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

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

Char B1/B1 Bis

 France  (1935-40)
Heavy Tank – 369 built

A Long-lasting Project

The Char de bataille was Col. Estienne’s concept. The French “father of tanks” wrote a memorandum (Mémoire sur les missions des chars blindés en campagne) in 1919, full of war experience, tactical reports and theoretical concepts of mechanized warfare, notably the proper use of different types in the offensive. The “char de bataille” (“battle tank”) was a heavy tank, near to the “char de rupture” or “breakthrough tank”, but the former was more a dual-purpose (infantry support and antitank) machine than the “char de rupture”. The latter concept gave birth to huge the FMC F1, with the sole purpose of terminating fortifications.

Abandoned Char B1 bis after the German invasion of France in May, 1940.

This duality was at the very core of the idea, shaping the many prototypes which followed in response. In 1921, the project was studied by a commission led by General Edmond Buat. First specification was for a low-cost self-propelled artillery, 25 mm (0.98 in) of armor and some machine-guns in turrets. Maximum metric weight was 30 tons.

The project evolved and the machine-gun turret was equipped with an antitank 47 mm (1.85 in) gun. The main gun was a 75 mm (2.95 in) howitzer, in a low hull sponson. Industrial rivalry in the past had delayed several projects, including the FCM 2C, so Estienne was poised to create a formal agreement, submitted to the industrialists involved, free to share their plans, with the promise of no less 1000 orders.

The Army was then to choose between the projects and various patents to compose their model, built by all. The four companies involved in the project were Renault and Schneider (SRA and SRB), FAMH (Saint Chamond) and FCM (Forges et Chantiers de la Méditerranée) with the FCM 21.

The four projects, one for each company, were submitted to the commission on 13 May 1924 at Atelier de Rueil. The twenty kilometer test course proved too much for them, showing the haste of their conception. The commission, over the supervision of Estienne, choose the SRB as a base.

The SRB (Schneider and Renault project) weighed 18.5 tons, was 6 meters long (19.7 ft), with modified FT tracks, an antitank 47 mm (1.85 in) gun, Renault six-cylinder 180 hp engine, with hydraulic Naëder transmission from the Chaize company combined with a Fieux clutch and Schneider gear box, a speed of 18.5 km/h (11.5 mph) and a 370 l fuel tank giving a 370 km (230 mi) autonomy.

This prototype then received many modifications, including the 75 mm (2.95 in) howitzer, new Holt-type tracks, the FAMH suspension, track tension wheel and a small gangway to access to the engine, with 40 mm (1.57 in) armor.

Captured Char B1 bis heavy tank

Design of the B1

The design process of this modified SRB led to the 1926 “tracteur 30”. The plans were made by Schneider’s chief engineer, revised by the STCC (Section Technique des Chars de Combat). A mockup was built by Renault and three prototypes were to be built by the companies involved, with some modifications by the new 1926 “direction de l’infanterie”, changing it to a primarily infantry support tank. Modifications of the design included no AT weapon, lower speed, 22 tons max and radio for coordination.

SRA prototype

The three prototypes of the “B” serie (n°101, 102 and 103) were ready by 1929-30. They differed by their engine, clutch, transmission and served both for technological and tactical experiments, at the champ de Châlons, forming the “Détachement d’Experimentation” unit in 1931. They were extensively used in maneuvers until 1934, each time with some modifications by the Atelier de Reuil near Paris, to meet new requirements and army specifications. In the end, the B1 received its final turret, with the low velocity 47 mm (1.85 in), and coaxial Reibel machine-gun.

Like the 1924 prototypes, it had a very large track, inspired by earlier famous British models. Armor also protected the suspension and the hull was riveted. The Renault inline 6 cylinder 16.5 litre petrol engine was chosen, which provided 9.7 bhp/ton, the power was transmitted by a double differential steering system, 5 forward, 1 reverse gear. Suspension was in the form of bogies with a mixture of vertical coil and leaf springs. Both early and final turret designs (APX1) were one-man only.

Char B prototype

Production: The B1

Production started in 1935, with Renault building 182 Chars B, AMX -a Schneider subsidiary- 47, FCM 72 and FAMH 70. At 1.5 million francs apiece, it was by far the costliest tank ever built en masse. Consequently, the original order of 1000 was reduced to 400. This further increased the tension between the two doctrinal schools which had influence then, one professing the use of a few, heavily armored battle tanks, while the other advocated the use of swarms of light tanks. Almost ten light Renault tanks could be built for the price of a single B1. Despite all problems, monthly production reached 41 by May 1940, and when it ceased in June, 25, 369 has left the factory floor.

As the few, even more expensive and now largely obsolete FCM 2C was kept out of real operations, the B1 became the main French “char de rupture”, a specialized breakthrough tank in specialized units. Operational capabilities were limited by their high consumption, which in turn limited their range and condemned them to be used in strategic reserves. In fact they formed the “Divisions Cuirassées de Réserve” (DCR) with limited strategic flexibility, intended for the second phase of the assault.

The B1 had some shortcomings which had to be dealt with. An obvious lack of antitank firepower, with its low velocity L27/6 SA34 47 mm (1.85 in), which was only given APHE rounds (high explosive), capable of defeating 25 mm (0.98 in) of armor. The 75 mm (2.95 in) SA35 ABS L17.1 howitzer could fire HE and APHE rounds, only suitable against fortifications, with a poor traverse of only one degree. The aiming was given to the driver’s abilities with the Naëder hydraulic precision transmission.

It was served by the radioman and the commander, who was also given the task of aiming and firing the turret 47 mm (1.85 in) gun. Communication was assumed by an ER53 radio telegraphy set, which worked with Morse code only. There was a small corridor, right on the rear, giving access to the ammunition reserve, next to the engine. The main access door was on the right side. The suspension system was rather complicated, made of three main bogies, sprung by vertical coil springs, each supporting two others, with a pair of road wheels. Production of the B1 was very slow. Only 34 machines were delivered until July 1937. By then, there was serious consideration given to an upgrade, which led to the B1 bis.

The upgraded B1 bis and B1 ter

The B1 bis was a modernization of the type, with an emphasis on anti-tank capability and protection. The armor was uprated to 60 mm (2.36 in), and a new APX4 turret with a longer barrel (L/32) SA 35 47 mm (1.85 in) gun was mounted. To cope with the added weight (now 31 tons), a new engine was fitted, a V12 Renault capable of 307 bhp (229 kW). 35 of the first series were retrofitted with the new engine. Autonomy was limited to only 180 km (110 mi).

There had been some attempts of towing an extra 800 l fuel tank, but it never realized. At cruise speed, reserves were exhausted in just 6 hours. A larger left air intake was fitted. Ammunition storage was improved between the beginning and the end of the production, from 62 to 72 47 mm (1.85 in) rounds, but still, no AP shells. Production started in April 1937 and stopped in June 1940. By then, 377 had been delivered out of an order of 1144, but only 129 were ready in September 1939.

In exercises, the complex and advanced hydrostatic steering Naëder system proved difficult to use and costly, betrayed by other technical elements like a porous bronze housing and feeble seals causing significant losses of castor oil. The TSF was not practical, as the tanks needed to be at rest to communicate. No tactical coordination was possible on the move. The costly turret was slower to produce than the hulls and three B1 bis were ultimately put in service without turret, as gun carriages.

The B1 ter was a late attempt to radically improve the design. The main features were new 75 mm (2.95 in) armor welded with slopes to the hull, a new 350 bhp engine to deal with this added weight (36.6 tons) and some simplification in the design for mass-production in 1940, like the omittance of the Naëder transmission. Rearranged interior allowed a fifth crew member to be carried, as a mechanic. The main howitzer received better traverse, 5 degrees higher. Only two prototypes were ready by June 1940. Production never started.

The B1 had some additional flaws as well, which never helped its performances. High consumption issue, which was aggravated by any aiming of the main howitzer, was never solved. The absence of an efficient compass orientation and no internal communication system were also resented in operations. The one-man APX-1 turret was also cramped, ergonomics were poor, and the feebly armored cupola had inadequate means of vision. Plus, the barrel pointing device was quickly deregulated.

Many other issues were never solved because of the delays. The most serious was of course disastrous tactical management. B1s were “wasted” at individual defensive spots, many were simply outmaneuvered. But despite all this, the B1s were still, tank to tank, formidable machines, which proved very effective in single actions.

The B1 bis in action

Despite its obsolete features, low autonomy and speed, the B1 was hard to stop. Its most formidable assets were its huge armor and good firepower, then unmatched in the west. The 60 mm (2.36 in) frontal armor was sloped, which mean it was near 80 mm (3.15 in) effectively. There were no real weak spots, and this invulnerability helped the B1 to close on targets, then destroy them with the turret 47 mm (1.85 in) or the brute force of the howitzer HE shells.

Scuttled B1 bis at Beaumont, June 1940

For this reasons, the B1 was the Wehrmacht’s most feared enemy tank, a mechanized nightmare which caused heavy casualties by itself during the few fights in which it was engaged. The Germans never experienced such losses in tank to tank combat until the fall of 1941, when encountering the Soviet KV-1 and T-34. The Panzer I and II were absolutely harmless to the B1, and the Panzer III, with its thin armor and 37 mm (1.46 in) gun, presented no serious threat to the French heavy tank. As for the Panzer IV, it had only 20 mm (0.79 in) protection (Ausf. A).

