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

Vickers Medium Mk. III

United Kingdom (1930)
Medium Tank – 3 Built

By the early 1920’s, the British Government’s enthusiasm for a state tank program had collapsed following the unsuccessful ‘Medium Mark D’. This project had eaten up the majority of the Government Tank Design Bureau’s budget and the widely overambitious model had been horribly unreliable. The exit of Winston Churchill from the Ministry of Munitions in 1921 was a key turning point in the downfall of publicly owned tank design in the United Kingdom. Military spending was falling as the troubled post First World War UK economy improved little in the 20’s and colonial duties bit away at what money there was, while the defense sector was slipping back into a conservative and skeptical stance. Within two years, the funding stopped coming and the nation that had invented the tank now left tank development to the private corporations.

Fortunately, the Vickers Company (that would become Vickers Armstrong in 1927) had begun competing with the Government over a contract for a replacement tank for the infantry in 1920. At the time the Mark D fell through in 1923, several prototypes of what would become the Mark I Medium had already been produced. The Mark I and Mark II vehicles produced throughout the 1920’s were indeed substantial improvements over the World War 1 era vehicles still in service. They replaced the last MK. V Heavies and Whippets as the 1920’s closed, being the only tanks mass produced in this period anywhere in the world, with a total run of just under 300 vehicles.

The previous Mk. II model on the left with the Mk. III on the right. Photo: Tank Archives Blogspot

These tanks incorporated a rotating turret and were more mobile that preceding tanks. While now it may seem trivial, this represented a leap in design with the three-man turret. This took the workload off the commander and main gunner (who in most vehicles of other tank building nations during the Interwar period were the same person) and would likely have had a serious positive influence in combat.

Despite these relative innovations, the vehicles had serious flaws. Some were quickly recognized others were not. Already in 1926, requests for an improved vehicle came from the War Office. The Mk.I’s and II’s had proved difficult to drive, and their top speed of only 15 mph (24kph), while meeting the requirement for a tank that was designed to primarily operate alongside infantry, still left something to be desired. While they were not mechanically as gremlin ridden as First World War vehicles, a number of improvements were suggested to make a more reliable vehicle. What may also have been more apparent to some military staff was that the mere 6mm of armor protecting these vehicles, which was less even than the Mk.

I Heavies of 1916, would struggle to deflect even small arms fire at close range. More than twice this thickness was needed for a vehicle to reliably protect against even standard issue infantry weapons at close range. By September 1926, Vickers, requirements in hand, went to work.

Initial Design, the A6

A weight limit of 15.5 tons was set for the new vehicles, so that they could be supported by the standard British Army pontoon bridge of the day. Easy rail transport, space for a wireless radio set, and (relatively) quiet running mostly for the benefit of crew wellbeing were also essentials. Later, easier steering ability and better protection were also requested. The initial design submitted by Vickers Armstrong was named the A6, and based loosely on the A1E1 Independent, which was still in testing at the time. One fad that this monstrosity briefly inspired was that of the multi-turreted tank. The A6 design featured the same QF 3-pounder gun as the Mark I and II, but it was housed in a two-man turret, accompanied by three secondary machine-gun turrets. One was at the rear with an anti-aircraft machine gun mount and two at the front of the vehicle with two machine guns in each, although later this was reduced to one in each. The A6 had 13mm of armor at the front and 7mm elsewhere. This kept the weight down to around 14 tons and it was estimated a 180hp Armstrong engine would propel the vehicle at 20 mph (32kph) on road.

In 1927, after the wooden mock-up was approved, the prototype was ordered, fitted with a new hydraulic ’Wilson Epicyclic’ steering gearbox. The three prototypes that were produced were fitted with the Armstrong V8 engines which exceeded expectations, and gave the vehicle a top speed of 26 mph, positively rapid for an interwar vehicle. Unsurprisingly, the machine gun arrangement was not well received on trials in 1928, and the vehicle was not judged to be far enough superior to the Mark II to warrant a serious production order.

The Revised Mark III

Determined to salvage the project, Vickers Armstrong ordered an improved vehicle in 1928, with two being built at the Woolwich Royal Ordnance Factory and another at Vickers. These featured slightly better armor, 14mm at the front and 9mm around, as well as a new turret capable of housing a radio set. The rear machine gun turret was abandoned, while the other two were shifted forwards to improve weight distribution. Better brakes were also fitted. From 1930 to 1933, further trials were far more positive. The vehicle was deemed more reliable, offered greater crew comfort and provided a more stable platform for the 3 pounder gun that the Mark I and II. Additionally, the top speed had further improved to a highly respectable 30 mph (48kph).

For all their work, the suspension proved somewhat overladen and the track components fast wearing out when used off-road. Finally, the 3 finished vehicles were purchased for use by the Royal Tank Corps and in 1933, entered service as HQ tanks. However, the high cost of the eight-year project more than outweighed its technical improvements, and no further orders were made. By the mid-30’s, British tank doctrine was moving on, and the Medium tank had no place in it. A Soviet purchasing commission came to look at British vehicles for export in 1930 and purchased a number of British tankettes and light tanks. At the same time, it appeared that, through the use of some skulduggery, they obtained fairly detailed information on the A1E1 prototype and Vickers Mark III. After an investigation, a British Officer was court-martialed in 1933 for selling the plans on. It is sometimes claimed that the Mark III provided some design inspiration for the T-28 Medium Tank, of which more than 500 were produced and fought in the Winter War and opening stages of Barbarossa.

The Mk. III on the left with the similar A1E1 Independent on the right. Note that they both share the void in the sides designed for the placement of a stretcher to evacuate wounded crew. Photo: IWM

Brief Service

The last vehicle of the batch, ‘Medium III E3’, was used as a command vehicle for one of the largest combined arms training exercises of the era. On Salisbury Plain in 1934, this vehicle was used alongside other experimental armored and mechanized forces in the British Army, to test their potential and help find their role within the army in future conflicts.

