The Development And Use Of Wheeled Armoured Fighting Vehicles

INTRODUCTION

The use of wheeled armoured vehicles in combat has fluctuated according to the nature and tempo of the operations in which armed forces are engaged.  However, the rapid growth of low and medium-intensity operations in recent years has placed greater emphasis on mobility and armour than on firepower.  This has led to a debate on how far the transition from mechanised forces relying mainly on tracked vehicles to forces in which the majority of vehicles are wheeled can progress, without loss of combat capability. 

Two questions currently being addressed are:

1.  Can wheeled armoured fighting vehicles be used to meet all the operational requirements of the contemporary world?

2.  Can  wheeled armoured fighting vehicles be sufficiently well-armed and armoured to be sent into combat without losing any of their essential off-road capability?

The experience gained from the operations in which armed forces are currently engaged indicates that compact, mobile, well-protected vehicles are essential to success - especially given the increasing counter-insurgency nature of the majority of modern operations. 

One other lesson being learned (or, more accurately, being re-learned) is the economic cost of such operations.  The military can no longer rely on the relatively high budgets of the Cold War era and, although the political will to provide properly equipped forces for peace-keeping, counter-terrorism and counter-insurgency operation remains the same, there is an increasing demand for more cost-efficient operations and equipment. 

This translates into smaller, more responsive forces, probably equipped with a family of wheeled armoured fighting vehicles, instead of a fleet of relatively large, heavy, tracked vehicles.

BACKGROUND

Wheeled armoured cars were first used for reconnaissance tasks and general harassment of the enemy during the opening stages of the First World War.  However, once the European battlefields had entered the static, trench warfare, phase the opportunities for such operation were limited, because there were few useable roads remaining.  Later, of course, the effort to develop a fighting vehicle with an off-road capability led to the development of a completely new type of weapon - the tank.

Although armoured cars could achieve little on the static battlefields in France, they continued to be used to effect elsewhere.  Russia showed an early interest in wheeled fighting vehicles and began serious development of armoured cars immediately after the Russo-Japanese War of 1904-05.  In fact, Russian advances in the design of wheeled armoured vehicles continued to affect Soviet military doctrine even after the Second World War.  When western armies began fitting tracks to their armoured vehicles the Warsaw Pact continued to use wheeled vehicles to carry at least half of its infantry on the battlefield.

At the start of the Second World War the west had little interest in wheeled armoured cars and only the German and French Armies attached much importance to them.  This was to change quickly after the shock successes won by the mobile operations of the German armoured forces, which included armoured cars as the basic reconnaissance vehicle of the panzer divisions.

Most armies with combat experience from the Second World War noted the astonishing successes of the ‘Blitzkrieg’ tactics employed by German mechanised forces and deduced that the outcome of future ground combat would be decided by medium to heavy tanks  accompanied by tracked platforms for the infantry and artillery. Wheeled armoured vehicles, if used at all, would carry out light reconnaissance and internal security over rear areas and captured territory.  There was one notable exception to this view, however, and that was the Red Army.

In the 1950s the Soviet Army carried most of its infantry in wheeled armoured personnel carriers and this trend continued throughout the 1960‘s, despite the introduction of tracked infantry fighting vehicles.  The reason for its continued employment of wheeled vehicles in such numbers was directly related to the Warsaw Pact’s belief in manoeuvre warfare and the aim of Soviet military planners at that time, which was to advance as rapidly as possible into France within a few days of the outbreak of war.  Speed was of the essence, so wheeled vehicles were selected, because the Soviet Army considered wheeled armoured transport to be faster and more reliable than tracked vehicles for moving large masses of soldiers over long distances. 

Wheeled armoured fighting vehicles offer advantages over tracked fighting vehicles in certain roles as they are more suited to long-distance and rapid deployment than tracked.  There are two main reasons for this:

1.  Wheeled vehicles need fewer refuelling stops, because the average road range of wheeled vehicles exceeds that of tracked vehicles by between 50% and 100%.

 2. The average marching speed of wheeled vehicles on roads is between 50% and 100% higher than that of tracked vehicles.

Since the end of the East-West confrontation, however, there has been a drive to develop expeditionary-style forces to deal with the rapid emergence of regional crises and conflicts.  In dealing with these crises, which are increasingly typified by their counter-insurgency nature, light ground forces - and especially wheeled armoured vehicles - have taken a prominent role. 

