Born in Mühlheim am Main in the German Empire, Weissenberger, who had been a glider pilot in his youth, volunteered for service in the Luftwaffe of Nazi Germany in 1936.

Weissenberger, the son of a plant nursery owner, was born on 21 December 1914 in Mühlheim am Main in the Grand Duchy of Hesse of the German Empire.

[2][Note 1] As a glider pilot with the German Air Sports Association (Deutscher Luftsportverband), he made his maiden flight on 16 November 1935.

Germany regarded its operations in the region as part of its overall war efforts on the Eastern Front, and it provided Finland with critical material support and military cooperation.

[1] Weissenberger claimed his first aerial victory, a Polikarpov I-153 biplane fighter, on 24 October 1941 and was awarded the Iron Cross 2nd Class (Eisernes Kreuz zweiter Klasse) on 6 November 1941.

On 24 January 1942, Weissenberger and Oberleutnant Max Franzisket flew on a ground attack mission against the Kirov Railway line.

[Note 3] Weissenberger claimed a Polikarpov I-18 shot down at 13:35, roughly 4 kilometers (2.5 miles) northwest of the railway station of Bojaskoje.

[1] Weissenberger became an "ace-in-a-day" for the first time on 10 May 1942 when he shot down five enemy aircraft, aerial victories 14–18, between 16:45 and 16:57 while on a Ju 87 escort mission.

These victories were claimed over aircraft of 2 Gvardeyskiy Smeshannyy Aviatsionny Polk (2 GSAP—2nd Soviet Guards Composite Aviation Division), which lost ten Hurricanes destroyed and three damaged.

Weissenberger took off on his first Bf 109 combat mission at 14:00 on 15 September 1942 after he had spent a few days familiarizing himself with the single-engine fighter aircraft.

The flight encountered enemy aircraft and Weissenberger filed claims over two Curtiss P-40 Warhawk Lend-Lease fighters shot down at 14:31 and 14:33.

On his second mission, which began at 15:00, he encountered a formation of roughly 30 aircraft, claiming four Hurricanes shot down from 15:49 to 15:56, a time space of seven minutes.

Weissenberger claimed three P-39s shot down during this mission, but was himself hit by anti-aircraft fire and had to make a forced landing in his Bf 109 G-2 (Werknummer 13912—factory number).

The heaviest fighting occurred on 22 June over the Karelia Front, during which his Staffel claimed 13 victories, of which three were Hurricanes shot down by Weissenberger.

Gruppe was subordinated to Luftflotte 2 (2nd Air Fleet) in the middle sector of the Eastern Front in support of the defensive battles at Vitebsk.

Gruppe relocated again to Polotsk and then to Jakobstadt, present-day Jēkabpils in Latvia, and on 16 March Weissenberger claimed his 141st victory.

The ground personnel were flown on Junkers Ju 52s to their airfield at Montdidier, 35 km (22 mi) south of Amiens.

At 07:02 Weissenberger shot down his third P-47 of the day but his Bf 109 G-5 (Werknummer 110256) was hit in the engine forcing him to bail out near Saint André.

The constant attacks against German airfields forced another move in July 1944, this time to Frières in the vicinity of Laon.

Gruppe flew a combat air patrol on 6 July 1944, resulting in the claim of three Lockheed P-38 Lightnings destroyed.

The Gruppe was given a few days of rest and on 13 July were ordered to operate against enemy fighter bombers attacking German positions in the area Rouen – Bernay – Évreux.

Flying at a height of 10 meters (33 feet), Weissenberger managed to shoot down one Spitfire 5 km (3.1 mi) south of Bayeux.

Jagdkorps (2nd Fighter Corps), Generalleutnant Alfred Bülowius, accompanied by Oberstleutnant Herbert Ihlefeld inspected II.

On 17 July, Weissenberger led his Gruppe on a number of missions in the combat area near Caen without encountering any enemy aircraft.

In the ensuing aerial encounter at an altitude of 3,800 m (12,500 ft), Weissenberger shot down a Spitfire 15 km (9.3 mi) south of Rouen.

At Kaltenkirchen, he was given command on 25 November of the newly forming I. Gruppe of Jagdgeschwader 7 "Nowotny" (JG 7—7th Fighter Wing).

Nowotny, a fighter pilot credited with 258 aerial victories and recipient of the Knight's Cross of the Iron Cross with Oak Leaves, Swords and Diamonds (Ritterkreuz des Eisernen Kreuzes mit Eichenlaub, Schwertern und Brillanten), had been assessing the Messerschmitt Me 262 jet aircraft under operational conditions.

On 12 November 1944, the Oberkommando der Luftwaffe (OKL—Air Force High Command) ordered JG 7 "Nowotny" to be equipped with the Me 262.

On 18 March 1945, JG 7 "Nowotny" claimed 25 aerial victories over Berlin, among them three Boeing B-17 Flying Fortresses shot down by Weissenberger.

Weissenberger survived the war and was credited with a total of 208 aerial victories, including 33 over the Western Front, claimed in 375 combat missions.