A French military balloon or aerostat in August 1796 during the siege of Mantua. In the campaign in Italy, part of the French Revolutionary Wars, the French forces under the command of Napoleon Bonaparte besieged and blockaded the large Austrian garrison at the Italian city of Mantua (Mantova) from July 1796 until February 1797, when it surrendered. In 1794, the world's first air force, the French Aerostatic Corps (Compagnie d'A廨ostiers, Commandant Coutelle), was founded for military operations. Its functions included reconnaissance, signalling and the distribution of propaganda. Balloons were an early instrument in accurate intelligence collection and their observations were particularly useful in the preparation of battlefield maps.Their presence often had a demoralising affect on the enemy but the aeronauts were vulnerable to enemy gunfires when the wind took the wrong direction.