It’s standard gun was the low velocity, short barrel 75 mm (2.95 in) KwK 37, which was only effective at short range. For this reasons, the Panzer IV barely presented a real threat except in close, real time coordination with other vehicles. The same could be said about most German antitank guns of the time. The famous standard-issue “door-knocker” Pak 37 and even the Pak 40 were harmless. Contrary to common opinion of the time, the large ventilation exhaust panel was indirectly 55 mm (2.17 in) strong and never presented a weak point.

When the war broke out in September 1939, there were perhaps 180 operational B1 and B1 bis in all. They were used for the Sarre offensive, a short-lived burst without serious opposition, with a massive force of 41 divisions and 2400 tanks. The aim was to distract and divert German forces from Poland, France’s ally. After slowly penetrating 8 km (5 mi) into enemy territory, the entire force withdrew by order of general Gamelin into the security of the Maginot line. Several officers, including Henri Giraud and Charles de Gaulle, wildly protested. In effect, the Germans would have been in great danger and the Rhine was in reach. But Gamelin then was so confident about the famous fortified line, that he saw any large-scale offensive to be a useless waste of material and men.

During the “Phoney War”, all B1s were gathered in massive infantry support divisions, the “division cuirassés de réserve” or DCR, which were tactically committed in the second phase of any assault, the first being led by cavalry tanks like the SOMUA S35. No tanks were sent in Norway, but the real deal began in May 1940.

Three DCR, comprising 69 tanks each, were mobilized. Part of the 37th Bataillon de Chars de Combat, which comprised only B1s, were all rearmed with long-barrel SA 35 guns in May 1940 (turret designation APX1A). After the German invasion began, four new DCR of 52 B1s were constituted, as well as five Compagnie Autonome de Chars (autonomous tanks companies), with 56 B1s in all, plus 34 more in the 28 BCC (Bataillon de chars de combat). All B1s were reequipped with phonic versions of the ER53 radios, and command tanks received ER55 long-range radios.

B1 tanks were used (and lost) during the first phase of the operations, especially the first week. Most counter-offensives against Guderian’s “run to the sea” counted at least several B1s. Without air support, these moves were doomed to fail against the quick and lethal Stuka attacks. Bad tactics of course brought these precious tanks to inept, hasty defensive “plugs” in the defensive lines, most of the time, ending in pure waste.

In some case, the B1’s extraordinary sturdiness allowed some success, notably the counter-attacks at Laon and Moncornet led by col. De Gaulle, and stiff resistance like at Hannut and particularly Stonne. During these events, some individual B1s blocked the German advance by themselves, inflicting horrendous casualties. In a particular case, a single B1, Eure, commanded by Captain Pierre Billotte, attacked frontally and single-handedly destroyed thirteen Panzer IIIs and IVs, and then withdrew, while being hit 140 times.

During two days, B1 tanks from the 3rd Division Cuirassée de Réserve literally ruled the battlefield at Stonne, destruction coming only due to German overwhelming attacks against single tanks and excellent communication, air strikes and indirect fire (by German howitzers). Some B1s also broke down or ran out of ammunition and petrol. The last surviving B1s were mixed with other tanks in support of the so-called “hedgehogs”, which fell one after the other in June 1940. By the 26th of June, the campaign was over.

B1/B1 bis fate: German and French service

The Germans captured hundreds of tanks, including no less than 161 B1 bis tanks, later pressed into service as Panzerkampfwagen B-2 740(f). Sixty were converted into flamethrower versions (Flammwagen auf Panzerkampfwagen B-2 (f)), and sixteen to carry the 105 mm (4.13 in) howitzer. A single unit was equipped only with B1s, the Panzer-Abteilung 213, stationed in the British Channel Islands. One of these ended at the Bovington museum, repainted in French colors. 17 units in all received modified B1s, as they saw service in the Balkans (March-April 1941) and the Eastern Front, where their armor and armament proved well-adapted against Russian heavy tanks.

This surviving Char B1 bis can be seen in the French village of Stonne (Photo: Wolfgang Vinter)

By 1944, they were all gone. Those stationed in France took part in the defense of Normandy, and others were stationed in support of the German units defending Paris. In August 1944 some were captured by insurgents and used for punctual actions by local FFI units. In 1945, German pockets of resistance in France, especially those on the western coast, were left to the FFI and the regular French 1st army. Edmond Voillaume’s 2nd Company was equipped with 19 B1s, which decisively took part in the reduction of the Royan pocket, and La Rochelle. B1s were also part of the 13th Dragoon Regiment, which took part in operations in Alsace and Southern Germany. They were stationed after V-day in the French occupied zone, until the unit was disbanded in 1946.

Links

Char B1 bis – Main article on Wikipedia
Char B1 bis on Military Factory
Char B1 bis on Tank-Hunter.com

Char B1 bis Specifications

Dimensions (l-w-h) 6.37 x 2.46 x 2.79 m (20.8 x 8.07 x 9.15 ft)
Total weight, battle ready 28 tons (56,000 lbs)
Crew 4 (driver, main gunner, sec. gunner, commander)
Propulsion Renault 6-cyl inline, 16.5 l, 272 bhp
Speed (road/off road) 28/21 km/h (17/13 mph)
Range (road/off road)-fuel 200 km (120 mi)-400 l
Armament 75 mm (2.95 in) ABS SA35 Howitzer (hull)
47 mm (1.85 in) SA 35 AT gun (turret)
Reibel 7.5 mm (0.295 in) machine-gun
Maximum armor 60 mm (2.36 in)
Total production 369

Tetrarch, Light Tank Mk. VII

 United Kingdom (1938)
Airborne Light Tank – 100 built

At the start of the 20th century, nations at war experienced rapid technological advancement, and with this development came a time of adaptation and experimentation. The end of the Great War saw many countries taking stock of what had been introduced and experienced, and the interwar period proved to be a time of rapid development, testing, and theorizing, of which armored vehicles were no exception. The British Army saw fit to change the makeup of their forces to accommodate new tanks and therefore broke the vehicle design into three groups; light tanks, cruiser tanks, and infantry tanks.

Infantry tanks were designed to provide armored support for infantry units, so speed was not a focus. The Royal Tank Corps, and the Cavalry Corps however, both requested faster Armored Fighting Vehicles (AFV) to fill the roles of rapid breakthrough exploitation and reconnaissance. These ‘cruiser tanks’ were used as mechanized cavalry, utilizing lighter arms, and lighter armor than infantry tanks. The final category, light tanks, were designed to scout enemy positions, and act as policing vehicles for occupational forces, and as such, they consisted of minimal armor, and usually were only armed with machine guns. The Vickers-Armstrongs’ series of light tanks proved popular for the British Army. As a result, British and Commonwealth nations used the Vickers-Armstrongs Light Tank Mk VI extensively from the mid to late 1930’s. Due to its popularity, the Mk.VI was still in operational use at the start of World War II, however, chief tank designer Leslie Little was working on a private project to replace the Mk.VI, which would form the basis for the new Mark. VII Tetrarch. The name ‘Tetrarch’ is the Roman title given to the governor of one of four provinces of territory, or the Greek word for ‘ruler’).

Tetrarch light tank at the Armoured Fighting Vehicle School, Gunnery Wing at Lulworth in Dorset, 25th of March 1943. Source: Imperial War Museum Collection

Development

When the British Expeditionary Force was deployed in Europe from 1939 to 1940, a majority of the armor available consisted of the Mk.VI. However, the Vickers-Armstrong company was developing the Light Tank Mk.VII. Starting the design in 1937, and proposed to the War Office in 1938, the “Purdah” (meaning a state of seclusion or secrecy) tank as it was nicknamed, was sent to trials by 1938. Originally, the Mk. VII was put through trials designed to test its viability as a ‘light cruiser’ tank, since the British Army was still satisfied with the Mk.VI at the time, and felt that it did not need to be replaced. Eventually, though the Mk.VII was rejected for the light cruiser role, in favor of the Cruiser Tank Mk. I, A9.

Prototype Tetrarch from the factory. Note the odd muzzle break on the main weapon, and the Vickers machine gun cowling.

Trials for the Mk.VII lasted from May until June 1938, and at their completion, the War Office assigned the Mk VII a new ordnance designation; ‘A.17.’ An order was put in for a limited run of 70 Mk. VII to be built in July but the number was raised to 120 in November with two required design changes. First, the armament would be changed from a 15mm Besa main gun, and a 7.92mm Besa machine gun to an Ordnance Quick-Firing 2-pounder (40mm) gun with a coaxial 7.92mm Besa. A second requirement specified the for mounting of an external fuel tank on the rear of the vehicle to increase the operational range. In July of 1940, production started on the Mk. VII, but the War Office soon reduced the requested number of Mk. VII’s to the July 1938 number of 70, before raising it again to 100 and finally to 220.

Production

After the Mk.VII was approved for production by the War Office, the use of light tanks encountered several obstacles. In 1940, the Battle of France was ongoing, and the Vickers Mk.VI, which was better suited for light security duties, fared poorly in combat against German armor and many of the Mk.VIs were abandoned after the Battle of Dunkirk. British tank production began to focus on infantry and cruiser tanks, phasing out light tanks. Vickers production slowed due to a transfer of the Mk.VII from the plant at Elswick, Newcastle-Upon-Tyne, to the Metro-Cammell factory in Birmingham mid-1940. This was further exacerbated by Luftwaffe raids, which resulted in damaged supply lines, and also by the vehicle’s design flaws, such as a faulty cooling system. These factors pushed back the first production example to November 1940, with around 100 Mk.VIIs being produced through 1942, according to War Office documentation. These 100 tanks were given registration numbers, T.9266 to T.9365. Other sources place the number as high as 177, but this number has not been proven in official documents. In September 1941, the Mk.VII was then given the name “Tetrarch”.


