On 8 October, Hitler called for the air offensive to be carried out no later than 14 October, as he required air assets for a major effort at Stalingrad. As a result, on 10 October 1942, "Fliegerkorps" 4 of "Luftflotte" 4 (4th Air Corps of Fourth Air Fleet) was ordered to send every available bomber against the oilfields at Grozny. Fourth Air Fleet was in poor shape by this time – von Richthofen had begun Case Blue with 323 serviceable bombers out of a total of 480. He was now down to 232, of which only 129 were combat ready. Nevertheless, the force could still deliver damaging blows. Attacks on the refineries reminded von Richthofen of the attacks on Sevastopol several months earlier. Thick black smoke rose from the refineries to a height of . On 12 October, further raids caused even more destruction. It had been a strategic mistake not to have made greater efforts to hit the oil refineries at Grozny and Baku sooner, as their destruction would have been a greater blow to the Soviets than the loss of Stalingrad, where most of the air fleet was deployed. On 19 November, the Soviet counter-offensive at Stalingrad compelled von Richthofen to once more withdraw his units north to the Volga and bring an end to the aerial offensive.