Categories
WW2 Dutch Tanks

Carden-Loyd Mk. VI in Dutch Service

The Netherlands (1931-40)
Tankette – 5 Purchased

The Dutch army received its first tracked armored vehicle in 1927, a Renault FT tank for testing purposes. After it was trialled, the Vechtwagen Commissie (Eng: Tank Commission) suggested that more modern tanks should be acquired for testing. The Ministry of Defence did not agree, but negotiations were started with the British firm Carden-Loyd to purchase some vehicles which were meant to be mainly used during domestic troubles. A total of five Carden Loyd Mk. VI Tankettes were delivered and would remain the only tracked armored vehicles in active service with the Dutch Royal Army until war broke out in May 1940.

Two tankettes, among which the Luipaard. Photo: SOURCE

The Purchase

In 1928, the Artillerie Inrichtingen, together with the Nederlandsche Engelsche Technische Handelsmaatschappij (Eng: Dutch English Technical Trading Company), negotiated with Carden-Loyd about the purchase of six Mark VI tracked vehicles. Negotiations lasted for three years until the Dutch Minister of Defence approved the agreement.
The Dutch Army paid 10,000 guilders each for these vehicles (approximately US$58,000 in 2015 values). However, for unknown reasons, the factory could only deliver five out of six vehicles ordered. These vehicles were assigned to the Korps Rijdende Artillerie (Eng: Corps Mobile Artillery). The vehicles were transported by a trailer, bought specifically for this task, for an amount of 400 guilders (approximately US$2,300 in 2015 values). Over long distances, it was planned that the vehicles would be transported on the back of a truck.
The Minister of Defence wrote in a letter to the General Staff that the vehicles were mainly meant to be used during domestic crises. As such, he did not want to definitely assign them to the field army so they were withheld from the combined army exercises and were instead only used in small scale exercises. The vehicles received registration numbers, but the Minister did not want to give each a tactical number and instead he gave each vehicle a name: Poema (Puma, M37270), Luipaard (Leopard, M37271), Lynx (M37272), Jaguar (M37273), and Panter (Panther, M37274).

Two Mark VI vehicles in Arnhem, one of them is loaded on a GMC truck. They bear the registration numbers M37270 and M37272. Their small size stands out, especially compared to the Morris armored car in front of them. Photo: Dutch Military Archive

Design

The main production model of the Mark VI was acquired by the Dutch army. Its most distinctive features were the two armored extensions on top of the vehicle, protecting the heads of both the driver on the left and the gunner on the right. The sole machine gun could be removed from its mount on the right side. The vehicle was powered by a Ford model T engine, located in the middle of the vehicle and produced 40 bhp, which resulted in a maximum speed of 40 km/h (25 mph), as the vehicle only weighed 1,800 kg (3,968 lbs).
The armament consisted of one Vickers .303 (7.7mm) machine gun, designated Vickers M.18 in Dutch service. Approximately 1000 of these guns were acquired from Britain in 1918. In 1935, the remainder of these guns were modified to caliber 7.92 mm bullets for logistical purposes. At this time, the Vickers machine gun was mainly in use with reserve units, mounted on older planes and on the Carden-Loyd vehicles. On at least one vehicle, the Vickers machine gun was replaced by a 6.5mm Lewis machine gun, also in use by the Dutch Army and known as M.20. What made the Dutch vehicles unique, compared to the same tankettes used by other countries, is that a gun shield was installed to improve the gunner’s protection, although it limited his view.

Poema during mobilisation. On this picture, the black lined orange triangles are clearly visible. Source: Dutch National Archive

Jordaan Riots

Some of the five vehicles were used operationally for the first time in July, 1934 during the Jordaan Riots. Due to the economic crisis which was started by the Wall Street Crash in 1929, there was a high rate of unemployment in the district. Many unemployed people lived in the city of Amsterdam and when news came that the social benefits would be lowered by ten percent, riots broke out in the Jordaan district. The police responded by asking the military for help and also deployed their own armored cars.
Among the military troops deployed for this were at least two tankettes, namely the M37270 and M37272. Not much is known about their action, but a report of the responsible commander showed that the tracks were heavily worn down by the roads and running over barricades, so they had to be replaced very soon. Another problem that arose during the deployment was the transport of the vehicles. When two tankettes had to be transported back from Amsterdam to The Hague, the only trailer was located in The Hague which caused some logistical problems.


Dutch Carden-Loyd Mk. VI Tankette. Illustrated by Tank Encyclopedia’s own David Bocquelet, modified by Leander Jobse.

Service During WWII

All five vehicles, although they started to show their age, were still in active use when, despite the neutrality of the Netherlands, the country was attacked by Germany on May 10, 1940. At this time, two were located in Deventer, two at Waalhaven airfield (close to Rotterdam), and one was stationed in Amersfoort together with a Morris armored car. During the mobilisation, their registration numbers were replaced by a distinctive blacklined orange triangle, also used by the airforce.

A captured vehicle at Waalhaven airfield, being examined by Hermann Göring. The machine gun has been removed. The abbreviation K.R.A. stands for Korps Rijdende Artillerie (Eng: Corps Mobile Artillery). Photo: Author’s collection.
Unfortunately, not much is known about the vehicles stationed in Amersfoort and Deventer, however, information about the two vehicles at Waalhaven airfield is available. When the Netherlands was attacked on May 10th, 1940, German paratroopers were deployed above the western provinces, called Holland. The main goals these paratroopers had to achieve were capturing the government and the Queen, and controlling the airfields. As such, the Waalhaven airfield was also attacked. The Dutch Army was already prepared for the German attempt to take the airfields, hence why they stationed nearly all their armored vehicles at airfields.
The airfield was first bombed at 3:55 a.m. This bombing put both vehicles out of action. On one of the tankettes, the steering gear was severely damaged due to the explosions and the crew was forced to abandon the vehicle. Some dirt ended up in the machine gun barrel of the other tankette, commanded by Second Lieutenant ir. F. des Tombe. He immediately backed off and the crew tried to clean the gun. Just when they were done cleaning, the second attack started at 4:45 a.m., which also involved paratroopers. Some of them landed very close to the vehicle, so the crew tried to get away, but in doing so, the engine broke down. They eventually evacuated the vehicle and took the machine gun with them. Both tankettes fell in German hands, nearly undamaged.