General Sir Alan Brooke inspects a Tetrarch at the Army Staff College at Camberley, 6th of January 1941. Source: Imperial War Museum Collection

Design

When the Mk.VII Tetrarch was initially designed, it was meant as an upgrade to the existing Vickers Mk.VI. The armor thickness was increased to a maximum of 16mm using riveted plating, and the Henry Meadows Ltd. Type 30 twelve-cylinder engine produced up to 165 hp. The Mk.VII rode on the Christie suspension system, which used long coil springs, and the tracks utilized four road wheels, which due to their size, also acted as supports for the track return. In addition, the Mk.VII also adopted the steering mechanism used by the Universal Carriers. Turning the tank was accomplished by warping or bending the tracks from side to side, in the direction desired, providing a turning radius of around 90 feet (27.4 meters), so for tighter turns track braking was still necessary. At 7.6 tons, the Mk.VII was capable of reaching travel speeds around 64km/h (40mph).

As with most scout tanks, the crew of three worked in tight quarters, with the commander and the gunner in the turret, flanking the driver. Due to the small number crew members, it fell to the commander to fill the role of loader. By 1944 the tanks were also upgraded with a 40mm Quick Firing 2 pounder, and some received Littlejohn adaptors, increasing the velocity and trajectory of the armor piercing composite non-rigid (APCNR) rounds fired. By using the APCNR, which had a softer metal on the outside, the slightly smaller Littlejohn adaptor would compress the round, provide some resistance, and increase the pressure behind the shot. The resulting velocity would increase from 853 m/s to 1,143 m/s, giving the 2pdr the ability to penetrate about 80mm of armor from about 150m.

Pictured here is the Tetrarch with a Littlejohn adapter fitted to the end of its barrel. The vehicle also has some small rubber flaps hanging from the front. Source: Imperial War Museum Collection

Variants

Despite the troubled production sequence of the Mk.VII, and the initial lack of support from the British Army in regards to its use, two variants of the Mk.VII were produced. The first was designated the Tetrarch I CS. With this variant, the 2-pounder was replaced with a 3-inch howitzer but otherwise was mostly unchanged. The second variant was the Tetrarch DD. This version mounted a Duplex Drive and canvas screens to enable flotation and water crossings. Trials were carried out in June of 1941 with the Tetrarch in the Brent Reservoir, as it was the lightest tank available to the British Army. Due to its success, the Duplex Drive was modified for mounting on Valentine tanks, and eventually M4 Medium tanks used during Normandy.

Fitted with the experimental flotation screen, Tetrarchs were the first British tanks tested for amphibious landings. Source: British National Archives

Operational History

The first groups to receive Tetrarch Mk.VIIs were the 1st Armoured Division and the 6th Armoured Division, but when these divisions were sent to the North African Campaign, the Tetrarchs were deemed unfit for service, due to faulty cooling systems, and never shipped with the divisions. The next British use came in 1941, in which twelve Tetrarchs were withdrawn from the 1st Armoured Division, and assigned to ‘C’ Squadron of the Special Service Squadrons. Six of these Tetrarchs were deployed to Freetown, West Africa. On the 5th of May 1942, with the start of Operation Ironclad in Madagascar, six ‘B’ Squadron Valentine tanks and six ‘C’ Squadron Tetrarchs were deployed as part of the amphibious assault at the port of Antsirane. Due to 75mm artillery emplacements and entrenched Vichy forces, the attacking British forces suffered the loss of four Valentines and three Tetrarchs, but eventually the objective was taken. By the end of the operation, only three of the twelve Tetrarchs were in running condition, and they remained stationed in Madagascar until 1943.

Tetrarch exiting a Hamilcar glider. Source: British National Archives

In 1940, the War Office and the British Army expressed a desire for airborne units to have access to heavier weaponry through the use of gliders. In January of 1941, the Tetrarch tank was paired with the General Aircraft Hamilcar, and three years later, training exercises began. Due to its success, the Tetrarch was re-designated as an airborne tank. On the 5th of June 1944, advance elements of the 5th Parachute Brigade landed and cleared the landing zone of anti-glider obstacles, so that the squadrons of the 6th Airborne Armoured Reconnaissance Regiment (AARR) could land on D-Day. Of the twenty tanks that took off for Normandy, one slipped free of its restraints and caused the glider to crash, two tanks collided upon landing, and another was hit by a landing Hamilcar glider. Eleven of the Tetrarchs also became entangled in the discarded parachutes, which took considerable time for them to be freed.

These delays in freeing the equipment, and the reorganization of airborne forces saved the Tetrarchs from having to engage the counter-attacking Kampfgruppe, ‘Von Luck,’ which contained Panzer IV’s. The next day, the Tetrarchs were ordered to move to Bois de Bavent, and reconnoiter Troarn-Caen. After linking up with the 8th Parachute Battalion in Bois de Bavent, they proceeded to assist with the British advance on Normandy, providing reconnaissance for the troops. The first area they scouted was Escoville, where they engaged enemy infantry and gun emplacements, but they were forced to rely on infantry support to engage German armor. For the remainder of the operation, the AARR was used to assist in infantry reconnaissance or to relieve troops under fire so that they could be effectively replaced by fresh soldiers. On the 31st of July, the 6th AARR was placed under the control of the 5th Parachute Brigade, and used as a rapid reaction force, and were instructed to assist with minor pushes before the breakout in August. Eventually, the Tetrarchs were relegated to HQ roles, while ‘A’ Squadron of the 6th AARR began using Cromwells. The 6th AARR was withdrawn from mainland Europe in early September, with casualties totaling 10 KIA, 32 wounded, and 10 MIA, out of the 118 deployed. This would be the final time the Tetrarchs saw combat, and the final time light tanks would be used in an airborne role in WWII.

Soviet Service

In June 1941, due to the start of Operation Barbarossa, the USSR was added to Britain’s Lend-Lease program. While the Lend-Lease was originally started as a method for the United States to provide aid, the British government also participated in giving aid and planned to send a fraction of the produced Tetrarchs to the USSR. Twenty tanks were delivered on the 27th of December 1941 in Zanjan, Iran, but no further deliveries were made. After crews were trained in their use, the tanks were transferred to the 151st Tank Brigade, and were used alongside the Soviet T-26. They fit into Soviet tank doctrine, who still used light tanks for scouting and combat roles, and eventually, they saw combat when the 151st Tank Brigade was under the command of the 47th Army on the Transcaucasian Front. During fighting near the Abin River on the 27th of January 1943, the 151st experienced fifteen bailouts (the crew abandoning the tank after it was hit) in their attempt to take a hill. By the 31st of January, only fourteen tanks were still operational, and on the next day of fighting, another six were lost. Even after recovery efforts, on the 1st of February 1943, the 47th Army had only nine working Tetrarchs, and by May, only seven remained running. Due to a lack of spare materials for repairs, the number continued to dwindle as the remaining tanks were transferred to the 132nd Tank Regiment and the 5th Guards Tank Brigade. By September, only two Tetrarchs remained, and they were retired in the autumn of 1943.

Tetrarchs in use by the 21st Training Tank Regiment in Shahumyan, Armenia. March 1942. Source: warspot.ru
Tetrarchs donated to the USSR pose for the camera alongside T-34 tanks in the Caucus mountains, 1942. Notice the infantrymen riding on the Tetrarchs. Source: As taken from WorldWarPhotos.info

Legacy

The invasion of Normandy was the last time the Tetrarchs were used in combat, however, they were not disbanded until around 1950. Declared obsolete in January 1946, their role as an airborne tank was gradually replaced by the M22 Locust, which was adopted by the British armed forces in 1943, relegating the Tetrarch to training roles for their remaining four years with the 3rd Hussars. Despite the short service life of the Tetrarch and the problems which occurred during development, it still secured a unique place in history for itself. The use of light tanks in airborne operations proved the versatility of armored vehicles and paved the path for future air transportable tanks. To this day, tanks are still airlifted and dropped off in hard to access locations on the battlefield and enable rapid deployment of armor to many different environments, an idea pioneered by the Light Tank Mk.VII.

