155mm Gun Tank T58

U.S.A. (1952)
Heavy Tank Prototype – 2 built

n the early 1950s, the American military’s quest for a powerful new heavy tank was well underway. The T28, T29, T30, T32, and T34 projects had all ceased in favor of the 120mm Gun Tank T43, which eventually became America’s last heavy tank, the M103.

While still in development as the T43, however, there were parallel projects competing for the role of America’s next heavy tank. One of these projects was the 120mm Gun Tank T57. It used the same hull as the T43, but incorporated new technologies for the turret. The turret was of the oscillating kind, but it was also outfitted with an autoloading mechanism.

In the Army Development Guide of December 1950, both the T43 and T57 were expected to more than meet the requirements of the military and be a worthy adversary of Soviet armor such as the infamous IS-3. However, in the Tripartite Conference of Armor and Bridging of October in 1951, it was recommended that a 155mm gun armed tank be developed instead.

A mockup of the T58 Heavy Tank. Photo: Presidio Press

Development

A list of recommended characteristics for this new heavy tank was outlined in a paper on the 18th of January 1952. Such recommendations included a gun that exclusively fired HEAT (High-Explosive Anti-Tank) or HEP (High-Explosive, Plastic. Otherwise known as HESH – High-Explosive Squash Head) rounds. This paper also recommended the construction of two prototype turrets complete with autoloaders and 155mm guns for installation on T43E1 chassis. The resulting vehicle received the designation of 155mm Gun Tank T58.

On the 10th of April 1952, a contract was drawn up with United Shoe Machinery Corporation of Beverly, Massachusetts for the design, development and manufacture of the two pilot turrets.

Hull

The hull that was used for the project was the same as that of the 120mm Gun Tank T43, which would later be serialized as the M103, America’s last heavy tank. Armor on the hull was the same. The cast ‘beak’ was 3.9 – 5.1 in (100 to 130 mm) thick.

An 810hp Continental AV1790 12-cylinder air-cooled gasoline engine propelled this chassis to a speed of around 21 mph (34 km/h). The tank’s weight was supported on seven road wheels attached to torsion bar suspension. The drive sprocket was at the rear while the idler wheel was at the front. The idler wheel was of the compensating type, meaning it was attached to the closest roadwheel by an actuating arm. When the roadwheel reacts to terrain the idler is pushed out or pulled in, keeping constant track tension. The return of the track was supported by six rollers.

Turret

The T58’s turret was one of the largest oscillating turrets ever designed, at approximately ¾ the length of the hull. Changes had to be made to the T43/M103 hull to accommodate the new large turret. When initially tested on one of the hulls, the turret bustle would collide with the mufflers of the main engine and auxiliary generator located on the engine deck. To fix this issue, the mufflers were relocated 20-inches (51cm) to the rear. A new travel lock was added to the deck to accommodate the larger gun.

This turret had similarities to the T69 medium tank prototype, in that its roof had multiples ways of ingress and egress. The turret roof was constructed from two removable plates. The rear plate was bolted in place, while the front section, like the T69, was hinged and could be opened outward by use of a hydraulic piston. The large opening made it easier to exit the turret in an emergency. In the open position, this opened section also provided a shield for the crew while evacuating. These sections were designed to be easily removed to permit installation of the autoloader mechanism and other components.

A ventilator was placed at the rear-right of the turret atop the bustle to vent gases and smoke produced when the gun is fired.

Line drawing of a face-on view of the T58. Note the size of the turret. Photo: Presidio Press

Armament

Originally, it was planned to utilize the 155mm Gun T80. This proved unnecessary as the chosen ammunition for the gun was of the chemical type and did not require the high-velocity granted by the T80. Designers instead opted for a lighter weight version of the lower velocity 155mm Gun T7, the gun developed for the Heavy Tank T30. Firing HEAT through this gun, the maximum armor that could be penetrated (angled at 0 degrees) was 16 inches (406mm).

This modified version of the T7 was originally designated as the 155mm Gun Howitzer T7E2. It was later changed, however, to ‘155mm Gun Howitzer T180’. There was no actual change to the gun, just a change in nomenclature. The T180 differed greatly from the original T7 though. The breech block was changed from a horizontal to a vertically sliding type. A bore evacuator (fume extractor) was added towards the end of the gun, and a T-shaped blast deflector installed on the muzzle. The gun tube wall was thickened and the chamber lengthened about an inch (~25mm) to accommodate the plastic closing plugs used on the cartridge cases of the two-part ammunition.

Unlike the T57 that had a rigidly mounted gun, the T58 was outfitted with a four-cylinder hydro spring recoil system in a mount designated the T170. There were 2 springs to each side of the breach. To save space and remove the need of extending the length of the turret, the recoil of the gun was limited at 12 to 14 inches.

Secondary armament consisted of a coaxial .30 Cal (7.62mm) Browning machine gun, and a .50 cal (12.7mm) Browning heavy machine gun mounted atop the commander’s cupola. The oscillating turret provided an elevation of 15 degrees, with a depression of 8 degrees. The original specifications included a second coaxial machine gun, but this was not included.

The main gun was aimed via periscopic sights. There was one lens on each side of the turret, known as ‘frog’s eyes’. These types of sights were used on many American tanks from the early 1950s onwards, including such tanks as the T69, M48 and M60.

The armor on both the collar and upper part the turret was extremely thick, but exact measurements are unfortunately unknown.

A cut-away view of the inside of the T58’s turret. Photo: Presidio Press

Autoloader

The 155mm gun was fed by an autoloading mechanism located in the turret bustle. It was not too dissimilar to the one used on the T69 medium tank prototype, consisting of a 6-round cylinder magazine with an incorporated rammer. On the T69, it actuated up and down during the loading sequence. On the T58, due to the size and sheer weight of a fully loaded magazine, the cylinder was fixed in place.

Two diagrams looking at the front and back of the auto-loading mechanism. Photo: Presidio Press

The loading sequence was thus: The loader used an internal, electrically powered hoist attached to the turret roof to remove one of the 95 pound (45kg) shells from the ready rack and insert it into the loading tray of the cylinder. The round was then slid into an empty cylinder chamber. The loader then selected the requested ammo type by manually rotating the cylinder with a hand crank. The separately-loading ammunition (projectile then charge) was rammed into the breach as one unit. After firing, the empty propellant cartridge was ejected back into the cylinder, where it was removed by the loader before the sequence began anew.

Crew

The crew consisted of a Commander, Gunner and Loader located in the turret and Driver in the front of the hull. The Gunner was located at the front right of the turret, the Commander sat behind him under a vision-cupola. The Loader was positioned on the left of the turret under his own hatch.

Fate

Work on two pilot turrets continued into 1956 despite numerous design changes during production and delays in obtaining and producing various parts required for assembly. By this time, however, trends had shifted, and a tank such as the T58 was no longer thought a necessary to the military.

The T58 project, along with the T57 and many other projects, was canceled on the 17th of January 1957. Following this outcome, both pilot turrets were scrapped. All that survives today are a few photos and government reports.

Specifications

Dimensions (L-w-H) 37.14 x 12.34 x 9.45 ft (11.32(oa) x 3.76 x 2.88 m)
Total weight, battle ready Around 62.5 tons (125 000 lbs)
Crew 4 (Commander, Driver, Loaders, Gunner)
Propulsion Continental AV-1790-2 V12, AC Twin-turbo diesel 810 hp.
Transmission General Motors CD-850-3, 2-Fw/1-Rv speed GB
Maximum speed 21 mph (34 km/h) on road
Suspensions Torsion bars
Armament Main: 155mm Gun Howitzer T180 Sec: 1 Browning M2HB 50. cal (12.7mm), 1 cal.30 (7.62 mm) Browning M1919A4
Production 2

Links, Resources & Further Reading

Presido Press, Firepower: A History of the American Heavy Tank, R. P. Hunnicutt
An official US Government report dated April 1954. READ HERE
On History of War

AVGP Grizzly

 Canada (1976)
Armored Personnel Carrier – 265 Built

The AVGP (Armoured Vehicle General Purpose)

Three AFVs, based on the same chassis, were ordered by the Canadian army back in 1976. These were Cougar (fire-support), Husky (ARV) and the Grizzly, an APC. The latter was probably the closest to the six-wheeled version of the Swiss MOWAG Piranha I, on which the vehicles were based. The Grizzly entered service in 1978 but was gradually retired until 2005, being replaced by the LAV III.

Development & Design of the Grizzly

The Grizzly was to be used as an alternative to the M113 for the regular infantry battalions and reserve units. It had a three-man crew and could carry 5-6 infantrymen. It had a Cadillac-Gage 1 metre turret mounting a .50 (12.7 mm) BMG and a 7.62 mm (0.3 in) machine gun. The troops can exit through the rear doors or the roof hatches.

Otherwise, the basic configuration was basically the same as the two other related vehicles, with a 6×6 chassis and sloped welded steel hull. The driver was in front of the vehicle, with a hatch with three vision sights. The central one could be swapped for a night vision sight. The maximum armor thickness for the hull was 10 mm (0.39 in), which provided protection against small arms fire and artillery shell splinters. For mobility, the Grizzly was given a Detroit Diesel 6V53T diesel, which developed 275 hp for a maximum road speed of 100 km/h (60 mph). In water, it could reach a speed of 10 km/h (6 mph) thanks to the two propellers. The vehicle had a 600 km range. It was able to climb a 60% gradient, 30% side slope, 0.8 m vertical step, and a trench about 80 cm wide.

The driver sat in the front left part of the hull. When the infantry soldiers were inside the vehicle, the gunner was seated behind the driver, working on the radio. The commander sat in the turret, manning the turret. However, when the infantry troop dismounted, the commander would accompany them. The gunner would then occupy the turret and the vehicle could act as infantry support or withdraw.

The Cadillac-Gage 1 metre turret was designed for armored vehicles, denominated after its 1-meter turret ring. It was originally armed with a 7.62 mm (0.3 in) machine gun (0.3′) and 12.7 mm machine gun (0.5′ or cal. 50). The only variant of the Canadian AVGP to mount this turret was the Grizzly. It was the smallest possible to keep the vehicle’s interior large enough for the soldiers. When these vehicles were made available to African Union peace-keeping forces operating in Sudan, the latter had to seek permission from the US Government in order to ship them with theses turrets. The other vehicle using it (in US service) was the M1117 4×4 Armored Security Vehicle.

Closeup of the Cadillac Gage 1 meter turret, here with a grenade launcher on the M1117 Armored Security Vehicle.