A factory-fresh Mk. III. Photo: IWM

Ironically, the exercise this vehicle was used in would hurt British tank progress in the short term. The results were skewed by conservative officers who played down the role of the tanks in the exercise, an example of the disruption British tank design in the 1930’s faced. Some historians in the postwar era such as that of author and expert David Fletcher have gone so far as to suggest that these traditionalists, who were resistant to new practices in the army, used their positions to prevent the implementation of new tactics and equipment. They are accused of a ‘Great Tank Scandal’ which put Britain on the back foot of tank design as it entered World War Two.

The one silver lining for the participating Mark III, however, was that it was crewed by Brigadier General Percy Hobart, later ‘Sir’ Percy Hobart. He was an armor development expert who takes credit for designing some of the specialised tanks used for the D-Day landings that began the liberation of France in 1944. Perhaps some of his inspiration came from the ponderous tank he commanded around the training field on its only active duty in 1934. Shortly after the exercise, the participating vehicle was written off, another was destroyed in a fire, and the sole survivor remained in service around the training ground until 1938, and was likely scrapped some time within the next two years. Hence, sadly, none of the vehicles have survived to this day.

On the training ground towards the end of its service in 1938. Photo: Tank Archives Blogspot

Specifications

Dimensions 6.55 x 2.67 x 2.79 (21.4 x 8.75 x 9.15 ft)
Total weight, battle ready 16 long tons
Crew 6
Propulsion Armstrong Siddeley V8 180bhp
Speed 30mph (48 kph)
Range 120 Miles (190 Km)
Armament QF 3 pdr (47 mm/1.85 in)
3 x 0.303 Vickers machine guns (7.7 mm)
Armor 14 to 9 mm (0.55 to 0.35in)
Total production 3 (+6 A6 Prototypes)

Links, Resources & Further Reading

HMSO Publishing, The Great Tank Scandal: Part 1: British Armour in the Second World War, David Fletcher
Southwater Publishing, World War I and II Tanks, George Forty
Tank Archives Blogspot
Landships.info
The Imperial War Museum

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

Sherman Crocodile

USA/Great Britain (1943)
Flamethrower Tank – 4 built

 

Although they had proved extremely useful in America’s fight against the Japanese in the Pacific, Auxiliary Flamethrowers (a flamethrower that is secondary to the main gun, rather than replacing the gun) were quite unpopular with the US Army fighting in the European Theatre of Operations (ETO).

Despite this, the British Churchill Crocodile, with its iconic trailer and bow mounted flamethrower, was well admired. American troops, who had received invaluable support from them, placed great faith in these British dragons. While the Churchill Crocodile was still being tested, American interest grew in the project, resulting in the development of their own version.

The American version would be based on their venerable workhorse, the Medium Tank M4 Sherman. It would become known as the Sherman Crocodile, in line with its Churchill brother.

The single M4A2 based Sherman Crocodile. Photo: Panzerserra Bunker

Development

In March 1943, US officers were shown the prototype of the Churchill Crocodile and queried the possibility of creating a similar vehicle based on their own Medium Tank M4, known to the British as the Sherman. In a meeting between UK, US, and Canadian military heads held on the 29th of June, 1943, at Dumbarton Oaks, Maryland, USA, it was surmised that the British led the Americans in flamethrower technology. This ‘flamethrower conference’ was held to evaluate possible requirements for future operations in Europe, namely Operation: Overlord, the amphibious landings of Normandy, which were planned for the following year.

The US Army informed the British War Office (WO) on the 11th of August, 1943, that they were estimating a need for around 100 of these ‘Sherman Crocodiles’, as they would come to be called. Construction of a wooden mock-up of the vehicle was completed by the British Petroleum Warfare Department (PWD). This mock-up was then inspected on the 1st of October, 1943. This was followed by a working prototype which was completed in January 1944. Trials took place at the end of that month, with a demonstration held for US officers on the 3rd of February. Overall, these officers would extremely pleased with the tank.


An M4A4 fitted with wooden mockups of the flame equipment. Photo: Panzerserra Bunker

The First US Army put in an order for 65 tanks that month. This number grew to 115 units when it was predicted that General Patton’s Third US Army would also require armored flamethrowers in their future exploits. The initial order for Overlord, submitted to the British War Office on the 16th of February, was for 100 Sherman Crocodiles including 125 of the accompanying armored trailers. The first production vehicle was finally completed in March.

Initially, the Sherman Crocodile was going to a truly large collaboration between British and American industry. The plan was for the American side to provide any parts necessary or unique to the M4 Sherman. The British, who would also construct the Crocodile, would provide the trailer and component parts of the flamethrower. In reality, British factories became overwhelmed with the production of their own Army’s orders for the Churchill Crocodile and were barely scraping together other orders. As a result, no Sherman Crocodiles were ready for the US Army on D-Day.

Design

Foundation, The M4

The M4 started life in 1941 as the T6 and was later serialized as the M4. The tank entered service in 1942. All Sherman Crocodiles were based on the M4A4, with one exception. The single Crocodile prototype was based on the M4A2.

The M4A2, known to the British as the Sherman III, was a diesel-powered model. The radial petrol engine of previous models was replaced with the General Motors 6046 engine (a combination of two GM 6-71 General Motors Diesel engines). The hull was of a welded construction.

The M4A4, known to the British as the Sherman V, was almost exclusively used by the British military and, like the A2, had a welded hull. Many A4s were famously converted into the 17-pounder armed Firefly. The unique feature of the A4 was its Chrysler Multibank engine. This large power plant was unpopular with the American military but liked by the British. This larger engine also resulted in the lengthening of the hull. This is most noticeable when looking at the suspension bogies as the gap between the units is much bigger than other M4 models.

