Kingdom of Sweden (1998)
Light Tank – Unknown Number Built
The CV90120 is a prototype light tank that has undergone continuous development since its first appearance in the summer of 1998 at the EUROSATORY defense exhibition in Paris. However, attempts to mount higher calibered guns on the CV90 can be traced back to 1993, when Hägglunds collaborated with GIAT to make the CV90105 TML, which was equipped with a GIAT Industries TML 105 turret. The initial development on the CV90120 was presumably started by Hägglunds AB and continued when Alvis Ltd. purchased the company in 1997. Development continued under the guise of BAE Systems, which acquired Alvis Ltd. in 2004, Hägglunds included.
Development
The reason behind the development of the CV90120 was to give Sweden an option to equip a lighter vehicle with the firepower of a main battle tank, equivalent to the Leopard 2/Strv 122s. Northern Sweden has very few roads and difficult terrain, both during summer and winter, and the CV90 had already been designed with these conditions in mind. This paved the way for the CV90120’s addition to the CV90 family, combining extreme mobility with extreme firepower, but at the cost of comparatively light armor.
The initial prototype of the CV90120 had a brand new welded turret to accommodate a large caliber tank gun. Externally, the chassis was completely identical to a normal CV90, retaining the same engine, suspension, and internal layout. However, it was modified to accommodate the increased weight of a larger turret, carrying a larger caliber gun. This prototype vehicle weighed around 20 tons.
The vehicle itself has had several iterations across development, stretching from 1998 to 2011. These are distinguished into 3 major forms, starting with the CV90120 Prototype, the CV90120-T marketed vehicle, and later, more complex variants like the CV90120 Ghost.
Prototype Specifications
The CV90120 prototype was extremely light for its firepower, sitting at 20 tons when empty. The low mass came with several challenges. The most prominent was making such a light vehicle stable enough to handle the forces produced by the firing of a powerful gun. The 120 mm gun’s origins can be traced back to Switzerland, being a development that was made possible by using steel with increased strength. This also comes as a design challenge to the vehicle itself, as the recoil energy is transferred to the chassis.
The driver is placed in the lower left front of the chassis, alongside the engine. The turret has a complement of 3 crew members, consisting of a gunner, a commander, and a loader. The rear of the vehicle, which was originally used for carrying soldiers, has been turned into ammunition storage.
Firepower
The chosen gun was the CTG (Compact Tank Gun) 120/L50 smoothbore, a lightweight gun developed by RUAG Land Systems. It was light enough not to hinder the vehicle’s mobility and had low enough recoil force to avoid damaging the vehicle itself. It came with a bore evacuator and a muzzle brake. The gun was designed to accommodate all current and future NATO 120mm ammunition, which were considered more than sufficient to combat threats at that time. The vehicle’s elevation/depression was -8 degrees to +22 degrees. The muzzle velocity when firing the German-developed DM33 APFSDS shell was 1,680 m/s.
The new turret also featured a bustle mounted semi-automatic loader, allowing this light tank a rate of fire between 12 and 14 rounds per minute with an experienced crew. The ammunition is stored with a protective wall separating the crew from the autoloader in case of ammunition detonations or ‘cook-offs’. The semi-automatic loading device was capable of carrying 12 ready-rounds, while 33 rounds are stowed in the lower rear hull. The turret also featured 12 Galix Smoke grenade launchers.
The fire control system is a Saab UTAAS computerized Universal Sight and Fire Control System, accompanied by an Avimo DNGS Thermal Sight. These provided the gunner with a reliable way of hitting the targets with day and night optics and a laser rangefinder.
The prototype did not feature any lighter weaponry such as machine guns.
Protection
The vehicle is designed to have a minimally armored hull made of steel to accommodate externally mounted modular armor. These armor packs varied heavily, from composite materials to high hardness steel. The vehicle was developed to have applique and armor packs mounted externally, as testing revealed that add-on armor gave better protection per kilo compared to armor steel. However, unfortunately, the thickness of the base armor is unknown. No further information about the protection offered by the add-on armor packages is available.