Active Service

In service, the majority saw their water propulsion removed. The Wheeled LAV Life Extension project saw conversions of the Grizzly (and Husky) into support variants (Command Post, Mobile Repair Team Vehicle). These variants were to be the Command Post (80), Radio Relay (10), Unit Access Nodes (20), Very Short Air Defence (24), Artillery Gun Tractor (18) and Mobile Repair Team (70). But this project was canceled in 2005. In May 2007, the Edmonton Police Service received a single, unarmed Grizzly from the Army.

In June 2005, the Canadian government announced the loan of 105 AVGPs (100 Grizzlys and 5 Huskys) to African peacekeepers in the Darfur region of Sudan. This was a low-intensity conflict, for which the vehicle was of the right size and capability. Civilian contractors were called on to maintain the vehicles. Since US-manufactured or licensed parts were used (mostly the turret), permission was to be required to loan the vehicles. At first, they were to be shipped without their CG turrets, and they arrived in Senegal in late summer 2005, the turrets being shipped later, on November 18, 2005. The loan was originally planned for one year, but it was extended, and transferred from the African Union to the United Nations.

According to Amnesty International, soldiers who used the loaned vehicles had little time for training but gained experience. One of these vehicles was destroyed by an RPG. A second one was damaged when ramming a more heavily armed but unarmored technical. In 2009, Uruguay purchased 98 Grizzlys (and 5 Huskys) previously on loan with the AMIS/UNAMID mission in Darfur.

Front view of a Grizzly at the Commonwealth Air Training Plan Museum

Gallery

Grizzly interior view with the turret removed
AVGP Grizzly during an exercise
Grizzly Extended Platform
30-10-00
grizzly starboard side

 

BMP-23

Bulgaria (1982)
IFV – 50-115 built

The Bulgarian IFV

Small countries, like Bulgaria, are usually not capable to single-handedly develop and build a Main Battle Tank. However, creating an Infantry Fighting Vehicle using existing platforms is far more at hand.

This is exactly what the Bulgarians intended, producing a vehicle tailored to the needs of the Bulgarian Army then under the Soviet sphere of Influence as part of the Warsaw Pact. The overall goal was to have an improved IFV compared to the BMP-1 already in service. Only a few of the resulting BMP-23s were cranked-up by KINTEX State Commercial Enterprise, some sources claiming 50 (Wikipedia), while others claiming 114 (Army-Guide). The vehicles entered service in the early 1980s.

BMP-23 during a parade

Design

General Configuration

The basis for the BMP-23 was the sturdy Soviet 2S1 “Gvozdika” self-propelled howitzer, built under licence in Bulgaria at the time. The Gvozdika itself was based on the multipurpose MT-LB chassis. However, given the goals of the military, it had to be given much sturdier armor than that of the BMP-1. The better engine and reinforced suspension helped in this way.

The hull was also comprehensively modified to integrate a roomy troop compartment at the rear, for six equipped infantrymen seated back-to-back. The rear was modified to accept two doors for dismounting, in addition to the two large roof hatches. Three pistol ports were also placed in the walls, with bulletproof vision devices. The welded steel hull was reinforced with a frontal arc protection of about 20-23 mm (0.8-0.9 in). It is assumed that it is able to withstand 23 mm (0.9 in) AP rounds.

Turret and Armament

Primary
The turret was, of course, the major addition to this vehicle. It has a rounded rear, with flat sides all around and a well-sloped front. Protruding from the turret is a 23 mm (0.9 in) 2A14 automatic cannon. It is the same gun used in the ZU-23-2 light AA gun which equipped the Soviet light AA units. It is fed by 600 rounds, has +80° of elevation, and can fire either HE-IT and AP-IT ammunitions with a muzzle velocity of 970 m/s. This gun, introduced in the 1960s, has a total length of 4.57 m (10 ft) and a barrel length of 2 m (79.1 in), or 87.3 calibers. It fires a 23x152B round, with two rate of fire settings, one low, at 200/300 rounds/min, and one high, at 500 rds/min. The practical range is 2.5 km (2 mi).

Secondary
The armament is completed by a 7.62 mm (0.3 in) machine gun (PKT) coaxial light machine gun, and, in order to deal with tanks at longer ranges, a 9K11 Malyutka ATGM launcher, recently replaced with a 9K111 Fagot. The latter is an SACLOS missile, fitted with a 1.7 kg High Explosive Anti-Tank (HEAT) warhead. The Malyutka can defeat up to 400 mm of RHA /200 mm 60° sloped armor up to 2,500 m. The Fagot is claimed to be effective up to 4,000 m and has tandem HEAT rounds. The mount is electrically operated from inside, with 90° of traverse and -5 to +15° elevation. In addition, the crew carried their personal AK-47s, RPG-7V, and RPG-22, plus a Strela-2M for AA cover.

Sights

For targeting, the gunner, who sat on the left, has a binocular day sight with a magnification of ×4.5 and a 40° field of view. He can use a forward-opening hatch cover and a white light searchlight. The commander, on the right, has a cupola with single-piece hatch cover opening to the front and mounting an infra-red searchlight. He also has his own 1PZ-3 monocular sight, TKN-3B day/night sight with a ×4.75/×4 day/night magnification. These sights were produced under license by the Vazov Engineering Plant in Sopot, Bulgaria.

Mobility

Mobility-wise, the BMP-23 is given an improved engine, the turbocharged diesel YaMZ-238N, which develops 315 hp, giving the vehicle a 62 km/h (39 mph) top speed on road and 550 to 600 km (340-370 mi) operational range on average. The drivetrain is shared with the MT-LB and Gvozdika, with a full row of seven evenly spaced rubberized road wheels without return rollers. The drive sprocket is at the front and idler at the rear. Each road wheel is suspended on a torsion bar. In addition, the first and last suspensions units came with hydraulic shock-absorbers.

Equipment

For concealment, the usual exhaust smoke ejector is used. However, two banks of three 81 mm electrically operated smoke dischargers were added on the modernized BMP-23D version. Importantly, the BMP-23 retains the amphibious characteristics for the MT-LB, with enough buoyancy to swim, propelled and guided by the tracks. Preparation for going into water includes raising the trim vane and removing the hull sides slotted mudguards. Fire detection and suppression systems are installed. It is also fitted with R-123M VHF radio and R-124 tank intercom and an NBC collective protection with GO-27 radiation and chemical detection system.

Variants

-BMP-23D: Upgraded model with the 9K111 Fagot ATGM plus 2×3 81mm smoke grenade launchers.
-BRM-23: Reconnaissance vehicle, apparently entering service in limited numbers in 1991, equipped with a large folded antenna mounted on the rear of the vehicle.
-BMP-30: A prototype was built using a turret very similar to the one seen on the BMP-2. Only 10 built in 1995 according to Army-Guide. It has a 2A42 30 mm (1.18 in) autocannon with 4000 m range, coaxial PKT and AT-5 Spandrel ATGM.

The BMP-23 in Service

The BMP-23 was first publicly revealed at a parade in 1984. It served its tour of duty in Iraq along with the M1117 Armoured Security Vehicle, without any noticeable events taking place. The BMP-23D is still in service today in the Bulgarian Army. There is an interesting “recycling” potential for nations willing to get rid of their old 2S1 Gvozdika SPGs and transform them into anIFV more potent than the BMP-1.

Camouflaged BMP-23D BULAF, Iraq, 2000s.

Links/sources

The BMP-23 on Wikipedia
On Military-Today
On TankNutDave
The BMP-30 on Army-Guide

BMP-23 Specifications

Dimensions 7.28x 3.05x 2.53 m
23’11” x10′ x8’4”
Total weight, battle ready 15.2 tonnes (33,510 lbs)
Crew 3+7 (driver, gunner, commander, 7 infantry)
Propulsion Turbodiesel YaMZ-238N, 315 hp, 20.7 hp/t
Suspension Torsion bars, shock dampers
Speed (road) 62 km/h (39 mph)
Range 550 km (340 mi)
Armament 23 mm (0.9 in) 2A14 autocannon
9K111 ATGM “Fagot”
7.62 mm (0.3 in) PKT LMG
Armor About 20 mm front (0.79 in)
Total production 50-114 in 1982-1992

Begleitpanzer 57

Western Germany (1977)
IFV Prototype – 1 Built

Believing they had identified a niche in the market, the Thyssen-Henschel and Bofors companies began a private venture (without funding or official support from the West-German military) to develop an ‘Infantry Escort Vehicle’.

The resulting vehicle, debuted in November 1977, was based on a modified hull of the recently introduced Marder IFV (Infantry Fighting Vehicle). It was designated the Begleitpanzer (Accompanying Tank) 57 and was classified as an Armored Infantry Fire Support Vehicle, or ‘AIFSV’.


Side on schematics of the vehicle with turret straight forward and turned 90 Degrees to the left.

The Marder

The Marder (German word for the weasel-like creature, the Marten) IFV entered service with the West German army or ‘Bundeswehr’ in 1971. It was developed as part of the rebuilding effort of Germany’s armored vehicle manufacturing industry. Though it was not a remarkable vehicle according to its features, the design has succeeded in being a versatile and well rounded IFV. It was a simple vehicle that had armor up to 20mm thick over the frontal arc, with the frontal upper plate steeply angled. This frontal plate was designed to withstand 20mm Armor-Piercing Discarding Sabot (APDS) rounds. It had rear access doors for carried infantry to disembark from and rifle ports in the hull side which allowed the infantry to fire through, while safely inside.

It had a small two-man turret which carried the IFV’s main armament, a 20mm Rheinmetall MK 20 Rh202 autocannon and a coaxial 7.62 mm MG3 machine gun. The 20mm can fire either Armor-Piercing (AP) or High-Explosive (HE) round.

The IFV was powered by an MTU MB 833 Ea-500 diesel engine, which developed 591 hp. This propelled the vehicle to a top speed of 47 mph (75 km/h) on road. It runs on six road-wheels connected to a torsion bar suspension. The idler wheel is located at the rear, with the drive sprocket at the front.

A view of the rear of the single Begleitpanzer prototype. Photo: topwar.ru

Design of the Begleitpanzer

The overall design of the vehicle was largely unchanged from the original Marder IFV. As such, the engine, transmission, suspension, tracks, and armor remained the same. The biggest modification to the Marder chassis was the replacement of the standard turret with a larger one mounting the vehicle’s main armament which consisted of an automatically cycling Bofors 57mm (2.24in) L70 Mk.1 gun, traditionally used in the anti-aircraft role on ships. This necessitated internal modifications. The entirety of the gun was open to the elements. When the gun was depressed the breach would rise out of the turret when elevated it would sink inside the hull. Depression/elevation range was – 8 to + 45 degrees. There was also a coaxial MG3 machine gun mounted on the right side of the main gun. The gun was fed from an ammunition can mounted on the gun cradle, meaning it would have to be reloaded from outside the tank. This gun was intended to engage with lightly armored enemy vehicles and troops.