The average speed of the M4 series was 22–30 mph (35–48 km/h). The tank’s weight was supported on a Vertical Volute Spring Suspension (VVSS), with three bogies on each side of the vehicle and two wheels per bogie. The idler wheel was at the rear.

Standard armament for both models consisted of the 75mm Tank Gun M3. This gun had a muzzle velocity of up to 619 m/s (2,031 ft/s) and could punch through 102 mm of armor, depending on the AP (Armor Piercing) shell used. It was a good anti-armor weapon, but it was also used to great effect firing HE (High-Explosive) for infantry support. For secondary armament, the M4s had a coaxial and a bow mounted .30 Cal (7.62 mm) Browning M1919 machine gun, as well as a .50 Cal (12.7 mm) Browning M2 heavy machine gun on a roof-mounted pintle.

Flame Equipment

The M4 base vehicle remained mostly unchanged. It retained full operation of its turret and 75mm gun and bow-mounted .30 Cal (7.62mm) machine gun, as was intended for an auxiliary flamethrower. Depression of the 75mm was slightly hampered over the right of the upper glacis, however, due to the placement of the flame gun.

The basic layout of the Sherman Crocodile was the same as the Churchill. All of the flamethrowing equipment would be external. This included the Crocodile’s iconic wheeled trailer which was attached to the rear of the tank. This coupling at the rear of the vehicle was officially known as “The Link”. The trailer weighed 6.5 tons and was protected by 12mm (0.47 in) thick armor. “The Link” was made up of 3 articulated joints which allowed it to move up, down, left or right and swivel on the horizontal axis to allow it to navigate rough terrain. The trailer carried 400 UK gallons (1818 liters) of flamethrower liquid and 5 compressed bottles of Nitrogen (N₂) gas. The tank could be jettisoned from inside the tank in case of emergency.

Loading of the fuel trailer. The fuel is poured in by hand on the left. The nitrogen gas bottles are loaded into the rear on the right Photo: Osprey Publishing

The Nitrogen gas propelled the fuel along a pipe which ran from the rear plate of the tank, along the right flank, to a flame projector mounted on the upper glacis to the right of the co-driver/bow machine gunner’s position. The entirety of the pipe was covered in thin metal plating to protect it from shrapnel or small arms fire. This flame projector was mounted on a pedestal protecting by sheet metal plating. It had a full range of motion, able to actuate up and down, as well as traverse left and right. The weapon was operated by the bow-gunner/assistant driver with controls at his station.

The flame gun on the front of the Sherman. Photo: Panzerserra Bunker
Sherman Crocodile (M4A4 based) of the 739th Tank Battalion in Julich, Germany, February 1945. This photo shows in excellent detail the flame gun and its armored pedestal. Also note the small frame welded onto the upper glacis to the left of the gun. This is likely a crew improvisation to stop the cannon colliding with the flame gun. Photo: Osprey Publishing

Service

Including the Crocodile prototype built on the M4A2, only four Sherman Crocodiles would be completed out of an initial introductory order of six. The three production models were built on the hulls of the newer M4A4.

The Crocodiles were effectively kept in a state of limbo in the UK until a request came in for Crocodiles in November 1944. This request came from General Omar Bradley’s 12th Army Group and General William Simpson’s 9th US Army. These armies showed the most enthusiasm to armored flamethrowers, having been some of the first to benefit from the support of British Churchill Crocodiles during the fighting in and around the port city of Brest. More Sherman Crocodiles were requested, but production never resumed.

The four Shermans were sent to the 739th Tank Battalion (Special Mine Exploder Unit), a unit that had previously been equipped with Canal Defence Lights (CDLs).

Sherman Crocodiles would have to wait until February 1945 for their first and only use in combat. They took part in Operation: Grenade, the assault on the ancient 13th-century citadel in Julich, Germany. On the 24th of February, the Crocodiles supported the 175th Infantry, 29th Division in their efforts to secure the town. The town was secured by afternoon, but the garrison of the old citadel was putting up a stiff resistance.

Sherman Crocodiles of the 739th in Julich, Germany, 1945. Photo: Osprey Publishing

The embattled fortress was surrounded by a moat that was 85-foot (26 meters) wide and 20-foot (7 meters) deep. Division commanders were not keen on throwing wave after wave of infantry against the walls of the citadel, so the

Crocodiles were brought in. The Crocodile unit arrived at half-strength, due to the fact that two of the tanks broke down before reaching the battle. When the remaining tanks arrived, they advanced to the edge of the moat and began to pump flaming liquid through every possible void. A large number of defenders quickly abandoned their positions and retreated underground.

With the garrison seeking refuge, the Crocodiles turned their attention to the gates of the citadel. The tanks pounded the gates with approximately 20 rounds of High-Explosive from the 75mm main guns. When they had succeeded in blowing the gates off their hinges, the Crocodiles resumed flaming, covering every inch of the inner courtyard in flames.

With the last survivors from the fort running to nearby hills, the 175th Infantry waded across the moat, securing the complex by 15.00 hours (3:00 pm) that day. The Citadel would continue to burn for two days. In March, the Crocodiles would support elements of the 2nd Armored Division after crossing the Rhine, but after this, there was very little need for the Crocodiles once the Siegfried line had been breached and passed.

Sherman Crocodile (M4A4) pulls its trailer through soggy terrain. Also, note the rather unique and rarely seen shroud around the flame gun. Photo: Panzerserra Bunker

Other flamethrowers were used with standard gun Shermans in Europe. These were either the E4-5 or ESR1 Auxiliary Flamethrower that replaced the bow machine gun. They were also in use in the Pacific fighting the Japanese. Though their effect was described as “positively pathetic” by commanders in the ETO, a large number of the weapons were used.

