<XMP><BODY></xmp>Tanks: Endangered, Extinct or Due to Evolve?

Added 18-2-19
Updated 24-4-24

Tanks: Endangered, Extinct or Due to Evolve?

This article should be read in conjunction with that on APCs.

Over my many decades of writing the Scrapboard, I have often come across statements such as “tanks are obsolete” or “ATGW/precision-guided weapons/RPGs have made tanks obsolete”.

In 1981, I read an article in Scientific American on precision-guided weapons. The author predicted (p45):

“As small missiles become more accurate and deadlier, the major capital pieces of equipment- the tank, the combat-support aircraft and the large surface ship-will ultimately become obsolete for virtually all war-fighting tasks. They will then be relegated to a largely ceremonial role, being put on display in Russian May Day and American Memorial Day celebrations.”

This paints an intriguing image, but nearly forty years later the tank is still with us.

Statements such as the above are based on a common misconception.

The misconception is that if a tank is not totally invulnerable, it is no longer useful.

Throughout its history, the tank has usually shared the battlefield with weapons that can kill it. Even in HG Wells’ story “The Land Ironclads” the armoured vehicles were destroyed by field guns.

Incidents where the tank has been immune to most of the weapons it faced have been relatively rare.

A system does not usually become obsolete until it can no longer do the task that is required of it, or until a better alternative becomes available.

Occasionally, a system becomes obsolete because a counter system makes its operation impractical.

Horses were used in warfare for thousands of years, despite their vulnerability to arrows, spears, bullets and many other threats.

It was the motor engine and aeroplane, rather than the machine gun and rapid-fire rifle, that caused the decline of the horse in military use.

In fact, military use of horses lasted until at least 1945. Several divisions of horse-mounted cavalry operated on the Eastern Front, and even greater numbers of horses served to move supplies.

The Need for Armoured Transport

Often the “tanks are finished” scenario paints a picture of a swarm of infantrymen armed with tank-killing missiles.

A dismounted fighter can move through terrain that a vehicle cannot and hide in places where he is least expected.

Vehicles are noisy, so a fighter on foot often has ample time in which to hide from an approaching threat.

Modern shoulder-launched munitions (SLM) give an individual infantryman tremendous destructive potential. A competent fighter can pop-up from behind cover, fire and disappear in a fraction of the time a similar attack by an armoured vehicle would take.

This scenario usually fails to address how the infantry move themselves and their missiles around?

A dismounted man usually carries only two or three RPG rounds. Many of the more potent weapons are even heavier.

Helicopters can move infantry, but are highly vulnerable if any air-defences are present.

Where the terrain allows, the infantry are likely to use some form of ground vehicle to move themselves, their missiles and other necessities.

Vehicles that can serve as mobile arms caches in fact constitute an important element of these tactics.

Piling troops into trucks or pickups is not practical if there is any chance of an enemy firing at them. A ground vehicle is of limited practical value if anyone with a rifle or petrol bomb can disable it.

If modern weapons have made armoured vehicles vulnerable, then moving in trucks and jeeps is suicidal!

The recent misuse of HMMWVs as combat vehicles has once again re-taught this lesson at a bloody price!

Clearly we need to adapt our tactics and technology to the Bazooka Age.

Can Tanks Be Replaced?

An important consideration is does the role the tank serves disappear if the tank really is obsolete?

If the answer is “no”, this poses the question: “What will replace the tank’s role?”

Many “tanks are obsolete” articles offer up plainly inferior alternatives. The US Army’s Stryker MGS is an example of this. Like a tank, it is a large target, yet it has inferior protection and inferior cross-country mobility.

Some parties will offer up airpower as the solution.

Sophisticated as modern aircraft are, they are still subject to the vagaries of the weather. There will be times when aircraft just cannot fly.

Even relatively “low-tech” aircraft are expensive and delicate.

Even if low-cost UCAVs also contribute to air-support, a commander will seldom ever have the levels of air support he desires.

Low-flying aircraft are vulnerable to automatic weapons, which are likely to be common on a modern battlefield.

Higher-flying aircraft will have to contend with guided-weapons and possibly, in the near future, directed-energy weapons (DEW).

Airpower cannot meet all of the fire-support needs of ground troops.

Artillery is another partial answer.

