On 18 January 1916, the decision was made to form a dedicated fighter squadron. On 22 February 1916, Escadrille I became the 1ère Escadrille de Chasse. It consisted of newly supplied Nieuport 10sand one obsolete Farman two-seater. In August, the new squadron would upgrade to Nieuport 11s, and Escadrille V was turned into the 5ème Escadrille de Chasse. The new unit was the first to mount an offensive formation for the new air force; on 15 February 1917, they flew an offensive patrol of seven. By this time, the AMB had grown to 44 aircraft, including 21 fighters. At this point, individual aircraft bore personal markings affixed by their pilots, but no unit designations.