An interesting point to note about the three Crocodiles based on the M4A4 is that these are among some of the only M4s of that iteration to serve with the American Army in the European Theatre. The only other time the A4 was used by American forces in the ETO was after the Battle of the Bulge when US armored forces had a brief shortage of tanks. Gaps were filled with some A4s from British stocks.

The Crocodiles survived the war, but what happened to them is unknown. None of them are known to survive today.

Sherman Crocodile (M4A4) in action. Photo: Presidio Press

Other American M4 Flamethrowers

In the Pacific Ocean Theatre (PTO), the Americans had successfully designed and built a main armament flamethrower on the M4. A main armament flamethrower replaces the main gun, unlike the auxiliary of the Crocodile. This vehicle was known as the M4 POA-CWS H1 (POA-CWS: Pacific Ocean Area-Chemical Warfare Service) and was mostly used on the M4A3 model of Sherman. They served in a number of famous actions, including the assault on the treacherous volcanic island of Iwo Jima.

There was also use of smaller “periscope” flamethrowers that were attached to the co-driver/bow machine gunner’s hatch. This was also designed by POA-CWS, and was designated the H1 Periscope Mount Flame Thrower.

American development of Mechanized Flamethrowers based on the M4 continued after the war, resulting in such projects as the T33, as well as the M42B1 and B3 which served in great effect in the Korean War.

Further British Experiments

Alongside the Crocodile, British designers continued to work on other possible flamethrowing Shermans. Most notably, this took the form of more reptilian Sherman flamethrowers. These were the Salamander series and the Sherman Adder. Both of these were based on the M4A4.

The Salamander series went through 8 variations, Type I to Type VIII. They all focused on finding the best location for the flamethrower and accompanying equipment. The flamethrower of choice for this tank was the Wasp IIA which had a range of 90 – 100 yards (82 – 91 meters). Designed by the Petroleum Warfare Department, the initial Type I mounted the Wasp in an armored sheath under the 75mm main gun and was fed from fuel tanks in the sponsons. Type II and III were designed by the Lagonda luxury car company and they were the only variants to have a smaller crew at four men, instead of the regular five which the other models retained and mounted their flamethrowers in the 75mm gun tube. Type II also tested a flame gun mounted above the co-driver/bow machine gunner’s position. Type IV to VIII were all designed by the PWD. They all varied in pressurization methods and fuel tank arrangements. On Type VI and VIII, the flame gun was mounted in a blister on the side of the turret. On Type VII it was mounted in the antenna socket on the right front of the hull.

Salamander fell by the wayside. Though tested for a short period in 1944, nothing came of the projects. The next project was called the Adder. The configuration of the Adder was thus: an 80 UK gallon (364-liter) fuel tank was mounted on the rear plate of the M4. An armored pipe running across the top of the right sponson fed the fuel from this tank to a flame gun mounted above the co-driver/bow-machine gunner’s position. The gun had a range of 80 – 90 yards (73 – 91 meters). A simple armored skirt was added to the flanks to protect the suspension. Like the Salamander, however, the project did not make it past prototype stages.

Specifications (M4A4 based)

Dimensions (L-W-H, without trailer) 19’4” x 8’8” x 9′ (5.89 x 2.64 x 2.7 m, measurments without trailer)
Total weight, battle ready 37,75 long tons (35.3 tons, 83,224 lbs)
Crew 5 (commander, driver, gunner, loader, flamethrower operator)
Propulsion Multibank/radial petrol engine, 425 hp, 11 hp/ton
Suspension HVSS
Top speed 40 km/h (25 mph)
Range (road) 193 km (120 mi)
Armament 75mm Tank Gun M3
Flamethorower on upper glacis
Roof cal.50 (12.7 mm) Browning M2
Coaxial cal.30 (7.62 mm) Browning M1919
Armor 90 mm (3.54 in) max, turret front
Total production 4
For information about abbreviations check the Lexical Index

 

Links, Resources & Further Reading

Presidio Press, Sherman: A History of the American Medium Tank, R. P. Hunnicutt.
Osprey Publishing, New Vanguard #206: US Flamethrower Tanks of World War II
olive-drab.com
panzerserra.blogspot.co.uk

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

Stridsvagn m/21 & m/21-29

Sweden (1921)
Light Tank – 10 purchased

The German WWI LK II Light Tank

The German Army developed the LK II light tanks near the end of WW1 in order to enable their forces to take advantage of any breakthrough in the Allied line of trenches. They were called Leichte Kampfwagen LK II and had a top speed which was double that of the German Sturmpanzervagen A7V heavy tank or the British Mark V tanks. Unfortunately for the Germans, the war ended before the LK IIs could be used in action. Under the terms of the peace treaty, they had to get rid of them.

In 1918, the Swedish Military attaché in Berlin was shown a British Mark IV heavy tank knocked out by the Germans. He submitted a report which helped start the search for suitable tanks to equip the Swedish Army. The big British tanks were not suitable for the Swedish terrain. Inquiries were made to see if they could purchase the British Whippet Mark A calvary tank but the per tank cost was too high, so an alternative was sought.

German LK I light tank prototype from 1918 armed with a 7.92 mm (0.31 in) machine gun. Maximum road speed 11 mph (18 km/h).

