The Stridsvagn 103 tank, as odd as it looks, despite being the main battle tank, but its main gun is completely fixed, because it has no turret
The Stridsvagn 103, also known as the S-Tank, is a mid-1950s Swedish design
Its primary criterion was crew survivability
Although Sweden did not have much experience in making main battle tanks, from statistics during World War II and the Korean War
the Swedes believed that most of the tank's losses were due to turret hits
To reduce this risk, the height of the tank had to be reduced, and it was best to get rid of the turret
The Swiss designers created the Stridsvagn 103 tank, a tank without a turret, the lowest-profile main battle tank ever built
The Stridsvagn 103 is only 2.13 meters high, and if include the height of the machine gun it is only 2.43 meters high
the barrel centre when horizontal is just 1.7 m.
It weighs about 40 tons, and width is about 3.6m
The Strv 103 is undoubtedly the toughest tank to hit, but its main gun is permanently attached to the hull
so it cannot function as other traditional tanks
So how does the gunner aim at the target?
All Strv 103s were fitted with a dozer blade for which to dig out earth
To aim, it requires the entire vehicle to be turned to face the enemy
Tanks are often deployed in hull-down firing positions, either behind dug entrenchments or using the crest of a hill
in order to reduce the exposure of the vehicle to enemy fire
Since the Strv 103 orients the entire tank to depress and elevate the barrel
in a hull down position it has very little apparent height and subsequent visual profile to the enemy
It could also lower the hull a further 13 centimetres by adjusting the suspension
Although the main gun's aim had been resolved, since it was permanently mounted
it was not possible to install horizontal and vertical stabilization systems for the gun
the technologies the Swedish designers had miscalculated and couldn't fix
As a result, the tank could not accurately move and fire at the same time
but the Swedish experience with Centurions suggested that, in order for tanks to reach acceptable accuracy
The original design of the Stridsvagn 103 required only a crew of two, the driver and the gunner
This design contrasts with most tank designs of the time, which had a crew of four people, the driver, gunner, loader, and commander
In theory, a crew of two is entirely possible, but the reality of fighting like repairing
setting up camps and receiving ammunition would be very difficult for a crew of only two members
On later versions, the Strv 103 added a radio operator cum rear driver.
But why does the vehicle have a rear driver?
Because Stridsvagn 103 has not only one, but two driving positions
This allowed the tank to be driven backwards at the same speed as forwards
keeping its frontal armour pointed at the enemy, while relieving the commander of routine radio duty
The commander and gunner/driver both had the same set of sights and controls to fire the gun and drive the tank
Although the Stridsvagn 103 has gone through several engine configurations
the last and most powerful is the 6V53T Detroit diesel engine, with 290 hp
and the addition of a 490 hp Caterpillar 553 gas turbine engine, to Grants additional powers when needed
Stridsvagn 103 can reach a top speed of 60 km/h, and a range of 390 km
Main armament of the Swedish tank was the 105mm Bofors L/62 rifled gun
This was coupled to two fixed 7.62mm KSP 58 machine guns with an optional KSP 58 MG serving as an Anti-Aircraft measure
The main gun was mated to an auto-loading feature which allowed the crew number to be kept to a minimum
With such a low profile and a fixed gun, the Strv 103 is more suitable for defensive operations than for attacking operations on the battlefield
The Stridsvagn 103 has also never been in combat, and as such, its design has yet to prove effective on the battlefield
However, for its intended role in the 1960s, it had a lot of advantages
Stridsvagn 103 has been tested in the US, Norway and UK
It showed, it would probably do well in combat, and in some cases, would outperform the old NATO main battle tanks