Front view of the vehicle showng the well angled upper plate. Photo: topwar.ru

The weapon was mounted centrally in the uneven turret. The left of the turret was raised to accommodate the commander’s position. Above this position was a periscope ring for all-round observation. The right half of the turret was much lower to accommodate the vehicle’s secondary armament, a Tube-launched, Optically-tracked, Wire-guided (TOW) Anti-Tank Guided Missile (ATGM) launcher, which could fire the BGM-71B missile. This was installed to give the vehicle some anti-armor capability. After firing, the launcher tube rotated backward until it was vertical, and the exhaust end was in line with the turret roof. A small circular hatch would then open. Through this, a fresh ATGM would be loaded in. The tube would then rotate back to firing position. The gunner was located underneath the ATGM launcher tube. He operated both the main gun and the ATGM with controls in his position.

Two loaders were positioned in the rear of the tank. The loader on the left would be responsible for loading clips into the 57mm main gun. The loader on the right would be responsible for handling the ATGMs. The ammunition load-out consisted of 48 rounds for the 57mm gun and 6 TOW-ATGMs. The driver was located at the front left of the vehicle.

Fate

A mock-up of the Begleitpanzer was displayed in November 1977. A prototype was tested in 1978. Due to a lack of interest from the German Military, the project was not accepted for construction.

The project did start a string of other attempts to increase the lethality of the Marder. A similar project by Thyssen-Henschel saw the addition of a 105mm L7 gun, as found on Leopard 1

, to the top of the Marder chassis. This was designated the VTS1, but like the Begleitpanzer, it did not progress past prototype stages.

Gepard Specifications

Dimensions (L-W-H) 6.79 m x 3.24 m x 2.98 m
(22′ 3″ x 10′ 8″ x 9′ 9″)
Total weight, battle ready Aprx. 33.5 tons
Crew 5 (driver, commander, gunner, x2 loaders)
Propulsion MTU MB 833 Ea-500 diesel, 561 hp.
Suspension Independent torsion bars
Speed (road) 47 mph (75 km/h)
Armament Bofors 57mm (2.24 in) L70 Mk.1
Armor 20mm (0.78 in)
Total Production 1 Prototype

Links, Resources & Further Reading

Arms and Armour Press, Tanks of the World 1983, Ferdinand Von Senger.
On topwar.ru

Medium/Heavy Tank M26 Pershing

U.S.A. (1944)
Medium/Heavy Tank – 2,212 Built

A Bit Late for WWII

The M26 Pershing descended from a long series of medium and heavy tank prototypes, dating back from 1936. During the war, heavy tank development had been long delayed or given low priority since the US Army, USMC and Allied forces required a mass-built, good-all-around medium tank, which took the shape of the Medium M4 Sherman.

By 1944, the High Command was aware of the limitation of the M4 when facing German tanks. By mid-1944, both the British and US had undertaken upgrades in armor and guns on the Sherman, and developed tank-hunters instead of mass-producing a brand new model. However, by the fall of 1944, these stopgap measures proved insufficient, and the innovative M26 was eventually pushed forward for production. But it was a bit too late. The Pershing saw little combat and mostly soldiered during the Cold War, starting with Korea. At last, the crews had the ideal tank to deal with German armor, but historians and authors still debate about the causes of such delays. Could the Pershing have been a game changer if introduced earlier?

T20 Prototype (1942)

Development of the T20 Medium Tank started as an upgrade over the M4 in 1942. This new tank had common features with earlier models, notably the characteristic suspension (HVSS) bogies, roadwheels, return rollers, drive sprockets and idlers. By May 1942, a mock-up of the T20 had been already produced. U.S. Army Ordnance also ordered the development of the M6 heavy tank, which would prove a dead end. The main feature of the T20 was the lower silhouette and more compact hull, allowed by the availability of the new Ford GAN V-8 combined with a rear transmission and rear sprocket drive layout.

This engine was an early attempt to produce a V12 with similar layout and performances to the Rolls Royce Merlin, but development was stopped and the engine was turned into a smaller V8. Other improvements included a sturdier horizontal volute spring suspension (HVSS), a longer barrel version of the 75 mm (2.95 in) (M1A1), and 76.2 mm (3 in) front armor. The weight and width were very similar to the M4, allowing transportation in similar conditions. However, the T20 also pioneered the Torqmatic transmission, which proved highly problematic during trials.

T22 and T23 Prototypes

Problems with the Torqmatic dictated a return to the M4 transmission, leading to the T22. Variants of this medium tank also tested an autoloader, thus reducing the turret crew to just two.

T-23 at Aberdeen

In 1943, the need to replace the M4 was not apparent, and the U.S. Army Ordnance decided to test several electrical systems on the next T23 Medium Tank, mainly the transmission. These entered service but, because of maintenance and supply problems, only operated on U.S. soil for the duration of the war, mainly for training purposes.

T23 prototype with electrical transmission

The T25 and T26

The T25 was a new design, up-armored and up-gunned. This was done as it was clear, after the first encounters with German upgraded Panzer IVs, Panthers and Tigers, that the M4 was less up to the task than previously thought. The debate was heated, but finally, a breach opened and clear-cut decisions were taken after the reports came from Normandy. Meanwhile, a series of T25s was built, inaugurating a new, far larger cast turret derived from the one on the T23, in order to accommodate a 90 mm (3.54 in) gun.

T25 prototype

The T26 added upgraded armor to the mix, with a new 102 mm (4 in) thick glacis and reinforced hull. Their overall weight rose to 36 tonnes (40 short tons), up into the category of “heavy tanks”.

Performance decreased, and triggered reliability and maintenance issues, as their engine and transmission were not designed to cope with the additional stress. The T25 displayed VVSS suspensions while the T26 used the final torsion bar system retained on the M26. The T26E1 was the prototype upon which the upgraded production version T26E3 was based on. After a small pre-series, this was standardized as the M26.

M26 Design

M26 Pershing 4-view drawing

Compared to the Sherman and previous models, the Pershing was revolutionary. The new Wright engine and short transmission gave it a low profile, as opposed to the Sherman. The glacis plate was one of the thickest ever fitted on an American tank to that point. The torsion bar system conferred a noticeably better ride and was leagues ahead of the tractor-based VVSS, as well as simpler than the HVSS. The large tracks fitted with soft steel shoes contributed to lowering the ground pressure and giving better grip on soft terrain. Above them, two wide mudguards mounted large storage bins for tooling, spares and equipment.

The drivetrain, modeled and tested on the T26, counted six pairs of rubberized roadwheels, each fitted on its own wheelarm. They were connected to the torsion bars by the way of an eclectic spindle, and each was also connected to a bumpstop, which limited the motion of the arm. Three out of the six received extra shock absorbers. There was also one idler (identical to the roadwheels) at the front and one sprocket at the rear, on each side.

The idlers could be precisely adjusted to the track thanks to a large notch. This meant that the idler could be displaced forward or backward and thus change the track tension. There were also five return rollers. The tracks were a new model, but rather classic in appearance, each link being articulated with wedge bolts and having a two-piece center guide. These were also rubberized.

Construction called for large cast sections, front and rear, attached to the hull sides and welded together. Another cast section went across the engine deck for better strength. There was an infantry telephone fitted on the back panel of the engine compartment, inside an armored box. Infantrymen could then communicate with the tank, for close support, even in the midst of battle.

The engine compartment was covered by eight armored grids, four openings total, only accessible when the turret was turned to the side. The two rearward ones granted access to the engine, while the two forward ones allowed access to the left and right fuel tanks, the right being shorter to make room for the auxiliary engine and electric generator. There was also a semi-automatic fire extinguishing system. Also on the engine deck was located the radiator filler cap and gun travel lock. The transmission had three speeds forward and one reverse. The differential operated three drumbrakes on each side.

The M36 commander’s cupola had a one piece hatch and six direct vision prisms made of thick bulletproof glass, inserted inside the cupola bulge. In practice, the hatch had the tendency to jump loose and a field experiment later passed into general practice consisted of drilling holes into it. The top of the hatch mounted a periscope and the entire structure moved freely around a fixed azimuth scale. When inside, the commander had a lever for traversing the turret left or right. Just behind him was mounted the SCR 5-28 radio set. Due to its lengthwise position, a mirror allowed the commander to use the commands at hand. The gunner had an M10 periscope, with x6 magnification, and to its left was an M71 auxiliary telescope with x4 magnification.

The M3 90 mm (3.54 in) gun was power traversed, with a joystick controlling elevation and a pump for manual traverse. The gun also had an elevation handle and, just behind it, a manual trigger, in case of failure of the electrical fire system. There was also a gear change lever, for choosing between the manual or hydraulic options for traverse. At a lower position was found the manual traverse lock, which was used when the turret was reversed and gun lowered and attached for transportation. The gun had a classic percussion fire system and manual breech. The loader also fired the cal.30 (7.62 mm) coaxial machine gun, and had his own vision system. Just left of him were the ready racks, storing ten rounds of various types for immediate use. Additional stowage inside six floor compartments was used. He also had a pistol port.

The driver and assistant driver both had sprung suspended seats and single-piece hatches. The driver had a rotatable periscope, immediate access to the semi-automatic fire extinguisher to his left and a brake release. The instrument panel counted (in order) five circuit breakers, a fuel gauge, a lever for fuel tank selector, electrical starter, electrical gauge, tachometer, personal heater, differential settings, fuel cut-off emergency button, panel light trigger, main lights, speedometer, oil pressure & engine temperature gauges, as well as several lamp indicators.

The two brake levers had no neutral positions. The turning radius was about 20 feet (6 m). The assistant driver was in charge of the bow machine-gun, a ball-mount cal.30 (7.62 mm), and had a complete set of driving levers if needed to replace the driver, and had a simple hatch periscope which allowed him to see his machine-gun tracers. The turret roof also housed, near to the commander cupola, a multi-purpose cal.50 (12.7 mm) heavy machine gun. Ammunition racks for it and the coaxial cal.30 were found inside the turret rear cast “basket”.

Production and Controversy

It is a known fact that the actual production of the T26E3 preseries, which was standardized in March as the M26, only began in November 1944 at the Fischer Tank Arsenal. Only ten were built this first month. Then it raised to 32 in December and gained momentum in January 1945, with 70 vehicles and 132 in February. Added to this, the Detroit Tank Arsenal also joined this effort, releasing some additional tanks in March 1945. From then, around 200 left both factories each month. In total about 2212 vehicles were built, some after WW2. Although months were needed to train crews and maintenance teams, the first real operations began in western Germany in February-March 1945.