THE ROLES OF WHEELED ARMOURED VEHICLES - DESIGN REQUIREMENTS

PROTECTION

Typical tasks offering considerable scope for the employment of wheeled armoured vehicles include: patrolling, counter-insurgency operations, internal security, peace-keeping and peace-enforcement operations.  Underlying this is the assumption that relatively light wheeled vehicles are more appropriate than the traditional ‘heavy mix’ of tanks and tracked infantry vehicles for patrolling and controlling an area under threat from insurgents, guerilla forces or terrorist occupation.  The use of lighter, wheeled vehicles is considered better-suited to the mobile military presence essential to establishing and maintaining order and the rule of law, without causing undue alarm to the civilian population.

However, the increasing use of improvised explosive devices (IEDs) and rocket propelled grenades (RPGs) as the insurgents’ weapons of choice has led to alterations in the basic design of wheeled vehicles, so that they provide much higher levels of protection.  Without this, such vehicles would be at a serious disadvantage and their operational effectiveness would be reduced.

Levels of protection and survivability can be enhanced in a number of different ways and all of them need to be considered, if the usual design compromise between Mobility, Protection and Firepower is not to be completely overwhelmed by an operational requirement to increase IED and RPG protection above all else.  Mobility can increase survivability by providing the capacity to overwhelm an opponent by the rapid assembly of a superior force. 

Evasive manoeuvring and the ability to avoid likely ambush sites by travelling cross-country and using ground to advantage can also indirectly contribute to survivability.  Such relatively simple tactics make it harder for the enemy to gain a position of advantage, but any discussion of survivability - particularly when the main threats are from IEDs and RPGs - always comes back to increased armour and that generally means extra weight.

Unfortunately, the levels of protection achieved by main battle tanks are simply not available to wheeled vehicles, because of the effect the weight of armour needed would have on the vehicle’s mobility.   Such a limitation means that it is unrealistic to expect wheeled armoured personnel carriers - even those of 20 to 25 tonnes in weight - to provide protection against anything more powerful than a heavy machine gun (i.e. 12.7 mm to 14.5 mm).  Even then, only the frontal arc is likely to be protected against weapons of any calibre larger than 12.7 mm.

There is still no effective way to defeat high-velocity armour-piercing long rod penetrators fired from a high pressure tank gun other than by weight of armour.  Nor is there anything that current protective systems other than armour can do to defeat machine cannon, whose calibre and rate of fire have been increasing.  However, such weapons are generally confined to national armed forces, while the weapons most often used against counter-insurgency forces are the IED, RPG and the AK47. 

While an effective weight of armour is of real value against such these, there are other ways of increasing protection based on improved sensors, on mobility, on high levels of training, on intelligence gathering and the timely dissemination of early warnings.  Wheeled armoured vehicles are not necessarily at any greater disadvantage than tracked in such circumstances and they can be expected to perform as well.  

MOBILITY

Most of the wheeled armoured vehicles in service today - roughly 90% of them - weigh less than 20 tonnes.  This compares to an almost even split in the case of tracked vehicles, where roughly 50% weigh 35 tonnes or less and the other 50% weighs between 35 and 65 tonnes.  It is clear, therefore, that are some areas where it is possible to employ either wheeled or tracked vehicles.  Within the limits of current technology, however, tracked vehicles are essential at the heavier end of the scale, because the wheeled version cannot yet fully meet that particular requirement.

That said, where tracked vehicles have been chosen in preference to a wheeled variant the principal reason has generally been the inherently superior performance of the tracked vehicle over the more difficult types of terrain, such as wet clay soils. 

However, these soils represent only a small part of the spectrum of operational conditions met by armed forces and in almost all other conditions the off-road performance of a well designed wheeled vehicle will usually prove to be at least adequate to cover the terrain.  Once this is recognised then a well-designed, compact, wheeled vehicle is likely to become a more attractive option than the equivalent light tracked vehicle.

FIREPOWER

In the past the need to reduce the weight of wheeled fighting vehicles generally meant fitting a small weapon of limited value.  That is no longer the case.  Although wheeled vehicles do not often mount the sort of high pressure gun carried by a main battle tank, they can certainly deploy an anti-tank capability in the form of anti-tank guided weapons carrying a HEAT warhead.  In addition, some wheeled armoured vehicles in the 25 to 30 tonne class are equipped with 105 mm guns and this can provide significant fire-power to an expeditionary force. 

Most armoured personnel carriers are armed with a machine gun for local defence and to provide limited fire support.  Some vehicles are fitted with turret-mounted cannon for added firepower, although the weight of the ammunition and the volume it occupies are important factors in the design of the vehicle and the role it is to play on the battlefield.  Armoured personnel carriers equipped with cannon are often designated as Infantry Fighting Vehicles (IFV) and this is a significant change, since IFV’s can fight by themselves as well as transport infantry. 

