- Meimberg joined JG 2 "Richthofen" in December 1939. He claimed his first two victories during Battle of France, when on 19 May 1940 he shot down Hurricane fighter and another on 3 June 1940, when the victim was a P-36 Hawk fighter.
- Meimberg during the Battle of France flew as wingman to Hans "Assi" Hahn (108 wins). During the Battle of Britain Meimberg become the Flying ace when he shot down other four enemy planes, including three Spitfire fighters. He flew with Helmut Wick (56 wins) on the day that he was fatally shot down over the Isle of Wight.
- On 30 July 1941 was Meimberg awarded for 15 victories the Ehrenpokal der Luftwaffe and on 29 October 1942 the German Cross in Gold.
- In February 1943 was Meimberg transferred to JG 53. In 1944 Meimberg was appointed Gruppenkommandeur II./ JG 53. Finally, on 24 October 24, 1944 Meimberg was awarded the Knight's Cross of the Iron Cross.
- On 26 December 1944 he claimed victories 48, 49 and 50, all P-47 fighters in the Ardennes sector, just before being shot down himself. Meimberg was shot down again 26 December 1944 in Bf-109 G-14 Werk # 166297 "Yellow 1" and bailed out over Schaichhof after engaging American fighters over Stuttgart.
- He missed Operation Bodenplatte since he was hospitalized after the Operation of 26 December. He scored his last victory over Spitfire fighter on 13 April 1945.
- During his successful career he achieved 54 victories in 250 combat missions, all of them over the Western Front. He claimed 20 Spitfires, 12 P-47 Thunderbolt fighters and four four-engined bombers.