Fate

After the Netherlands surrendered to Germany, all five vehicles fell into German hands. What happened to them afterward is unknown. They could have been used as beutepanzer, but given that they were already nine years in service, they were probably scrapped during the war.

Specifications

Dimensions 2.46 x 1.75 x 1.22 m (8.07 x 5.74 x 4 ft)
Total weight, battle ready 1.5 tons
Crew 2 (driver, machine-gunner)
Propulsion Ford T 4-cyl petrol, 40 bhp
Speed (road) 25 mph (40 km/h)
Range 89 mi (144 km)
Armament 0.303 in (7.62 mm) Vickers machine-gun
Armor 6 to 9 mm (0.24-0.35 in)
Total Purchased 5

Links & Resources

C.M. Schulten, J. Theil. Nederlandse Pantservoertuigen, Van Holkema & Warendorf, 1979.
J. Giesbers, A. Giesbers, R. Tas. Holland paraat! Volume 2, Giesbers Media, 2016.
Dr. L. de Jong, Het Koninkrijk der Nederlanden in de Tweede Wereldoorlog Deel 3 Mei 1940, staatsuitgeverij, 1970.
Hoefer, Armamentaria 3, Stichting Het Nederlandse Leger- en Wapenmuseum, 1969.
Beeldbankwo2.nl ‘Pantser rupswiel tanks waarin mitrailleurs trekken door de straten.’
waroverholland.nl
Historicalstatistics.org was used to convert currency
[youtube https://www.youtube.com/watch?v=IULgzrkmY7s]

Categories
WW2 Dutch Tanks WW2 US Medium Tanks

Marmon-Herrington MTLS-1GI4

USA/KNIL (1941-57)
Medium Tank – 125 Built

The Marmon-Herrington MTLS-1G14 is probably the most unusual tank produced by the Marmon-Herrington company before and during the Second World War. During the spring of 1941, 200 pieces were ordered by the Netherlands Purchase Commision for the Royal Netherlands East Indies Army (Koninklijk Nederlandsch-Indisch Leger, abbreviated to ‘KNIL’), in a desperate move to equip its army with armor. Armed with twin 37mm guns and up to 7 machine guns, the tank was a one of a kind.

The MTLS at Aberdeen. The unusual machine-gun mount in the side of the turret stands out. Photo: Nicholas ‘The Chieftain’ Moran

Dutch order

Starting in 1936, the KNIL tried to re-equip its army, as it had been neglected for nearly twenty years. Four Vickers tanks were obtained and, satisfied with the results of testing, the KNIL placed an order for 73 light tanks and 45 gun-armed command tanks, but due to the outbreak of the war, only 20 light tanks were delivered before the UK blocked all exports. So, the KNIL turned to the United States and bought a total of 628 Marmon-Herrington tanks instead. Two hundred of these were the MTLS-1G14 model. It was agreed that the complete order of CTMS and CTLS and 100 MTLS tanks should be delivered before the 1st July 1942. Due to the company having no experience handling an order this big, they suffered from huge production delays and only a small number of the CTLS made it to the East Indies before Java was occupied by the Japanese and all transports were canceled. The production order was taken over by the US Army and production of the 200 MTLS would be stopped by the US after 125 pieces were built.

Both pictures taken at Aberdeen Proving Grounds. Photo: Nicholas ‘The Chieftain’ Moran

Design

The MTLS tank was an enlarged version of the CTMS tank which, in turn, was based on the Combat Tank Light series (CTL), designed by Marmon-Herrington in the mid-1930’s. Although the vertical volute spring suspension was reinforced compared to the CTL tanks, it was not really fit to support a weight of 22 US tons (20,000kg). The armor thickness varied between 1½ inches (38mm) at the front and ½ inch (13mm) on top. The tracks were 18 inches (46cm) wide. The Hercules gasoline engine produced 240 horsepower and resulted in a maximum speed of 25 miles per hour (40 kph).
The twin mounted 37mm L.44 guns were designed by the American Armament Corporation. Both could be loaded with a clip of five shells. When firing fully automatically, they could fire one-eighth of a second after one another. A .30 cal machine-gun was mounted coaxially. Another one was ball-mounted in the right front sidewall of the turret and faced forwards. Two machine-guns could be mounted on the back of the turret and serve as anti-air guns. Two more machine-guns were mounted fixed in the hull, although most of the times only one was installed, while a seventh was located in a ball-mount.
The MTLS had some severe design flaws, as the vehicle was essentially an enlarged version of a vehicle weighing less than 10 US tons, now coming in at 22 US tons. The increased weight had a severe impact on the suspension and overall structure of the vehicle, making it very unreliable. Furthermore, the increase of the number of crewmen from two to four was not well taken into account and, as a result, the complete crew had to enter through the hatch on top of the turret, which would be rather inconvenient in a combat situation.

Fit for US service?

One MTLS was tested at the Aberdeen Proving Grounds by the US starting in April 1943 and continuing until November. The test results were clearly stated in the report: “The vehicle is thoroughly unreliable, mechanically and structurally unsound, underpowered and equipped with unsatisfactory armament. The 4-Man Dutch Tank Model MTLS-1G14 is not a satisfactory combat vehicle for any branch of the Armed Forces”. However, in 1946, the vehicle was still present at Aberdeen, together with the CTMS tank, which was also tested, but what happened to them afterward is unknown.