Optics
The vehicle commander had access to an early version of the Saab Lemur Panoramic sight, which has appeared in multiple iterations over the years. It gave the vehicle commander access to laser rangefinding and the ability to operate in a ‘hunter-killer’ mode. The Lemur could also be used as a Remote Weapons Station to give the vehicle a machine gun.
This Lemur commander’s optics have appeared in multiple variations over its many years of development, in different modular compositions and technology levels as development progressed. It appeared on the first prototype and the updated CV90120-T.
The gunner’s sight provides the gunner with between x3 and x10 magnification. The driver’s view is almost 180 degrees.
Engine & Mobility
The CV90120’s engine was a Scania DI-16 800 horsepower diesel engine, giving the vehicle a maximum speed of 70 km/h on roads, and 40 km/h in reverse. It was designed with excellent mobility in mind, despite its reinforced chassis and newly designed turret. The engine was placed in the front right of the hull, and will also function as protection in the case of penetration from the front, much like the Israeli Merkava design. If needed, the engine could be uprated to accommodate higher horsepower demands, showing modularity similar to other aspects of the vehicle. The gearbox chosen was an Allison Perkins X-300-5 Automatic gearbox with 4 forward and 2 reverse gears.
The running gear has 7 paired road wheels per side, forward sprocket wheel, and rear idler wheel. The tracks were made of steel with rubber pads. The suspension is torsion bar based with rotary dampers and no return rollers. The vehicle’s range was 600 kilometers on a full tank. It could cross slopes with a 60% gradient and has a fording of 1.5 m. All of these characteristics have been designed due to the obstacles of the Scandinavian peninsula, where a vehicle might have to go from snowy mountains to muddy wet forests, as the northern terrain varies a lot and the infrastructure there is generally underdeveloped in large regions.
Other
The prototype also worked as a testbed for several different systems for passive protection, including a water-vapor dispensing system to clear out any thermal signature externally on the vehicle. By 2001, the vehicle had completed its initial development cycle and left the prototype phase.
CV90120-T
With BAE Systems purchasing up Alvis Ltd. in 2004, the development of the vehicle became even more ambitious than before, revealing the vastly modernized CV90120-T in 2007 to the international military market.
The CV90120-T was another developmental cycle for the CV90120 that focused more on the internals and alternative protection systems that replaced the necessity to put on external armor to counter threats. This was defined by a heavy emphasis on electronics and definable ‘soft-kill’ defense systems.
Internal Changes
The vehicle featured vastly more advanced electronics systems. These systems might be referred to as ‘soft-kill’, as they impact a crew’s capability of preventing the loss of the vehicle by warning the crew before a shot has even been fired. Among these qualities of life improvements, a large sensory system covering the vehicle’s turret stands for most of its electronic early warning system.
These sensors can detect lasers from hostile laser rangefinders and detect missiles heading to the vehicle’s position. The vehicle also features a top-attack radar, warning of high angle munitions that might be a danger for the vehicle. The vehicle also features an advanced Battle Management System for modern battlefield situations.
The vehicle also improved internally with the latest modularity and customization present for potential customers. The CV90120-T could use different types of CV90 chassis from 1998 to today. This means that, while initially, the weight of the prototype was 20 tonnes, the development of the chassis and its internals improved by each generation developed by Hägglunds. Today, the vehicle can reach weights of 40 tonnes without any repercussions on mobility.
External changes
Externally, not much changed. The CV90120-T received a new type of bore evacuator for its 120 mm CTG L/50 and the prototype had externally mounted smoke launchers. These were removed when the smoke launchers were incorporated into the sides of the turret bustle, allowing less external clutter while improving external and internal space utilization efficiency. These smoke launchers featured Multi Spectral Aerosol grenades.
The Commander’s Optics were changed as well. It was an entirely new development from Saab, the Panoramic Low Signature Sight (PLSS) that had the unique feature of not changing its silhouette while being operated due to its spherical profile. The PLSS offered complex optics and extended the capabilities of the vehicle commander by giving him a hunter-killer option, effectively allowing him to slave the gun to his optics. The CV90120-T could also use later variations of the Lemur Remote Weapon Station instead of the PLSS, provided by Saab.
Later variants of the CV90120-T also received the newest BAE Rubber tracks to lower the overall weight of the vehicle.