For several decades now, new technologies have made precision indirect-fire possible.

Some armies are already using long-range anti-tank missiles as over-the-horizon (OTH) weapon systems alongside more traditional artillery weapons.

Vertical launch system (VLS) configurations may reduce the need for sophisticated launch vehicles. Missiles might be fired directly from their shipping pallet, making any transport vehicle a launcher. Alternately, pallets can be placed at strategic locations and fired remotely to support local forces.

Useful though these capabilities are, they are of limited use in close terrain or if friendlies or civilians are close to the target.

Both artillery and airstrikes require good channels of communication, an assumption that cannot be made in combat. In the near future it is likely that even irregular forces will utilize electronic warfare.

Where artillery and airstrikes cannot be used, close-range direct-fire will be needed.

The quantity of munitions a dismounted infantryman can carry is limited, so he will need support from vehicle-mounted weapons.

Understanding Battlefield Bullies

Over a century of use confirms that tanks work best in company. Infantry are needed to scout and screen them. Artillery help disrupt defences and screen movement. Air defences deter attack from above and provide additional firepower.

My friend Ralph Zumbro was fond of describing tanks as “Battlefield Bullies”. The insight behind this label is easy to overlook.

Like most bullies, tanks are most effective when they enjoy most of the advantages.

Where terrain and/or armament may give an enemy a significant anti-tank capability, tanks and other fighting vehicles are best held back. The tanks should be applied to points where infantry, artillery and/or air attacks have successfully diminished enemy anti-tank capability.

Neglecting this simple principle has needlessly wasted many tanks and combat vehicles.

The Big Gun Question

Does the future direct-fire-support vehicle need a large-calibre tank gun, and its associated penalties in weight and bulk?

While the Rooikat armoured car can mount a 105mm weapon for export sales, South Africa decided a 76mm gun was a more practical choice.

Automatic cannon and machine guns can deal with most battlefield targets. (The author favours the 35/50mm Supershot).

Targets that cannot be neutralized by autocannon can be dealt with by missile, either the vehicle’s own, or those of allied aircraft and artillery directed by the vehicle.

Infantry fighting vehicles have served in a “tank” role in some recent conflicts. The Danes have made good use of their 35mm-armed CV90s in Afghanistan.

If we follow the above logic and replace the infantry cargo of an IFV with more VLS missiles, we have the Thunderback tank concept I have described elsewhere.

Other than its role, the main difference between a future tank and an IFV may be its increased missile allocation and possibly more extensive targeting systems.

I do not believe the tank is about to disappear any time soon, but it may evolve and change form.

Airpower, artillery and direct-fire are of little use unless the target can be located.

The military ground vehicle may have an important role in this respect too.

A vehicle can mount a wider and more powerful range of sensors than a dismounted squad can field.

The sensors of a future tank or fire-support vehicle may become as important as its organic weapons.

Many armies field separate “armoured” and “armoured reconnaissance” units, both often of cavalry ancestry. It may be time to remerge those bloodlines and recognize a unit’s tanks can be eyes as well as fists: hunters and killers.

As John J. McGrath notes in his book “Scouts Out!”:

“In all recent US Army conventional operations, the most common type of action was movement to contact, a type of operation in which the lead unit, whether cavalry or not, was effectively the reconnaissance element. Similarly in nonconventional operations such as counterinsurgency, where there are no actual front lines, all combat (and even most combat support and some combat service support units) units become de facto reconnaissance units by the nature of the conflict...Instead of being a function of specialized troops, perhaps reconnaissance is one of many functions of maneuver units similar to attack, defend, or move. Commanders cannot misuse units if they are organized and equipped to perform a variety of functions, of which reconnaissance is but one.”

Any mechanized/armoured force needs a mixture of direct-fire, indirect-fire and dismountable elements. Logic suggests some of these capabilities be organic to a unit.

Strategic and Operational Mobility

The main battle tank (MBT) remains the “queen of the battlefield”. The problem for many modern armies is getting the queen to the battlefield.

The strategic and operational mobility of MBTs and other heavily armoured vehicles must be factored into current and future operations.

The main battle tank, as it currently exists, may be thought of as a weapon system for bad neighbours.

In the offensive role, heavy tanks have proved most strategically effective when the combatants have shared a common land border. Of course, some armies have been willing to cross another nation’s territory to reach their objectives!