The German cavalry tank LK I, devised in mid-1918 by Joseph Vollmer, was based on a Daimler car chassis and never left the prototype stage. The engine was mounted at the front of the tank with the driving and fighting compartment constructed behind it. It was followed by a more powerful LK II. Initially, the Leichte Kampfwagen LK II was going to be armed with a 57 mm (2.24 in) cannon in the 360° turret and a 7.92 mm (0.31 in) machine gun in the hull. The gun was tested in the turret on 29th August 1918, but it was found to be too powerful and deemed unfit for installation in a light tank. It had a strong destructive effect on the LK II tank’s riveted armored chassis. For this reason, the 57 mm (2.24 in) cannon was rejected and replaced with a smaller 37 mm (1.46 in) Krupp gun. (The Swedish tanks did not have a hull-mounted machine gun. Their m/21 only had a 6.5 mm/0.25 in machine gun in the turret.)

The suspension consisted of multiple small un-sprung roadwheels and the whole running gear was protected by armored skirts, with integrated mud chutes. Like the original, the armor thickness ranged from 4 mm to 14 mm (0.16-0.55 in), but assembly was by riveting.

Although two prototypes were finished in June 1918 and a series of 580 was ordered, the war ended before any became operational. Only 10 were built by the end of the war. Later, by virtue of the Versailles treaty, Germany was forbidden from developing tanks in any form.

Swedish Strv m/21 tank No.10 crossing a bridge whilst on exercise.

The First Swedish Tank m/21

Sweden purchased their first tanks from Germany in 1921. They were ten LK II light tanks for the cost of 200,000 Swedish Kronor. Under the articles of the Versailles Peace Treaty Germany was forbidden from owning any tanks. In the autumn of 1921, they were shipped to Sweden in secrecy, described as agricultural tractor parts and sheet metal boiler plates.

The tanks were re-assembled at the Naval shipyards in Stockholm. A royal letter dated in August 1922 records the granting of funding for the establishment of the Svea Livgarde (Swedish Life Guards) Panzervagnarna armored vehicle unit in Stockholm.

The interior of a Swedish m/21 tank

At first, the newly arrived LK II German tanks were given the name Pansarvagn försöksmodell/1922. It was then changed to Swedish Army designation fm/22. The letter ‘f’ signified that the vehicle was under test and the number 22 represented the year of the tests 1922. This was later changed to Stridsvagn m/21 (Strv m/21). The letter ‘m’ indicated that the vehicle was now operational and the number 21, 1921 the year it was reconstructed in Sweden.

In August 1922, the Swedish armored unit of the Lifeguards started military trials with their new tanks. They even had the use of one French Renault FT tank, but it was in such a bad condition that it was eventually used as an artillery target. The Strv m/21 tanks were at first painted army gray on the inside and out.

Camouflage paint schemes were added later. White wash was painted over the main body during the snowy conditions of winter. The engine was started using a hand crank but if near the enemy the engine could be started from within the safety of the armored fighting compartment.

Stridsvagn m/21 on exercises in Sweden

When the tanks were first reassembled in 1922, they were placed in storage after a few basic mechanical tests. It was not until August 1923 that they saw their first major test under battlefield conditions. Five Strv m/21 tanks were transported across country to Skåne, where they took part in a large military exercise in support of an infantry attack. They performed well.

The m/21 tanks were regularly used in military exercises between 1923 and 1927. Through constant use, some of the tanks suffered mechanical breakdowns. The big problem for the Swedish Army was that there were no German factories producing spare parts. This was illegal under the peace treaty. The Swedish Army mechanics started to strip parts from five of the tanks so that they could have five tanks available for action.

This situation continued until 1927, when a company was eventually found that could produce the necessary spare parts. Part of the solution was to change the engine and transmission fitted in the tank from a German one to a Swedish engine.

Swedish Stridsvagen m/21 tank painted in winter camouflage livery

The Stridsvagn m/21-29 Upgrade

Five of the ten tanks received an upgrade. They easiest way to identify a m/21 from a m/21-29 is to look at the front of the tank. The new m/21-29 was fitted with headlights in the front of the tank, which had armor plates covers that could be swung into place.

To ease maintenance problems, they were equipped with a new Swedish Scannia-Vabis 1544 85 hp engine, a new exhaust system and gearbox. It now weighed 9.7 tons and had a maximum road speed of 18 km/h (2 km faster than the original m/21). It was originally armed with a 6.5 mm (0.25 in) machine gun. This was replaced with a 37 mm (1.46 in) Škoda infantry gun L/27.

Its armor piercing AP shells weighed 0.825 kg, had a muzzle velocity of 460 m/s and could penetrate 22 mm (0.87 in) of vertical armor at 500 m (550 yd). The high explosive HE shells weighed 0.825 kg. The position of the exhaust was moved to the side of the left door and there was now an electrical starter button for the engine inside the tank.

These five vehicles were designated m/21-29. They were not all upgraded at the same time. Two were completed in 1930 and the other three received their upgrade between 1931 and 1934.

There are three of these upgraded vehicles remaining. One was shipped to the German Tank Museum in Munster in 1938 and is still on public display. The Arsenalen Tank Museum in Sweden owns two Strv m/21-29 tanks and is in the process of restoring them to a working condition. They also have an original Strv m/21.

The Strv m/21 and Strv m/21-29 were withdrawn from the Swedish Army service in 1938, when they were replaced by the Czech CKD AH-IV tankettewhich was given the name Swedish Strv m/37.

You can identify a upgraded Swedish m/21-29 tank from the original m/21 by the addition of covered headlights.

Gallery

A 1920s photo of a Strv m/21-29
Stridsvagen m/21 tank No.10 of the Svea Livgarde (Swedish Life Guards) Panzervagnarna armoured vehicle unit.
Rear view of the crew hatch on the Stridsvagn m/21 whilst on exercise in Sweden.
Early photograph of a Swedish Stridsvagen m/21 tank painted grey. It was No.9. Notice the original exhaust pipe position.
Notice the repositioned exhaust silencer on this upgraded m/21-29 Swedish light tank.

