2 Ju 87s, 1 Do 17 and 10 transport and reconnaissance aircraft). Also lost were 12 aircraft from the Romanian Air Force. In a desperate bid to stop the rapid German advance the Soviets sent huge waves of unescorted bombers to blunt the German Panzer divisions thrusts into Soviet territory. The result was appalling Soviet losses. Jagdgeschwader 77 shot down 47 VVS bombers on the 25 June. A particularly disastrous day for the Russians came on 29 June when Jagdgeschwader 51 shot down 65 bombers during the day. By the 18 July it had shot down 500 Soviet aircraft in combat. The Germans were assured of air-superiority throughout the year. The VVS, although continually resisting, was powerless to prevent the Luftwaffe inflicting heavy losses to Soviet ground forces, and for the rest of 1941 the Luftwaffe could devote much of its energy to these ground support missions. In the following two days the Soviets reported the loss of another 1,922 aircraft. Three weeks into the campaign German pilot Werner Mölders scored his 100th aerial victory, the first pilot to do so. The Luftwaffe was particularly effective in breaking up and destroying Soviet armored divisions. The Soviet tank force had an estimated strength of 15,000 tanks at the beginning of the invasion. By October that force had, in the central sector, been reduced to 150. Despite the clear victories being won and the rapid advances deep into Soviet territory, the Luftwaffe had lost nearly 1,000 aircraft destroyed within the first two months. It became apparent that the Luftwaffe could not sustain these losses for long. The increasing distances meant delivery of replacement manpower and machinery took much longer and spare parts to replace battle damaged aircraft became a problem. Despite this the Luftwaffe had reduced the Soviets to a mere 389 aircraft in the central sector of the front. The Luftwaffe supported all three army groups in their push eastward and it helped the ground forces achieve a spectacular victory at Kiev in which an estimated 600,000 Red Army soldiers were killed or captured. The impact of the Luftwaffe during these months was critical to the pace of the advance. During the Battle of Kiev the Luftwaffe accounted for 2,171 Soviet vehicles and 23 Soviet tanks, and 107 Soviet aircraft destroyed between 12 and 21 September 1941, and inflicted heavy casualties to the Soviet ground troops. Soviet prisoners revealed that the