Strv 103

The stridsvagn 103 (strv 103), also known as the "S-Tank", is a Swedish post-World War II main battle tank, designed and manufactured in Sweden by Bofors AB (and to some extent Landsverk AB). It was developed in the late 1950s to the mid-1960s and was the first main battle tank to use a turbine engine, as well as the first, and so far only, service tank to not feature a turret. While some might argue that the S-Tank is not a tank, or that turretless casemate vehicles can't be called tanks, it is a fact that the S-Tank was designed as, deployed as, and used as a tank by the Swedish army. Besides lacking a turret, it was the first tank with a fixed main gun, meaning that the gun was fixed in the hull on both the X-axis and Y-axis. To aim the gun horizontally, the entire vehicle had to be steered side to side. To aim vertically, the tank used a new type of controllable suspension, probably also a first in the world, that allowed the tank to tilt forwards and backwards using gas-hydraulic hydropneumatics.

Besides tanks, the chassis was also used for other AFV projects, such as the Bkan 1C Self-Propelled Artillery Gun (SPAG) and VEAK 40 Self-Propelled Anti-Air Gun (SPAAG).