At the time of Unger's posting to JG 3, IV.
Gruppe was commanded by
Major Franz Beyer and was fighting in
defense of the Reich. On 26 February, just after the
United States Army Air Forces (USAAF) and the
Royal Air Force (RAF)
Bomber Command finished "
Big Week", IV.
Gruppe moved from
Venlo in the Netherlands to
Salzwedel in central Germany. At Salzwedel, the
Gruppe was joined by
Sturmstaffel 1, headed by
Major Hans-Günter von Kornatzki. The
Sturmstaffel was an experimental unit flying the so-called
Sturmböcke (battering ram) up-gunned
Focke-Wulf Fw 190 A-7 and A-8 aircraft.
In defense of the Reich On 11 April, Unger claimed his first aerial victories. At the time Unger was assigned to 11.
Staffel of JG 3, the
Staffel was commanded by
Oberleutnant Otto Wessling. That day, the USAAF attacked the German aircraft industry in
Oschersleben,
Bernburg,
Sorau,
Cottbus and
Arnimswalde, present-day Goleniów, with 917
heavy bombers escorted by 819 fighter aircraft. The
Gruppe was
scrambled at 10:05 with the order to unite with other Luftwaffe units of the
1. Jagd Division (1st Fighter Division) and
3. Jagd Division (3rd Fighter Division) over the
Brocken. Between 10:00 and 10:30, the Luftwaffe fighters intercepted the USAAF bombers between
Braunschweig and
Halberstadt. During this aerial battle, Unger claimed a bomber shot down. Because the claim was not witnessed, he was not credited with the aerial victory. Following this mission, the Luftwaffe fighters were refueled and rearmed and were scrambled a second time at 12:40. The returning bombers were intercepted south of
Rostock. Flying his fourth combat mission of the war, Unger was credited with a
Boeing B-17 Flying Fortress shot down. of the
492d Bombardment Group after the aerial battle at
Oschersleben on 7 July 1944 Two days later, the USAAF
Eighth Air Force attacked the ball-bearing factories of
Schweinfurt, the
Messerschmitt factory at
Augsburg, the
Dornier factory at
Oberpfaffenhofen and the Luftwaffe
Lechfeld Airfield. IV.
Gruppe attacked the third wave of bombers near
Aschaffenburg in a frontal attack. During this attack, Unger shot down a B-17 bomber. On 15 April,
General der Jagdflieger Adolf Galland visited IV.
Gruppe at Salzwedel and announced that the
Gruppe was to be converted to a
Sturmgruppe following the example of
Sturmstaffel 1. In consequence, the
Sturmgruppe was placed under the command of
Hauptmann Wilhelm Moritz and 11.
Staffel was merged with the experimental
Sturmstaffel 1 and renamed to 11.
Sturmstaffel and placed under the command of
Oberleutnant Werner Gerth after Weßling was
killed in action on 19 April. On 18, the USAAF Eighth Air Force headed for industrial targets near
Berlin. The USAAF
3rd Bombardment Division was intercepted in the area
Rathenow and
Nauen. During the course of a 20 minutes aerial battle, Unger claimed two B-17 bombers shot down. The following day, the USAAF Eighth Air Force attacked the German aircraft manufacturing and aircraft engine industry as well as various Luftwaffe airfields in
Westphalia and
Hesse. IV.
Gruppe took off at 09:30 and met up with the other two
Gruppen of JG 3 near
Göttingen and
Kassel. During this mission, Unger shot down a B-17. The USAAF Eighth Air Force sent 803 heavy bombers to attack transportation infrastructure in western Germany, including the
marshalling yard at
Hamm. IV.
Gruppe was scrambled at 18:20 and intercepted the bombers of the
2nd Bombardment Division at 19:40. In this encounter, the four aerial victories. This number includes an
Herausschuss (separation shot)—a severely damaged heavy bomber forced to separate from its
combat box which was counted as an aerial victory—over a
Consolidated B-24 Liberator bomber. On 24 April, the USAAF sent its bombers to the German aircraft industry located in southern Germany. At 13:30, Luftwaffe units intercepted the bombers west of
Munich. In this encounter, Unger was credited with an aerial victory over a B-17 bomber. The USAAF Eighth Air Force flew its next daylight mission on 29 April, attacking Berlin with 679 heavy bombers of which 618 reached the target area. IV.
