Modern soldiers face different ballistic threats depending on their role and mission. Not every soldier needs the same level of protection. It depends on their job, the terrain, and the specific risks involved. That’s why armies are moving towards scalable ballistic protection—kits that can be adjusted by adding or removing armour elements to suit the situation.
Scalability is often paired with modularity, meaning the protection system consists of interchangeable armour panels. In practical terms, this allows troops to customise their gear, increasing or decreasing protection based on mission demands.
Several nations have already adopted this approach. Examples include the British Virtus system, manufactured by Israeli firm Source Tactical, the US Soldier Protection System (SPS), Germany’s MOBAST by Mehler Protection, and Finland’s RESTAC by Sioen Ballistics. Nordic Defence Review takes a closer look at Virtus, as the author has nearly a complete set.
Vital Protection
At the core of any ballistic protection system is the vest—designed to protect critical circulatory organs like the heart and aorta. Helmets and eye protection are also essential. This is the bare minimum a soldier needs. Additional soft and hard armour panels can then be added depending on the mission.
A soldier can be hit from multiple angles—not just front or back. Penetration routes into vital areas vary, and while it’s impossible to block them all, key vulnerabilities—such as the shoulders and upper arms—must be addressed.
“Projectiles hitting from the upper torso—shoulders and upper arm areas—are a major cause of lethal injuries,” said a Finnish volunteer fighter with frontline experience in Ukraine, speaking to Nordic Defence Review. First-hand accounts like these are invaluable for developing better protective systems.
Light vs Heavy Armour
Our Finnish contact also noted a preference for lighter gear, prioritising mobility over protection. In Ukraine, soldiers take different approaches—some opt for more armour (tactical vests), others for less (plate carriers). The trade-off between mobility and protection needs careful analysis.
“The balance has shifted over time,” said Finnish manufacturer C.P.E. Productions Oy. “There have been periods where heavier protection was the norm, before trends moved towards lighter, more agile systems.”
In Afghanistan and Iraq, US and British troops initially used bulky, full-coverage armour. Later, they transitioned to lighter setups for improved manoeuvrability.
The ideal level of protection depends on multiple factors:
- Threat type – What weapons are being used?
- Climate – Heavy armour in extreme heat can be fatal.
- Role – Light infantry may need more mobility; mechanised troops can carry heavier loads.
- Terrain – Urban warfare and open fields require different protection strategies.
Scalable systems offer flexibility, ensuring soldiers get the protection they need without unnecessary burden.
The Real Killer: Fragmentation
On modern battlefields, bullets aren’t the main killer—fragments are.
“In Ukraine, around 70% of casualties come from fragmentation,” our Finnish source said. This suggests soldiers would benefit more from full-coverage fragmentation vests rather than standard plate carriers with hard armour inserts.
That said, most troops feel vulnerable without rifle-rated plates. The psychological reassurance of knowing your kit can stop a direct rifle shot is significant. But overconfidence can be dangerous.
The nature of combat influences casualty types. In Afghanistan, bullets played a greater role because insurgents lacked the artillery and shelling power seen in Ukraine. The most common threats there were firearms, RPGs, and IEDs. And IEDs weren’t just simple explosives—many were enhanced with fragmentation elements like nails or ball bearings.
Fragment Simulating Projectiles (FSPs) used for testing ballistic resistance. They have a chisel shaped nose to simulate an average real-life fragment. Fragment shape depends on the fragmentation method: natural, controlled, and preformed. (Image: Armament Research Services – ARES)
The British Virtus System
The Virtus system is the UK’s current soldier protection package.
“It’s an integrated combat and protective system designed for modern infantry,” said the British MoD.
Manufactured by Source Tactical, Virtus benefits from being a single-source system, ensuring compatibility between components. Mixing and matching gear from different suppliers can create problems with fit and function. Introduced in 2016, Virtus has been in service for nearly a decade. The British Army is modernising its equipment, but it remains unclear when Virtus will be replaced. Notably, the system had to be upgraded just two years after its introduction.
Scalability and Protection Levels
Virtus offers four primary ballistic protection levels, with nine variations in total. It can be worn as a lightweight plate carrier or as a full-coverage tactical vest.
Level one protection is a concealed carry option. Level four is the heaviest option with all modular soft armour elements fitted, including four hard armour plates or inserts. Level four is a very heavy configuration. It should – and more likely can – be worn only for a short duration of time.
The heaviest configuration is impractical for prolonged use, as it leads to rapid exhaustion. However, tests in controlled environments, such as indoor ranges, show it can be worn comfortably for short periods.
The Virtus Scalable Tactical Vests (STV) come in nine different sizes—far better than a “one size fits all” approach. Proper fit is critical for comfort and effectiveness. If unsure between two sizes, it’s best to opt for the smaller.
The system’s soft armour panels, made from aramid fibres, are primarily designed for fragmentation protection. Weighing around 4kg/m², they also offer NIJ Level IIIA resistance but fall short of full trauma protection standards due to their lightweight design.
Initially, Virtus used legacy hard plates from the Osprey and Enhanced Combat Body Armour (ECBA) systems—Osprey plates for front and back, ECBA plates for the sides.
A Well-Designed System, But Not Perfect
Overall, Virtus is a well-thought-out system. It offers excellent scalability, and its components integrate seamlessly. The range of sizes ensures a better fit across different body types.
However, one notable flaw is the lack of lower abdominal protection. Blast waves can cause severe internal injuries, particularly if gas-filled organs like the intestines are exposed.
Soft armour isn’t effective against blast waves. A better solution would be rigid plates made from composite materials, which disrupt stress waves by creating impedance mismatches. This reduces the energy transferred to the body, such as the acoustic impedance – speed of sound of the material multiplied by its density – mismatch between different materials. This causes stress wave reflections between material boundaries and less energy exerted on your body.
The Future of Ballistic Protection
Scalability and modularity will continue to shape body armour development. Militaries are demanding lighter, more adaptable systems, but new threats are constantly emerging. The arms race between protection and penetration never stops.
While modern ballistic armour is getting lighter, advances in ammunition technology are driving the need for even tougher materials. New calibres, such as the US Army’s 6.8×51mm, deliver greater energy and penetration than 7.62×51mm NATO, posing fresh challenges for armour designers. The 6.8x51mm has a lower drag and more elongated bullet. The longer armour piercing core delivers more penetration and a longer effective range.
It remains to be seen how the next British soldier system will evolve, or what direction the US Soldier Protection System will take. But one thing is clear—scalable ballistic protection is here to stay.
Read More:
- Source Tactical Gear: Virtus Soldier System
- The British Army
- Sioen RESTAC
- Soldier Protection System
- Mehler Systems MOBAST
