Future-proof vehicles - upgrading armoured vehicle capabilities

Armoured vehicles have life cycles of 20-30 years or more. During that time, they must be easily configured for a variety of roles, and able to adapt rapidly to many diverse threats and environments. To maximise operational effectiveness, they must also be upgraded as technology improves.

Balancing act

"When you look worldwide, there's a whole range of vehicle upgrade programmes," says Ben Barry, senior fellow for land warfare at the International Institute for Strategic Studies. "Some might replace the engine and gearbox, others strip out all the communications and replace them with digital ones. Others modify the hull and turret."

Just as different consumer car models share the same floor plan and subsystem, most armoured vehicle programmes will base their different variants on a single platform. This maximises component commonality across hull, powertrain, weapons, electronics and other systems, and offers the best value in manufacture. It also makes field logistical support and maintenance easier and more cost-effective.

But designers also have to build in 'stretch potential', leaving room for upgrades, with vehicle weight being the most pressing concern. Although they might strive to keep mass as low as possible in the original model, designers must ensure the shared platform can cope with extra load in the future.

"If you are going to try to design an armoured fighting vehicle (AFV) with flexibility and stretch potential from the outset, you need to think about what that future weight will be," says Barry. "So if it will be stretched later in its life to 40t, you might design it initially at 35t."

As shown by the jumps in weight experienced by the US and British AFVs used in Iraq and Afghanistan, any increase is most likely to come from extra armour. Warrior is a prime example. Extra armour, at a cost of £570,000 a vehicle, was added to Warrior's undercarriage and sides, along with more robust seating to cope with insurgent RPG and IED attacks. That took it from around 25t to 40t and, among other changes, the vehicle required an uprated gearbox to cope.

"Until people come up with revolutionary armour or some other breakthrough in defensive aids, the heavier the vehicle, the better protected it's going to be," says Barry, who also notes that making the design light in the first place is often not the best method. "If it's got a heavy gun on it, a lightweight vehicle will experience greater recoil, making it less accurate."

The UK's Ajax (previously Scout SV) platform has that extra capacity designed in. Its baseline weight is 34t, but appliqu???? armour (modular and upgradeable) takes it to around 38t, while its upper weight limit of 42t still offers room for future expansion.

"Ajax has been designed with all the hard lessons learned in Iraq and Afghanistan in mind," says Barry. "Its ability to upgrade is the key to success."

Generic Vehicle Architecture

Vehicle electronics systems are certain to need numerous future upgrades as equipment improves and digital aids continue to proliferate; and aiming for compatibility in interfaces, components and component architectures is the best way to enable this. Barry notes that this is already a long-standing army practice.

"Radios are a good example," he says. "The army always tries to fit the same standard radios across their vehicles to reduce logistical challenges and costs, and so on."

The Generic Vehicle Architecture (GVA, or Def Stan 23-09) standard is a continuation of this approach - the successor of many other vehicle electronics programmes going back decades, such as SAVE, VERDI, VESTA and VSI. The Platform Integrated Command and Controls System (PICCS) and Common Infrastructure for Battlefield Information Systems (CIBIS) were attempts to standardise crew workstations, and power, sensor and other electronic systems integration, and were effectively building blocks for GVA.

First published in 2010, GVA supports Gigabit Ethernet among other networking standards, and aims for the widest possible subsystem compatibility. This eases upgrading and the connection of legacy systems via adaptors.

A key enabler is GVA's incorporation of the Data Distribution Service middleware system that allows otherwise incompatible systems to talk to each other. NATO has also adopted GVA as the basis for its wider STANAG 4754 standard, a draft of which will be released this year.

Common guns

This ever-increasing payload of electronics and other electrical systems in vehicles has knock-on effects elsewhere. Electrical generators and auxiliary power supplies must have spare capacity to drive extra electronic countermeasures, communications systems and cooling equipment. Raising vehicle supply voltage far beyond the conventional 24/28V is one of the design changes made to cope with elements like this.

