Leutnant Ettel was posted to 4 staffel, Jagdgeschwader 3 (JG 3—3rd Fighter Wing) on the Eastern Front in early 1942. On 24 June, he claimed his first two victories when he shot down two Il-2 Sturmovik aircraft. He was shot down near Voronezh on 10 July, while destroying a Russian-flown Douglas Boston bomber. He bailed out of his stricken Messerschmitt Bf 109 F-4 "White 1" behind Russian lines, swam across the River Don to return to his unit four days later. He recorded his 20th victory on 9 August and his 30th by 7 October.
4./JG 3 was relocated to the Kuban bridgehead in February 1943, and during the months of intensive operations Ettel claimed some 28 Russian aircraft shot down in March and 36 more in April, including five shot down on 11 April. He claimed his 120th victory on 11 May but was shot down by flak and belly-landed his Bf 109 G–4 between the front lines, returning to German lines despite Russian rifle fire. That same night Ettel led a Wehrmacht patrol to his damaged aircraft to salvage important equipment. He was awarded the Knight's Cross of the Iron Cross (Ritterkreuz des Eisernen Kreuzes) on 1 June.
Wolf Ettel was credited with 124 victories in over 250 missions. Of his 120 victories over the Eastern Front 21 were Il-2 Sturmovik ground-attack aircraft. He recorded 4 victories over Sicily including 2 USAAF four-engine bombers.
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