Panzer I it still performed much useful service against entrenched infantry and other "soft" targets, which were unable to respond even against thin armor, and who were highly vulnerable to machine gun fire. The small, vulnerable light tank, along with its somewhat more powerful successor the Panzer II, would soon be surpassed as a front-line armoured combat vehicle by more powerful German tanks, such as the Panzer III, and later the Panzer IV, Panzer V, and Panzer VI; nevertheless, the Panzer I's contribution to the early victories of Nazi Germany during World War II was significant. Later in that war the turrets
AI Mk. VIII radar of the set without the pilot's indicator was sent for testing to the FIU in Mosquito "HK946" in December 1943, and returned some time later with an extensive list of upgrade suggestions. The idea of windscreen projection had been attempted with the AI Mk. IV as the Mk. V, but a number of problems had been found and it was not adopted for service. Several updated versions were used in trials, but by 1943 the Mk. V radar was obsolete, and the "Pilot's Indicator Display" (PID) was instead adapted to the Mk. VIII. This time the system's output was not