The controversy came with the legitimate question about the well-documented inefficiency of the M4 Sherman against German armor after 1944, correlated with the fact that the US Army failed to field a new tank model in time, since the T26 was delayed for so long. Several historians, like Richard P. Hunnicut, Georges Forty and Steven S. Zaloga specifically pointed to the responsibility of the ground forces head, General Lesley McNair, in this matter of fact. Depending on the these opinions, several factors contributed to these delays:

-The development of tank destroyers alongside regular M4s and based on the same chassis (McNair himself developed and strongly supported this doctrine) or the introduction of improved M4s (the 1944 “76” versions).
-The need to have a streamlined and simplified line of supply. Most US tanks at that time were M4s or based on the M4 chassis, sharing the same components. Adding to this a brand new set of parts and a heavier, untested tank, would have imposed many changes and perhaps jeopardized such 3000 miles long (4800 km) supply lines, which became essential from D-Day on.

A state of complacency after the introduction of the M4, as it was seen as superior to German tanks in 1942 and still a match in 1943. Many officers, including Patton himself, were quite happy with the high mobility and reliability of this model, and opposed the introduction of a new heavy type, which was seen as unnecessary. Even when the Tiger and Panther were encountered in limited numbers, the order to study a new model was not given, and instead time was “wasted” on studying a new electric transmission. Only after Normandy were some efforts made to develop a new tank from the T25.

-From Zaloga’s point of view, there was a clear opposition to the development of the T26, only lifted when General Marshall, supported by Eisenhower, overruled McNair in December 1943 and renewed the project, although it proceeded quite slowly. Hunnicut underlines the ordnance requested 500 vehicles of each model in development then, the T23, T25E1 and T26E1, because of contradictory wishes. The Army Ground Forces systematically objected to the 90 mm (3.54 in) armed new heavy tank, while the Armored Forces branch wanted the 90 mm (3.54 in) to be mounted on the Sherman.

The Super Pershing & T26E4

The first combat experience showed that the M26 still fell short on firepower and protection when facing the formidable German Tiger II. Because of this, experiments were carried out with the longer and more powerful T15 gun. The first vehicle, based on the first T26E1-1 vehicle, was shipped to Europe, where it was uparmored and saw limited combat, being now commonly known as the “Super Pershing”. Another T26E4 prototype and 25 “serial” vehicles followed, with slight differences.

Super Pershing, 1945

The M26A1

This modified version came into production after the war and most Pershings in service were upgraded to this standard. It replaced the M3 with the new M3A1 gun, characterized by a more efficient bore evacuator and single-baffle muzzle brake. The M26A1s were produced and modified at Grand Blanc Tank Arsenal (1190 M26A1s in all). They cost $81,324 apiece. M26A1s saw action in Korea.

Active service

Europe

The Army Ground Forces wanted to delay full production until the new T26E3 was battle-proven. So the Zebra Mission was mounted by the Armored Forces Research and Development unit, led by General Gladeon Barnes in January 1945. Twenty vehicles of the first batch were sent in Western Europe, landing at the Belgian port of Antwerp. They would be the only Pershings to see combat in World War Two, spread between the 3rd and 9th Armored Divisions, part of the First Army, although some 310 would be shipped to Europe until V-day. They drew their first blood in late February 1945 in the Roer river sector. A famous duel took place in March at Köln (Cologne). Four T26E3s were also seen in action during the “mad dash” to the bridge at Remagen, providing support, but not crossing the fragile bridge for days. Instead, these heavyweights crossed the Rhine on barges.

After the war, M26s were grouped into the 1st Infantry Division, stationed in Europe as a reserve, following the events of the summer of 1947. The “Big Red One” counted 123 M26s in three regimental and one divisional tank battalions. In the summer of 1951, with the NATO reinforcement program, three more infantry divisions were stationed in West Germany, and accepted mostly battle-proven M26s retired from Korea. However, by 1952-53, these were phased out gradually in favor of the M47 Patton.

The Belgian Army inherited the bulk of these, including many reconditioned M26A1s from USA, for a total of 423 Pershings, leased for free as part of the Mutual Defence Assistance Program. These served in three Régiments de Guides, three Régiments de Lanciers and three Batallions de Chars Lourds. These were also phased out and replaced by the M47 Patton, only two units retaining them by 1961. They were retired from service in 1969. By 1952-53, France and Italy also benefited from the same program and were given M26s. France swapped them soon after for M47s, while Italy retained them operationally until 1963.

Belgian M26 at the Brussels Army museum

The Pacific

While the heavy fighting at Okinawa raised concerns about the losses taken by M4s, it was eventually decided to send a shipment of 12 M26s, departing on May, 31. They landed at Naha beach on the 4th of August. However, they arrived too late as the island was nearly secured.

Korea

The bulk of the M26 (and M26A1) force saw action during the Korean war, from 1950 to 1953. The first units to be called were the four infantry division stationed in Japan, only counting a few M24 Chaffees and howitzer support models. The M24s were quickly found no match for the numerous T-34/85s fielded then by the North Koreans. However, three M26s were found in storage at the Tokyo US Army ordnance depot, and were quickly brought back in service with fortune-made fanbelts. They were formed into a provisional tank platoon by Lieutnant Samuel Fowler. They were deployed in mid-July, first seeing action when defending Chinju. However, their engines overheated and died out in the process. By the end of July 1950, more divisions were sent, but still counting mostly medium tanks, M4s of the latest types. Many M26s were hastily reconditioned and shipped. By the end of the year, some 305 Pershings managed to arrive in Korea.

M26 Pershing in Korea, 1952

After November 1950, however, most of the tank to tank battles were already spent, and North Korean T-34s became rarer. A 1954 survey showed that the M4A3s scored the highest kills (50% because of their large availability), followed by the Pershing (32%) and the M46 (only 10%). However, the kill/loss ratio was clearly favorable to the second and especially for the third, as the M26 found no difficulty getting through the T-34s armor at any ranges, well helped by the largely available HVAP ammunition, while its armor stood well against the T-34’s 85 mm (3.35 in) gun. In February 1951, Chinese forces deployed considerable numbers of T-34/85s, but these were widely spread between infantry divisions for close support. The same year the M46 Patton, the upgraded version of the M26, gradually replaced the Pershing, as it was found unable to display sufficient mobility on the mountainous terrain of Korea.

Starting a Dynasty: The Patton Series (1947-1960)

Too late for World War Two, but also not mobile enough for Korea, produced in small quantities related to other models from the same time frame, the Pershing seemed to have been a stopgap model, bound for history’s dark corners. However, it technically started a brand new generation of US Cold War tanks, sharing the same revolutionary suspension system, roomy turret and low-profile hull, better known collectively as the “Pattons”. A dynasty which lasted well into the 90s, when the last modernized M60s in service came to retirement. Many are still found in frontline units all around the world.

M26 Links & Resources

The M26 Pershing on Wikipedia
The M26 on WWIIVehicles

M26 Pershing Specifications

Dimensions (L-w-H) 28’4” x 11’6” x 9’1.5”
8.64 x 3.51 x 2.78 m
Total weight, battle ready 46 tons (47.7 long tonnes)
Crew 5 (commander, driver, assistant driver, loader)
Propulsion Ford GAF 8 cyl. gasoline, 450-500 hp (340-370 kW)
Maximum speed 22 mph (35 km/h) on road
Suspensions Individual torsion arms with bumper springs and shock absorbers
Range 160 km (100 mi)
Armament 90 mm (2.95 in) gun M3, 70 rounds
cal.50 M2Hb (12.7 mm), 550 rounds
2xcal.30 (7.62 mm) M1919A4, 5000 rounds
Armor Glacis front 100 mm (3.94 in), sides 75 mm (2.95 in), turret 76 mm (3 in)
Production (all combined) 2212

Light Tank M3A3 with 7.5cm PaK 40

Yugoslavian Partisans (1945-49)
Modified Light Tank – 3 converted

Genesis of the Light Tank M3A3 With 7.5 cm PaK 40

The Axis invasion (codenamed ‘Directive 25’) of the Kingdom of Yugoslavia started on the 6th of April 1941 (also known as the ‘April War’). The Yugoslav Army was taken completely by surprise by the speed and size of the Axis forces. The war ended on the 17th of April 1941 with the capitulation, occupation, and division of Yugoslav territory by the Axis forces.

However, very soon after the Axis occupation, in the second half of 1941, the first resistance groups started a rebellion against the occupiers. There were two resistance fighters groups, the Royalist Chetniks (Četnici/Четници) and the communist Partisans (Партизани). The Chetniks were led by General Draža Mihailović (Дража Михаиловић) and the communist Partisans movement was led by Josif Broz Tito (Јосиф Броз Тито). The term ‘Partisan’ describes both groups by definition, but today the name Partisans has become a synonym for the communist resistance movement in Yugoslavia.

Although in the beginning, these two groups worked together in the fight against the occupying Axis forces, a conflict between these two forces in late 1941 would break out into an open civil war. This lasted until the end of the war and the victory of the Partisans.

By the end of 1943 and early 1944, because of the lack of Chetnik actions against the Germans, the Allies decided to send large amounts of military aid to the Partisan movement instead, including weapons, tanks, and aircraft. According to the agreement between the Partisans and the Allies, it was planned to form one tank brigade equipped with Allied fighting vehicles (armored cars and tanks).

A column of Partisan M3A3s. A PaK armed one can be seen just behind the leading vehicle. 

This unit, named the First Tank Brigade, was formed on the 16th of July 1944. The British provided all the equipment needed to equip this brigade. In its inventory, there were some 56 M3A1/A3 Stuart tanks, 24 AEC Mk.II armored cars, and two M3A1 armored reconnaissance cars. The next larger delivery of 36 mostly M3A1 tanks would take place on the 6th of March 1945 (plus a few Stuart tanks received during the war from the Allies) so that the total numbers of Stuart tanks used is around 100.

The caliber (37mm) of the main gun on the Stuart M3A1/A3 tanks was inadequate for anti-tank duties in 1944/45, but Stuarts were still used, since most German tanks on this front were older (mostly Italian and French models). There was also nothing better available at that time, partly because there were not enough Soviet-supplied weapons. The Partisans, as a result, were forced to use the AEC Mk.II armored car (due to its better firepower, the 6 pounder – 57mm Anti-Tank Gun) for engaging better and stronger enemy tanks in mix units together with Stuart tanks.

But this tactic of using both vehicles types for fighting enemy armor led to a lack of any reconnaissance (vehicle or infantry) element of the brigade. The inability to determine exact information about the enemy forces, in particular, unit strength and exact positions, led to great losses.

By the end of the War, more than 60 Stuart tanks were destroyed or damaged. On several of these damaged tanks, the turrets were removed and Partisan engineers decided to try to mount some captured German weapons, to be used as improvised self-propelled guns with increased firepower. Two confirmed modifications are known; one armed with a German 7.5cm PaK 40 anti-tank gun and the second armed with the 20mm Flak 38 Flakvierling anti-aircraft gun. These modifications were quickly built and put into use without proper testing.