An MTLS, next to an M22 Locust airborne tank, also produced by Marmon-Herrington. Photo: Aviarmor.net


Illustration of the Marmon-Herrington MTLS-1GI4 light tank. The vehicle is missing its hull machine-gun. Illustrated by Jaroslaw “Jarja” Janas and sponsored by Deadly Dilemma through our Patreon page

Sent to Suriname

Although the Netherlands was occupied by the Germans and the Dutch Indies were occupied by the Japanese, the Kingdom of the Netherlands still possessed colonies in Latin America. These were very important for the US as they provided oil and most of the bauxite that was needed for the production of aluminum. For defense, first American troops, but later troops from Puerto Rico were stationed at these Dutch colonies. Furthermore, a Tank Battalion (Bataljon Vechtwagens) was founded in May 1942, based in Suriname.
Together with 28 CTLS and 26 CTMS tanks, 19 MTLS tanks were sent to Suriname. They were operated by the battalion which consisted out of a marines detachment, about eighty men and a detachment from the Prinses Irene Brigade, with 225 men and soldiers that were already stationed in Suriname. However, the Dutch Army could not directly provide enough resources to maintain a full battalion, which lacked personnel and accommodation, but a ‘half-battalion’ was formed during the summer of 1943. Unfortunately, the marines detachment moved to the USA in September 1943 for training and the group from the Prinses Irene Brigade also returned to England in 1943, in preparation for the planned invasion in France. To make matters worse, volunteers left to Australia to join the Dutch troops stationed there. This huge lack of personnel led to that the battalion only operated a small portion of their tanks. Plans to ship all MTLS  tanks to Indonesia after the Second World War were quickly abandoned, because it was considered to be too expensive.

Camouflaged MTLS during exercises in Suriname, 1950’s. Photo: Dutch military archives
Eventually, the tank unit was disbanded in 1946 and all tanks were put into storage. When it was decided that the tank unit should be operational again in 1947, most of the tanks were in a bad state. Rusting and lacking equipment, only a part of the 73 original tanks could be made operational. How many MTLS tanks were operational at this point is not specified. Seven years later, in 1954, only ten tanks were still operational and in 1956, this number was reduced to two, until the tank unit was discontinued in 1957. The tanks were not immediately scrapped as there is some documentation of wrecked tanks after 1957.

Picture from 1967, showing a rusted and stripped MTLS hull. Location is unknown, somewhere in Suriname.

Specifications

Dimensions (L-W-H) 4.9 x 2.64 x 2.81 m
Total weight, battle ready 20.000kg (22 US tons)
Crew 4
Propulsion Hercules water-cooled engine, 240hp
Speed 40 km/h (25mph)
Armament Dual 37mm L.44 AAC guns
Up to seven .30 cal (7.62mm) Colt or Browning machine guns
Armor 13-38mm (½”-1½” inch)

Sources

Jane’s World War II Tanks and Fighting Vehicles, The Complete Guide, Leland Ness.
World War 2 In Review: American Fighting Vehicles, Issue 2, Merriam Press.
De Surinamer: Nieuws en advertentieblad, 1 February 1949.
Presidio Press, Stuart: A History of the American Light Tank, R.P. Hunnicutt.
On mapleleafup.nl/marmonherrington, Hanno L. Spoelstra.

Categories
WW2 Dutch Tanks WW2 US Light Tanks

Marmon-Herrington CTMS-1TB1

USA/KNIL (1941) Light Tank – 194 Built

After years of neglect, the Royal Netherlands East Indies Army (Koninklijk Nederlandsch-Indisch Leger, abbreviated to ‘KNIL’) tried to re-equip itself with new material starting in 1936. Four Vickers tanks, two light and two amphibious, were acquired and the KNIL was satisfied with the results of testing them, so 73 light tanks were ordered. Furthermore, 45 gun-armed Vickers command tanks were ordered in 1939 but, due to the outbreak of the war, Britain needed all its resources and production facilities to reinforce its own army and no more than twenty light tanks and no command tanks arrived in the Indies.
In desperate need of armor, the KNIL turned to the company Marmon-Herrington, the only non-European commercial tank building company at the beginning of World War 2. In total, 628 tanks were ordered: 234 CTLS-4TA, 194 CTMS-1TB1, and 200 MTLS-1G14 tanks. These tanks were all based on the same principle design, but features were added on Dutch request. The complete order of 194 CTMS was completed, but only 31 ended up with Dutch troops in its Caribbean colonies, among which were Suriname, Aruba, Curaçao and a few smaller islands, also referred to as the ‘West Indies’. Thirty others were sent to Cuba, Ecuador, Guatemala, and Mexico respectively as part of the Lend-Lease program and were commonly known under the nickname ‘Dutch three men tank’.

The Design

The CTMS (Combat Tank Medium Series) was essentially just a bigger CTLS tank. The tracks were redesigned and wider, measuring 15 inches (38 cm). Some spare tracks were put at the front of the lower hull. Two small lights were placed on the front. The tank was propelled by a Hercules RLXDI inline-six petrol/gasoline engine. It produced 174 hp at 2600 rpm which resulted in a maximum speed of 25 mph (40 kph). The exhaust was located on the left side and covered by a grid. Three vents were located on the engine deck. The suspension was composed of vertical volute springs and four small wheels. Two return rollers guided the tracks and the sprocket was located at the front. The sliding gear transmission was manually operated with five-speed forwards and one in reverse.
The main armament was a 37mm 44 caliber automatic gun. The gun was designed by the American Armament Corporation. The standard US 37mm M5 or M6 gun did not fit in the turret. Coaxially, a .30 Cal (7.62mm) Colt machine gun was mounted. Up to three Colt machine guns could be fitted in the hull, but it appears that a maximum of two was used in any case. The gunner was provided with a telescope through which he could aim both the gun and the coaxial machine-gun. No radio was installed, although it is possible that some were mounted during local adjustments.
The vehicle weighed 13 US tons (11.340 kg), which resulted in a ground pressure of 9 psi (0,633 kg/cm2). The tank could take slopes of 50 percent. The armor consisted of bolted plates. Three vision slits were located in the front hull and one on each side. Some vision slits were located in the turret as well and were all protected by glass blocks.

In Dutch Service

As already mentioned, the KNIL ordered a total of 628 tanks. The Marmon-Herrington company, having no experience handling an order this big, suffered from huge production delays and the first planned delivery date of 165 CTLS and 140 CTMS tanks on January 1st 1942 could not be met. In fact, only a small number of the CTLS made it to the East Indies before Java was occupied by the Japanese and all transports were canceled. In the meantime, the contract was still being completed, but at this stage taken over by the US government.