The use of tanks becomes more problematic when the adversaries are separated by a body of water, or even occupy different land masses.

Only a few models of transport aircraft can carry vehicles as massive as a main battle tank, and such aircraft are generally held in only modest numbers.

Moving MBTs by sea may take days, or even weeks. Even the largest of the world’s militaries have relatively few LSTs, LCACs or other vessels that can land tanks without port facilities.

Even if a nation sharing a border with an adversary agrees to act as a staging area for an invasion, the mustering of a significantly useful number of MBTs is likely to be slow.

In the meantime, the genocide, human rights abuses or misappropriation of resources that may have been the reason for the military action will continue and claim more victims.

The enemy is likely to use the time to further strengthen their defences and preparations, or make good their escape.

Often the defending nation will have a numerical advantage in both tanks and anti-tank systems.

For some territories, the vast distances involved reduce the usefulness of MBTs.

A strategic objective may be hundreds of kilometres from a port or landing area.

If a tank can only move under its own power, or by rail or road transporter, it may not reach an area until after the fight has moved on.

Main Battle Tanks may also be too heavy for many of the civilian bridges and roadways they encounter.

Richard Simpkin, in his book “Race to the Swift”, writing during the Cold War, notes on p62:

“In developed countries, most of all perhaps in developing ones, there is a tremendous military advantage in keeping within the width of the largest commercial and agricultural vehicles. Gross vehicle mass (MLC) of routes is also important here, both directly and because especially in tracked vehicles, width marches with it.”

On p.80 Simpkin notes that the West German road system had only one east-west route of MLC 50 or higher capable of taking tanks that was available to each NATO division.

Simpkin suggests that combat vehicles be designed within a top limit of 38 tonnes (Just over MLC 40. MLC value is based a number of factors but is approximately vehicle mass in “short tons” of 2,000 lbs, (approximately 90% of a metric tonne).

Vehicle width probably has a little more design leeway. Commercial width is 2.75 metres in many European nations, which is the same as that of an Alvis Stormer AFV, and more than that of a M113.

Incidentally, the medium (30 tonnes) Argentinian TAM tank was designed to be compatible with that nation’s infrastructure including its roads, rail systems and bridges.

Simpkin notes in “Tank Warfare” that a 25% saving in tank mass not only improves operational mobility, but would yield a 62% saving in logistic and engineering resources.

As an offensive system in the modern world, the main battle tank clearly has limitations. This is particularly the case when the desire is to project military power beyond the immediate neighbouring territory.

It is as a defensive or counter-offensive system that the current form of heavy MBT is likely to prove most useful.

For this role, the MBT needs to be within or close to an area an enemy is likely to enter. If this can be achieved, heavy tanks may still prove to be very effective, maintaining their status as “battlefield bully”.

In the future, the primary use of heavy “bull” MBTs may be as a counter-offensive asset for defence of a homeland.

Tank forces are likely to be garrisoned within easy reach of the seat of government and other strategically significant areas that will need to be defended.

Administrations and other high-value targets tend to be located in cities.

The primary defensive/counter-offensive role of MBTs may lead to further adaptations to facilitate operations in urban terrain.

Dozer blades will have numerous applications.

Design emphasis of heavy MBTs may shift to prioritizing firepower and protection over speed/mobility.

Projection of conventional military power may require more strategically-mobile vehicles, or utilize other means of military force.

The former will require a family of vehicles that can be easily air-transported, and preferably capable of air-drop and LAPES insertion.

If some, or all of these systems may be moved by heavy-lift helicopter, so much the better!

In some parts of the world extensive areas of alluvial soils limit vehicle mass to 10 to 20 tonnes.

Variants of such a light vehicle would include personnel carriers, anti-tank systems, engineering and fire-support.

Turrets

The modern main battle tank (MBT) has become too heavy. Its mass adversely affects its strategic deployability and operational mobility.

Tanks and related vehicles of around 36 to 38 tonnes would not only address this, but produce a considerable saving in logistic and engineering support.

In “Tank Warfare”, Simpkin estimates that a 25% reduction in tank mass represents a 62% saving in logistics and engineering.

Less stress on suspensions and drive systems may also improve reliability and reduce maintenance demands.

