In 1940 the Luftwaffe leadership made a decision to carry out their program for military airport network development.
As a result, two airports were built on Polish soil in the vicinity of the already used landing grounds. They were the units in Rudniki north of Częstochowa and Zendek located 30 km west of Zawiercie and 16 km north of Będzin. In Rudniki the Luftkriegeschule IX was established, which was in use from November 1940 to July 1944. Next, the Segelfliegerschule der Luftwaffe Tschenstochau was established where glider training was carried out using a towline machine. This unit was not very big - much smaller than the airport in Zendek. It occupied the area which now forms the northern part of the International Airport in Mierzęcice-Pyrzowice (Katowice Airport).
The airport in Zendek featured a very wide runway. The surface of the runway, which was going in the EW direction, was made of basalt/asphalt. The airport was designed for the anti aircraft defence units of the Upper-Silesian Industrial Region. It's functionality was twofold: as a spare airport and as a stage airport for flights from the Reich to the eastern front and back. The airport was called Udetfeld after the tragic death of a renowned German airforce personage - Ernst Udet.
In the beginning of 1944 the airport was equipped with technical backup devices to handle rocket drive aircraft Me 163 Komet. In the summer of the same year a training centre was established, which was separated from the Erpobungskommando 16 (16. Experimental Unit) in Bransik near Leipzig. In the beginning the unit in Mierzęcice was known as Erganzugstaffel JG 400, that is as an additional fighter regiment 400. The regiment's commanding officer at the time was captain Robert Olejnik. In September 1944 the 13th and 14th squadrons, as well as the germ of the 15th squadron were formed. Leutenant Adolf Niemeyer was the comanding officer of the 13th squadron and Leutenant Mano Ziegler of the 14th.
The students were young boys who had completed the SG 38 Grunau Baby and DSF Karnich glider towline training programs and a special training program in the Glenhausen Centre. It was there that the trainee pilots were taught to fly the fast DSF Habicht gliders. Initially the training was carried out on standard 13.3m wingspan gliders and later on 6.0m wingspan Stummer Habicht gliders. The latter model featured high flight and landing speed - similar to the formerly mentioned Me 163. The training program in the 13th and 14th squadrons was based on completing several flight sessions on the Me 163 engineless, ballast loaded glider versions, towed to the release altitude by the Bf 100C. Next, there were trainee flights on the 163A-0 with a working engine.
The following flights were combat ones on the 163B, initialy glider type with a empty tank, later with the water-filled tank and finally featuring sharp take-offs with a working engine. Thanks to this kind of training each squadron was able to train about 90 pilots within a month. The length of the training program was later reduced as a result of shortages in rocket fuel supplies. At that point a young trainee pilot was put in the heavy 163B with a water-filled tank. Parallek to the training programs, some flight technology development projects were carried out on Udetfeld. A new aiming device to be put on the Me 163 and Me 262 was being tested, as well as one Me 163A-0 machine was modified to carry rocket missiles by mounting under each wing 12 rail rocket launchers for unguided, 55mm calibre, air-air rocket missiles type R-IVM. Even though this kind of design certainly influenced the flow around the wings, it did not cause any adverse effect on the aircraft flight characteristics. All of the above mentioned testing was done in Mierzęcice in the autumn of 1944.
The Me 163A-0 tested on Udefeld was the first rocket drive fighter in the world to be equipped with this kind of weapons. Several months after these tests the same kd of weapons were installed on 12 Me 163B fighter machines, but they failed to play any significant role in combat. In the view of the approaching eastern front the flights were evacuated to Szprotawa towards the end of December and later to Brandis near Lepzig where they witnessed capitulation. When the Germans were leaving the airport in January 1945 they destroyed the Zendek-Mierzęcice airport and all of its facilities. Explosives were placed at regular intervals on the runway and detonated to make deep craters. After the war those craters were filled and the whole runway fixed. The traces of these damages, however can be seen to date.