Tetrarch Specifications

Dimensions (L-W-H) 13′ 6” x 7′ 7” x 6′ 11” (4.11 m x 2.31 m x2.12 m)
Total weight 16,800 pounds (7,600 kg)
Crew 3 (Commander, gunner, driver)
Propulsion Henry Meadows Ltd. Type 30 twelve cylinder engine, producing 165 hp
Speed (road) 19 km/h (11.8 mph)
Armament Ordnance QF 2-pounder (40mm) gun (or 3 in (76.2 mm) howitzer)
1 x 7.92mm BESA machine gun
Armor 4 to 16 mm
Total production 6 Prototypes
For information about abbreviations check the Lexical Index

Links, Resources & Further Reading

Chamberlain, Peter; Ellis, Chris (2001). British and American Tanks of World War Two: The Complete Illustrated History of British, American, and Commonwealth Tanks 1933–1945. Cassell & Company. ISBN 0-7110-2898-2.
Fletcher, David (1989). Universal Tank: British Armour in the Second World War – Part 2. HMSO. ISBN 0-11-290534-X.
Flint, Keith (2006). Airborne Armour: Tetrarch, Locust, Hamilcar and the 6th Airborne Armoured Reconnaissance Regiment 1938–1950. Helion & Company. ISBN 1-874622-37-X.
Pasholok, Yuri. The Hard Fate of a Light Tank. READ HERE
Ware, Pat. (2011).British Tanks: The Second World War: Rare Photographs from Wartime Archives. Barnsley, South Yorkshire: Pen & Sword Military, ISBN 2:00281436.
Williams, Anthony G. (1999). The Vickers 40mm Class S Gun with Littlejohn Adaptor. The Cartridge Researcher: European Cartridge Research Association, http://www.quarryhs.co.uk/sgun.htm

Light Tank T1 “Cunningham”

U.S.A. (1927-32)
Light tank – 6 Prototypes

Up to the late 1920s, the United States military had relied on tank designs from overseas. This included the Tank Mk. VIII “International Liberty”, a World War One rhomboid style tank co-produced with the United Kingdom and the French designed Renault FT, known as the Light Tank M1917 in American service.

The M1917 served well into the 1920’s with the US Military. In 1927 the US Army designed a new tank to be built by James Cunningham, Son, and Company based in Rochester, New York (they were the first car company in the World to produce an automobile with a V8 engine). This tank was the Light Tank T1, sometimes known as the “T1 Cunningham”. It would be one of the United State’s first modern home built tanks.

“What is a modern tank?” You may well ask. The Renault FT is often considered to be the first modern tank, as since its appearance, tanks have more or less followed its general layout.This being a fully rotating turret, and separate crew and engine compartments. The T1 was America’s first tank to follow this design.

Development

The T1 was developed between 1927 and 1932, and would go through seven variations from T1, to T1E6. Each variation would go through upgraded weaponry, engine performance, and suspension.

The anatomy of the T1 remained mostly the same through its various versions. It’s characteristics were a rear mounted turret, an engine positioned in the front, and rear mounted drive sprockets. The exceptions were the E4 and E6 models. In these models, the turret was relocated to the center of the tank, the engine to the rear and the drive sprockets to the front.

Armament was constant. The tank carried a 37mm (1.46 in) Gun, with a coaxial M1919 .30 Cal. Machine Gun mounted in the fully rotatable hand cranked turret. The armament was mounted slightly to the right of the center line. The tank had a crew of two consisting of Commander and Driver in a set up similar to the M1917/Renault FT Light Tank. The Commander was located in the turret, and also performed the role of Gunner and Loader. It was his responsibility to service the main armament. The driver was located just in front of him.

The T1 taking part in training. Photo: As taken from worldoftanks.ru

T1 to T1E6

T1: The T1 made its first appearance in 1927 as a single prototype. Its main armament was the 37mm Short Tank Gun M1918. This gun was a US development of the Canon d’Infanterie de 37 modèle 1916 TRP, a low-velocity French Infantry Support Gun that was used in the First World War. The turret was roughly conical, with the roof sloping towards the gun. The T1’s armor ranged from 6.4mm (0.25 in) to 9.5mm (0.37 in) and was powered by a Cunningham water-cooled V8 gasoline engine, rated at 105 hp. This gave a top speed of 20 mph (32 km/h). It had an unsprung suspension, using equalizing links between the bogies to soften impacts, even so, it would have been an extremely rough ride over hard terrains. The tank weighed 7.5 tons.

The first model, T1. Photo: Public Domain, U.S. Army, Ordnance Department

T1E1: The T1E1 followed the original vehicle in 1928, there were few changes. The only major alterations consisted of the hull no longer extending beyond of the forward idler wheels, and the relocation of the fuel tanks to above the tracks. Speed was also reduced to 18 mph (29 km/h). Steering was achieved with a simple clutch-brake steering system. Four of these vehicles were produced making them the only T1s to see any kind of series production. The vehicle soon received the standardization designation of Light Tank M1, this was soon revoked, however.

The T1E1. Photo: Public Domain, U.S. Army, Ordnance Department

T1E2: Like its T1 predecessor, only one T1E2 prototype was built. It saw some major changes to its offense and defense. The E2’s armor was increased to 15mm (0.625) thick, raising the tank’s overall weight to 8.9 tons. The armament was also exchanged for a Browning 37mm Auto-Cannon, which had much higher velocity than the standard M1918 gun. It is thought this gun may have been a long barreled version of the M1924. The armament was later reverted, however, with the M1918 37mm Gun being reintroduced. A new turret was introduced that was completely conical with a flat, rimmed top. It almost had the appearance of a top hat, the E2 was the only version of the tank to have this turret. The Cunningham V8 engine had its power boosted to 132 hp, giving the tank a better power-to-weight ration. Maximum speed was only 16 mph, however, due to gear ratio changes.

T1E2 with the improved turret. Photo: Public Domain, U.S. Army, Ordnance Department

T1E3: The E3 was a further development of one of the four T1E1s. This variation was brought in 1930 by the US Ordnance Department. It could be considered as somewhat of a ‘Tankenstein’, as it was made up of a combination of parts from the T1E1 and T1E2. It was armed with the Browning Auto-Cannon, had thickened armor and more powerful engine of the E2, but kept the E1’s turret, hull and gear ratios. The E1’s gear ratios combined with the E2’s more powerful engine again increased the Tanks power-to-weight ratio, and increased the top speed to 21.9 mph (35.2 km/h). The major change to T1E3 came with the suspension, which was completely redesigned and featured hydraulic shock-absorbers and coil-springs. This gave a much smoother ride and better cross-country performance than the springless suspension of the previous models.

The T1E3 with the long barreled 37mm Browning gun. Photo: Public Domain, U.S. Army, Ordnance Department

T1E4: The T1E4, introduced in 1932, was a complete metamorphosis compared to the previous models of the T1. The layout of the vehicle was changed to having a centrally mounted turret, engine in the rear and sprocket wheels at the front. It had a new suspension based on the British Vickers 6-ton Light Tank, which the US Army had previously tested. This suspension consisted of semi-elliptic leaf-springs on articulated four-wheel bogies. The vehicle was now longer than the original 12 ft 6 in (3.810 m) of the T1 at 15 ft 5 in (4.70 m). Armament was changed to the short barrel version of the M1924 Gun. The E4, at first, retained the E1’s engine. This soon proved to be underpowered so it was replaced with another upgrade Cunningham V8 rated at 140 hp, giving the tank a top speed of 20 mph (32 km/h).

The T1E4 with the improved, Vickers derived, suspension. Photo: Public Domain, U.S. Army, Ordnance Department

T1E5: The E5 came along around same time as the E4, and was a further development of one of the T1E1 Prototypes. This model was fitted with a new steering system. Up until this model, the T1s had all used Clutch-Brake steering, which led to overall power loss when traversing the hull. This was replaced by a controlled differential steering system, otherwise known as a ‘Cletrac’ system named after the Cleveland Tractor Company who produced it. It worked by slowing down the wheels on one side of the tank, letting the faster side to swing in the direction required. Testing concurred that this was a much better method than the original Clutch-Brake, especially at higher speeds. US Ordnance promptly recommended its use for all future tracked vehicles that could exceed a speed of 6 mph (10 km/h). It is still used today on the M113 APC. The E5 was given the same Cunningham 140 hp V8 engine as the E4.

T1E6: T1E6 was the final T1 variant. This was a further development of the E4, with Cunningham Engines removed altogether. The 140 hp Cunningham V8 was replaced by a 244 hp V12, made by the American-LaFrance & Foamite Corporation, based in Summerville, South Carolina. This engine barely squeezed into the tanks engine bay, and increased the weight to 9.95 tons, even with the more powerful engine, the speed remained a controlled 20 mph (32 km/h). The T1E6 retained the M1924 main armament of the T1E4, with the same thickness of armor. However, this time it ranged from 9.5mm (0.375 inches) to 15.9mm (0.625 in).

T1E6, the final model. Photo: Public Domain, U.S. Army, Ordnance Department

Fate

The tank would never see mass production with the four T1E1s being the most tanks in the series built. The T1 was dropped in favor of a new design by the Rock Island Arsenal, the T2. The T2 would later go onto become the Combat Car/Light Tank M1, and would pave the way for famous American light tanks such as the M3 and M5 Stuart.

Just one of the Cunningham T1 survives today. The tank had previously sat (unarmed) on outdoor display at the U.S. Army Ordnance Museum at Aberdeen Proving Ground in Aberdeen, Maryland. However, when the museum closed in 2010, it was moved to the U.S. Army Ordnance Training and Heritage Center at Fort Lee, Virginia. It remains there in indoor storage, out of public display.

The tank spawned one variant, the 75mm Howitzer Motor Carriage (HMC) T1. This was a turretless T1 hull, armed with the M1 75 mm Pack Howitzer. This also stayed a prototype, with just one model built.