As discussed by Simpkin in his book “Tank Warfare”, a modern tank does not have much excess fat. We cannot save mass unless something is “hived-off”.

Reducing armour is one option, but is far from ideal.

Reduced protection may be unavoidable for fighting vehicles primarily intended for transport by aircraft.

For more general use combat systems, we want our fighting vehicles to survive long enough to have an effect on a fight. If a vehicle is lost, we want a reasonable chance that the trained crew and passengers may fight another day.

A more productive strategy to reduce mass is to look at the tank’s turret and associated systems.

Many prototype tanks, or proposed tank substitutes, feature an externally mounted gun.

Very little other equipment is mounted on the external gun turret so the system’s narrow frontal profile is emphasised.

In actual practice, as a tank fires on one target, it will probably be presenting the turret’s side to another enemy. The side of a turret has a high probability of taking fire. A thin cross-section with a vertical face is not the best configuration for a turret side!

Smart tankers like to operate from a hull-down position, so the sides and front of the turret are the areas most likely to take fire. On a conventional tank the turret front and sides are understandably often some of the most heavily armoured areas of a tank.

A conventional tank turret contains more than just a gun and some crewmen. There will be searchlights, sensors, active protection systems, smoke-dischargers, and at least one machine gun, to name just a few items.

Once such systems, and a realistic level of armour is added, the external gun mount begins to look much more conventional.

The actual saving in mass and bulk that the external gun provides is considerably less than was advertised.

Another approach is to just eliminate the turret and most of the associated systems. This approach, and its historical precedents, are discussed in more detail here.

A smaller gun permits a lighter, smaller turret and the associated systems needed to move the gun and turret. This avenue is explored in my Thunderback proposal.

The reduced “tank-killing” potential of the main gun is compensated for by also arming the vehicle with anti-tank missile systems.

In the best tradition of a bully, the automatic cannon would mainly come into use after enemy tanks and anti-tank systems have been neutralized.

The higher degree of elevation a lighter main gun permits allows the tank to contribute to combat against helicopters operating outside machine gun and light cannon range.

How Armoured Vehicles May Survive

Tanks and other armoured vehicles are not likely to disappear any time soon.

Something needs to move the infantrymen and their missiles.

Precision artillery systems need something to move their launchers and ammunition.

In the future, more reconnaissance may be conducted by unmanned systems, but these will still need some form of vehicle as a “mothership”.

Changing conditions mean armoured vehicles will need to evolve.

Some of these changes will be “behavioural”.

Future fighting vehicles may be considerably “shyer”, unlikely to expose themselves to direct-fire unless an enemy has already been engaged.

VLS, automatic grenade launchers and mortars will allow vehicles to fire from behind cover.

To survive a future combat environment, a force of vehicle-mounted troops will need a mixture of capabilities.

A future vehicle formation is likely to be preceded by a screen of unmanned reconnaissance systems of various types.

Small units of dismounted infantry will investigate potential threats discovered by the drones. These “dismounts” may use transportation such as e-bikes or skis where practical.

Ironically, the survival of a unit of military vehicles may depend on its infantry’s willingness to dismount.

Dismounts may provide a defensive screen for vehicles when on the move or when halted.

They can locate, and if necessary, assault enemy infantry or anti-tank positions.

Where there is a strong chance of ambush, a force of lightly equipped but well-armed infantry may scout ahead of the vehicles, the latter moving in short bounds, ready to support the dismounts.

Military vehicles are well-equipped with automatic cannon and machine guns. Missile-equipped infantry engaging such a force are likely to make use of entrenchments or similar cover.

To counter this, a mechanized force should include some indirect-fire and smoke capability, such as the mortar-tanks and gun-mortar-armed IFVs described in another article.

Air-burst ammunition for autocannons and grenade launchers will also prove useful against infantry in cover.

A trend seen in many Eastern European AFV upgrades is to supplement MG and cannon armament with an automatic grenade launcher. This provides an individual vehicle with the capability to engage a threat with both high-angle and direct-fire.

Military vehicles are threatened not just by infantry with missiles.

Precision weapons launched by aircraft and artillery are also threats.

The reconnaissance screen on the ground may detect infantry forces but aircraft and artillery may strike from a greater distance.

