Endurance Main Battle Tank

Endurance Main Battle Tank
Endurance MBT of A Squadron, 24th Mounted Volunteers
Place of origin	Arthurista
Service history
In service	1965-present
Used by	Commonwealth Army, Eagleland Army Madrastan Army, Keralam Army
Production history
Manufacturer	Arthuristan Dynamics
Produced	1964-1979
No. built	4,000 units
Specifications
Weight	60 tonnes
Length	10.6m (gun forward)
Width	3.66 m
Height	2.9 m
Crew	4
Armor	Cast steel and rolled homogeneous steel, applique composite armour (Mark 2 and 3 only), explosive reactive armour (Mark 3 only)
Main armament	120mm L/52 rifled cannon
Secondary armament	L6V co-ax, M2 Browning, pintle mount for machine gun
Engine	Arthuristan Motors AVE-2 V-12 turbodiesel (Mark 1) Arthuristan Motors AVE-A3 V-12 turbodiesel (Mark 2) 800 kW
Transmission	Hydropneumatic
Operational range	550km on road
Speed	55 kph on road

The Endurance Main Battle Tank is an Arthuristan main battle tank. It was conceived as a successor to the Cavalier. The Endurance entered service in 1966, and was in turn gradually replaced by the Boudicca Main Battle Tank in the 1980s-90s in active service. Considerable numbers are retained in the Commonwealth Army's mobilisation reserve stock.

History and design

It was designed with the armoured warfare doctrine of the Commonwealth Army of the 60s in mind - to stop an enemy advance at a pre-determined line, then push them back in a measured counterattack. The design thus called for a powerful main gun, able to disable contemporary armoured threats at very long range, as well as high levels of armour protection, up to 400mm RHA-equivalency taking into account the sloped shaping of the vehicle's frontal arc. It also incorporated what was for the era an advanced fire control system based on an optical range-finder, which replaced the 12.7mm ranging gun of the Cavalier. By contrast, mobility received little attention. As a result, the Endurance became known as "the tortoise" in Arthuristan service, heavy, expensive, slow and sometimes mechanically unreliable, but beloved for its firepower and survivability, a reasonably good match against the Type-65 and Type-73 favoured by rival armies of the period. Due to its cost, it only fully replaced its predecessor, the lighter Cavalier, just before the Boudicca was about to entered service in the early-80s.

Upgrades

The Mark 2 was introduced in 1976. It featured the first Arthuristan composite armour design: "Rowan" applique plates which were attached to the surface of the turret and the glacis, consisting of a laminate of rubber and triple-hardened steel. With it, the Endurance's resistance against HEAT rounds was approximately equivalent of 600mm of RHA, or 450mm against KE munitions. The tank received a new fire-control system with a laser rangefinder, replacing the mechanical optical range-finder, allowing for a faster engagement cycle against distant targets. It was also tri-axially stabilised to allow for accurate firing on the move and linked to an early fire control computer system.

The Mark 3 upgrade of 1984 incorporated many advanced features developed for the Boudicca project. The most important improvement was the fire control system. The gunner and commander received passive thermal sights, which replaced the earlier IR-illuminator. All of them these sensor modules tie into the vehicle's new Pythagoras Digital Ballistics Computer, which could take into account data such as range, movement speed, barrel wear, wind speed and other trajectory-affecting factors to maximise first-shot accuracy. Protection was enhanced with Rowan 2 applique modules on the turret front and glacis, comprised of a laminate of rubber, triple-hardened steel and titanium, as well as explosive-reactive armour bricks. Unlike the ERA of most main battle tanks, these blocks are installed virtually without gaps between them, allowing them to provide up to 30% more resistance towards KE munitions and 70% versus HEAT.

The Mark 4 upgrade was initiated in the early-90s for tanks in the Commonwealth Army's reserve stock. In addition to the improvements contained in the Mark 3 package, the tank's main gun was also re-breeched so it would accept one-piece ammunition designed for the Boudicca's L42A2 main gun, including the ASTAM (Arthuristan Smart Top-Attack Munition), a gun-launched precision-guided round.

The Endurance is the most numerous MBT in service with the Madrastan Army. Madrastan imported its first batch of Endurance tanks in the late-60s and procured a domestic production license in the early-70s and as of the mid-2010s most have been upgraded to the Mk 3 standard. The most modern of Madrastan's main battle tanks, the Kaurava, combines the Endurance's hull and main gun with a new up-armoured turret and a more powerful and mechanically reliable powerpack.

Keralam received 360 second hand Arthuristan Endurance MBTs, as well as engineering, bridge-laying and recovery vehicle variants as a replacement for their obsolete Cavaliers in the late-90s as part of an Arthuristan defence assistance program. These tanks were upgraded to the Mark 3 standard and received new turbodiesel engines before delivery.