Surviving Tanks

The only 1918 original Swedish m/21 LKII tank can be found at the Arsenalen Tank Museum near Stockholm, Sweden.
Side view of a preserved Swedish m/21-29 tank at the Arsenalen Tank Museum near Stockholm, Sweden.
Swedish Army 1918 German built LK II light tank Stridsvagn m/21-29 at the Deutsches Panzermuseum, Munster, Germany.

Sources

The Stridsvagn m/21 on Tank-Hunter.com
The Stridsvagn m/21-29 on Wikipedia

Strv m/21 Specifications

Dimensions (L-w-h) 5.70 x 2.05 x 2.52 m (19 ft x 6.7 ft x 8.3 ft)
Total weight, battle ready 9.7 short tons (19,400 lbs)
Crew 2 (commander/gunner, driver)
Propulsion Daimler-Benz 1910 in-line 4-cylinder gasoline, 55 hp
m/21 Top speed 16 km/h (10 mph)
m/21-29 Top speed 18 km/h (11 mph)
m/21 Armament Ksp m/14 6.5 mm (0.26 in) light machine-gun
m/21-29 Armament 37 mm (1.46 in) Škoda Infantry gun L/27
Armor From 4 to 14 mm (0.16-0.55 in)
Purchased 10

AS-90 Artillery SPG

United Kingdom (1990)
Self Propelled Howitzer – 179 built

Development of the AS-90

AS-90 is an abbreviation for Artillery System for the 1990s. The official name is “Gun Equipment, 155 mm L131”. It is a self-propelled artillery gun developed for the British Army. The program started as a replacement for the 105 mm FV433 Abbot SPG and the M109 155 mm Self Propelled Gun. It was started as a private venture by Vickers because they believed the SP-70 SPG tri-country development program would fail. They were correct.

 

The minister of defense indeed issues a specification when the project eventually was canceled, and among four propositions, Vickers Shipbuilding and Engineering (VSEL) AS-90 design was chosen and approved. The latter became BAE Systems in 1999 and production started in 1992, until 1994. By 2006 there were plans to upgrade the 155 mm howitzer, for better range and accuracy, and

AS90 at the Larkhill Artillery Range

start closing on naval needs for a joint program. The whole program was evaluated to £300 million ($480 million USD) in 1995.

Design of the AS-90

Armament

The basic design around the new 155 mm SPG came from a 1963 Ballistics Memorandum of Understanding for a 39 caliber ordnance of this caliber, with a baseline projectile standardized to the US M549 rocket-assisted shell. The Vickers howitzer was found compliant to this standard, using the L15 unassisted projectile which allows a range of 24.7 km, but with some specifics.

Instead of the more common screw breach, a split sliding block breech with Crossley obturation system was chosen. This allowed the use of bagged charges instead of metal cartridges. The primer magazine contained 18 primers and the standard ammunition was the FH-70 round (L15 HE) while the cheaper M107 is used in training instead. The main gun is capped by a double-baffle muzzle brake.

The howitzer range was 24.9 km (39 cal), and 30 km with the tested 52 cal version and standard charges. The rate of fire was 3 rounds in a 10 seconds burst saturation fire, 6 rounds per minute for 3 minutes or 2 rounds per minute in sustained fire. The secondary armament comprised a 7.62 mm L7 GPMG on the roof. The ammunition comprised 48 projectiles and charges, with 31 stored in the turret and 17 located in the hull and 1000 MG rounds.

AS-90 training in Salisbury plains

Energy

The gun had its own power supply independent of the main engine in order to fire in a stationary position while keeping the battery charged for any move. The Elevation, traverse, magazine, shell transfer, loader motion are electrically-powered as well as the electronics and communications.

Hull, Turret & Propulsion

The hull was custom-built to support and propel the fully traversing turret. It was made of welded RHA, 17 mm thick on the front glacis, NATO-proven against small arms fire, 14.5 mm armor piercing shells and 152 mm shell fragments. The turret itself had sloped sides, and was approximatively 2/3 of the whole length of the hull. Added to the gun, the overall length was 9.07 m.

The crew comprised the driver (center front) with its own day/night periscope, while the commander, gunner and loaders were housed inside the turret. There was a rear door for access/exit of the crew and ammunition supply.

The drivetrain comprises six paired roadwheels (rubber-clad) suspended by hydropneumatic (Hydrogas) arms (Horstman Defence Systems), with the drive sprocket on front and idler at the rear. The powerplant is a Cummins 90 degree, v8, 4 stroke, liquid cooled, turbo diesel VTA903T capable of 660 bhp. This diesel developed a power-to-weight ratio 14.66 hp/t.

It is coupled with a ZF Gears Ltd automatic transmission with four forward and two reverse gears. Max Speed was around 54-55 km/h on flat, and range 370 km (231 miles). Ground clearance was 41 cm and on trials, the AS-90 showed it could negotiate gradients of 60°, a vertical obstacle of 75 cm, cross 110 inches wide trenches and fording a 1.50 m deep water strait.

Electronics

The main gun uses an autonomous navigation and gun laying dynamic reference unit (DRU), applied directly on the trunnion. A common Turret Control Computer (TCC) compiled data from the various sensors on the roof and gun muzzle, received data from the HQ and human inputs. The Detachment Commander, loader and layer (Avimo direct fire sight) had their own display & command displays by VSEL.

The autolaying is provided by the combined data from the DRU, TCC and powered laying controls. A Radar Muzzle Velocity Measuring Device helps fire in reversionary mode via the direct fire sight. The automatic gun-laying system (AGLS) serving elevation and traverse laying is credited for a 1 mile accuracy (angle 3.375 minutes), and rapid target engagement. There is also a barrel cooling system to help achieve faster rates of fire.