Automatic weaponry and network-coordinated fire-control (STC) will force aircraft to keep their distance, giving more time to react to air-launched weapons.

Certain armies neglect their air-defence capability, assuming they will always enjoy air-superiority. Other armies are likely to have a different approach.

Many air-defence systems are also effective at suppressing ground targets such as infantry tank hunters.

If you cannot neutralize the enemy firing at you, you may be able to neutralize the enemy’s fire.

Active protection systems for vehicles are already in use. These use explosive charges or radio signals to prematurely detonate incoming explosive projectiles. Many of these are for individual vehicles but some Russian systems such as the SPR-2/-3 have an effect area of several hundred metres radius.

Future vehicle formations may include several C-RAM (Counter Rocket, Artillery and Mortar) vehicles that use various means to defend the force against incoming projectiles.

This will probably be a combination of jammers, decoys, directed-energy and conventional weapons.

These vehicles may have additional air-defence and fire-support roles.

Design Suggestions for Future Armoured Vehicles

The level of protection of a future combat vehicle needs careful consideration.

With current materials, it is impractical to armour a vehicle enough to make it impervious to all of the threats it may currently encounter.

Many of our current systems are already too heavy.

These heavy vehicles are too slow and fuel-thirsty to pursue lighter forces, and too heavy to airlift into more favourable positions.

In another article, I wrote about the possibility of a diminishing returns effect with personal armour. Possibly a similar phenomenon may occur with vehicles.

Attempting to increase protection beyond certain levels may result in relative small improvements in protection while creating a bigger, heavier and less mobile target that is more likely to be hit.

Armour should not compromise mobility, visibility or effective firepower.

Effective future combat vehicles may resemble the BMP-64

Optimal Armouring

In the section on Optimal Armoring, this article argues that it is not cost-effective to passively armour a vehicle against large-calibre or dedicated anti-tank weapons.

More practical and more useful is to give a vehicle SAF-HE/F protection against area weapons, which are the most ubiquitous threat in modern combat.

At the minimum, a first-line combat vehicles should have all round protection from 155mm shell fragments, 120mm mortar fragments and 14.5mm API and HEI machine gun fire.

Features should also be included that increase resistance to mines, IEDs and other nearby explosions.

Probably all military vehicles should incorporate such features, not just the “fighting” vehicles. Some support vehicles may only be at SAF-HE/F-level if fitted with a “B-kit” of modular armour.

Full SAF-HE/F protection may not be practical for light or wheeled vehicles.

Heavy or tracked platforms may find it practical to increase protection levels to that which can withstand 20mm and 23mm cannon fire. Frontal armour and key components may be sufficiently armoured to withstand 30x165mm APDS cannon fire. (“SAF-HE/F+”) Armour that only protects against fragements and rifle-calibre projectiles might be termed “SAF-HE/F- (minus)”.

Passive armour sufficient to defeat all anti‑armour attacks may not be practical.

It should be kept in mind, however, that the effects of a successfully penetrating attack may be highly variable. Resultant secondary effects may range from catastrophic to minor. (“Antitank” by Richard E. Simpkin, p.60-61) In Vietnam, an RPG penetration of an M113 was estimated to have only a 0.8 chance of causing a single casualty. Only one in seven hits managed to penetrate, so the chances of each hit causing a single casualty was less than 12%!

Various design strategies may be utilized to reduce the secondary effects of a penetration. Simpkin (Antitank p.79 and “Tank Warfare” p.116) notes that the low flammability of DERV and AVTUR(JP3) fuel and water allows them to reduce the secondary effects of some penetrative attacks. Certain vehicles place fuel in lightly armoured, self-sealing fuel cells outside the primary armoured envelope. The hydrogen in fuels and water also provides shielding against neutron radiation.

Internal components and structures should be constructed to reduce the danger from fragments and secondary missiles.

Passive armour sufficient to defeat ATGW attack may not be practical, but given the weapon systems’ ubiquity, the capability to be able to resist multiple hits from RPG-2 and RPG-7s would be desirable.

Integral to tank, APC and IFV designs would be net and bar-armour, and other passive and active defensive measures against these commonly encountered weapons. (“SAF-HE/RPG/F” or “SAF-HE/RPG/F+”)

By significantly reducing the potential threat posed by RPGs, the enemy will be forced to seek more expensive, less mobile and less readily available weapon systems.

