On 7 May 1942, Hitler issued an order that simple low-speed semi-track load-carrying vehicles be developed for use in the East Bussing-NAG were entrusted with the development of a Zgkw 5 neuer Art which would replace both the 5t and 3t tractors. The first prototypes appeared in the spring of 1943, and production was ordered at a rate of 150 units per month. Only five sWS were delivered in 1943, and 825 of the total order for 7,484 had been completed by March 1945. Most sWS were completed with a lorry type cab, but from mid-1944, an armoured cab was introduced and used for a proportion of the load-carriers and weapon-carriers. A FlaK vehicle was created by mounting a 3.7cm FlaK43 with a 9mm armour shield and fold-down sides, permitting all-round traverse. The weight of the FlaK sWS was 15 tons. A 15cm Panzerwerfer 42 auf sWS (armoured (rocket) launcher) was the replacement for the Maultier based Panzerwerfer. The main advantage of the sWS was increased rocket storage capacity and improved cross-country performance. These units were in action from late 1944. After the war, Tatra in Czechoslovakia built a new version of the sWS known as the Tatra T809.
The sWS differed from other German semi-tracks in having wide dry pin tracks. The suspension layout was similar to that of the Panther tank.
Manufacturer: Bussing-NAG, Ringhoffer-Tatra
Chassis Nos.: 150001-
825 produced from December 1943 to March 1945
Engine: Maybach HL42TRKMS
Gearbox: 2 x 4 forward, 2 x 1 reverse
Weight (tons): 13.5
Length (metres): 6.92
Width (metres): 2.5
Height (metres): 2.07
Speed (km/hr): 28
Range (km): 300