A CTMS-1TB1 being inspected by Prince Bernhard of the Netherlands, 1943. Photo: network54.com Overvalwagen forum.
Now that the Indies had fallen, the only remaining free part of the Kingdom of the Netherlands was the Antilles and Dutch Guiana (Suriname). In May 1942, the Bataljon Vechtwagens (Tanks Battalion) was formed of which some personnel was already trained in the USA. The battalion was part of the Mixed Motorized Brigade and its personnel consisted of a marines detachment, about eighty men, and a detachment from the Princess Irene Brigade, of 225 men.
Within a short time, among other equipment, 73-74 tanks were sent to Suriname, 28 CTLS, 26 CTMS and 19-20 MTLS tanks. However, the Dutch Army could not directly provide enough resources to maintain a full battalion, as it lacked personnel and accommodation, but a ‘half-battalion’ was formed during the summer of 1943. Unfortunately, the marines detachment moved to the USA in September 1943 for training and the group from the Princess Irene Brigade also returned to England in 1943, in preparation for the planned invasion of France. To make matters worse, volunteers left for Australia to join the Dutch troops stationed there. This huge lack of personnel meant that the battalion could only operate a small part of their tanks.

CTMS tanks on parade in Paramaribo during the war. Photo: Dutch National Archives
When even more men were allowed to go home after the war in 1946, the tank unit had to be disbanded and all tanks were put in storage, some even left out in the open. Some sources suggest that a few tanks were sent to the Indies in 1946 to fight in the Independence war, but this has never been strongly confirmed and is quite unlikely. What happened to the single CTMS sent to Aruba and the two sent to Curacao is unknown.
In 1947, it was decided that an active cavalry unit was desired to be deployed in Suriname but many tanks were in a bad state. Turrets were rusted to the hull and many lacked armament. In 1954, not more than 10 out of the original 74 tanks were still operational. One of these lacked a turret and was used as a recovery vehicle, although it is sometimes identified as a command tank as well. In 1956, only two were still in running order and a year later, in 1957, the tank unit was discontinued. All vehicles were scrapped.

Ecuador’s First Tank

The Ecuadorian Army also got their hands on the CTMS when they tried to buy weapons after the war with Peru in 1941. Twelve vehicles were purchased from the United States and landed in the city of Guayaquil between February and March 1942 or 1943. By rail, they were transferred to the city of Quito and transferred to the newly formed Tank School Squadron no.1 (Escuadrón Escuela de Tanques no. 1). This squadron was based in the camp of the ‘Yaguachi’ Cavalry Group (Grupo de Caballería), located in the city district of La Magdalena.
The Peruvian invasion of Ecuador in 1941 and the US involvement in the Second World War hindered US Army officials from instructing or advising the Ecuadorian Army and instructors would not arrive until 1946. However, justified by the need of training in American tanks, Ecuadorian personnel was sent to the US to become tank instructors for the Ecuadorian Army. Among them were Lieutenants Reinaldo Varea Donoso, Andres Arrata Macias, and Carlos Arregui Armas.
Unlike other armies, the Ecuadorian Army was quite pleased with the performance of the tanks and were kept in service until 1959. Five vehicles were preserved and put as monuments. One is located at the National Military Academy in Quito. In southern Quito, two pairs of CTMS tanks are located at the Epiclachima Mechanized and Motorized Equipment School. Each tank bears a different nickname, the first pair was named after Indian chiefs: Atahualpa and Epiclachima. The other two are named after war heroes from the Ecuadorian-Peruvian war: Captains Juan I Pareja and Hugo Coronel. All five vehicles appear to have either new or fake guns, as the barrels seem too long.

This picture shows eight of the twelve vehicles acquired by Ecuador. Photo: SOURCE

Accompany for the CTVL

Mexico acquired four tanks in 1942 via the Lend-Lease program. They accompanied the nine Marmon-Herrington CTVL tanks already in service in 1938 in the Compañía Reducida de Tanques Ligeros (Reduced Light Tanks Company), based in Mexico City. Later, they were added to the tank group of the Brigada Motomecanizada (Mechanized Brigade). In 1955, they were taken out of service and put in storage after which all four were scrapped.

Three Mexican CTMS tanks can be seen together with three Marmon-Herrington CTVL tanks. Nine of these were already in service with the Mexican army before the war. Photo: Sentinel Mexico Marmon Dossier 2

Marmon Herrington CTMS 1TB1
Illustration of the Marmon-Herrington CTMS-1TB1 by Tank Encyclopedia’s own David Bocquelet

The CTMS-1TB1 in Cuba

Cuba was one of the first Latin American countries that declared war on the Axis powers after the Japanese attack on Pearl Harbor in December 1941. As Cuba was an important ally in the Caribbean, it received a reasonable amount of military aid through the Lend-Lease program. Part of this aid was the delivery of eight Marmon-Herrington tanks by the U.S. Ordnance Department, which became known in the Cuban army as the ‘3 Man Dutch’. They participated in the war against the guerrillas of Fidel Castro in 1958 and so are probably the only CTMS tanks that saw real fighting. In January 1959, five were still in service and in 1960, these were modified and fitted with short-range radios. The original 37mm cannon was also replaced by a Bofors QF 20mm gun. This was probably done due to a shortage of 37mm shells, whereas for the 20mm plenty were available. In 1962, the vehicles were finally taken out of service as no spares were delivered by the US and vital components, including the engine, started to really show their age.

A Cuban mid-1950’s crew is standing on top. Their uniforms indicate that this picture was taken during the mid 1950’s. Photo: SOURCE

Guatemalan Service

The last country to receive CTMS tanks was Guatemala. Little is known about the six acquired vehicles but they were unpopular among Guatemalan troops. The vehicles ended their service as gate guards. One vehicle still survives as a monument, located beside the road Avenida De La Barranquilla in Guatemala City. The Marmon-Herrington tank in possession of the Militia Museum of New Jersey is an ex-Guatemalan vehicle. Its one of the at least three vehicles that returned to the US and were for sale in 1994.

