Twin engine fighter units
From the spring of 1939 the new code letter system for Kampfverbänden was introduced. The combination of numbers and letters in front of the side cross indicated the appropriate unit to which a particular machine belonged.
With the invasion of Poland on September 1, 1939, fascist Germany unleashed a six-year period of world war. The land, naval and air forces of the two countries competed in an unequal battle. The strategy of the " Blitzkrieg ", supported by an appropriate military force in the service of a monstrous ideology, threw Poland on the brink of extinction. One of the three main components of the German Armed Forces was the Air Force - Luftwaffe.
A clear assessment of the participation, results and intensity of the combat deployment of I./ZG 2 in September 1939 can be misleading. The Polish Fighter Air Force was not qualitatively or quantitatively equivalent opponent. A preliminary report on the experience of Luftflotte 1 fighter units from air combat states: " No experience was recorded in the fight against an equivalent enemy, because Polish fighters did not reach the speed and ascent qualities of the Bf 109 ..."