Links, Resources & Further Reading

Osprey Publishing, New Vanguard #245: Early US Armor, Tanks 1916–40
Presidio Press, Stuart – A History of the American Light Tank, R.P. Hunnicutt
Merriam Press, Development of Armored Vehicles Volume 1: Tanks, Ray Merriam
T1 on the Armored Vehicle Database

Light Tank T1 (T1E1) Specifications

Dimensions (L-W-H) 12″ 8.5′ x 5″ 10.5′ x 7″ 1′ (3.8 x 1.7 x 2.1 m)
Total weight, battle ready 8.3 tons
Crew 2 (Driver, Commander)
Propulsion 110 hp, Cunningham V8.
Speed (on/off road) 18 mph (29 km/h)
Armament M1918 37mm Tank Gun,
Browning M1919 .30 Cal (7.62mm) Machine Gun
Total production 4 T1E1s, 6 prototypes in general
For information about abbreviations check the Lexical Index

BT-7

Soviet Union (1935)
Fast Tank- 4965 built

Based on the BT-5

The BT-7 (Bystrochodnij Tankov or “Fast Tank” type 7) was derived from the 1930 American-built Christie tank, which had been perfected and modified into the BT-2 and BT-5 series. These were pure cavalry tanks, designed for speed, with good armament but weak armor. First designed in 1935, the BT-7 prototypes had a characteristic canted-ellipse shaped turret, were of all-electric welded construction, with new Saslavsky brakes, new main clutch and slightly thicker armor.

The tracks had a smaller pitch and fuel capacity was increased. Specifications asked that heavier guns should be mounted instead of the standard 20K model 1932/38 45 mm (1.77 in), namely the 75 mm (2.95 in) short barrel KT-26 and PS-3 howitzers for infantry support. The mantlet had a coaxial DT machine-gun and a rotating drum-type magazine for 18 rounds was stored in the rear basket. This complicated turret design was later dropped and the model BT-7 1935 was built using the BT-5 standard turret instead.

BT-7-1 in operations, carrying soldiers – Credits: Wikimedia Commons

The BT-7 Model 1935 (BT-7-1)

This first series was equipped with an adapted version of the T-26 turret, shared with the BT-5. This had a 45 mm (1.77 in) 20K gun with a coaxial DT-model machine-gun. Commander tank variants had a 71-TC radio and a horseshoe shaped frame antenna. The crew of three was unchanged and virtually all other components were similar to the BT-5, most importantly the suspension, rubberized roadwheels, drive sprockets, idlers and tracks. The engine was also the same petrol radial Mikulin M-17T (V-12) derived from a licence-built BMW. Steering was performed with a control stick and the engine had three forward and one reverse gears. Command versions were the BT-7-1(U) and BT-7-1(V) with wrap-around “horseshoe” type frame antenna.

BT-7-2 on parade – Credits: Wikimedia Commons

The BT-7M

This final evolution, sometimes called BT-7 model 1940, was born from the four experimental BT-8s. These were equipped with a new V12 diesel engine produced at the Voroshilovets factory and derived from the Hispano-Suiza 12Y aircraft engine. The BT-7M eventually showed a much higher endurance and overall range, and replaced the BT-7-2 on the production lines. They would become the ancestor of the T-34 family and were produced from 1939 to mid-1941, when the factory plants were dismantled to be relocated further east. Around 790 BT-7Ms were produced.

BT-7M without tracks, in wheeled mode, with the tracks stored on the hull – Credits: Wikimedia CoArtillery

Variants & Prototypes

BT-7 Artillery (1936)

154 of these artillery support versions were produced, characterized by a bigger drum-shaped turret (adapted from the T-28), a capacity of 50 rounds of ammunition (without radio) and most importantly a KT short-barrel howitzer. These were produced from 1936 to 1938 and upgraded to the 1939 standard. Quite heavy, they were not able to run in wheeled mode.

Artilley support version – Credits: Wikimedia Commons

BT-8 (1938)

Diesel equipped BT-7, later incorporated into the similarly modified BT-7Ms. A howitzer version was tried, but never produced, the BT-8A.

Prototypes

The KBT-7
A specially-made commander version with a fixed turret.
The OT-7
The flame-thrower variant, weighing 11.5 tons, was equipped with a side-mounted flame-projector.
The KhBT-7
A counter-chemical warfare variant, used to disperse a gas in order to protect the infantry and lay masking smokescreens.
The Genie tanks
SBT, a bridgelayer (no photos known), and the remote-operated tanks (for demolition) TTBT-7 and Thumbten-7, radio-controlled.

A BT-7 advancing at Khalkhin Gol, in 1939 – Source: Wikimedia

The BT-7 in Action

At an early point in their development, Giffard Le Quesne Martel (who pioneered the tankette concept) and General Wavell came to see the BT-7 prototypes on trials in 1935. Although not impressed by the quality of their hull construction, they were stunned by their displays of performance and eventually asked the War Office for a possible purchase. At their return in Great Britain, they pushed hard for the new Christie suspension to be adopted on the cruiser tanks. The BT-7 gradually replaced the older BT-2s, and their first wartime operations came with the borders incidents on the Mongolian/Chinese border.

A BT-7 allegedly overturned by a SC 250 bomb from a Stuka ground attack plane in July ,1941.

BT-7s equipped the 2nd Mechanized Brigade that confronted the Imperial Japanese Army at Lake Hasan in 1938. They saw heavy action (around 400 BT-7s) later at Kalkhin Gol from May to August 1939, with the 6th and 11th Tank Brigades. Their second assignment was the invasion of Poland in September, and the Winter War with Finland from December to mid-1940. In 1939, each Soviet light tank brigade counted three tank companies, for a total of 17 BT-7s or T-26s and a reserve one (7 BT-7s).

By the summer of 1941, the BT-7 found itself more capable to fight the German onslaught than the more numerous, but slower T-26. It was in effect the main battle tank of the Soviet Army. Losses were quite high, with an estimated 2000 lost due to enemy action or breakdowns in the first 12 months of Operation Barbarossa. In effect the attrition rate was enormous due to the excessive wear of the tanks, moved intensively from one place to another without appropriate maintenance or spare parts. All those abandoned and not sabotaged were later captured and integrated as Beutepanzers for auxiliary missions. Surviving Soviet BT-7s, although replaced by the T-34, were engaged on every front until the end of the war.

BT-7 Links and References

The BT-7 on Wikipedia
The BT-7 on WWIIvehicles.com
The BT-7 on Battlefield.ru

BT-7 Specifications

Dimensions (L-w-h) 5.66 x 2.41 x 2.29 m (18.6×7.11×7 ft)
Total weight, battle ready 13.8 tons (30,450 lbs)
Crew 3 (commander/loader, gunner, driver)
Propulsion Mikulin V12 M15T/M17T petrol egnine, 405 hp @1,750 rpm (298 kW)
32.6 hp/ton ratio, 790 l of fuel (167 US gal.)
Suspension Christie type
Speed road/off-road 72-86 km/h (45 to 53 mph)/ 50 km/h (31 mph) cross-country
Range (road/off road) 200 km (120 mi)
Armament (variable) 45 mm (1.77 in) model 33 or model 37 gun
1-3 x DT 7.62 mm (0.3 in) coaxial, rear (1937) and AA machine-guns
Armor 6 to 22 mm (0.24-0.87 in)
Production (BT-7) 4965

Type 95 Ha-Go

Japan (1936-43)
Light tank – about 2300 built

Designed for Motorized Warfare

The Type 95 can trace its roots as far back as 1933. Then, the Type 89 I-Go, only able to achieve infantry pace, was duly put on a replacement schedule. The Type 89 was heavy, well armored, with a moderately efficient low-velocity 57 mm (2.24 in) gun, but utterly slow. The general Army Staff put forth a demand for a lightweight fast tank, which would not only be used for infantry support, but also to spearhead motorized attacks, at truck speed. The Army Technical Bureau studied models from abroad, as a Japanese delegation attended trials of Christie tanks and Carden-Loyd tankettes, as well as French cavalry models.

A Type 95 Ha-Go, seen from the right side, preserved at the US Army ordnance museum – Credits: Wikipedia

However, the model designed in 1934 used a custom, simple suspension, with distinctive large bell cranks, which represented a large part of the hull length. The cavalry demanded a fast machine, the infantry a better protected one, but the former won in the end. The plans were ready in 1935, and Mitsubishi Heavy Industries was quickly ordered to produce a first batch of machines, but only 100 were built by 1939. After that, orders were also placed to Sagami Arsenal, Hitachi Industries, Niigata Tekkosho, Kobe Seikosho, and Kokura Arsenal. Together, they produced 1250 more machines until 1942. Mitsubishi also went on to produce 850 more vehicles.

Description

The Type 95 kyugo-shiki kei-sensha Ha-Go, also known as Ke-Go and Kyu-Go, was a rather small machine of seven tons. The crew consisted of three men, the commander, which served also the main 37 mm (1.46 in) gun, a machine-gunner, and the driver. The commander, who had multiple tasks, was overloaded, a fate similar to that of his peers in many other early tanks. The main gun was a medium-velocity Type 98 37 mm (1.46 in), 46 caliber long, Hotchkiss-inspired gun. It was reliable, had a muzzle velocity of 675 to 700 m/s, and was capable of penetrating 25 mm (0.98 in) of armor at 500 m, with its armor-piercing rounds.