This picture was taken during the October Revolution in 1944. In the early morning of October 20th, rebels took the Matamoros Barracks in Guatemala City, which marked the beginning of sixteen hours of combat that resulted in the overthrow of the government in office. Source: IPMS/Guatemala

The Guatemalan tanks received a three-colored camouflage scheme. Its exact colors are unknown. Source: aviarmor.net

Three Guatemalan CTMS tanks that were sent to the US to be sold in 1994, along with a Stuart and four M8 Greyhounds. Source: Wheels & Tracks 50.

The CTMS in the US

Of the 194 produced tanks, only 61 tanks were sent abroad, leaving the US Army with 133 tanks. One was sent to the Aberdeen Proving Grounds where it was thoroughly tested from February 25th until May 3rd, 1943. It drove 454 miles during these tests, after which it was concluded that the CTMS would not serve any purpose in the US Army and the entire batch of 133 was scrapped. The CTMS, together with an MTLS tank, was still present at Aberdeen in 1946, but what happened to them after that is unknown.
Apart from the CTMS at the Militia Museum, three more tanks are known to be in the US. Two vehicles, originally part of the Littlefield collection, were transferred to the Collings Foundation. These are probably ex-Guatemalan vehicles as well. The other vehicle’s location is unknown, and on photographs it appears to be in a rusty but still presentable state.

The Marmon-Herrington tank at the New Jersey Militia Museum. Photo: forum.valka.cz

CTM-3TBD

The only other produced tank from the CTMS line was the CTM-3TBD. Its hull was completely identical to the 1TB1. It was designed after the US Marine Corps had set requirements, which required a turret and a diesel engine. As such, this was the first and only Marmon-Herrington tank equipped with a diesel engine, a 123hp Hercules DXRB. Three .30 cal machine-guns were mounted in the hull. Two 12.7mm (.50 cal) machine-guns were mounted in the turret. The armor was between ¼ and ½ inch (6-13mm) thick and it weighed 20,800lbs, although it was designed to be 18,500lbs. The vehicle had a top speed of 30mph (48 kph) and a range of 125 miles (200 km). The crew consisted out of three men, commander, driver, and gunner.
Five vehicles were built for a price of US$29,780 a piece. After trials had taken place, it was concluded that the vehicles did not have an outstanding performance and it was decided by the US Marine Corps to keep buying Army tanks. The five vehicles which had been built were sent to the 2nd Seperate Tank Company, based on Uvea Island to the west of Samoa where other Marmon-Herrington tanks were already stationed. In 1943, all five were taken out of service and scrapped.

The CTM-3TBD at the production facilities of Marmon-Herrington. A total of five would be built and put in service with the US Marines until retirement in 1943. Source: mcvthf.com

Specifications

Dimensions (L-W-H) 4.2 x 2.34 x 2.45 m
Total weight, battle ready 11 long tons
Crew 2
Propulsion Hercules RLXDI inline-six gasoline engine, 174 hp at 2600 rpm
Speed 40 km/h (25mph)
Range 130km (80 miles)
Armament American Armament Cooperation automatic 37mm L.44 cannon
Up to four .30 cal Colt or Browning machine guns
Armor 13mm (½ inch) all around

Resources & Links

Presidio Press, Stuart: A History of the American Light Tank, R.P. Hunnicutt.
World War 2 In Review: American Fighting Vehicles, Issue 2, Merriam Press.
Sentinel Dossier 2, Tanque Ligero Marmon-Herrington CTMS-1TB1 Del Ejército Mexicano.
Kenneth W. Estes, Robert M. Neiman, Tanks on the Beaches: A Marine Tanker in the Great Pacific War.
AVF News, Volume 24, no.3.
Wheels & Tracks, no.23 & no.50
El Ejército Ecuatoriano en la campaña internacional de 1941 y en la post guerra.
Jane’s World War II Tanks and Fighting Vehicles, The Complete Guide, Leland Ness.
wwiiafterwwii.wordpress.com
mapleleafup.nl/marmonherrington
www.ejercitoecuatoriano.mil.ec
the.shadock.free.fr/Surviving_Panzers
www.urrib2000.narod.ru

Categories
WW2 Czechoslovak Prototypes

Kolohousenka

Czechoslovakia Czechoslovakia (1923-1930)
Artillery tractor and tank – 5 built

When the Czechoslovak army bought their first tanks in the early twenties, seven French Renault FTs, they already wanted to produce tanks in their own country. Combined with an interest in the so-called wheel-cum-track tanks, they bought the rights in 1923 to produce an agricultural tractor, modified by German tank designer Joseph Vollmer. This tractor, called WD Z 50PS, was originally produced at the Hanomag company in Hanover, Germany. Although this Czechoslovak project started as an artillery tractor, it ended up being the first tank built in Czechoslovakia

This is the original converted Hanomag tractor by Vollmer, on which the vehicles were based. On the Kolohousenka vehicles, the engine was moved to the back. Photo: warspot.ru

The Idea of Wheel-Cum-Track

Some of the main shortcomings of early tanks were their slow speed and the short life of the tracks. One solution for these problems was designed by famous American tank designer Walter Christie. Christie’s design had removable tracks so the tank could drive on its wheels. This solution is best known for its use on the Soviet BT tank series.
Another wheel-cum-track solution was more sophisticated. This solution consisted of a four-wheeled chassis merged with a tracked chassis. The wheels could be lowered or lifted and be fixed in the needed position, so the tank could either drive on its wheels or tracks. This system combined fast speed on roads with good terrain resistance, but it was very complex, resulting in difficulties in building and repairing, which led to high production costs.
Due to the positive aspects of this system, it gained wide interest in multiple countries, including Britain and Sweden. Several experimental vehicles were developed, like the Swedish Landsverk L-5 and the British Vickers D3E1, but the negative aspects meant that most projects remained in their experimental stage, including the Kolohousenka project.