AS-90 firing in Basra, March 2003

Evolution

In 1999, Vickers was integrated into BAE systems and it was asked an upgrade program for a 52 cal. main gun upgrade to increase the range. Marconi Electronic Systems tested a bi-modular charge system developed by Somchem of South Africa, but due to several issues, notably the failure to meet the intensive fire requirements, the whole project was terminated.

The 96 out the 179 vehicles electronic systems were upgraded along the capability enhancement program of 2008-2009. Part of it comprised the laser inertial artillery pointing system (LINAPS) digital gun sight.

Variants

The AS-90D is a special version modified for desert use with an extra climatization for the crew, and extra cooling for the engine and gun machinery. The design of the tracks is adapted for sandy conditions, lessening the sand wear on metal, which runs on a Diehl 940-single pin track.

The Haubicoarmata “Krab” – is a Polish license built AS-90 turret married with a K9 Thunder chassis (Huta Stalowa Wola and WB Electronics). It received the “Azalia” BMS. Two prototypes were built in 2001, and successfully completed all required evaluations trials. Initial serial production started in 2008, with eight units delivered to Polish Land Forces for testing. In 2014 production of Krab chassis was forwarded to Korean Samsung Techwin, which will build 120 units, replacing Polish built UPG chassis.

Haubicoarmata Krab

In Action

The 179 AS-90s were given to three British field regiments supporting armoured infantry brigades: 1st Regiment Royal Horse Artillery; 19th Regiment Royal Artillery and 26th Regiment Royal Artillery. Their rapid-fire capability allows them to deliver a total payload of 261 kg onto a single target in less than ten seconds, coming close of the German Panzerhaubitze performances.

The AS-90 took part in several joint exercises, including in the Arizona Desert in 1994, in Kuwait and Saudi Arabia in 1996.

In 29 March 2001, a unit was deployed during Operation Cambrai in Kosovo. This unit was used to fire illumination rounds, enabling British troops to spot any suspected Albanian rebels trying to cross the border, in support to the KFOR deployment.

In March 2003, AS-90Ds were deployed in Iraq during Operation Iraqi Freedom. They saw action around Basra and following the deployment of British troops in the area.

However in July 2004, the UK Ministry of Defence announced a reduction of six vehicles per battery.

The most recent joint exercises Raytheon M982 Excalibur extended-range 155 mm trials took part in 2006. The AS-90 proved compatible with the M982 Excalibur Ia-2 rounds.

Sources

The AS-90 on Wikipedia
AS-90 on Army-technology.com

AS-90 Specifications

Dimensions 9.07 oa x 3.50 x 2.49 m (29.9 x 11.6 x 8.2 ft)
Total weight, battle ready 45 tons ( ibs)
Crew 5 (Driver, commander, gunner, loader, layer)
Propulsion Cummins VTA903T V8 diesel 660 hp (493 kW) – pwr 14,6 hp/t
Suspension Independent hydro-pneumatic torsion bars units
Speed (road) 53 kph (33 mph)
Range 420 mi (261 km)
Armament Main : BAE systems 155 mm L31 39 cal. 48 rds howitzerSec. 7.62 mm GPMG NATO L7
Armor 17 mm front (0.66 in)
Total production 179 in 1992-95.

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

76.2mm GMC M18 Hellcat

USA (1944)
Tank Hunter- about 2,507 built

Historical Background

As the United States army entered World War II, it drew certain conclusions from Germany’s quick victories over Poland and France. One was that a highly mobile tank destroyer force needed to be held in reserve to deal with sudden Panzer breakthroughs as they occurred, rather than keep anti-tank forces at the front.

Therefore, anti-tank elements were removed from infantry divisions to form independent battalions, which were initially equipped with a number of improvised mobile tank destroyers, the M3 half-track mounting a 75 mm (2.95 in) gun, and the GMC M6, a truck with a 37 mm (1.46 in) gun.

Restored M18 GMC Hellcat tank destroyer at the Military Odyssey event in southern England.

Once Operation Torch provided battlefield experience for the army to evaluate, it became apparent that more powerful tank destroyers would be needed. First of the more powerful weapons was the M10, built on the chassis of an M4 armed with a 76.2 mm (3 in) gun. However, the M10 was still insufficient, so an order went out for a tank destroyer designed from the ground up to hunt and destroy tanks. This vehicle would become the M18 Hellcat.

In December 1941, the Ordnance Corps issued a requirement for a fast tank destroyer using torsion bar suspension, a Wright/Continental R-975 engine, and a 37 mm (1.46 in) gun. This became the T42 37 mm (1.46 in) Gun Motor Carriage. The army then changed their request to a vehicle mounting a 57 mm (2.24 in) gun, thus the designation changed to the T49 57 mm Gun Motor Carriage. Yet another change, requesting a 75 mm (2.95 in) gun, led to the T67 Gun Motor Carriage, of which one was built from a T49 chassis.

Finally, the T70 76 mm Gun Motor Carriage emerged and would become the M18 Hellcat. It was designed by Harley Earl at Buick. Tests on an oval track, as well as a specially designed bumpy track, demonstrated that the lightly armored vehicle could achieve high speeds. Production of the M18 started on January 7th, 1943, when 1,000 units were ordered.

Design

Speed and agility were the hallmarks of this particular tank destroyer; these qualities came about from using a powerful engine and by keeping armored protection to a minimum. As was the case with other tank destroyers used by the United States, the M18 had an open turret, which left the crew vulnerable to snipers, grenades, and shrapnel.

Rarely was the high speed of the Hellcat fully used in combat, but the ability to outflank German tanks, for side and rear shots, did benefit the crews against the heavily armored Panther and Tiger tanks. Ease of maintenance came from the engine being mounted on steel rollers, which permitted quick removal and replacement. The transmission was also easily accessed in this manner. The 76 mm (3 in) gun soon proved to be not as effective as hoped against German armor, although a limited supply of high-velocity armor piercing ammunition did compensate to some extent.

