July, the units had lost 16 Panthers due to mechanical breakdown, leaving only 184 available for the launching of the offensive. July and August 1943 saw the heaviest German ammunition expenditure on the Eastern Front up to that point, with 236,915 tons consumed in July and 254,648 in August. The previous peak had been 160,645 tons in September 1942. Red Army The Red Army used two Fronts for the defence of Kursk, and created a third front behind the battle area which was held as a reserve. The Central and Voronezh Fronts fielded 12 armies, with 711,575 men (510,983 combat soldiers) and 625,591 men (446,236 combat soldiers) respectively. In reserve, the Steppe Front had an additional 573,195 men (449,133). Thus the total size of the Soviet force was 1,910,361 men, with 1,426,352 actual combat soldiers. Soviet armour strength included 4,869 tanks (including 205 KV-1 heavy tanks) and 259 SPGs (including 25 SU-152s, 56 SU-122s and 67 SU-76s) Overall a third of the Soviet tanks at Kursk were light tanks, but in some units this proportion was considerably higher. Of the 3,600 tanks in the Central and Voronezh Fronts in July 1943, 1,061 were light as T-60 and T-70 tanks. With very thin armour and small guns, they were unable to effectively engage the frontal armour of German medium and heavy tanks or AFVs. The most capable Soviet tank at Kursk was the T-34. However, the original version was armed only with a 76.2mm gun, which struggled against unarmoured Panzer IVs, and the frontal armour of Tigers and Panthers was essentially impenetrable. Only the SU-122 and SU-152 self-propelled guns had the power to destroy the Tiger at short range, but they were not equal to the Tiger's 88mm gun at long range, and there were very few SU-122s and SU-152s at Kursk. Comparison of strength Operation Citadel Red Army offensive phase Preliminary actions Fighting started on the southern face of the salient on the evening of 4 July 1943, when German infantry launched attacks to seize high ground for artillery observation posts prior to the main assault. During these attacks, a number of Red Army command and observation posts along the first main belt of defence were captured. By 16:00, elements of the Panzergrenadier Division "Großdeutschland", 3rd and 11th Panzer Divisions had seized the village of Butovo and proceeded to capture Gertsovka before midnight. At around 22:30, Vatutin ordered 600 guns,