Good sideview of the KH-50 tank. Note the ramps on the side and the unfolded front hatch. Photo: warspot.ru

Development

After the introduction of tracked vehicles in World War I, caterpillar-tracked vehicles also gained interest in the agricultural department of the German company Hanomag. Two of their designers, Ernst Wendeler and Boguslav Dohrn, started designing tracked tractors and came up, among others, with the WD Z 25 in 1920 and the WD Z 50 in 1921. Both of these vehicles gained interest from the Czechoslovak army and they bought respectively two of the former and four of the latter between 1923 and 1927. The rights to produce both tractors locally were also bought.
At the same time, Joseph Vollmer, who had designed tanks in World War I, designed his own wheel-cum-track system, based upon the WD Z 50. In 1923, the Ministry of Defense (Ministerstvo národní obrany or MNO) bought the documentation on his design for a total of Kč1.3 million (the equivalent of approximately US$516.750 in 2017 values). After evaluation of the design, it was thought to be suitable and the company Breitfeld-Daněk (which would later merge into Českomoravská-Kolben-Daněk) was ordered to build two experimental vehicles. Note that these vehicles were intended as artillery tractors. They also asked the companies Ringhoffer (later Tatra) and Laurin & Klement (later Škoda) to assist in the development and building process. In 1924, the first two vehicles were ready and given the designation KH-50. 50 referred to the horsepower rating of the engine and KH was the abbreviation of Kolohousenka, the merging of the Czech words ‘kolo’ and ‘housenka’, meaning ‘wheel’ and ‘caterpillar’ respectively.
These two tractors were tested in the city of Prague by the Military Technical Institute (Vojenský Technický Útvar or VTU). One of the two vehicles broke down in a very short time and was in such a bad state that it had to be scrapped. The other tractor was modified and an armored superstructure was added, together with a fully rotating turret mounting a 37mm gun. With this armored addition, the vehicle became the first Czech-built tank. Tests continued with the tank, but the army was not convinced that this tank would be a worthy acquisition and no order was placed.
In 1927, the leading company in the design, Breitfeld-Daněk, merged with the company Českomoravská-Kolben and formed CKD. This lead not to the termination of the project, instead it was decided to modify the vehicle again. The complete vehicle was revised and the engine was replaced by a more powerful WD 60PS 60hp engine. The turret was also replaced, by a round-shaped one which carried two machine guns. The designation of this modified vehicle as it now had a 60hp engine was changed to KH-60. Despite the improved performance, the army still decided not to order it, but they accepted the prototype in 1930 and it received the registration number 13362. Two more vehicles were built as tractors, which got the attention of the Soviet Union and both were sold to them in 1927. The Soviets already had the Kommunar tractors in service, which were also based on the WD 50 tractor.

The KH-50 tank showing how the ramps are used to change from tracks to wheels. Photo: Bellona Publishing
After two years, in 1929, CKD made its last attempt to improve the vehicle and sign a contract with the army. The turret was rebuilt and the lifting system of the wheels was improved and made more reliable. The engine was replaced, again by a more powerful one, with 70hp. The designation for this vehicle was now KH-70. However, the Czech army was not interested at all in buying the vehicle, because they viewed it as obsolete. The vehicle was examined by the Italian army, but if it was sold to them is unclear. Due to the failure of this latest creation, the project was finally canceled and CKD turned its attention to building ‘normal’ tanks.

Specifications

Dimensions (L-W-H) 4.5 x 2.39 x 2.53m (14.8 x 7.8 x 8.3 ft)
Total weight, battle ready 7.5-10 tons
Crew 2 (commander, driver)
Propulsion Hanomag WD 50PS, 50 hp
Speed 21.7 mph (35 kph) on wheels, 9.3 mph (15 kph) on tracks (both on road)
Range 186 miles (300) km on wheels on road
Armament 3.7 cm Škoda infantry gun
Armor 6 – 14 mm (0.24 – 0.55 in)
Total production 5

Links, Resources & Further Reading

-Czechoslovak armoured fighting vehicles 1918-1945, Bellona Publishing, by Charles K. Kliment and Hilary Louis Doyle, 1979.
-V.Francev, Ch.K.Kliment “Československa obrnena vozidla 1918-48”. Prague. 2004
-Czechoslovak heavy armored vehicles. Development, production, operational use and export of the Czechoslovak tanks, armored cars and tracked artillery tractors 1918-1956, PhDr. Ivo Pejčoch, Karlova University, Prague, 2009
docplayer.cz
www.delostrelectvocsarmady1918-1939.estranky.cz
www.trekkermuseum-otmmz.nl
utocnavozba.wz.cz


The KH-50 light tank prototype. Note the Renault FT-like turret and the tow hook at the back, possibly a remain from the original tractor.

The KH-60 had a redesigned front, a new more powerful engine and a new cylindrical turret.

The last of the series, the KH-70 had an even more powerful engine and a conical type turret with a mushroom-type cupola. Also note the tail added to the vehicle, meant to aid crossing trenches.
All illustrations done by Bernard “Escodrion” Baker. These illustrations have been sponsored by Golum through our Patreon page.

Design

The engineer who participated in the design process of this vehicle and became very successful was the Russian engineer Alexey Surin. He fled to Czechoslovakia after the Reds had won the civil war and became an engineer of CKD in 1923.
The KH-50 used the original engine, a Hanomag four-cylinder, four-stroke, water cooled 50 hp engine, but it was swapped from the front to the back of the tractor. It could be powered with either benzene, gasoline or kerosene. The KH-60 and KH-70 were both powered by more powerful engines from the same company. The driver’s position was moved from the back to the front and lowered into the hull. The front hull was redesigned and somewhat similar to the Renault FT, already in use in the Czechoslovak army.