But most of its shells were standard explosive rounds, as these tanks were mostly used in an anti-infantry role. Armament was completed by two Type 97 light machine guns, one in the turret rear, in a five o’clock position, and the other in the front hull. The very simple suspension system proved easy to maintain, although a single well-placed hit could disable the vehicle. Early trials also demonstrated that this system had a tendency to pitch badly, and the off-road capabilities were, at least at the beginning, severely limited even on moderately rough terrains. Later on, after several fixes, the system still gave the crew a rough ride, rendering aiming impossible on the move. The two boogies supported two wheels each, and tracks were driven through the front sprockets.

An interesting feature of the Ha-Go was located at the back of the vehicle. There was a fake bolt head. This bolt was actually a button, like a door bell. This is a relatively recent discovery. It is believed that this was used by troops behind the tank to warn the crew of their presence so they are not reversed over. If this is true, the Ha-Go is one of the first tanks to have such a feature.

Wartime Production

Despite all the manufacturers involved, only 2300 such vehicles were built. It was, by far, the most widely available and used tank in the Japanese military from 1939 to the end of the war. However, it was rendered obsolete after 1943 by the M3A3, M5 Stuart and the medium tank M4 Sherman.

Early versions differed from wartime production vehicles by their 36 caliber Type 94 main gun, with less muzzle velocity, and thus less penetration power. Also, secondary armament comprised two 6.5 mm (0.25 in) Type 91 machine guns. The engine was the old Mitsubishi 110 bhp model, already produced for the former Type 89 I-Go. 100 of these tanks were produced, all sent to China and, later, a few were given to the Manchukuo puppet state. All other production tanks, from 1937 to 1942, were as described above.

IJA identification photo

Variants

The only true main derivative was the Ke-Nu. It was an upgunned version, with main armament of the Chi-Ha (one 57 mm/2.24 in gun), produced in 1944. Other variants included a dozen crane version tanks, the Ri-Ki salvage version, the Ke-Ri, Ho-To and Ho-Ru SPG prototypes. The latter was a tank-hunter adaptation. However, the Ha-Go was scheduled in 1942 for replacement with the Type 3 Ke-Ri.

Type 2 Ka-Mi

In 1943, a chassis was used for trials of an amphibious model, intended for the Special Navy Landing Forces. This led to the Ka-Mi conversion, equipped with two floatable and detachable pontoons. Produced from 1943 to 1944, they fought in the Marianas, Marshall and Guam islands in 1944. Only 182 were ever completed.

Type 4 Ke-Nu

The Type 4 Ke-Nu was an unfortunate sub-product of the development of the Type 97 Chi-Ha. When it was apparent that the latter’s main low velocity 57 mm (2.24 in) gun was only appropriate against infantry, a new high velocity 47 mm (1.85 in) was developed and adopted by an upgraded version of the model, which became the Type 97-kai Shinhoto. Thereafter, many unused regular Chi-Ha turrets were put on Ha-Go hulls, giving birth to the Type 4 Ke-Nu. This added to its firepower, but condemned the model to close-range defense or infantry support. Plus, the Ke-Nu was somewhat heavier and slower. Only 100 were built in 1944. Most were stationed at Okinawa and Kyushu, and a few fought in Manchukuo and Korea in 1945.

Type 2 Ri-Ki

A boomed crane conversion, for salvage and towing operations, developed in 1943. Only 12, (according to most sources) were ever built and spread among many companies around the Pacific and China. It was unarmed and was found capable of towing most IJN tanks.

Ri-Ki, boom crane conversion

Prototypes

Type 3 Ke-Ri
This model was scheduled to replace the Ha-Go in 1942, when work on the design started. It was decided, due to cost and ease of production reasons, to keep the entire chassis of the Ha-Go, while mounting a brand new turret with a high velocity 47 mm (1.85 in) gun.
Type 4 Ho-To
The Ho-To was a SPG and tank destroyer mounting the Type 38 120 mm (4.72 in) howitzer. Despite its low velocity, the gun could fire armor-piercing HEAT shells. It was developed in 1945, along with the Ho-Ru, but none were ever built.
Type 5 Ho-Ru
The Ho-Ru was a light tank destroyer, which neared production in February 1945, although only one prototype was ever assembled. It had an arrangement vaguely similar to the German Jagdpanzer 38(t), with a sloped casemate and 45 mm (1.77 in) high velocity gun, which would have been able to defeat US light tanks. The suspension was also revised, with a new track with 350 mm wide links. The wheel guide pins and the drive sprocket were both rearranged.

Ke-Go, date unknown

Wartime Actions

The Type 95 was first introduced in China in 1937. Despite the few built by that time, it proved more than capable to deal with the under-equipped Chinese army, along with the Type 89. Some of them were sent to the puppet Manchukuo state army. 50 were sent to the Thai army in 1940, fighting in Burma in the campaign in the Shan States. The first serious test came in June 1939, during the Nomonhan “border incident”, were a massive force comprising Type 89, Type 95 and some Type 94 tankettes fought against Russian BT-5 and BT-7 fast tanks. The Russian tanks, despite their thin protection, were almost twice as heavy and equipped with a high velocity 45 mm (1.77 in) gun. They were able to cripple the IJN tanks at 1000 meter ranges and more, while the Japanese were only capable of answering under 600 meters.

The first Japanese-US tank battles occurred during the desperate defense of Bataan (Philippines) in December 1941, against M3 Stuarts. The later proved to have superior armor, but their crews had less experience and training, and suffered losses. In Malaya and Burma, also in December 1941, the Ha-Go was well-employed in jungle warfare, surging were they were not expected. Being light and rugged enough, they performed well in many tropical environments during the war. The Ha-Gos were also engaged almost everywhere in the Pacific, from Guadalcanal to Okinawa. In 1944, they were clearly outgunned and under-protected against bazookas, antitank rifles and even cal.50 (12.7 mm) rounds.

In August 1945, during the Manchurian Offensive, the Russians were equipped with the T-34/85s, IS-1s and many self-propelled guns, which far outgunned and outranged the Ha-Go, still the mainstay of the IJN forces there.

The Ha-Go was one of the few Japanese tanks of World War Two to be exported to other countries. The Royal Thai Army bought around 50 of the vehicles in 1940, renaming them Type 83 after the Buddhist year 2483. The tanks arrived just in time for Imperial Japan to press-gang Thailand into the service of the Axis. The Tanks were deployed in the Thai action in the Shan state of British Burma. The Tanks remained in service until 1954, and 1 of the tanks remains on the Royal Thai Army’s inventory.

French-Indochina

The Tanks were also used post war in French-Indochina, modern day Vietnam, by the occupying French military. They made a series of small upgrades to the vehicle which consisted of applique armor welded to the turret cheeks and lower glacis.

Gallery

In operation – Credits: Aviapress
China, 1940
IJA identification photo
IJA identification photo

 

Type 95 Ha-Go Specifications

Dimensions 4.38 x 2.06 x 2.18 m (14.4 x 6.8 x 7.2 ft.in)
Total weight, battle ready 7.4 tons (8.2 short tons)
Crew 3 (driver, commander/gunner, machine-gunner)
Propulsion Mitsubishi A6120VD 14.4 l, air-cooled diesel, 120 hp (90 kW)@1800 rpm
Suspension Bell crank
Armement Main: 37 mm (1.46 in) Type 98 AT gun
Secondary: 2 x Type 97 7.7 mm (0.3 in) machine guns
Armor 6 to 16 mm (0.24-0.63 in)
Top speed 45 km/h (28 mph)
Range (road/off road) 250 km (400 mi)
Total production 2300

Links, Resources and Further Reading

The Ha-Go on Wikipedia
A more exhaustive depiction on History of War
Osprey Publishing, New Vanguard #137: Japanese Tanks 1939-1945
Osprey Publishing, Elite #169: World War II Japanese Tank Tactics

 

Renault D2

France (1936-1940)
Medium tank – 100 built

Development History

Even while the Renault D1 was still in development, a heavier version was requested by a directive of the direction de l’infanterie from 23 January 1930. This called for a medium tank (the D1 was a light model), with 40 mm (1.57 in) of armor, that was faster (13.67 mph/22 km/h) than the D1, which in turn required a far more powerful engine. Negotiations ended in April-May, Renault also agreeing to build an adapted version for the colonies, the D3.

The most recognizable photo of the D2.

It was also hoped that it could replace the heavy B1 bis if the later would have been banned by an armament reduction treaty in negotiation at that time. However, this never happened, and the D2 soon became a low-priority project and the army greatly reduced the initial order of 750.

Two batches of 50 would eventually be delivered by the company, the first in 1936-37 (called model 1935) and the second, much improved, in 1940 (model 1938).

The Renault D2 Design

Three prototypes were built. The first was the Renault UZ, with a riveted hull and Renault FT turret (April 1932). It was tested at Rueil with the 503e RCC and accepted in service in December 1933. One year earlier, two welded hull prototypes had been ordered and build, to be delivered in November 1933. Nevertheless, the first batch was approved without testing the real production model. This was done in order to partially finance the cost of applying new welding techniques.

D2 prototype, 1934 – Credits: Wikimedia Commons

This building technique proposed by Renault saved weight and time. But it was a costly and complex process that Renault had a hard time to master at first, and, since production was rushed, problems immediately appeared. This was a compromise based on large flat screws, serving as bolts and rivets as well, the 40 mm (1.57 in) plates being partially welded and connected together.

