It was soon recognized by the Aviation Militaire that not only were the A.R. 1's and A.R. 2's underpowered, but also the Sopwith 1A2 Strutters were both too fragile and carried an inadequate payload. In 1916, therefore, the Aviation Militaire established a requirement for a 2-seat reconnaissance machine capable of carrying a crew of two, several machine guns, and a wireless set. The Société des moteurs Salmson designed a biplane based on their knowledge gained from the production of the Sopwith machines.

The Salmson 2 was powered by a 230 hp Salmson 9Za engine. The wings were of equal span with ailerons on both upper and lower wings. Armament consisted of a single fixed machine gun for the pilot and a twin machine gun configuration for the observer. The Salmson underwent STAé testing on 29 April 1917 and its performance was judged to be good. A production order was placed and eventually 3200 aircraft were manufactured. As the war progressed field modifications were carried out to allow the Salmson to carry 230 kg of bombs for ground attack duties.

The AEF air service purchased 705 Salmson 2's. The first 18 were delivered in April 1918 and were used to replace A.R. 1's and Sopwith 1 ½ Strutters. Salmson 2's saw duty in the following 1st Army with: 1st Corps Observation Group {1st and 12th Observation Squadrons}; 3rd Corps Observation Group {88th and 90th Corps Observation Squadrons}; 5th Corps Observation Group (99th and 104th Observation Squadrons}; 7th Corps Observation Group {258th Corps Observation Squadron}; and the 1st Army Observation Group {24th and 91st Army Observation Squadrons}. In addition, the 167th Corps Observation Squadron of the 2nd Army Observation Group used the Salmson.

The first Salmsons supplied to the 1st and 12th Aero Squadrons had a Lewis gun mounted on the upper wing. This position degraded performance so severely that they were removed. Some Salmsons were reequipped with a modified Lewis gun manufactured by the Savage Arms Co. Also, in some machines the pilot's Vickers gun was replaced by Marlin machine guns.