Picture of the KH-60 tank. The main layout differences are quite good visible. The exhaustion is moved to the top of the tank and the front has been redesigned, as well as the turret. Photo: utocnavozba.wz.cz
When the first vehicle was rebuilt as a tank, the superstructure and turret were designed and built by Škoda. It consisted of riveted flat sheets of armor, and the design was inspired by the Renault FT, especially noticeable in the front armor and turret. In this turret, a 3.7cm Škoda d/27 gun was mounted. When the vehicle was rebuilt as KH-60, the turret was changed to a cylindrically shaped one, designed by CKD. This turret mounted two 7.92mm Schwarzlose vz.24 machine guns. A 47mm Vickers was also considered. A rear tail was added to the KH-70 model to improve trench crossing.
Changing from wheel to track had to be done manually by the crew. This took about fifteen minutes. The ramps to change were carried on the sides of the vehicle. With the KH-70, the time to change was reduced to ten minutes. The crew consisted out of two men, a driver, and a commander. The driver was located in front of the tank, while the commander was located in the turret and also acted as loader and gunner, the same situation as in the Renault FT. The commander could get inside via hatches installed on both sides of the vehicle. The driver could get in through hatches mounted in the front of the vehicle, again comparable to the FT.

The KH-70 tank. Only one vehicle of this type was made. Either the turret is turned, or the armament is not installed. Photo: Aviarmor.net
A distinctive feature of the vehicle were the two headlights, which were mounted on the hull. On the KH-50 tank model, they were built into the hull, resulting in two ball-like extensions. The exhaust pipe was located at the side but was moved to the top of the vehicle with the KH-60 and 70. None of the three models had a radio installed, so communication had to be performed with hand signals or flags. The engine could be reached by one hatch, covering the complete back of the vehicle, and two smaller hatches at the sides. The armor on the turret and the front was 14mm thick.

Fate

As already mentioned in the development section, one of the first two KH-50’s tractors was scrapped due to a bad break down. The other vehicle was modified as a tank and later on remodeled into the KH-60, was bought by the army and examined until 1935, when the vehicle was installed as a static monument in front of the Tank School. Although it was effectively taken out of service, it was still mentioned in German handbooks in 1939. After the German invasion of Czechoslovakia, it was taken to a German depot where it was scrapped.
It is not known what happened with the two artillery tractors delivered to the Soviet Union. No photographs are known of the vehicles in Soviet service and their fate is also unknown, as is the case with the KH-70. With the experience gained by this project, Tatra designed a wheel-cum-track tractor on their own in 1929, the Tatra KTT, but the army was not interested in this project either.
After the cancellation of the project in 1930, interest in wheel-cum-track vehicles wained, but research was still being done by both Škoda and Tatra. They received orders in 1929 to design a heavy wheel-cum-track tank and they came up with respectively the Š-III and T-III. Vollmer’s design was not allowed to be used anymore because its building rights had expired and had to be bought again if they wanted to use it. Instead, the companies had to come up with their own design. Each company built two prototypes, but they suffered from severe technical malfunctions. Like the Kolohousenka, these vehicles were a failure, and the army abandoned the idea of a wheel-cum-track vehicle for good.
Originally published on February 17, 2018

Categories
WW2 Dutch Armoured Cars

Wilton-Fijenoord Armored Car

The Netherlands (1933-45)
Armored car – 3 built

At the end of the twenties, the Dutch military slowly began to realise the importance of armored vehicles and their off-road capabilities. They developed a tactic that lighter armed armored cars should be used together with infantry to give close support, but the Royal Army (Koninklijke Landmacht) didn’t take big steps in buying new vehicles. Meanwhile, the K.N.I.L. (Royal Netherlands East Indies Army) was far less conservative in buying new vehicles. In August 1933, the Dock and shipyard company Wilton-Fijenoord Limited, based in Rotterdam, signed a contract with the Ministerie van Koloniën (Ministry of Colonies) to deliver three armored cars to the K.N.I.L.. These cars were designed upon a Krupp chassis. Plans were made to deliver three more cars a year later. On the 26th of April 1934, the first out of two cars was shipped to the Dutch Indies by the steamship Kota Tjandi.

The car at the ‘Korps Rijdende Artillerie’. Note the big unfolded headlight. Photo: Holkema & Warendorf Publishing

Design

The car was armed with three machine guns, probably the Lewis M.20 6.5 mm, of which two were mounted in the hull and one in a fully rotating turret. This turret could be turned by pedaling so the gunner could use both hands to handle the gun. Additionally, an anti-aircraft machine gun could be mounted on top of the vehicle. The machine guns in the hull had a traverse angle of 25 degrees to each side. The crew consisted of at least three people, two drivers/gunners, and one commander/gunner. If needed, the crew could be scaled up to five people, so the two hull-mounted guns could be manned by other men. If needed, the exterior of the car could be electrified so enemies or rioters could not make contact with the car. A small hatch was installed in the bottom plate, through which lachrymatory gas grenades could be thrown.
The armor was resistant to 7.9 mm S.M.K. (Stahlmantelkern) bullets from 30 meters distance. The designers tried to avoid vertical placed armor plates and the use of high-quality steel led to a good trade-off between weight and protection. The total weight of the car was around 4.5 tons. Horizontal armor plates were also avoided to reduce the chance that thrown grenades could land and stay on top of the car. The crew could enter through three hatches and the drivers had closeable openings to see, but when they were closed, the drivers could see through small slots, covered by safety glass. The commander also had a periscope to have a view of the complete surroundings.

The Wilton-Fijenoord, together with the improvised Ehrhardt armored car in Oegstgeest, captured by the German Army, May 1940. Photo: SOURCE
The engine was a Krupp four-cylinder, air-cooled engine producing 60hp (44.7 kW) at 2500 rpm. The engine was horizontally opposed and equipped with special cooling rings along which air was blown by a compressor which could blow around 1000 liters of air per second. The fuel tank had a capacity of 60 liters so the car could drive a distance between 250 and 300 km.
Power was transmitted by a single disc clutch and an Aphon gear change with four forward gears and one reverse gear. The car was equipped with an extra gear change for better off-road capabilities. As a base, the Krupp 22H143 6 x 6 (other sources state the Protze L2H43) chassis was chosen. It had three axes and six-wheel-drive and had theoretically good off-road capabilities. Maximum speed was around 70 km/h (43.5 mph) on road and around 30 km/h (18.6 mph) off-road.
The car had one driver in the front and another in the back. The smallest turning circle was 4.4 meters. The four back wheels were equipped with hydraulic brakes. Both on the front and the back, spotlights were installed, which could be folded into the superstructure. Eight lamps were installed on the inside. The tires were made of solid rubber and bulletproof. In the two boxes above the back wheels on both sides of the car, tracks were stored, which could be applied on the two back wheels, resulting in better off-road performance, and essentially making it a half-track.