Active Protection System
A new active protection system was also unveiled for implementation to the CV90120-T, the “AAC” Active Armor Concept. Developed by Åkers Styckebruk, it functions by firing a sensor-activated and directed high explosive charge towards projectiles to disrupt large-caliber ammunition impacts on the vehicle, acting as a last resort defense if all preceding systems have failed to protect the vehicle.
The CV90120-T has yet to be procured by any nation in the world, but it did face testing and trials in Poland in 2007, as the Polish Army was seeking to expand its military combat capacity. This led to the reveal of the PL-01 concept vehicle in 2013, based upon what they learned when trialing the CV90120-T.
CV90120 Ghost
The CV90120 is still being developed to this day. In 2011, BAE Systems appeared at the Defence and Security Equipment International (DSEI) exposition with the newly built CV90120 Ghost. This vehicle had a revolutionary new thermal cloak system called ‘ADAPTIVE’, an active thermal camouflage. It features a hexagonal system mounted to the sides of the chassis, that can modulate and control its own temperature via electronic programming to mask the chassis entirely, or to make different distinct shapes like cars or other environmental factors that would not be considered an enemy.
The vehicle also features some other new stealth-based changes based on protecting the vehicle against radar-detection as well, focusing harder on remaining undetected.
Firepower
Due to RUAG ceasing all marketing and production of the previous CTG L/50 120 mm gun, a new gun was necessary. The choice came to an entirely new gun developed by the German company Rheinmetall. This was the Rh 120 LLR/47 (LLR – Light, Low Recoil) smoothbore cannon. This gun can be traced back to 2003 as a private development venture from Rheinmetall Weapons and Munitions, desiring a gun that could provide equivalent firepower to the current M1A2 and Leopard 2 tanks but with a lower weight. Its design can be considered a successful venture by performance, giving up to 44% less recoil as it fires.
The gun’s fume extractor and thermal shield have also had their shape modified to decrease the vehicle’s signature, allowing improved stealth.
The success of this lightweight 120 mm gun with equivalent performance to normal MBT guns is also attributed to the steel type used, which was developed to be used with the older Future Tank Main Armament (FTMA) program that aimed to design a 140 mm smoothbore gun for military usage.
As of the writing of this article, in June 2020, no countries are looking into trialing or buying the CV90120.
Summary and the future
Light tanks have always been a debatable topic, as most nations now deem them unnecessary. Hägglunds has attempted to prove that the concept is still viable, and it is possible to hit enemies with speed, firepower and elude retaliation with the appropriate ‘soft’ protection levels, but light physical armor. Adding more armor does not necessarily guarantee safety to a vehicle, whereas not being seen in the beginning might arguably be the ideal choice in a large number of battlefield situations.
The huge investments into the entire CV90120 line of development seems cemented into BAE Hägglunds dedication to making one of the most advanced light tanks of all-time, whereas other nations either struggle to make one, simply do not see the point in one, or can not find a balance when developing one.
Nevertheless, the CV90120 is still without any customers and is still being developed. With military doctrine and battlefield tactics evolving every year that passes, there might be a place for the future developments of the CV90120 on the battlefields of the future. BAE Systems will likely be ready for the day that happens.
CV90120 Specifications |
|
| Size | Length: 8.3m (incl. gun) 6.6m (hull) Width: 3.3m Height: 2.8m (panoramic sight) 2.4 (turret roof) |
| Crew | 4 |
| Combat Weight | Prototype – 21 Tons Current Model – 35-40 Tons |
| Engine | Scania DS 14 or 16 550-1200 hp V8 Diesel |
| Max Speed | 70 km/h forward, 40 km/h reverse |
| Transmission | Allison X-300-5 Automatic Gearbox |
| Armament | RUAG CTG 120 L/50 or Rheinmetall LLR L/47 |
| Ammunition | Modern NATO compatible, 120mm |
Sources
baesystems.com
ruag.com
RUAG Aerospace Defence Technology
Rheinmetall Defense
Swedish Armour Historical Society CV90 Photo Guide 2010
Tankograd CV90 International 8003 2010
IHS Jane’s Land Warfare Platforms: System Upgrades 2014-2015