Gruppe was scrambled at 10:10 and the bombers were first sighted in the area of
Magdeburg. Although the bombers were protected by escorting fighters, IV.
Gruppe flew two frontal attacks. The Luftwaffe pilots claimed twelve aerial victories and nine
Herausschüsse, including one by Unger, for the loss of five Fw 190 fighters damaged in combat. In May 1944, the Luftwaffe experimented with rearwards firing
Werfer-Granate 21 rocket-propelled mortars, also known as the (Crab Device). The idea was that the pilot would first fire his forward facing weapons against the bomber, followed by firing a time-delayed mortar after passing the bomber formation. In total, 20 Fw 190 A-8 fighter aircraft were fitted with the on the orders of Galland. While based at
Barth, Unger was one of the pilots who tested the , reporting that the weight of the device further deteriorated the performance of the heavily armored
Sturmbock variant of the Fw 190 in both speed and maneuverability. On 8 May 1944 he was shot down by defensive fire from one of the B-17s, but managed to make a
gear-up landing in his
Messerschmitt Bf 109 G-6 at
Uelzen. Awarded the
Honor Goblet of the Luftwaffe () on 21 June 1944, Unger hit two
B-24 Liberator over the town of Oschersleben on 7 July 1944, claiming his 10th and 11th victories. In total, Luftwaffe pilots claimed the destruction of 60 bombers while actual losses were 28 bombers destroyed and further bombers returned with various levels of combat damage. The authors Prien, Stemmer and Bock state that the consolidated attack flown in close formation by the
Sturmgruppe resulted in
overclaiming of aerial victories caused by the confusing combat situation. During these attacks, multiple pilots may have simultaneously fired at the same bomber. It was therefore unclear who was responsible for the destruction of the bomber. On 3 August 1944, he shot down two further B-24s, but his Fw 190 A-8 was hit again, forcing him to abandon his aircraft. In August 1944 Unger vas awarded the
German Cross in Gold. On 23 October 1944, when he had accounted for a total of 19 four-engine bombers,
Fahnenjunker-Oberfeldwebel Unger was awarded the
Knight's Cross of the Iron Cross (). In December 1944, Unger was promoted to
Leutnant (second lieutenant).
Eastern Front and end of war On 12 January 1945, Soviet forces launched the
Vistula–Oder offensive advancing into
German-held territory, capturing
Kraków,
Warsaw and
Poznań on the
Eastern Front. In consequence, on 21 January, IV.
Sturmgruppe was ordered to relocate from
Gütersloh Airfield to
Märkisch Friedland, present-day Mirosławiec, located approximately east of
Stargard. With this transfer, the
Sturmgruppe came under the control of the
1. Flieger-Division (1st Air Division), commanded by
Generalmajor Robert Fuchs, and subordinated to
II. Fliegerkorps (2nd Air Corps), headed by
General der Flieger Martin Fiebig. The following day, Unger was appointed
Staffelkapitän (squadron leader) of 14.
Sturmstaffel of JG 3, succeeding
Oberleutnant Karl-Heinz von den Steinen who was transferred. On 27 January, Märkisch Friedland had to be abandoned and the
Sturmgruppe retreated to an airfield southwest of Stargard. Over the next weeks, the
Sturmgruppe predominantly flew
fighter-bomber missions in support of German ground forces retreating towards the
Oder. On 19 February, the
Sturmgruppe flew ground support missions south of Stargard near the Oder. During this mission, Luftwaffe pilots claimed five aerial victories, including a
Bell P-39 Airacobra fighter aircraft by Unger. On 15 March, the
Sturmgruppe flew multiple combat missions to combat area near
Stettin. During these missions, Unger shot down two
Petlyakov Pe-2 bombers. On 2 April, Unger left for
Brandenburg-Briest when he was transferred to
Jagdgeschwader 7 "Nowotny" (JG 7—7th Fighter Wing) operating the revolutionary
Messerschmitt Me 262 jet fighter without claiming further aerial victories. He was succeeded by
Leutnant Herbert Bareuther as commander of 14.
Sturmstaffel of JG 3. ==Later life==