Although the IFV is not designed to be a light tank, it offers considerably more direct fire support than a simple machine gun and this is made increasing use of in counter-insurgency and counter-terrorist operations, where the enemy is unlikely to be able to field a tank threat. 

As always, however, there must be a design compromise and the weight of a weapon and its ammunition is a not inconsiderable factor in designing the mobility capability of any infantry vehicle.  So, if indirect fire weapons, either artillery pieces or mortars, are to be carried on a wheeled chassis, then there are sound economic and operational reasons for producing a family of vehicles with variants optimised for specialist roles.

A lot of work has been done in recent years trying to develop an effective electromagnetic gun.  However, the space needed to generate and store the energy to power the weapon is estimated at being in excess of 5 cubic meters. So, at the moment, it is unlikely that such a system will be light enough to be mounted on a wheeled fighting vehicle.  As usual, therefore, the  most sensible course is to make best use of the advantages offered by wheeled vehicles in reconnaissance, security and counter-insurgency roles and not try to effect a compromise in their capabilities.

THE FUTURE ROLES OF WHEELED ARMOURED FIGHTING VEHICLES

The increasing use currently being made of wheeled armoured vehicles in the proliferation of low and medium intensity operations against skilled and determined enemies should be sufficient demonstration that it is not essential to fit tracks to combat vehicles.  It is more important that vehicles and forces are correctly structured and in sufficient strength to complete the task.  This means that wheeled vehicles are more than adequate for use in conflict - unless there is a requirement to join combat against modern main battle tanks. 

The roles which wheeled armoured vehicles can perform are based on the operations of the parent formation.  Current thinking is in the development of ‘broad spectrum’ intervention or expeditionary forces trained for traditional war fighting, as well as peace-enforcement, counter-insurgency operations and humanitarian missions on behalf of the UN and regional organisations.  Typically, such a force could be required to carry out a mix of a wide range of key military activities, so it is probably necessary to consider a force structure based around three families of vehicle -

 1.  A heavy family, well protected and able to engage the enemy with direct fire.  These vehicles will comprise the main battle tanks needed to deal with enemy armour and a mechanised infantry combat vehicle with high levels of protection.  They will weigh typically around 50 tonnes or more and, consequently, are almost certain to be tracked.

  2. A medium family of variants based on a common 8 x 8 wheeled platform and weighing around 25 - 35 tonnes.  These vehicles could include tube artillery, a multiple-launch rocket system, and/or a fibre-optically guided missile array.  The main role of this section of the force will be to provide fire support, which requires a high level of operational mobility.

  3.  The light family, based on 4 x 4 or 6 x 6 chassis, will be by far the largest.  There will need to be specialist variants for reconnaissance, a personnel carrier, possibly an anti-tank missile system, mortar vehicle and air defence. All vehicles in this class should be very compact and relatively light, although the design will allow significant extra weight to be added once the vehicles are in-theatre.  Compactness and agility will enhance their survivability, but the extra power-in-hand included in the design will allow armour modules to be added to face a specific threat.  

There is, therefore, a good argument for adopting a heavy, medium and light vehicle mix based on a family of wheeled, armoured fighting vehicles, since these can meet almost all the requirements of a major expeditionary force while, at the same time, reducing the cost of ownership. 

The only exception to this would be the ‘Heavy’ family, since the present trend of technological development offers little hope of seeing a medium-weight wheeled vehicle with sufficient protection to confidently undertake the most demanding and dangerous of combat missions - a direct confrontation with a main battle tank - within the next 15 years or so.

THE COST

Wheeled armoured vehicles used to be cheaper than their tracked counterparts.  They were simpler and more use could be made of ‘commercial-off-the-shelf’ components - relatively inexpensive parts or sub-systems, such as engines and tyres, from large-series civilian production.  Unfortunately, the cost differential is no longer so marked.  Wheeled armoured vehicles, especially the large, multi-wheeled ones, have become increasingly more sophisticated.  As a result, the lower procurement costs of wheeled vehicles in earlier years has, with a few exceptions, disappeared.

Wheeled vehicles do still retain one other cost advantage, however, which is that they tend to be less expensive to own and operate.  They can travel farther than tracked vehicles for the same quantity of fuel and their maintenance requirements are easier than with tracked vehicles.  What is more, using vehicles with a basic family design reduces the size and cost of the spares holding, reduces the cost of driver and crew training and allows maintenance to be planned at fleet level.  This all helps to provide an outstanding deal for the Users and the Owners of those vehicles.