There is also no information about the exact names for these vehicles, or whether the Partisans even assigned an official name for them.

Front view of the modified tank. This one is armed with a second Browning machinegun placed above the gun shield or behind it.

The Modifications

On some damaged tanks, the tank turret was removed and in its place, a new modified gun platform was fitted. The upper structure mounted the 7.5cm PaK 40 anti-tank gun with its twin layer gun shield of 4mm (0.16 in.) thick steel and a small armor plate (there is no information on its thickness) between the gun and the tank hull. Two more armored plates were used for the side protection (taken from damaged German Sd.Kfz.251 or 250 half-tracks). In principle, the armor of the upper modified gun platform offered only limited protection for its crew, mostly from small caliber bullets and shrapnel.

The main armament, as previously noted, was the 7.5cm Pak 40 anti-tank. The choice for the main gun was very simple one, as the Partisans captured a number of these guns, so they used what they had. The exact number of rounds for the main gun is not known, but it is often mentioned as being around 25 rounds. The 7.5cm Pak 40 gun had enough power to destroy nearly all types of enemy tanks that could be encountered on this front. These being the German Panzer IV or some captured Russian T-34/76 (known as “Panthers” by the Partisans) in Germans use.

The secondary armament consisted of one original hull mounted Browning 7.62mm (.30 cal) machinegun. On some photographs, a second Browning machine gun can be seen placed on top of the gun shield or behind it, but the photographs are not clear enough.

Due to the removal of the tank turret and installation of the new 7.5cm PaK 40 anti-tank gun, it was necessary to do some modifications on the two roof hatch doors (used by the driver and hull machine gunner) so that they could be opened forwards only. Except for the change in the upper structure of the tank, the rest of the vehicle was the same as the original (hull, running gear, armor, and engine).

The dimensions of this vehicle were similar to the original tank configuration. Due to the length of the 7.5cm Pak 40 gun, it was certainly a bit longer than the original but the exact details are unknown. The weight of this vehicle was probably around some 15 to 17 tons. It had four crew members: commander, driver, gunner, and a loader. The gun crew had a very limited working space to effectively operate the main weapon.

In Combat

There is little information on the precise participation and loses of the Partisan Stuart PaK version. What is known from the contemporary photographic evidence is that they were used in combat. There are only a few documented actions in which these tanks were used.

The PaK armed M3A3 in action somewhere in Yugoslavia. Exact date and location unknown.

They were used at the end of March 1945 in the area of Drenovača (Дреновача) against German positions. Then, on the 27th and 28th of April 1945, near Ilirska Bistrica (Илирска Бистрица), after some heavy fighting (between the Partisan and German forces), the Germans managed to push the Partisans out of Bistrice. This was with the support of one armored company equipped with several or more ‘Panther’ tanks (in reality captured and reused Russian T-34/76 tanks), The next day, Partisans carried out a counter-attack and on that occasion, one T-34/76 was hit and destroyed by a Stuart PaK version. They also took part in tough battles for the liberation of the Trieste (Трст) by the end of April 1945.

The final fate of Pak version is not known, whether they were lost in combat or if they survived. Тhe First Tank Brigade war losses were as previously noted, around 30 to 34 tanks destroyed and a similar number of damaged tanks. So it’s possible that in these numbers include some Pak-conversion tanks.

The role of this vehicle was very likely primarily for destroying enemy heavy armor and as a long-range fire support in a way similar to some German armored vehicles. We can conclude that this hybrid vehicle had both good and bad sides. The positive side was the superior firepower compared to the original and weaker cannon 37mm main gun. Negative sides were: limited working space for the gun crew, weak armor, limited ammunition storage, unproven designed and the whole new gun platform was very likely to stressful for the whole chassis.

PaK armed M3A3 and crew.

Number Built

It is believed three Stuart tanks were modified, but according to other sources (mostly on different internet websites) up to 5 vehicles were rebuilt this way, but this is probably not correct. What is particularly strange is that this conversion always appears alone in contemporary photographs, so it possible that only a single vehicle conversion was ever carried out. Currently, it cannot be exactly verified how many such vehicles were built. Their final fate after the war is unknown.

The 7.5 cm PaK 40 Anti-Tank Gun

The 7.5cm PaK 40 was a Rheinmetall solution for the German problems with their insufficiently strong anti-tank guns. It was first issued in very limited numbers by the end 1941 and start of 1942. It became the standard and a highly effective German anti-tank gun used until the end of the war, with some 20,000 examples being built.

The Pak 40 was in essence just a larger version of the 5 cm Pak 38. It had a split tubular trail carriage, double plate shield (two 4mm plates 25mm apart) to protect the crew, solid rubber tires with a torsion-bar suspension, and a muzzle-brake on the long gun barrel. It was an excellent anti-tank gun, but the main problem with it (according to many sources) was the heavyweight in action, many were lost because they became bogged down in mud, especially on the East Front. After the war, many European countries put them to good use to re-equip their shattered armies for some time.

The maximum effective range of Armor Piercing (AP) rounds was 2 km and for High Explosive (HE) rounds was 7.6 km (4.72 miles). Elevation was -5° to +22° with 65° traverse. Weight in action: 1425 kg /3142 lb. The armor penetration at a range of 1 km (0.62 miles), depending on the ammunition used was around 97 mm which was enough to destroy almost every tank of the period at that range.

The Pak 40 used several different types of ammunition:
– 7.5cm Pzgr Patr 39: Conventional piercing shell (AP) with ballistic and penetrating caps. Complete round weight of 12 kg (26.46 lb),
– 7.5cm Sprg Patr 34: Standard high explosive shell (HE) Complete round weight of 9.15 kg (20.18 lb),
– 7.5cm Patr H1/B: Complete round weight of 8 kg (17.64 lb), Hollow charge shell used in limited number because the low muzzle velocity (450 mps/1476 fps) made precise and accurate shooting at fast targets very difficult.

Specifications

Dimensions 4.33 x 2.47 x 2.29 m
14.2×8.1×7.51 ft
Total weight, battle ready 15-17 tons
Crew 5 (Gunner, two loaders, driver and commander).
Propulsion Continental 7 cylinder petrol
250 hp – air cooled
Speed 58 km/h (36 mph) road
29 km/h (18 mph) off-road
Range 120 km at medium speed (74.5 mi)
Armament 7.5cm Pak 40 Anti-Tank Gun
Armor From 13 to 51 mm (0.52-2 in)

Links, Resources & Further Reading

Artillery From WWI to the present day, Michael E. Haskew, Amber Books 2010.
Waffentechnik im Zweiten Weltkrieg, Alexander Ludeke.
Fighting men of WWII Axis Forces, David Miler, Chartwell Books.
German Artillery of World War Two, Ian V.Hogg
Oklopne jedinice na Jugoslovenskom ratištu, Bojan B. Dumitrijević i Dragan Savić, Institut za savremenu istoriju, Beograd 2011.
Armored units and vehicles in Croatia during WW II, Part I Allied armored vehicles, Dinko Predoević, Rijeka 2002.
Modernizacija i intervencija, Jugoslovenske oklopne jedinice 1945-2006, Institut za savremenu istoriju, Beograd 2010.
http://www.srpskioklop.paluba.info/m3/opis.htm

Olifant Mk1B Main Battle Tank

South Africa (1991)
Main Battle Tank – 44 Built

“Olifant” The African Sledge Hammer Mk1B

The Olifant Mk1B Main Battle Tank (MBT) takes its Afrikaans name from the African Elephant. The Olifant is the largest land animal and in a similar vein the Olifant MBT is the heaviest military vehicle in the then South African Defence Force (SADF) and its successor the South African National Defence Force (SANDF). The Olifant Mk1B is a complete rebuild of the Olifant Mk1A, adapted for the African battle space and the lessons learned from the South African Border War (1966-1989). It was designed and produced at a time when South Africa was still subject to international embargoes because of its racial segregation policies (Apartheid). Set against the backdrop of the Cold War in Southern Africa which saw a steep rise in liberation movements backed by Eastern Bloc communist countries such as Cuba and the Soviet Union.


Olifant Mk1B left hand view- SA Armour Museum, Tempe Military Base (Photo: Dewald Venter)

Development

Unlike the Olifant Mk1A, which is an upgrade from the Centurion Mk.3/5 hull, the Olifant Mk1B was a complete rebuild and in doing so left behind the legacy, features and outer look of the Centurion MBT. Development of the Olifant Mk1B commenced soon after the Olifant Mk1 went into production in 1981. The Olifant Manufacturing Company (OMC) set out to design and build an interim MBT that would improve on the shortcomings of the Olifant Mk1A which were exposed during the South African Border War such as poor armor, poor mobility, improved firepower and taxing maintenance requirements. The Olifant Mk1B was designed to face off against T-55, T-62, and T-72A MBTs, which are equipped respectively with 100mm, 115mm and 125mm main guns. The primary focus, therefore, was placed on protection followed by improved firepower capabilities, then mobility, and lastly reduction of vehicle maintenance and crew fatigue.

A total of 44 Olifant Mk1B (2 x prototype + 42) would be built starting in 1991. South Africa is the sole user of the Olifant Mk1B of which 26 were upgraded to Mk2 standard in 2005. Presently 12 Olifant Mk1Bs are in storage with 1 South African Tank Regiment.

Olifant Mk1B front view- SA Armour Museum, Tempe Military Base (Photo: Dewald Venter)

Design features

The design, development and production of the Olifant Mk1B were undertaken due to the increasing number of Soviet-supplied tanks in Southern Africa. It was particularly feared that the Soviet-backed Cuban forces in Angola would ship T-72A MBTs to the Angolan theatre. The possible deployment of T-72A MBTs necessitated a much better protected, mobile and lethal South African MBT than the Olifant Mk1A.

Mobility

Although the African battle space favors a wheeled configuration, the Olifant Mk1B was envisaged to retain its predecessor’s role as an MBT. The Olifant Mk1B can ford 1.2m of water without preparation. With regards to the mobility question, the Olifant Mk1B kept the Continental 29 liter turbo-charged V12 diesel engine of the Olifant Mk1A. Improvements to the engine enabled an additional 100hp which totaled 850hp and raised the horsepower per tonne from 13.39hp/t to 14.4hp/t. A necessary improvement considering that the Olifant Mk1B weighed 3 tons more than the Mk1A. A new automatic transmission called AMTRA 3 was assembled by Gear Ration and installed in the Olifant Mk1B which provided double-differential steering (four forward gears and two reverse), two-speed mechanical steering drive and hydraulic retarder. The additional 100hp and new automatic transmission allowed the Olifant Mk1B to achieve a top speed of 58km/h (36mp/h) on a road which was a further improvement over the Olifant Mk1A’s 45km/h (28mp/h).