The crew comprised five members, the commander in the turret left rear, gunner in the turret left front, loader in the turret right, driver in the left front, and assistant driver in the hull right front. The armor consisted of rolled and cast homogeneous steel, as follows: Gun shield .75 inch (1.9 cm) from 0-60 degrees; Front (cast) 1 inch (2.5 cm) 23 degrees; Sides .5 inch (1.3 cm) 20 degrees; Rear .5 inch (1.3 cm) 9 degrees; Top (none); and floor 0.25 in (6 mm).

The main armament was a 76 mm (3 in) M1A1, M1A1C or M1A2 gun with 45 rounds. It had a 360-degree manual and hydraulic traverse at 24 degrees/second, +20 degrees to -10 degrees of elevation/depression. The secondary armament comprised a .50 (12.7 in) caliber M2HB machine gun in a ring mount (800 rounds), rotating 360 degrees, with manual traverse.

Production

In July of 1943, the Hellcat went into production at the Buick plant in Flint Michigan. Although Buick was contracted to build 8,986 Hellcats for the US army and Lend-Lease recipients, only a total of 2,507 vehicles were produced, with production ceasing in October 1944.

Variants

There were a number of variants tested using the chassis of the Hellcat. The T86 and T86E1 amphibious tank destroyers, as well as the T87 105 mm (4.13 in) amphibious Howitzer Motor Carriage, the T88 105 mm (4.13 in) Howitzer Motor Carriage and the Super Hellcat mounting the turret from the M36 turret were all tested, but none proceeded to production before war’s end.

M39 of a Medical unit in Korea

The only variant of the M18 to see production and combat was the T41/M39 armored utility vehicle, used as a turretless personnel or cargo carrier and as a gun tractor. M39s saw service in both World War II and Korea, before being declared obsolete on February 14th, 1957. A prototype of the M39 was tried as a flame thrower tank, the T65. It did not go into production.

Active Service

Although some Hellcats went to China to fight the Japanese army, they were primarily used in support of infantry, as Japanese armor was scarce and of poor quality. Two battalions of tank destroyers did see service in the invasion of the Philippines using Hellcats. Starting with Anzio in Italy, M18s saw action in Italy and Northwest Europe.

Hellcat at Wiesloch, Germany, 04/01/1945.

The following tank battalions used the M18 during part or all of their service: 602nd battalion 9\1944, 603rd 8\1944, 609th 9\1944, 612th 1\1945, 637th 1\1945 (Pacific), 638th 11\1944, 643rd 2-3\1945, 648th 5\1945?, 656th 2\1945, 661st 2\1945, 704th 7\1944, 705th 7\1944, 801st 4\1945, 805th 6\1944, 807th 4\1945, 809th 2\1945-4\1945, 811th 11\1944, 817th 4\1945, 820th 4\1945, 822nd 4\1945, 824th 3\1945, 827th 12\1944. Note: The dates are for when the unit received the Hellcat.

According to the army’s “Seek, Strike, Destroy” doctrine, these battalions were to be kept under the control of upper echelon headquarters, in order to respond quickly to mass Panzer attacks. However, since the Germans almost never employed their tanks in this manner, the battalions ended up parceled out to infantry divisions, where they provided direct fire support, blasting pill boxes and other fortifications, or in indirect fire roles interdicting German movement. Not designed for these roles, the M18 nevertheless did excellent work supplementing the artillery of these infantry divisions.

Throughout the long campaign in Italy, then through France and the Low Countries, the tank destroyer units had a number of moments to shine as tank destroyers; at Arracourt, in France, on September 19th 1944, the 704th TD battalion in support of the 4th Armored Division destroyed 15 tanks of the German 113th Panzer brigade while in a dense fog; during the Ardennes offensive on December 19th-20th 1944, 4 Hellcats of the 705th TD battalion supported an attack on the 2nd Panzer division.

This spoiling attack slowed down the German attempt to seize Bastogne until the Americans could organize their defenses. In addition to serving with the United States army, the Hellcat also served with the armies of Taiwan, West Germany, and Yugoslavia (until the 1990’s).

An article by Tim Cox

Sources & Links about the M18 Hellcat

tankdestroyer.net
AFV Data Base
The Pacific War Online
“Seek, Strike, and Destroy: US Army Tank Destroyer Doctrine in World War II.” Dr. Christopher R. Gabel; Combat Studies Institute, US Army Command and General Staff College Fort Leavenworth Kansas September 1985
Buick M18 Hellcat Tank Destroyer First Drive – Four Wheeler
M18 76mm Gun Motor Carriage Hellcat – History of War
M18 Gun Motor Carriage (Hellcat) – Tank Destroyer/Gun Motor Carriage – History, Specs and Pictures – Military Factory
UNITED STATES ARMY IN WORLD WAR II, The European Theater of Operations – “THE LORRAINE CAMPAIGN” Hugh M. Cole

76mm Gun Motor Carriage M18 Specifications

Dimensions
(L-W-H)
19ft 9″ x 9ft 11in x 7’3″
(6.01m x 3.03m x 2.32m)
Total weight, battle ready 18 tons (39,000 lbs)
Crew 5 (driver, co-driver, commander, gunner, loader)
Propulsion Continental radial R-975-C4 9 cyl., gas. 900T Torqmatic transmission
Top speed 50 mph (80 km/h) road
18 mph (29 km/h) off-road
Range (road) 105/160 mi (160 km at cruising speed)
Armament 76 mm (3 in) gun M1A1/M1A1C/M1A2, 45 rounds
Cal.50 (12.7 mm) Browning M2HB, 800 rounds
Armor From 1 inch (glacis) to 0.2 in (floor) (25 mm to 5 mm)

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.