Staffel of JG 51 under command Oberleutnant Horst Haase was transferred from Orsha on the Eastern Front to Germany.

Gruppe was subordinated to the Geschwaderstab (headquarters unit) of Jagdgeschwader 300 (JG 300—300th Fighter Wing) led by Major Walther Dahl.

Gruppe relocated to Illesheim Airfield located 18 kilometers (11 miles) northeast of Rothenburg ob der Tauber.

Dahl and Moritz drove the attack to point-blank range behind the Liberators of the 492d Bombardment Group before opening fire.

[7] In this encounter, also known as the Luftschlacht bei Oschersleben (aerial battle at Oschersleben), Neumann claimed an Herausschuss (separation shot)—a severely damaged heavy bomber forced to separate from his combat box which was counted as an aerial victory—over a B-24 bomber at 09:42, his 13th in total.

[8] On 20 July, the USAAF sent 1,172 heavy bombers of the Eighth Air Force against railroad infrastructure, airfields and ball bearing factories in central Germany.

Simultaneously approximately 400 heavy bombers of the Fifteenth Air Force attacked aircraft manufacturing in Friedrichshafen and the Memmingen Airfield.

At 11:00 in the area west of Leipzig, Moritz led an attack on bombers of 91st Bombardment Group which they encountered without escorting fighter protection.

Gruppe flew its first combat mission of the month when the USAAF Fifteenth Air Force again attacked Friedrichshafen and Immenstaad am Bodensee, the of the Dornier Flugzeugwerke.

Led by Moritz, the Sturmgruppe attacked the bombers from the rear and claimed 19 aerial victories and Herausschüsse, including a B-24 by Neumann at 11:41.

[10] Later that day at 15:51, Neumann claimed a B-17 of the 1st Bombardment Division attacking railroad infrastructure and fuel factories southwest Germany.

[12] Five days later, the Eighth Air Force sent 219 B-17 bombers of the 1st Bombardment Division to bomb the Luftwaffe airfields at Wiesbaden-Erbenheim, Frankfurt-Eschborn and Köln-Ostheim.

Shortly before noon, JG 3 intercepted a large heavy bomber formation, along with their escorting fighters, in the area of Halle, Dessau, northwest of Leipzig.

[17] Shortly afterwards Oberst Johannes Steinhoff and Generalleutnant Adolf Galland approached him with an invitation to join Jagdverband 44 (JV 44—44th Fighter Detachment).

JV 44 pilots claimed five aerial victories that day, one by Oberst Günther Lützow, another by Steinhoff and three by Neumann.

[20] Following World War II, Neumann reentered military service in the West German Air Force, at the time referred to as the Bundesluftwaffe.

[22] Neumann retired in September 1974 holding the rank of Oberst (colonel) and died on 10 December 2000 at the age of 77 in Altenkirchen, Germany.

[23] According to Obermaier, Neumann was credited with 37 aerial victories claimed in approximately 200 combat missions, twelve of which over the Eastern Front.

On the Western Front, he claimed 19 four-engined heavy bombers and five enemy aircraft flying the Me 262 jet fighter.