In most respects, the D2 was a slightly enlarged D1, retaining many features of the previous vehicle, like the vertical coil suspension design inherited from the Renault NC 27, and NC-1/NC-2 family. The D2 was still narrow, with the turret placed forward, immediately behind the driver’s compartment, and a long, sloped back engine hood. Massive side skirts with mud chutes, similar to the former vehicles, were also retained, composed of six panels. Previous experience dictated the return rollers to be placed higher to prevent track resonance. The tracks were 35 cm (13.78 in) wide. The suspension counted three bogies, each with four road wheels, one coil spring and two shock absorbers, per side. The crew was three, the radio operator being seated next to the driver, operating the hull Reibel machine-gun (low, right side). The commander was seated in the turret. As usual in this configuration, he had to operate the gun (loading, aiming and firing), serve the coaxial machine-gun and command the tank at the same time. There was a four-speed gearbox, and four fuel tanks, giving a 100 km (62 mi) range. The D2 could cross a 2.1 m (6.89 ft) wide trench, climb a 80 cm (2.62 ft) obstacle, climb slopes of 45° and ford 120 cm (3.94 ft) deep rivers.

The prototype on trials – Credits: Wikimedia Commons

Production: Model 1935

The first batch was approved on 29 December 1934 by the Commission de Vincennes, based on the new tests performed with the three prototypes, fitted with gasoline and diesel engines. The gasoline engine was retained. The turret was bought separately from another manufacturer, the Puteaux factory near Paris, and the APX-1 was chosen, a modern, cast turret fitted with a SA-34 short barrel 47 mm gun (1.85 in) (from the same manufacturer) and a coaxial Reibeil 7.5 mm (0.29 in) machine-gun, and a hemispheric observation cupola. As usual, the commander could sit partly outside on a rear turret hatch. The turret cost was 200,000 frs, which added to the hull (410,000 frs apiece) rose the whole D2 unit cost to 610,000 frs. The first units from the batch were delivered in May 1935, the last in February 1937. The SA-34 had limited antitank capabilities. It was supplied with HE shells (obus D, muzzle velocity of 490 m/s / 1607 ft/s), and AP shells (model 1932, muzzle velocity of 480 m/s / 1574 ft/s, piercing only 25 mm/0.98 in at 100 m/328 ft). Two command vehicles were built (chassis 2016 – 2049), equipped with a second ER51 long range set.

Model 1935

D-2 Model 1938

The second batch was ordered later, in June 1938, (despite alarming tests reports reporting balance unreliability) following Renault’s assurance it could produce two hundred units a year. However, this was soon proved overoptimistic, in the political context of 1937-1938, plagued by general strikes and financial problems. The production was postponed, and there was uncertainty about possible exports to Poland or Belgium, eventually opposed by Supreme commander Maurice Gamelin, out of fear of technology transfers. The state of the first batch was so poor that their conversion into flame-thrower tanks was envisioned, while the unit tanks would be replaced by newer tanks. When the war broke out, Edouard Daladier confirmed mass production of the type, however deliveries were kept low, three-five vehicles per month, so that the entire second batch was not completed by June. The last fifteen were probably not taken in action in time.

The second batch was basically identical, mostly differing by the use of a more modern APX-4 turret, bearing a 47 mm (1.85 in) SA-35 long barrel gun, quite effective against tanks. PPLR X 160 episcopes replaced the older Chrétien type, and there was a S 190 G attachment point on the roof for an extra 7.5 mm (0.29 in) AA machine gun. Improved greasing system, modified idler wheels and sprockets, ball bearings, shorter mudguards, a new Vertex distributor and Vlex starter completed this overhaul. At the same time, older vehicles from the first batch received upgraded APX 1A turrets, and taken over at the Atelier de Rueil for rebuilding -namely to fix all the issues previously known. This process started in March 1940 and continued until May. At the same time, the flame-thrower project was maintained but never carried out despite a prototype being built in 1939.

The Renault D2 in Action

The bulk of the rebuilt D2 model 1935s were taken into the 19th BCC (Bataillon de Chars de Combat). Previously, the elite 507e RCC, then commanded by de Gaulle, received the first D2s in early 1937. By October, the unit’s organic strength was 45 tanks, the remainder being kept in reserve or for training (4 sections of three plus two command vehicles). De Gaulle, promoted to Colonel, heavily trained his crews to his cutting-edge tactics, but soon discovered that the model was plagued by mechanical unreliability and quickly worn-out, a problem further aggravated by the lack of spare parts. By September 1939, a waltz of unit names and affectations took place. Eventually De Gaulle was sent to command the reserve corp (GBC 517) of the 5th Army, and took part in the Saar offensive. These were then retired in reserve. Replacement by the second batch gradually took place, and 15 D2s of the new series were due to be sent in Norway.

Captured D2 – Credits: Bundesarchiv.

But this failed to materialize as soon as the model was proven ill-adapted to snow conditions. By the time of the Western campaign, the 19th BCC was a shadow of its former glory, reduced to a collection of worn-out vehicles, or partially rebuilt ones. However, this unit was committed together with the 345e CACC (4th DCR) under de Gaulle, into the hastily organized counter-attack at Montcornet on the 15th of May. After some readjustments, some tanks being cannibalized to keep others functional, the 345e CACC/19th BCC fought at Amiens on the 24th of May. However, only 17 tanks were serviceable and without infantry support, the attack failed. The remainder were lost due to the complete lack of maintenance and incessant use. Of 84 effectively enlisted D2s, only 21 were lost due to enemy action during the campaign, 38 being abandoned after breakdowns, others were in depots, and only 7 were still operational when the armistice was signed. The Germans managed to captured 21 D2s, but none was placed back in service. The turrets were dismounted and reused in armored trains and fortifications. No D2 has survived to this day.

Char Renault D2 Specifications

Dimensions 5.46 x 2.22 x 2.66 m (17.9 x 7.2 x 8.7 ft)
Total weight, battle ready 19.75 tons (395,000 lbs)
Crew 3 (driver, commander, gunner)
Propulsion Renault V-6, 9.5 litres, petrol engine, 150 bhp (111.9 kW)
Suspension Vertical coils springs
Maximum speed 23 km/h ( 14.3 mph )
Range/fuel 100 km (32 mi)/200l (52.83 gal)
Armament 47 mm (1.85 in) SA34 with 160 rounds (model 1935)
2xReibel 7.5 mm (0.29 in) machine guns, 2200 rounds
Armor 10-40 mm ( 0.3-1.57 in )
Total production 100

Links

Editions du barbotin, trackstory N°9 – Renault D2, a complete monography (fr/en)
GBM, Histoire & Collection, about WW2 French tanks
The D2 on Wikipedia

Škoda-CKD TNH series

Czech Republic (1938)
Light tank – 130 built

Designed for the Czech army

In 1935, ČKD began the study for a new tank to replace the LT vz. 35. This would be produced while taking profit of the wide industrial resources of Škoda Works. It was intended to be the main Czech tank, as well as its main export. The main concern was to avoid any issues of the previous model, starting with the suspension. The new model featured four large road wheels, resembling the Christie suspension, but in fact it was a conventional leaf-spring one. This gave some mobility even if the tracks were ruptured and an overall simplified, reliable and easy to maintain system. Other solutions were all well-proven, prewar features, which helped to keep cost reasonable enough both for the needs of the Czech army and the export market. And it was, like previous models, highly successful in this matter. 

The export versions – the TNH series (1935-40)

Even before the final vz. 38 was born (army designation), CKD had turned dozens of the TNH series for the export market. The TNH was the blueprint of the the latter model and was generally similar, with many differences dictated by contract modifications.

The Iranian TNHP

The first customer of the series was Iran, which received 60 TNHP from 1935 to 1937. These were equipped with one Skoda A4 37 mm (1.46 in) gun with 60 rounds and two vz.35 machine-guns with 3000 rounds, one coaxial and one in the hull. The turret was rounded and “short” compared to the latter 1938 series for the army, equipped with a small turret commander cupola. They were propelled by a Praga TN 100, having 7940 cc and giving 100 hp (73.9 kW). A single derivative (named TNH-S) was reequipped with a more powerful Scania-Vabis engine. This model was sold to the Latvian and Peruvian armies.

The Peruvian LTP

This was a derivative of the 1936 THN-S (25 built), equipped with a Scania-Vabis 1664 engine with 6 cylinders, water cooled, 7750 cc, 125 hp. The LTP weighted only 7.3 tons, with a maximum 25 mm (0.98 in) of armor. Armament comprised a Skoda vz.34 37 mm (1.45 in) main gun plus two vz.35 and one vz.30 machine-guns. They were fast (25 mph/40 km/h) and reliable, to such an extent that the Peruvian army kept most of them in service until 1988.

Peruvian LTP Real Felipe Callao Museum

The Swiss LTH (Panzerwagen 39)

24 were delivered just before the German annexation began. They were slightly bigger than the THN (7.7 tons), 4.46 m (14.63 ft) long, with 8 to 32 mm (0.31-1.26 in) of armor. The engine was the Saurer Type CT1D diesel or the Scania-Vabis 1664, which gave an average speed of 45 km/h (28 mph) on road with a range of 300 km, 200 off-road (186/124 mi). Main armament comprised a 24 mm (0.94 in) autocannon, a 7.5 mm (0.29 in) and a 6.5 mm (0.36) machine-gun. The Swiss army spread them into the 1st, 2nd, and 3rd Light Motorized Brigades.

