Althoug the front along the Soviet-Romanian border had remained relatively calm during the first days of the war, the German and Romanian armies awaiting the encirclement of the Soviet Southwestern Front.

As the Luftwaffe bombers attacked the movements of Soviet troops in the rear area of the Dnieper River. The main mission of the Bf 109 pilots was to seek out and destroy any enemy aircraft encountered in the air. The main tactic used was a series of constant Frie Jagd missions in small groups of Bf 109s over the vast battle area and the closest Soviet rear areas. A prolonged ridge of high pressure created clear skies, which provided the fighter pilots with the best possible conditions.

The first ten days of intense air activity had left no more than a few hundred VVS aircraft remaining in the entire southern combat zone. General-Leytenant Yevgeniy Ptukhin, a veteran of Spain who commanded VVS-Southwestern Front, was made scapegoat for the failure. On July 1 he was relieved from command and eventually executed by a firing squad.

Its interesting to note that the soviet pilots reported that the Romanian airmen lacked the experience of Luftwaffe and were an "easier' enemy. As a cosequence The Romanian Air Force suffered heavy losses, and most of its units were to be withdrawn from first-line.

On 2 July Oblt. Kurt Lasse, Obfw. Erwin Riehl and Fw. Wilhelm Baumgartner of 9./JG 77 had an encounter with seven MiG-3s led by the the ace Starshiy Leytenant Aleksandr Pokryshkin of 55 1AP, which were escorting nine SBs. During this encounter Baumgartner shot down his second enemy fighter, a Mig-3 flown another future ace, Mladshiy Leytenant Stepan Komlev. Komlev however was lucky and manage to leave his crippled machine by parachute. Lasse and Reihl manage to claimed three of the Soviet SB-2 bombers. Pokryshkin on the another hand filed an unsubstantiated claim of a Bf 109. Altogether on this day, the Jagdgruppen of Luftflotte 4 claimed fifty-six victories against three losses.

The next day, on 3 July Fw. Baumgartner belly land his "Gelb 2" after battle damage. However the machine was repaired and Baumgartner manage to add another five VVS fighter up to 15 October when he was forced down a second time due to technical problems. Landed behind enemy lines, 45 km South of Ischum he was promptly taken prisoner. However 14 days later Baumgartner manage to escape and was to return to his unit, his Bf 109 was also recovered.

On 11 April 1943, Obfw. Wilhelm Baumgartner would fly his last combat mission over Tunisia, while escorting Stukas he was downed by Spitfires from 232nd Sqn. 2 km south of Sedjoumi. His total is a bit unsertain and have been quoted from 34 to 40 abschüsse, including seven western flown fighters.