The old Centurion Horstmann suspension was replaced with a new torsion bar suspension system with hydraulic dampers which provides an overall 300-400% improvement in wheel travel if compared to the Olifant Mk1A. Bump stops where fitted to all the road wheels in order to improve off-road mobility while telescopic dampers were fitted to the front and two back stations to reduce rocking when stopping the tank.  Steering is done via a yoke instead of tillers. The overall result of the improvements is a less taxing driving experience for driver and crew, especially over rough terrain.

Continental 29 litre turbo-charged air-cooled V12 diesel engine, SA Armour Museum (Photo: Dewald Venter)

Endurance and Logistics

The fuel capacity remained the same as the Olifant Mk1A, 1240 litres (328 US gallons). Subsequently, the Olifant Mk1B can travel 350km (217mi) on road, 240km (149mi) off-road and 150km (93mi) on sand. With the redesigning of the hull, the engine compartment was extended, allowing more space for easier maintenance and if required, removal and replacement of the entire power pack. In an effort to reduce the frequency of road wheel replacements an outer polyurethane surface was applied which increased the road wheel life from 300km (of the Mk1A) to 1200km on the Mk1B. With the extended engine compartment which lengthened the overall hull, an additional track link was added which brought the total to 109 track links on each side.

The Olifant Mk1B is equipped with one 7.62mm coaxial machine gun with a 2000 round ready bin that replaced the 200 round boxes used in the Olifant Mk1A. At least 6000 rounds of 7.62mm are carried. The Olifant Mk1B features tactical radio communication which allows for reliable command and control, enhancing the tank’s force multiplier effect on the battlefield.

Based on the lessons learned during the South African Border War with the Olifant Mk1A, the Olifant Mk1B features two drinking water tanks (one left and one right) inside the turret with a combined capacity of 101 litres. The water can be accessed from the commander’s and loader’s station and reduces the necessity to leave the tank to fetch water. Less logistical tasks reduced the need for replenishment from an administration and logistic support vehicles from the echelon.  The addition of a fume extractor fan helps clear the interior crew compartment of excess fumes from the main gun. New and more comfortable seats were also installed to help reduce crew fatigue.

Vehicle Layout

The Olifant Mk1B carried a standard complement of four crew members, consisting of the commander, gunner, loader, and driver. The commander’s station is located on the right side of the turret and features a newly designed cupola also offering a 360-degree field of vision through six vision blocks. Entry and exit from the commander’s station are achieved through a hatch. On the right side of the turret, just below the commander`s station is the gunner’s station which is fitted with a day and night sight and to the left of the turret is the loader’s station. The loader also sports a periscope for better overall situational awareness. Entry and exit for the former and latter are through the gunner’s and commander’s cupola and in case of emergency, the loader can escape through a hatch of his own. The driver’s station received a more ergonomic overhaul and a new digital instrument panel and a yoke-type steering stick which improved comfort and reduced driver fatigue. Driver visibility was improved with the addition of a third driver’s periscope thereby increasing situational awareness. The central periscope can be replaced with a passive night driving periscope allowing full day/night capability. The driver can enter and exit his station through a new single-piece hatch or in emergencies escape hatch in the floor.

Interior view of Olifant Mk1B gunners station. Source: SALUT MAGAZINE.

Main Gun

The Olifant Mk1B retained the South African produced 105mm GT3B rifled gun barrel manufactured by Lyttleton Engineering Works (LEW). A new thermal sleeve and fume extractor help improved sustained accuracy when firing and reduce barrel droop due to heat by as much as 70%-90%. The M456 High Explosive Antitank (HEAT) rounds could effectively penetrate 420mm of Rolled Homogenous Armour (RHA) at any range. Armour Piercing Fin-stabilised Discarding Sabot (APFSDS) rounds with the ability to penetrate 580mm of RHA is also used. All the main gun rounds were imported with the exception of the High Explosive (HE) round which is manufactured by Denel in South Africa. The Denel M9210 HE round contains a TNT/HNS filling with an effective blast radius of 17m. The round is fired with a muzzle velocity of 700m/s to a maximum range of 9km. Dispersion at 3 km is within 0.3m x 0.3m.

The fighting compartment saw safety improvements with a total of 65 main gun rounds carried in protected stowage bins below the turret ring. The turret bustle was extended which added more room for crew equipment. The bustle extension also helped balance the overall turret weight distribution, putting much less strain on the new solid state electrical gun control system and turret drive which could traverse the turret in a full circle in 16 seconds (an improvement of 10 seconds over the Olifant Mk1A). An infrared/white searchlight was added above the main gun.

Fire Control System

In 1990 the SADF tasked Reutech Systems to develop a new fire control system to replace the 30-year-old system on the Olifant Mk1A. The fire control system was known as the High Frequency Tank Fire Directing System (HIFF) and consisted of a state of the art (for the time) ballistic computer system and sight drive electronics coupled to a touch button control system and sensors which accurately measured meteorological conditions such as ambient temperature and wind speed from the environmental sensors which could affect the fire accuracy of the main gun. The new system allowed the gunner to select a target and in less than two seconds the fire control system would calculate a fire solution and notify the gunner via a ready to fire light that the main gun was on target and ready to fire.  The system could also hit a moving target while on the move itself by adjusting the main guns aim after incorporating the targets distance, speed and relative speed thereby maximising first round hit probability. The gunner makes use of an Eloptro 8x gunner’s day sight with an integrated ballistic computer which was added to the gunner’s sight. Co-mounted is a laser range finder which is accurate up to 10km. Data from the rangefinder is fed into the split range drum, which applies elevation to the main gun. Tests revealed that the system is accurate within 50m x 50 m at 2 km which is perfect for the South African Lowveld (open stretches of grass plains).

Protection

Having established that the Olifant Mk1A is vulnerable to Soviet T-55, T-62 and T-72A MBT`s, an upgrade of the Mk1B’s armor was undertaken. The Mk1B retained the original Olifant Mk1A’s armor, which consisted of 118mm (4.64in) on the frontal glacis at 60 degrees, 152mm frontal turret (6in), 51mm (2in) on the sides, 40mm (1.57in) on top and 19mm (0.7in) in the rear. An armor upgrade installation program took the form of several passive composite armor packages over the frontal glacis plate and turret (front, sides and top). A gap in between the original Olifant Mk1A turret and the add-on turret package was left open to act as spaced armor against High Explosive Anti-Tank (HEAT) rounds or which could be filled if needed in future. The total thickness of the armor package upgrade and the composition thereof is classified, however, given the threat level posed it would be reasonable to argue that they would be sufficient to deal with 115mm HEAT rounds used by Soviet T-62 tanks. Being modular the add-on armor package can be replaced in the field if it is damaged.

The entire hull could shrug off the feared 23mm anti-aircraft gunfire. Furthermore, the threat posed to the Olifant Mk1A by Rocket Propelled Grenades such as the RPG-7 is negated with the mentioned upgrades to the Mk1B. The armored steel skirts of the Olifant Mk1A redesigned allowing for easier removal while still providing additional protection against RPG-7s. The constant threat of landmines in Southern Africa necessitated the addition of a double armored floor (with the torsion bars between the floor plates). A new fire suppression system (automatic & manual) was installed in the crew and engine compartment to reduce the likelihood of a catastrophic fire or explosion if hit. The stowage bins received lids to reduce the chances of content ignition if the Olifant Mk1A’s is hit. The smoke grenade banks were prone to damage when “bundu bashing” (driving through dense vegetation) which encouraged the relocation thereof to the rear of the turret on the Olifant Mk1B.

Two banks of four smoke grenade launchers were fitted. Additionally, the Olifant Mk1B can also generate a smoke screen by injecting fuel into the engine exhaust. The hull headlamps are armored and a V-shape bush basher bar could be added to the nose of the hull. The total additional weight adds up to just over 3 tons.


Olifant Mk1B rear bustle view- SA Armour Museum, Tempe Military Base (Photo: Dewald Venter)

VARIANTS

Olifant Bridge Laying Tank

Two Olifant Mk1B Bridge Laying Tank (BLT) were built which are employed by the SANDF engineering corps.

Tank Technology Demonstrator and Olifant Mk1B Optimum
The Olifant Mk1B was developed as a stop gap while the SADF were looking to acquire a brand new MBT. The Logim project was aimed at researching, developing and manufacturing a complete domestic MBT. The project reached the prototype phase with one working model build known as the Tank Technology Demonstrator (TTD) which looked very similar to the Leopard 2A4. The technology developed for the TTD would eventually be transferred to the Olifant Mk1B Optimum in addition to a new lighter turret made of advanced ceramics with a reminiscent shape found on the Leopard 2A6. Additionally, the Olifant Mk1B Optimum would feature rubber side plates to detonate medium HEAT rounds and at the same time, save weight. After the fall of the Soviet Union and the 1994 democratic elections, the new SANDF had a significantly reduced budget. Hence the TTD and Optimum projects were canceled. Most of the technologies would eventually be transferred to the Olifant Mk2.

Olifant Mk1B Optimum – SA Armour Museum, Tempe Military Base (Photo: Dewald Venter)

Conclusion

The Olifant Mk1B was, for all practical purposes, a leap forward in protection, mobility and firepower over its predecessor, the Olifant Mk1A. However, several problems came to light, such as the poor power to weight ratio and the failure of the main gun system to exceed the performance of the Mk1A. Additionally, the desired fight ability improvement was not achieved. These shortcomings motivated the SANDF to look for further improvements which led to the Olifant Mk2 which made use of many of the TTD technologies.