Swiss Panzerwagen 39

The Lithuanian LTL

When Lithuania approached foreign companies for the needs of their army (still equipped with obsolescent FT 17s), both CKD and Swedish AB Landsverk competed, but only the CKD design was retained, modified as the LTL. Plans included a new armament, comprising the latest Skoda 20 mm (0.79 in) QF autocannon, plus two vz.38 machine-guns. However, none ever reached Lithuania, since it was invaded by the USSR in 1940. The 21 originally ordered and later delivered were then redesignated Lt vz.40 and saw service with the Slovakian army on the Eastern Front.

Design of the Škoda LT vz.38

The CKD-Škoda LT vz.38 (or “model 1938”) was a rather conventional, prewar design, with a riveted hull and turret, a set of two bogies sprung by leaf springs, each with its own large road wheel, rear idler, front drive sprocket, engine at the rear with the transmission tunnel in between. Despite the size of the road wheels, there were two return rollers for each side. It was a mid-size light tank, bigger and roomier than the export AH-IV tankette, which looked like a scaled-down model. It was armed with the new Skoda A7 37 mm (1.46 in) gun which was envisioned as an antitank weapon, but with provision of HE and AP shells (90 rounds). This was completed by a coaxial, but independent, ball-mounted machine gun, and a second was mounted into the hull bow. Both were vz.37 models, compact and sturdy, also produced in Great Britain under license by Besa.

The Panzer 38(t) : Wehrmacht service

The first units were delivered just when the German invasion started on 16 March 1939. Without the time required for training on the new tanks, none was operational when the Nazis proclaimed, from Prague Castle, the creation of the protectorate of Bohemia-Morava, ending, in effect, the Czech sovereignty. CKD-Praga and Škoda were taken over by the Waffenamt and production of the LT vz.38 was resumed, after modifications for German service, under the name of Panzerkampfwagen 38(t) which stands for “Tschechich”-Czech. Modifications included some finishing details, new commander cupola, but the armament remained virtually unchanged, if not for the replacement of the original Skoda machine-guns with faster MG 42s during the course of the war.

Panzer 38(t), Soviet Union, June 1941

Since Slovakian forces were now part of the Axis, surplus Panzer 38(t)s were given to the Slovakian infantry divisions which took part in Operation Barbarossa on the southern sector in the summer of 1941. Until the winter of 1942/43 at Stalingrad, they roamed into Ukraine and were badly beaten back by the massive Soviet counter-offensive. Some of these also took part in support of the Slovakian uprising between August and September 1944. Total production of the Panzer 38(t) was 1414, and as these were retired from the frontline in 1943, they were replaced by many successful derivatives like the Marder III tank hunter, the Grille SPG, the Flakpanzer 38(t), the scout Sd.Kfz.140/1 Aufklarungspanzer 38(t) and, of course, the Jagdpanzer 38(t), better known as the Hetzer (2827 built from 1944 to 1945).

Links and resources about the LT vz. 38

The LT vz. 38 as the Pzkpfw.38(t) on Wikipedia
The LT vz.38 on fronta.cz (in Czech)

Praga Skoda LT vz. 38 Specifications

Dimensions 4.60 x 2.37 x 2.25 m (15.09x 7.78 x 7.38 ft)
Total weight, battle ready 9.4 tons
Crew 3 (commander/gunner, driver, loader/radio operator)
Propulsion Praga Typ TNHPS/II, 6-cylinder, gasoline, 125 bhp (92 kW)
Speed (on/off road) 42/15 km/h (26/9 mph)
Suspension Leaf spring type
Armament Skoda 37 mm (1.46 in) A7 L/47.8
2 x 7.92 mm (0.31 in) Skoda Zb vz.37 machien guns
Armor 8 to 30 mm (0.31-1.18 in)
Range on/off road 250/100 km (160/62 mi)
Total production 130

Tanque Barbastro

Second Spanish Republic (1936?)
Light Tank – 1 built with 3 partially complete

The Republican Behemoth

The “Tanque Barbastro” is an unofficial name for a handcrafted light tank built by the local (not government) initiative early in the Spanish Civil War. The first and only completed tank was an improvised design, but production of several more was sanctioned when the project was raised with government officials. Large in size, but poorly armed, poorly armored, and suffering from a bureaucratic mess, their combat value, if any even saw combat, was probably limited. There are only two known photos of the mysterious prototype tank, and all four vehicles have an unknown fate; but they were all likely scrapped before the war’s end.

Design

The Barbastro’s design was rather pachydermic and rhombus-shaped, with the driver’s compartment apparently raised quite far off the ground. The vehicle featured a round but squat (and fully traversable) turret armed with a light machine gun – reportedly a non-Spanish variant of the Hotchkiss machine gun. There were two distinct side hatches on either side of the tank’s fighting compartment for entry of the reported four crew members. Photos show that the first version had “Grupo Construccion Tanques Barbastro” written on the side of the hull, between each of the tracks.

First Version

First version Barbastro Tank, date and location unknown, likely Sariñena.

The Barbastro Tank was designed by the Grupo de Construccion Tanques de Barbastro (Tank Construction Group of Barbastro) in the town of Barbastro (northeastern Spain), presumably in late 1936 or early 1937. This was not a government project, and appears to have been built locally in much the same way as the scores of improvised armored cars were built in the early Spanish Civil War. These vehicles were collectively known ‘los Tiznaos’ in Spanish (referring to their grimy appearance – Tiznar meaning ‘to smudge’), and were varied in design. Some were merely trucks with improvised uparmoring of sheets of metal over the original bodywork, others, such as the Construtora Field, had completely new bodywork and turrets.

Design and construction work of the Barbastro Tank was done at the workshop of Constancio Rámiz, which is thought to have been one of the best-equipped workshops in the Huesca province, as crucially, it had turning lathes to make turret parts.

This first version of the Barbastro Tank was built using recycled/salvaged materials; examples include the tracks being taken from an agricultural tractor, the engine coming from an old Ford commercial truck, and the body of the vehicle being made from scrap metal. The vehicle was given a coat of grey paint to make the scrap metal look homogeneous. The turret was fully traversable and armed with a light machine gun, believed to be a foreign-built (IE not Spanish) Hotchkiss machine gun.

There were reportedly four crew members – a driver, commander, and two others (who were presumably machine gunners).

Upon its completion, the vehicle drove to the railway station of the town of Barbastro from the workshop and was sent to Sariñena. Upon arrival, it drove to the headquarters of the Eastern Army. The tank is believed to have been used in the defense of Sariñena, where it was apparently captured in 1938, and later probably scrapped by Nationalist forces shortly after. No information is available on the vehicle’s combat performance.

Official Production

After the first vehicle’s completion, production of the Barbastro tank was presented to the Ministry of War, who authorized more standardized production of three more Barbastro tanks. However, there were some changes to be made. The new model was to be lighter, to have thicker armor, to feature two machine guns instead of one (one hull-mounted, and one turret-mounted), and to feature a more powerful Ford V-8 engine. It is unclear if the overall shape of the tank would have been much different to the first version.

First version Barbastro Tank, date and location unknown, likely Sariñena, after it was taken by Nationalist forces.

Instead of improvised armor, real armor plates were used which are reported to be 6.35mm thick (each plate being 12 x 1.5 meters in size). These were made in Valencia, and had originally been intended for gunshields of field guns. These were brought in to the workshop in Barbastro via trucks, and were fixed in place with electric welding points, and rivets.

Production Problems

Production began by assembling the basic lower hull. The engine compartment and the fighting compartment were then given four lateral holes cut in the hull in order to fit the track return rollers and running wheels.

Initially, the three vehicles were built simultaneously, however production quickly became complicated by bureaucracy, leading to two major issues.

The first issue was that the tracks were due to be made in a foundry in Barcelona, and the designers had wanted to use rubber, but due to the circumstances of the war, this was impossible, likely due to a rubber shortage. Therefore, the tracks had to be of a different material – probably some type of metal. However, the foundry workers would not start work without a striking a deal with the Barbastro’s designers. The workers wanted steel in order to reinforce the windows of their headquarters in exchange for building and fitting the tracks. This complicated the construction of the tank significantly, but one tank was eventually sent for final assembly in Barcelona. Whether or not a deal was reached with the workers in Barcelona remains unclear.

The second issue was obtaining engines for the tanks. After long negotiations with a local Ford branch, the vehicles were due to have modern and powerful Ford V-8 engines, but these apparently never arrived. The circumstances around this remain unclear, however, it is reported that the Ford branch in Barcelona (presumably the branch in question) did not start producing V-8 engines until 1939, which is a likely explanation for the issue.

As a result of these two issues, it seems as though the project was abandoned. One tank was sent to Barcelona for final assembly, with an unknown fate. The other two hulls were ready for final assembly (IE, they were missing tracks and engines), but these presumably never left the town of Barbastro.

Conclusion

The Barbastro tank is a mystery of the Spanish Civil War. Sources suggest that all that is known about the vehicles comes from photos, and some recollections from one of the designers of the project that are too scarce to provide a clearer history of the tank. The combat effectiveness of the first version of the Barbastro tank, with its improvised armor, modest armament, and huge size, was probably negligible, and it likely only served as a mobile bunker at the defense of Sariñena.

Sources:
Private correspondence with Guillem Martí Pujol and Francisco Javier Cabeza Martinez regarding the Barbastro Tank.
vehiculosblindadosdelaguerracivil.blogspot
On Aviarmor