nine hours with observations of troop movements provided by notes dropped to the ground and via flag semaphore.
The French won the battle decisively, but with uncertain benefits. The Aerostatic Corps were deployed for three more major battles. One balloon company was captured by the Austrians in 1796 after a French defeat, with L’Intrépide still on display in Vienna’s Military History Museum today. Under a new General, the Corps was largely prevented from operating, and during the Napoleonic Campaign in Egypt the ballooning equipment was destroyed in the Battle of the Nile. After this point the Aerostatic Corps only conducted a few demonstrations, mainly for entertainment purposes, before being completely disbanded in 1802.
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