On July 29, 1943, I./JG 27, coming from southern France, the pilots flew in and landed at Munster Handorf, where at the same time the ground personal was also transported by rail from France.

From here the Gruppe continued to fly combat missions as part of Reichsverteidigung, the defense of the Reich where it should be used intercepting the increasingly frequent and heavy daytime attacks from the 8th USAAF and their four-engine bomber formations.

When they arrived in Münster-Handorf, I./JG 27 had a total of 40 aircraft, half of which were Bf 109 G-4s and half G-6s, the former were all supposed to be replaced by Bf 109 G-6s. However this was not possible because the deployment of new aircraft at that time was not sufficient to be able to provide the required number of new machines of the G-6 series for all fronts in the East, south and over the Reich.

Instead, all machines of I./JG 27 were equipped with two additional 2 cm MG 151/20 cannons under the wings, the so-called "Gondolbewaffing", to better deal with the 4-engine bombers.

On 12 August the Gruppe would fly their first mission against the 8th USAAF as their 4-engine bomber where out searching for "targets of opportunity". The I./JG 27 made contact with the enemy over Remscheid where they attacked the enemy formations. After returning to base, the pilots filed claims for a total of nine B-17, although five was later confirmed with another HSS (outshooting) was accepted, all for the loss of two Bf 109 G-4s.

The next mission against the USAAF would be their most successful during 1943. On this day, on 1 October when 12th USAAF attacked the Wiener neustädter Flugzeugwerke WNF aircraft plants with 50 to 60 B-24, 4-engine bombers.

Five minutes after the bombers had released their bombs, at 12.50 the I./JG 27 attacked the boxes of bombers hacking them to pieces. In all the Gruppe filed claims or 20 bombes including HSS. This was rather inflated numbers and finally the RLM accepted six of the eleven abschüsse and accepted another nine HSS. All for an own loss of one G-4 and it´s pilot Uffz. Hermann Sewrin.

One of the pilots that claimed a B-24 over Wiener Neustadt this day was Obfw. Rainer Pöttgen, also a claim that was later refuted by the RLM.

Pöttgen that was not know for his number of downings, earned his name as an excellent wing-man for Hans-Joachim Marseille, protecting his leaders back during 100 combat missions.

When the year ended I./JG 27 had been accredited with another 12 4-engine bombers and two HSS losing five Bf 109s and with them three wounded. Ofw. Rainer Pöttgen, would survive the war with a total of seven confirmed victories.