In early October 1944, III./JG 77 received their first Bf 109 K-4 and during the month no fewer than 75 of the type were delivered. After a period of rest and refit the Gruppe was involved in pilot training up to 2 December when they flew their first combat mission. This mission was a failure because the Geschwader received contradicting course instructions from the control center, and as a consequence took-off too late to make contact with the enemy formation.

However on 23 December 1944, while flying over the Ardennes in support of the German attack in the west, there would be enemy contact. During the four previous days the Gruppe was unable to fly over the battlefield due to poor weather. However as the weather cleared up this day, III./JG 77 was conducting fighter sweeps and attacking the enemy fighter-bombers.

It is not know that "White 17" was an assigned aircraft of Uffz. Munninger in November however what is known is that he would lose his life in this machine on 1 January 1945 during the Bodenplatte attack on Allied airfield, this attack by the Luftwaffe was also in conjunction with the German trust in the west, the Ardennes offensive. Thereby was Heinrich Munninger one of the many anonymous men and even boys victimes, with family, friends or relatives, who were just caught up in this war.

According to III./JG 77 loss statistic The K-4 flown by Munninger was hit by AA fire over the RAF airfield at Antwerp-Deurne (B.70), near Tilburg and crashed killing its 21 years old pilot. This airfield was the main target for JG 77 this day and here the Germans found a very large number of targets. But according to RAF "they only managed to destroy 12 Spitfires in a very ineffective attack". To this another two Spitfires was added, lost in air-combat. This all for a loss of 11 JG 77 pilots from the 59 involved.

Note that the camouflage of this Bf 109 K-4 is consistent with the early pattern camouflage scheme and colors of machines manufactured by Messerschmitt Regensburg GmbH during the August-October 1944 period. The first 400 machines produced showing the RLM 76 with yellowish green tint, a result of using the wrong formula when mixing the Light Blue underside color. Note the Gruppe badge on the engine-cowling, with its yellow-outlined heart, characteristic of III./JG 77.