Since damage will always be a possibility, there should be strategies to minimize its effects. Locate components where they are least likely to take damage, and design systems with a high level of redundancy. Components would be modular, multiple-function and easily replaced.

Armouring individual components may prove more efficient than thickening outer armour over empty airspaces. Individually armoured internal components would decrease the risk to crews from fragments resulting from a penetrative attack.

Designed into a vehicle from the start should be features such as spaced and sloped armour and the provision to accommodate the weight of additional modular armour.

A desirable feature of future families of military vehicles would be a reduced logistical and maintenance appetite. Hybrid-electric propulsive systems and regenerative braking should be utilized for quieter, more efficient and more economical operation. Using both power sources together may boost acceleration, reducing exposure time when moving between areas of cover, or emerging, firing and retreating back behind cover.

An electric-powered supercharger, turbocharger or twincharger may further improve performance in this area.

In some hybrid-electric systems the combustion engine is only there to generate electricity. It has no mechanical connection to the running gear. Potentially, this allows the generator/engine to be replaced with another model better suited to the fuel available. Where the weight penalty is not significant, a large vehicle might mount more than one type of engine.

Attacking a vehicle requires an attacker to acquire, identify and engage a target. Numerous factors influence this, including the inertial of a heavyweight weapon mount and a long time of flight. When possible, a vehicle’s movement exposure time for crossing an area of partial cover is shorter than the time needed to acquire, identify and engage it.

The ability to sprint quickly across a short distance (“tactical/battlefield mobility”) will be more useful to a tank than a sustained high cross-country speed.

Improvements in reliability, ease of repair and maintenance should be design priorities.

Where practical, existing components and systems from commonly encountered sources should be utilized.

Damaged elements should be capable of easy repair or replacement, preferably from commonly available supplies.

In this article, Simpkin proposes a vehicle design with a separate chassis and running gear. Such as structure might make use of geodetic construction.

A standard vehicle model within a formation facilitates cannibalization.

A common design that may be used for a wide variety of roles also lowers development and production costs.

Defences such as passive armour may be supplemented by other systems such as active protection, smoke, jammers and explosive reactive armour (ERA).

Such systems are finite, however, and tactical responses must recognize that swarm or saturation tactics may be used to overwhelm them.

Defence also involves good use of any available terrain features for cover and concealment.

We may see increased use of large-scale smoke screens in situations where suitable cover is rare.

The ability to tactically use terrain will depend on the vehicle’s mobility and size.

The better a vehicle’s cross-country capability. the more options it has.

Ground may be mashed up by artillery fire or be soft-mud or sand, so tracks are the most logical choice.

Some early tracked vehicles could be used without their tracks fitted. This may be an idea to re-examine.

The dogma that tracks are less reliable than wheeled vehicles seems to be based on 1940s’ technology. I would not be surprised to discover that modern tracked systems are more reliable than the 30+ ton wheeled vehicles in current vogue. Wheeled systems with close coupled axles tend to be more expensive and labour intensive than tracks.

The larger and heavier a vehicle is, the less options it has. A relatively compact vehicle is more agile in close terrain such as urban areas.

The LAV Stryker, Boxer and similar vehicles are too big for many applications and of dubious utility compared to conventional trucks.

This said, some current vehicles such as the HMMWV and most of its proposed replacements are too small.

An infantry carrier should have a cargo capacity of around two tons. With weapons, equipment, ammunition, food and water, each infantryman must constitute at least 200-250 lbs of load.

From a good design of infantry carrier may be derived a variety of useful variants. This includes reconnaissance vehicles, tanks, command vehicles, mortar-carriers, air-defence, drone-carriers, C-RAM, cargo, tankers, engineer, maintenance, recovery, flatbeds and others.

For more on infantry carrier design, see the sister page of this article.

While the HMMWV is too small and underpowered for use as an infantry carrier, it is used for other roles that it is too big for.

This article gives a good account of the HMMWV’s weaknesses as a reconnaissance platform.

Vehicles such as Toyota Land Cruisers and Hiluxes can more cost-effectively perform many of the non-combat roles that HMMWVs are used for.

In this article I suggest that a Toyota “mimic” vehicle may prove a useful supplement to more overtly military tracked reconnaissance vehicles.

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