Olifant Mk1B Specifications

Dimensions (hull) (l-w-h): 8.30m (26.3ft.)– 3.43m (10.8ft.)– 3.04m (9.64ft.)
Total weight, battle ready 59 Tons
Crew 4
Propulsion Continental 29 litre turbo-charged air-cooled V12 diesel engine produces 850 hp @2400rpm. (14.4 hp/t)
Suspension Torsion bar
Top speed road / off-road 58 kph (36 mph) / 30 kph (18.6 mph)
Range road/ off-road >350km (217 miles) / 240km (149 miles)
Armament (see notes) 105mm GT3B semi-automatic quick firing gun (L7)
1 × 7.62mm co-axial Browning MG
Armour 118mm (4.64in.) glacis @ 60 degrees + add-on armour package
152mm (6in.) turret + add-on ceramic armour package
51mm (2in.) sides
40mm (1.57in.) top
31mm (1.22in.) rear
Total Production (Hulls) 44

Olifant Videos

Olifant Mk1A and Mk1B Demonstration

Tank Technology Demonstrator

Bibliography

Carroll, S. 2017. Olifant Mk1B. Date 2-4 Oct. SA Armour Museum, Bloemfontein.
Erasmus, R. 2017. Olifant Mk1B. Date 2-4 Oct. SA Armour Museum, Bloemfontein.
Erasmus, R. 2017. Olifant Mk1B. Date 21 Nov. Telephone interview with Olifant Mk1B project leader.
Harmse, K. 2017. Olifant Mk1B. Date 16 Nov. Vaal Mall, Vanderbijlpark.
Global security group. 2015. Olifant Mk1B. https://www.globalsecurity.org/military/world/rsa/olifant-1b.htm Date of access: 16 Sep. 2017.
SALUT Magazine. 1996. Advance technology. October Edition.
SADF living history group.  2015. Armour. http://sadfgroup.org/equipment/armour/ Date of access: 16 Sep. 2017. Steenkamp, W. & Heitman, H.R.  2016.  Mobility Conquers: The story of 61 mechanised battalion group 1978-2005.  West Midlands: Helion & Company Limited
VEG Magazine. 2005. The development of the Olifant Mk1B & Mk2. Issue 8. Victor Logistics.

FV4005 Stage I & II

United Kingdom (1950-56)
Anti-tank SPG Prototype – 2 built

In the early 1950s, the opening years of the Cold War, the western powers were highly concerned with the amount of powerful armor available to the USSR.

In answer to this, the British military developed a ferocious new anti-tank gun, the 183 mm (7.2 in) L4. The race was on to find a suitable mount for this monstrous weapon. It was first proposed to be used as part of the FV215 project. This self-propelled gun (SPG) design was based on the FV200 Universal tank concept. This vehicle, however, did not go further than the mock-up stage.

FV 214 Conqueror

Designers tried again, this time with a proposal to mount the gun on the chassis of Britain’s trusty new Main Battle Tank, the Centurion. This vehicle would go under the project title of FV4005.

Design and Development

The FV4005 was a separate project from the Centurion based vehicle, the FV4004 Conway, armed with the 120 mm (4.72 in) L1 gun. The two projects were not related but had the same goals. The FV4005 was fitted with a much larger gun.

Vickers-Armstrong was in charge of the development of the tank. The Centurion chassis chosen for the project was that of the Mk.III. The platform for the gun was made to fit perfectly into the existing turret ring of the hull. Only slight alterations were made to the chassis. A large recoil spade was added to the rear of the vehicle and an equally large travel lock, or “Gun-Crutch” as the British called it, was added to the front.

The recoil spade helped to keep the vehicle in place while firing, meaning the gunner didn’t have to re-adjust after every shot. The travel lock was used to keep the gun from swaying while the vehicle was moving, helping to reduce stress on its components.

Britain’s Biggest Boom-Stick, the 183mm L4

In 1950, work started on the Ordnance Quick Firing 183 mm (7.2 in) L4 gun. At the time, it was the largest and most powerful tank gun in the world. The cannon was based on the 183 mm (7.2 in) BL 7.2 inch howitzer, a WWI era weapon. The gun itself weighed a mighty 4 tons and when fired it produced the equivalent of 87 tons of recoil force.

The L4 was designed to be chambered for only one type of ammunition, HESH (High Explosive Squashed Head). It was separately loading ammunition. The projectile was loaded first followed by the correct propulsion cartridge. Each shell weighed a combined total of 104.8 kg (231 lbs). A shell of this size understandably produced a substantial amount of fumes and smoke inside of the fighting compartment. As such, a large fume extractor was added to the barrel, a relatively new feature at the time.

The 183 mm was tested in live fire trials against a Centurion and a Conqueror. In 2 shots, the 183 blew the turret clean off the Centurion and split the mantlet of the Conqueror in half. In total, the gun fired 150 shells.

Stage I

The FV4005 Stage I was a relatively simplistic vehicle, serving as little more than a test-bed for the 183 mm L4 gun. The hull of a Mk.III Centurion tank was chosen for the project. The gun was mounted on a platform in the turret ring, completely open to the elements devoid of any armor.


The Stage I, possibly in Workshop 5 (the so-called secret shed at Elswick) – Photo: warspot.ru

The L4 was expected to have a rate of fire of 6 rounds per minute. As mentioned above, the separately loading 183mm HESH ammunition equipped to the FV4005 weighed a combined total of 104.8 kg (231 lbs) each. As such, the gun would require 2 loaders to service the weapon effectively. 6 rounds a minute would still be a hopeless fantasy, however.

To combat this, in an attempt to ease and quicken the loading process, Vickers-Armstrongs developed a mechanized ammunition feed system, similar to that used on the 104-mm Green Mace anti-aircraft gun. Contrary to popular belief, this was not a traditional auto-loader. It was simply a loading assistance device that would help to align the shells and propellant with the breach. The mechanism did not include a rammer.*

Testing highlighted stability issues with the platform when the gun was fired. It was also surmised that the open, unarmored fighting compartment, necessitated by the loading-system, was not worth the price in crew safety. As such, work began on re-working the gun platform.

 

Stage II

The FV4005 Stage II was the final form of the project. It was designed and built in 1955. The open gun platform was replaced with a large, box-like turret. The loading assistance device was also deleted, in favor of more traditional loading. With the addition of the large, approximately 2-meter high turret, the FV4005 weight climbed to 50 tons.


The FV4005 during trials in 1956. Note the driver in the hull, and the commander at the very top of the turret. Photo: warspot.ru

Despite being an extremely prominent target, the turret armor was only 14 mm (0.55 in) at its thickest. This was easily penetrable even by large caliber machine guns rounds. It also only had enough space to store 12 rounds. These rounds were stored in racks of 6 on each side of the large bustle.

The turret housed 4 crew members. These were the commander on the forward left, gunner on the front right and 2 loaders positioned behind the gun. On the left of the gun, in a small box on the cheek, was a coaxial .30 cal (7.62 mm) machine gun. This was most likely used for ranging rather offensive/defensive fire. There was a large door in the rear of the turret bustle for crew access and ammunition re-supply. The driver was located in the standard position in the hull.

It should be noted that the lack of armor was intentional. This vehicle was designed to engage at long-range, shoot and re-position. Flexibility was slightly hampered by the turret, however. In theory, it was fully traversable. On uneven ground, this was not recommended due to balancing issues with the gun. As such, the vehicle only really had a 90 degrees arc of fire to the left and right.

A rear view of the vehicle. Note the recoil spade and the box above it. This box holds the winch to raise and lower the spade – Photo: Ed Francis

Fate

January 1957 marked the end of the road for the 183 mm armed SPGs, despite admirable performance during trials. The intended role of the vehicles had been overtaken by increasing development of ATGMs (Anti-Tank Guided Missiles). These granted the same, if not better, anti-armor capabilities, with the experiments ultimately culminating in the Malkara and Orange William missile systems.

Work would continue on the gun. Had it have been adopted, the L4 would’ve been succeeded by the 180mm “Lily White”. This only got as far as conceptual stages, however.

The FV4005 Stage II is the only one of these 183mm armed vehicles to survive to this day. The turret is original, but it was mounted on a spare Mk.VIII Centurion hull, not the original it was trialed with. It is missing the recoil spade and travel lock. This “Cut-and-Shunt” representation of the vehicle now sits as a “gate-guardian” at The Tank Museum, Bovington, alongside an M4 Sherman. Its predecessor, the FV4004 Conway is safe and sound in the VCC (Vehicle Conservation Center) at the site.

The 4005 as it stands today out side the Bovington Tank Museum – Photo: warspot.ru

FV4005 Stage II Specifications

Dimensions (L-W-H) 7.82 (without gun) x 3.39  x 3.6 m
(25’7″ x 11’1″ x 11’8”)
Total weight 50 tons
Crew 5 (driver, gunner, commander, x2 loaders)
Propulsion Rolls-Royce Meteor; 5-speed Merrit-Brown Z51R Mk. F gearbox 650 hp (480 kW), later BL 60, 695 bhp
Speed (road) Apx. 30 km/h (19 mph)
Armament QF 183 mm (7.2 in) L4 Tank Gun
.30 Cal. (7.62 mm) machine gun.
Armor 120 mm frontal hull armor. Turret 14mm all over.

Links, Resources & Further Reading

Ed Francis
Archives, The Tank Museum, Bovington, England
Key Publishing Ltd., The Big Gun Centurions, Classic Military Vehicles. Written by David Fletcher.
An article on the FV4005 by Yuri Pasholok on warspot.ru (Russian)

ELVO Leonidas

Greece (1982)
APC – 900+ built

About ELVO company

The state-owned company, Elliniki Viomihania Ohimaton (“Hellenic Vehicle Industry”) was founded in Thessaloniki in 1972 to produce locally Steyr-Daimler-Puch models after an agreement with the Austrian company. It was known originally as Steyr Hellas S.A. and manufactured motorbikes and farm tractors before focusing in the 1980s on military vehicles. A license to produce the 4K 7FA was secured and the vehicle was to be known locally as the “Leonidas” after the Spartan king. When the first production was achieved, followed by exports, the company was renamed ELVO in 1986, embarking on the all-improved Leonidas II.

Leonidas 2 APC

The latter was much more a local product than the first. In 1988, development started with Steyr for a new IFV -which development was pursued with Spain to give birth to the Pizarro/Uhlan instead. The company indeed left the development, which was resumed in 1998 with a local IFV, the Kentaurus, revealed but not followed by any order. The company also produced 140 Leopard 2 HEL MBTs under a KMW license but accumulated losses. The company should have been dissolved in 2015 but this was frozen by the state.

Design of the Leonidas I

The first two prototypes were ordered from Austria in 1981. Few modifications were made to the 100 vehicles to follow, which were initially to be built locally, but gradually locally-manufactured parts found their way into the manufacturing process.

Largely based on the Saurer 4K 7FA, already largely treated, the first Leonidas did show some detailed modifications like the exhaust vents and left muffler, the shape of the hatch, hull fasteners and handbars, even the main gun-shield with a set of smoke grenade dischargers behind the gunner’s seat. The basic version was an APC with a prismatic hull and a drivetrain comprising six roadwheels, front idlers (where the engine was) and rear idlers.

Leonidas 2 APCs

Suspensions were torsion bar units with shock absorbers on the first and last roadwheels units. The all-welded hull made of steel RHA is prismatic, with a front engine compartment and transmission (STEYR 7FA, inline 6-cylinder water-cooled diesel, producing 320 hp at 2,300 rpm.). The driver was located behind to the right-hand side, followed by the gunner/commander in its open turret, a shielded cal.50 12.7mm M2HB heavy machine gun. Behind was located the troop compartment, without pistol ports but with roof hatches and rear doors. The Leonidas 1 was produced from 1982 to 1983.

