The first dive bombers unit, Stukagruppe 162, was created in Germany in 1934. It was better known under its unofficial name “Stukkagruppe Schwerin”. The wing was equipped with the Heinkel He 50 A aircraft. On April 3, 1935, the dive bomber wing was named after Max Immelmann. In March 1936, the unit stationed at Schwerin was renamed to I./Stukagruppe 162 “Immelmann”.
In the second half of 1936, the outdated Heinkel 50 A was replaced by two-seater Henschel Hs 123 A-0 and A-1 biplanes. In February 1937, I./Stukagruppe 162 received the first Junkers Ju 87 A-0 dive bombers.
In spring of 1937, III./Stukagruppe 162 “Immelmann” was formed at the Insterburg base, under command of Maj. Holle. The unit was initially equipped with the A-1 variant of the Junkers Ju 87 and later was rearmed with the A-2 type. In autumn of 1937, III./Stukagruppe 162 “Immelmann” was relocated to Breslau and its designation was changed to I./Stukageschwader 163 “Immelmann”.
In June 1938, Fliegergruppe 50 was formed at the Lager Lechfeld airfield under command of Hptm. Ott. The wing consisted of three squadrons commanded by Oblt. Steen (7. Staffel), Oblt. Merz (8. Staffel) and Lt. Brücker (9. Staffel). The unit was initially equipped with the Henschel Hs 123 biplanes which were later replaced by the Junkers Ju 87 A. In early autumn of 1938, the unit was transferred to Algrottkau in Silesia and later, in October of the same year, relocated to the Paulsgrund airfield in Ratibor. Soon, according to the Munich Agreement legitimizing the Nazi Germany occupation of the Sudetenland, the unit participated in annexation of the western borderland of Czechoslovakia. After the operation, the unit was relocated to the Breslau-Schöngarten airfield and renamed to II./St.G 163. On May 1, 1939, a new Luftwaffe wing was created. Its official name was Sturzkampfgeschwader “Immelmann” 2 (St.G 2 “Immelmann”). The unit comprised three dive bomber squadrons. I./St.G 2 “Immelmann” (formerly I./St.G 163) that included Stab, 1./St.G 2, 2./St.G 2 and 3./St.G 2 was stationed at Cottbus. II./St.G 2 “Immelmann” (formerly I./St.G 162) composed of Stab, 4./St.G 2, 5./St.G 2 and 6./St.G 2 stationed at Stolp-Reiz. III./St.G 2 “Immelmann” (formerly II./St.G 163) with its home base at Langensalza included Stab, 7./St.G 2, 8./St.G 2 and 9./St.G 2. The St.G 2 “Immelmann” headquarters was formed on October 15, 1939 at the Köln-Ostheim airfield.
Campaign in Poland – September 1939
During the September 1939 campaign I./St.G 2 operated as part of Fliegerführer z.b.V. Luftflotte 4 from airfields in Częstochowa and Orońsko. On September 1, 1939, at 4.45, twenty one Junkers Ju 87 B-1 of I./St.G 2 took off for their first combat flight from the Nieder-Ellguth airfield. They were led by the squadron’s commander, Maj. Oskar Dinort. Their target was the Rakowice airfield in Kraków. During the mission, Lt. Frank Neubert, piloting aircraft designated T6+GK, scored the first aerial victory for the Luftwaffe shooting down a PZL P.11c flown by the commanding officer of 122nd Fighter Escadrille, Cpt. Mieczysław Medwecki.
II./St.G 2 took part in the campaign against Poland as an independent unit of 1. Fliegerdivision Luftflotte 1 operating from the Stolp-Reiz, Blankenfelde, Frödau, Krasne and Orońsko airfields. During the first combat mission the squadron’s aircraft attacked a coastal battery of 152 mm guns at the Hel Peninsula. One of the Stukas, piloted by Lt. Hamester of 4./St.G 2, while recovering from a dive, hit the surface of the water breaking off the undercarriage legs. Despite the damage, the pilot managed to fly the crippled aircraft to the home base.
III./St.G 2 began its combat operations in the campaign in Poland as part of 1. Fliegerdivision. At noon of September 1, 1939, thirty three dive bombers took off from the Stolp-West airfield to bomb Polish coastal batteries in the area of Oksywie and Redłowo. The unit lost one aircraft. On the second day of the war, the squadron attacked the Westerplatte garrison. I./St.G 2 destroyed a railway station in Piotrków where the Polish Army “Prussia” was unloading its troops.
On September 3, 1939, Ju 87s of III./St.G 2 attacked an aircraft and engine factory and the Okęcie Airport in Warsaw. In the afternoon, dive bombers supported ground units of the German army attacking Polish 8 and 20 Infantry Divisions withdrawing from Mława. Ju 87s also bombed defensive positions in the area of Działoszyn.
On September 6, 1939, I./St.G 2 was relocated closer to the front line to an airfield near Częstochowa and flew several missions against targets in Skierniewice. On the next day, 17 dive bombers, escorted by seven Messerschmitt Bf 109 E fighters of I./JG 76, attacked military installations in Radom.