"Armoured vehicles are being designed from the outset to have more electronics in them," says Barry. "This drives up the requirement for internal volume and power supply, and, again, adds weight."

Ajax's turret is a good example of designing for growing room, freeing up space for new systems with a large 1.7m turret ring and further space created by placing the main ammunition feed under armour outside the turret crew compartment. The revamped Warrior will share turret subsystems with Ajax, along with its CTAI-developed 40mm cannon - another key area for standardisation.

"The use of common guns means you can share ammunition, components and training," says Barry, pointing to the UK's Centurion as an early example of gun standardisation. "When the UK upgraded the Centurion's gun to 105mm, that gun was then used by all the people that bought Centurions, and extensively on the Leopard and other tanks."

If a gun is widely adopted, upgrade paths are likely to become cheaper and easier to take. For example, the Leopard 2's Rheinmetall 120mm gun is also used on the M1 Abrams. With the current L/55 model's ammunition also backward compatible with the previous L/44 version, the numerous nations deploying these two tanks can easily access a wide range of compatible, lower-cost ammunition and spare parts.

"Germany and the US now use that common 120mm gun," says Barry. "That, to my mind, is the single biggest problem and risk with the current Challenger upgrade. The only other militaries that use the British 120mm rifled gun are Jordan and Oman, meaning they won't get economies of scale or the other advantages of commonality that come with the M1 Abrams or the Leopard 2."

Barry cites Warrior as one leading UK example of a flexible platform. Although the original design reached the limits of its stretch potential, the decision to rebuild on top of the basic Warrior platform indicates that GKN Defence got the basics right over 30 years ago.

"It was a good armoured vehicle that adapted well to being used in ways that were completely unforeseen," says Barry. "The original design was simple and offered sufficient space for expansion, so it coped quite well with 10t of extra armour and other upgrades. To achieve that, it had to be a good armoured vehicle in the first place."

The £1-billion Warrior Capability Sustainment Programme that will rebuild the vehicle from the ground up is now well advanced. "Warrior is probably the most extreme upgrade programme in the world at the moment," says Barry. "It will retain its hull and, probably, its running gear (tracks and sprockets), but everything else is going to be new - from the seating to the electronics."

Plan for the future

As the best international example of modern AFV design, Barry singles out Russia's Armata Universal Tracked Platform. The platform is the basis of the T-14 and T-15 tanks, a combat engineering vehicle, an armoured recovery vehicle, the Kurganets-25 heavy armoured personnel carrier, and a tank support combat vehicle.

The BTR-90 Boomerang 8×8 wheeled armoured personnel carrier was developed alongside the tracked vehicles, and will be able to mount the same 30mm Epoch remote control turret as the T-15 and the Kurganets-25. All of the vehicles bristle with new features, which include active protection systems that defend against antitank munitions, and base - rather than appliqué - explosive-reactive armour. In what could be an outstanding example of upgrade planning, the T-14's digital control system has also apparently been built to accommodate robotic crew-free control in the future.

"All three main vehicles have been designed from the outset as a common family," says Barry. "The T-14 Armata is a great tank, and is interesting because the turret is quite large for the size of its gun. It's very possible that the turret has been designed to accept a bigger 152mm gun in the future."

Any sizeable AFV programme will always be a mass of compromises. Most obviously, the desire to build vehicles quickly and cheaply clashes with the need for broad capabilities and service-wide standardisation. Long, evolving consultations within the UK services and with allied nations further lengthen the complex multistage design and procurement processes, in which needs and specifications will inevitably change over time.

"There's no silver bullet for standardisation and compatibility," concludes Barry. "But a good combat-proven design like the Leopard 2 or the CV90 will always sell itself."

The good news is that the UK defence sector has learned from previous troubled projects like FRES and the hard lessons of active service deployments. With that experience, future armoured vehicles have a better chance of performing optimally and cost-effectively for decades to come.