The Germans started experimenting with Night Vision technology in a date as early as 1936.
The first night driving tests by Wa Pruf 8/I occur in 1937. The Army considers the device ludicrously expensive for driving around at night.
Before the war the use of IR sights for gun aiming is discussed with the Army who set its IR sight requirement as the ability to hit bunker embrasure at 1000 meters with a 30cm / 100 watt searchlight. (Searchlight size and power consumption dictates the size/weight and battery life span of the equipment).
IR driving and gun aiming sights were again demonstrated to the Army in 1940, just after the French campaign, fitted to a Panzer I. Here it can be said the military were just uninterested. This subject was not discussed for two years however the Wa Pruf 8/I still continued work on other devices for the military particularly thermal detecting applications for Army coastal artillery.
Summer 1942 the Army came knocking on door of Wa Purf 8/I asking for a way to take on the Russian night time tank attacks (which greatly impressed the Germans). Dr Gaertner shows them the current gear can hit targets at night using a 36cm searchlight out to a range of 300 meters.
The man on the spot at the Wa Pruf General der Artillerie Heinz ZIEGLER (RK; DKiG) decides that range is sufficient and approves development. This is the well know Pak 40 ZG 1221 sight pictured on a Marder II. That shot dates from about November 1942 when firing tests confirm the set-up will work. Development continued and Gaertner notes development on IR in general increases at this point.
However, it was 1943 when one of such devices was finally tested on a Panther tank. It was named “Fahrgerät” (German for “driving equipment”) FG1250 although it was referred to as “Puma” by the allies in the post-war and also known as “Sperber”, a name deriving from the composite “Sperber” units that would be formed by mixing different Night Fighting equipped troops (Vampir, Falke, Uhu and Panthers ).
This equipment comprised an Infra-Red 200-Watt Headlamp and a IR receiver/sight capable of “seeing” in and converting the IR wave length to visible light. It is reported of having a range of up to 500 meters. The set was mounted on a mounting base installed in the commander’s copula and it could be used in a fixed 12 o’clock position traversing with the turret, or unlocked to provide 360° of rotation.
When installed the Commander’s copula, the hatch would not close and the equipment was fed from a battery/generator set installed inside the turret in the place used by the aft right munition rack, with a cost of 3 rounds less in total munition for the main gun.
During daytime the whole equipment would be taken down for protection and installed in a characteristic armoured box in place of the right standard storage bin on the back of the hull.
Such a setup was known as “Solution A” and offered Night Vision capability only to the Commander, the rest of the crew had to rely on his instructions for movement. For targeting the device was locked to the turret’s 12 o’clock position. The Commander would search for targets traversing the turret. Once acquired the crew had to calculate gun elevation by means of a steel “tape” riveted to the IR device mounting base that entered the turret by a small opening. Such a tape would slide up or down depending on the elevation of the IR headlamp/receiver and by measuring the size of the tape the crew would determine the main gun elevation from within the turret. Once everything was in place the shot was ordered by the Commander.
Soon enough a “Solution B” was promptly drafted, allowing the driver to use another set of IR beam/receiver in order to drive the tank under low light conditions, just like it was done with the “Falke”. The “Solution B” is just a fantasy that could maybe only have existed in the very beginning on some training Panther perhaps, but never in active service.
According to the “Germany’s Panther Tank: The Quest for Combat Supremacy” by Tom Jentz,book some 44 Panther tanks and its crews from at least 4 different units were equipped and trained to use Night Fighting gear by the end of WW2, however there are no records or evidence that they were actually used in combat. Interestingly enough some sources state that a trailing “F” was added to the serial number of all of those Panther tanks prepared of mounting Night Vision equipment.
The active units that fought in April 1945 used ONLY the IR-equipment for the commander – BUT one unit (1. Komp. Pz. Rgt 29 ) with 10 IR-Panthers used the – fahrgerät 1253 – for the driver also. He could just simply switch from normal periscope to the F. G. 1253 and use the same “halterung”. The F. G. 1253 was stored beside (on the left) the driver during the day. Nothing was needed to be rebuild outside. He could see the ground with help from the Commander’s spotlight when he had the IR-filter on, or from the light of the UHUs. It is correct that the commander could turn his IR in 360 degrees – the steel band was easy to remove and put on a holder over the periscope guard. Then he could focus on a target and the turret was turning to this position and the commander install the steel-band again, and begins the complicated communication with the gunner that saw nothing outside.
The Allies of course had their own IR and the Germans knew about it, for that reason IR was not used in the west. The British actively looked for IR on the east bank of the Rhine with specially equipped IR Mosquitos before the March crossings, finding none. The British also manufactured and held large numbers of cheap IR detectors close to the front should the Germans deploy their IR.