Development of the Leonidas II

In 1986 the Leonidas 2 was developed as an improved version with added Greek components. 56 were manufactured, 40 by Greece and 16 by Austria, all purchased by Cyprus. In 1987 the Greek government ordered 344 of this version, all manufactured in Greece. it met the final selection, meeting the Army’s operational needs in March 1987 and was designed as an Infantry Fighting Vehicle (IFV).

This version had a new turret, weighed 18.8 tons (4 ton heavier), was propelled by a 450 hp (instead of 320 hp) engine coupled with a ZF 6 HP 500 automatic transmission (instead of the ZF 6-S80 manual transmission with 6 gears forward and 1 reverse), and its top speed was 70 kph (instead of 63 kph). The first phase of the program cost 22 billion drachmas and it was also stated its price was 8.5% lower than the Leonidas 1 mostly built from Austrian parts.

The turret ring was made compatible with a large array of weapons systems, like A 20-30 mm autocannon turret, a 90 to 105 mm Cockerill cannon turret (at the rear), or 81-120 mm mortar. In practice, the turret was unarmed or received the same cal.50 as in the Leonidas 1. This turret was partly enclosed and the smoke dischargers were located on each side. The other modifications were additional automatic fire suppression system, commander’s rotating periscope and better smoke grenade dischargers, but overall a more powerful engine and better performances.

Leonidas 2 IFV – rear view

Fate

Production was maintained in 1993-95 (141) for Cyprus and a last Greek batch of 57 vehicles in 1998, and ten more for Macedonia (FYROM) in 2001 with a new automatic transmission. The general total figure given is around 900 vehicles, of which 503 were in service with the Greek Army (most active today), and 197 for Cyprus. The Austrian proposal for a joint development in 1998 was eventually rejected (Elvo built the Kentaurus instead) but also a Leonidas 3, as it was argued the type was already obsolete.

Video: Short documentary about ELVO

Links

The Leonidas 2 on wikipedia
The Leonidas on Globalsecurity
On Army-guide.com
Additional photos-greekmilitary.net

Leonidas 2 Specifications

Dimensions 5.87 x2.50 x1.70 m (19.3 x8.2 x5.7 ft)
Total weight, battle ready 18.8 tons
Crew 10 (driver, cdr/gunner, 8 infantry)
Propulsion 6-cyl Steyr 430 hp
Suspension Torsion bars
Speed (road) 70 km/h (xx mph)
Range 520 km (320 mi)
Armament 12.7 mm M2HB, 7.62 mm MG3, See notes
Armor 26-32 mm (0.24-0.35 in)
Total production 900 in 1982-2001

Conqueror FV214

United Kingdom (1954)
Heavy Tank – Around 180 built total

From the “Universal Tank”

The postwar “Universal Tank” concept was derived from the 1944 A45 Infantry Support Tank concept, an attempt to create, right after the Centurion, a successor heavy tank to the Churchill. However both projects were fused as the FV200 universal tank series that was to have the mobility of a cruiser but the level of protection and firepower of a heavy tank as well as a versatile chassis for other purposes (ARV, SPG…). The heavy tank variant Fv201 (55 tonnes, 20-pounder gun) was chosen for development to respond to the Soviet IS-3. It was to be armed with a 120 mm, however the delay to create such massive gun and the turret led to the transitional F221 Caernarvon, fitted with the Centurion Mk.2 turret. Eventually, the definitive FV214 was built in 1955 in two series; and deliveries lasted until 1959.

Design

Protection

The Conqueror was the last British Heavy Tank in service. It was largely a product of WW2 thinking about tanks, and unlike first generation MBTs, put the typical emphasis on firepower and protection over mobility. They were tailored to defeat the Soviet IS-3 when the cold war was at its hottest and would have been surely up to the job (see later). The hull made of RHA was all-welded and relatively low, with a well-sloped glacias nose and cast turret design. The armor level was particularly high, with 178 mm nominal thickness front plates (7 inches), but equivalent to 250 mm (10 inches) LOS (line of sight). The lower beak was 78 mm at 60°, the rear part of the front glacias, connected to the turret ring, 21 mm at 83°, and rear engine deck 17 mm, the rear plate 51 mm (flat), the rear lower plate 31 mm at 70° and the bottom, 13 mm. The upper and lower side walls were 51 mm thick, flat, and the protective side skirts 6 mm.

Conqueror Armour scheme

The cast armor turret had a similar front thickness and even superior on the mantlet (200 mm). The front was 150-170 mm thick, the front slope was 44 mm at 78°, the roof 31 mm, the rear 31 mm, and the rounded sides walls 89 mm. The general profile of the tank stayed relatively low, slightly higher than the IS-3.

Mobility

The hull and chassis of the FV 200 series were designed for a wide variety of duties, and sturdy enough for the heaviest loads. It was composed of a typical “heavy tank” drivetrain, in two 8×2 roadwheels groups per side, for 64 roadwheels in total, resting on double pin, large track links to reduce ground pressure. Reinforced and sturdy Horstmann units instead of torsion bars assumed the suspension. The paradox was only light tanks and the heaviest in service in the UK were given these, like, until the Chieftain in the 1960s. By the 1980s, the Challenger adopted hydropneumatic units. Based on coil springs bogies, they had a relatively long course, were 100% external and easy to replace and maintain, while the torsion bars were partly internal.

Conqueror Mk. I at Bovington

All this armor made it for an exceptionally heavy tank, at 64 tons compared to the Centurion’s 51. The only source of power available was the proven Rolls Royce Meteor, in a souped-up version of the WW2 Cromwell and Centurion 650 hp, coupled with a 5-speed Merrit-Brown Z51R Mk. F gearbox. Its top speed and range were consequently severely limited, and the stress both on the engine, transmission (only 800 hp), and suspensions took its toll, making it mechanically unreliable. Tactical mobility in addition was limited by the few bridges capable to handle it weight. However the small roadwheels resting on many bogies and wide tracks had the effect of giving similar traction and mobility performances as the Churchill, if not better. It could climb and go in some places the centurion couldn’t, despite the latter was 13 tons lighter.

Armament

The IS-3 main gun indeed was ill-designed for accurate long-range fire, fast rate of fire or was limited in its ammunition capacity due to old-fashioned two-stage rounds. On the contrary, the British Royal Ordnance L1 120 mm rifled gun was tailor-made and much more capable gun than the IS-3 at long range. In fact, all studies shown that it was capable to out-range the IS-3 by a generous margin. That, in theory, would have rendered heavy armor unnecessary, but experience showed that engagements rarely occurred in optimal distances and terrains. The secondary armament comprised two cal.30 Browning machine guns, one coaxial and the second placed on the roof, manned by the tank commander.

Conqueror Mk. I rotatable Tank Commander Cupola at Bovington

It should be noticed that the commander had an advanced rotating cupola, providing an equally advanced fire control system as he could align it on a target independently of the turret, to measure the range with a coincidence rangefinder. He could then direct the gunner on the laying and azimuth parameters which were mechanically indicated in the cupola. This was a very early “hunter-killer” mode allowing to rapidly engage several targets. At the same time, the Soviet TPKU-2 and TKN-3 did not use a rangefinder.

Conqueror Mk.I on trials in 1956

Evolution

FV214 Conqueror Mk I This first version (20 built) had three periscopes for the driver.
FV214 Conqueror Mk II This second, more produced version (160) had redesigned frontal armour plates joins but a single rotatable periscope for the driver, and a modified, improved exhaust system.
FV215: A semi-SPG design with a FV200 chassis mounting a limited traverse turret armed with a 183 mm gun. Only a wooden mockup was produced.

FV221 Caernarvon

The FV221 Caernarvon

Considered as a stopgap tank before the heavy turret was ready, it was nonetheless part of the FV 200 lineage. At the end, the Centurion was found better. Only the Caernarvon mobility was judged satisfactory, as its turret was far lighter and its engine at least on paper (800 hp vs 650 hp) much more capable. But in terms of speed and range, it lagged behind. They were given the Mk III 20 pounder turret of the Centurion mark II but never really hit their mark as main battle tank and after a single prototype Mark I, only a short experimental serie (21) Mark II was released.

Conqueror ARV2 FV 222\

FV222 Conqueror ARV

This was the heavy Armoured Recovery Vehicle (ARV), still used years after the retirement of the main type. One is still on active duty as a training beach recovery vehicle today. To the Mk I (8 produced) succeeded the Mk II, with 20 produced. Devoid of a turret and with a tailor-made superstructure, it weighted 57 tons had a winch capacity of 45 tons in direct pull. The design of the glacis slope was different, much less pronounced. Towing crane and apparatus were stored on the side of the rear deck. Steel cables were attached to the side skirts.

In Action

All the 180 Conqueror ever built were stationed in Germany, in the northern British sector, facing the possible Soviet onslaught. Their rôle was also to provide a long-range cover for the early, 20-pdr armed Centurions. They would have been also directed against Soviet heavy tanks units, on par with the American M103s. They stayed in service in Germany only seven years, nine given to each tank regiment, and usually grouped in three tank troops. They Participated in rare exercises (due to their poor tactical mobility). In the early 1960s, the arrival of the Centurion armed with ROF’s L7 gun made the last British heavy tank obsolete and they were retired.

Surviving vehicles could be found at the Bovington Tank Museum, and the Land Warfare Hall of the Imperial War Museum Duxford. Another is on display in France, at the Musée des Blindés, Belgium at the Royal Museum of the Army (Brussels) and Kubinka in Russia. The American Littlefield Collection also counts one. In Germany, several training target hulks could be seen at the Haltern Training area. ARVs also survived, two at the Military History Museum on the Isle of Wight, and the REME Museum of Technology. Another ARV is in service at the Amphibious Experimental Establishment AXE (Instow, North Devon) for beach tank recovery practise.

Sources/Links about the Chieftain

The Conqueror on Wikipedia
Conqueror and various concepts on Henk of Holland

Video: Duxford Tankfest 17/06/2012

Conqueror Specifications

Dimensions 38oa/25.4 x 13.1 x 10.5 ft (12 x 3.99 x 3.19 m)
Total weight, battle ready 64 tons short (128,000 ibs)
Crew 4 (Driver, commander, gunner, loader)
Propulsion Rolls-Royce Meteor M120 810 hp (604 kW) – pwr 12 hp/t
Suspension Hortsmann suspensions
Speed (road) 22 mph (35 kph)
Range 100 mi (164 km)
Armament Main : ROF L1 4.7 in (120 mm)Sec. coaxial + roof Browning 0.3 in (7.62 mm)
Armor 7 in (180 mm) front glacis+turret (250 mm LOS)
Total production 185 in 1959.