time they could stay in the air and choose when and how to engage in combat. Battle The Battle of Arras began on 9 April 1917. The Allies launched a joint ground offensive, with the British attacking near Arras in Artois, northern France, while the French offensive was launched on the Aisne. In support of the British army, the RFC deployed 25 squadrons, totalling 365 aircraft, about one-third of which were fighters (or "scouts" as they were called at the time). There were initially only five German Jastas (fighter squadrons) in the region, but this rose to eight as the battle progressed (some 80 or so operational fighter aircraft in total). Since late 1916, the Germans had held the upper hand in the contest for air supremacy on the Western Front, with the twin-lMG 08 machine gun-armed Albatros D.II and D.III outclassing the fighters charged with protecting the vulnerable B.E.2c, F.E.2b and Sopwith 1½ Strutter two-seater reconnaissance and bomber machines. The Allies' fighter squadrons were equipped with obsolete "pushers" such as the Airco DH.2 and F.E.8 – and other outclassed types such as the Nieuport 17 and Sopwith Pup. Only the SPAD S.VII and Sopwith Triplane could compete on more or less equal terms with the Albatros; but these were few in number and spread along the front. All four of the aforementioned Allied designs depended on just one synchronized Vickers machine gun apiece, given cooling louvers on the cooling jackets for aviation use, for their armament on their airframe. The new generation of Allied fighters were not yet ready for service, although No. 56 Squadron RFC with the S.E.5 was working up to operational status in France, intended to use both the synchronized Vickers gun, and an overwing-mount Lewis machine gun firing above the propeller arc for a twin-gun offensive punch. The Bristol F2A also made its debut with No. 48 Squadron during April, but lost heavily on its first patrol, with four out of six shot down in an encounter with five Albatros D.IIIs of Jasta 11, led by Manfred von Richthofen (popularly known as the Red Baron). The new R.E.8 two-seaters, which were eventually to prove less vulnerable than the B.E.2e, also suffered heavy casualties in their early sorties. During April 1917, the British lost 245 aircraft, 211 aircrew killed or missing and 108 as prisoners of war. The German Air Services recorded the loss of 66