The car at the ‘Korps Rijdende Artillerie’. Note the storage areas above the back wheels. Photo: Holkema & Warendorf Publishing

Wilton-Fijenoord illustration
Illustration of the Wilton-Fijenoord by Tank Encyclopedia’s own David Bocquelet

Use

When the car was tested in the Dutch counties of Noord-Brabant and Limburg, no problems occurred. During the tests of two vehicles in the Dutch Indies, however, severe problems were encountered. Firstly, it was too heavy for the local roads. Secondly, the motor heating was too excessive so kerosene had to be used, instead of common gasoline. Because of these problems, the delivery of the third vehicle was canceled and all three vehicles were brought back to the factory. The two cars in the Indies were sent back to the Netherlands. In February 1935, two out of three were sold to Brazil, together with a few Ford/Wilton-Fijenoord APC’s, where they were assigned to the Special Police Force of São Paulo. The three machine guns were removed and replaced by a device which shot lachrymatory gas or apparently flames. They received a grey color.

Destroyed Wilton–Fijenoord armored car in the internal patio of the Reichs Chancellery in Berlin. Note the destroyed Schupo-sonderwagen Benz/21 armored police car behind it.
The third vehicle, with registration number H66436, was kept in the factory in running order. On the 20th and 21st of March 1936, the ‘Amsterdamse Vrijwillige Burgerwacht’ (Voluntary Civil Guard of Amsterdam) organized an exercise and Wilton-Fijenoord decided to take part. With only two crewmembers, the car was not fully manned and when the car started its exercise, it was immediately stormed by civilians. This had to do with the ‘Jordaan riots’ of 1934 when also armored cars were used. Luckily for the crew, they could electrify the vehicle after which the civilians immediately backed off. When it drove back to Rotterdam after the successful exercise it was stormed again, so the car had to defend itself again. Back in Rotterdam, they had a collision with a civilian motor car, causing more commotion.

The two vehicles in Brazil during a police parade, April 1936. Photo: SOURCE
Although the Royal Army already showed interest in 1934 the decision was made not to buy it. Four years later though on the 1st of June 1938, it was sold to the Army as part of a tax deal, and assigned to the ‘Korps Rijdende Artillerie’ (‘Corps Mobile Artillery) but was unarmed. Negotiations with DAF about arming the vehicle stalled and the vehicle was not used in combat during the German attack in May 1940. It was captured by the German troops and was assigned to the Ordnungspolizei. The Germans used it eventually in the defense of the Reich Chancellery internal patio during the Battle of Berlin in 1945, where it got destroyed by Soviet forces.
Because the chassis was a design of the German Krupp company, they heavily got involved in the design process and after the Wilton-Fijenoord armored car was rejected by the KNIL, Krupp started to build an armored car on their own, called Gepanzerte Radfahrzeug as a replacement. Only one prototype of this vehicle was built and was eventually never sent to the Dutch Indies

Specifications

Dimensions (L-W-H) 5.065 m x 2.2 m x 2.3 m ( 16.6 x x 7.2 x 9.8 ft)
Total weight 4500 kg / 9920.8 lbs
Crew 3 – 5
Propulsion Krupp 4-stroke, 4-cylinder, air-cooled engine with 60 hp (44.7 kW) at 2500 rpm
Top speed 70 km/h (43.5 mph) road / 30 km/h (18.6 mph) off-road
Operational range 250 km / 155.3 mi
Armament 3x 7.92 mm machine guns
Armor 3-10 mm (0.11-0.39 in)

Sources:

Dr. C.M. Schulten & J. Theil, Nederlandse pantservoertuigen.
Magazine ‘Het Motorverkeer’, June 13 1934
‘Mars et historia’, number 25, 1991, C. Blijleven, page 77-81
www.kfzderwehrmacht.de
www.ecsbdefesa.com.br

Categories
WW2 Czechoslovak Prototypes

Libenska-ČKD F-IV-H

Czechoslovakia (1936-43)
Amphibious Light Tank – 2 Prototypes Built

In 1933, ČKD (Českomoravská Kolben-Daněk) built the Tančik vz. 33 (P-I), however they were not pleased with the design and started a project on their own which would become the LT vz.34 (P-II) light tank of which fifty were made. These P numbers of the vehicles designated the type of tank. I stood for tankette where II stood for Light tank, however this second category got split up into IIa and IIb in 1934, respectively standing for cavalry tank and infantry tank, so ČKD started designing and came up with the P-IIa and P-IIb in 1936

First prototype outside factory. Photo: rotanazdar.cz

Development

In October 1936, both Škoda and ČKD received orders from the Czechoslovakian Army and the VTLÚ (Vojenský technický a letecký útvar or Military Technical and Aerospace Institute) to develop the first Czechoslovakian amphibious tank. During the same year, ČKD started development and on January 29th, 1937, they delivered two alternative designs to the MNO (Ministry of Defence) which were based upon the already developed P-IIa and b tanks. With no previous amphibious tank design experience and a lack of available foreign assistance, the design process proved difficult. Engineers in Great Britain and the Soviet Union had experience with amphibious designs, but due to a deteriorated relationship with the Soviet Union, caused by the armed conflict between the Bolsheviks and Czechoslovak Legions, and a negative view of British amphibious tank designs, neither were asked to assist.
On April 28, 1937, the commander of the VTLÚ, Ing. Dr. František Kolařík wrote in a report to the MNO: “The amphibious tanks designed by the two companies are based on experience gained in manufacturing and testing light tanks, tracked tractors as well as various river vessels. Regarding the overall concept of the amphibious tanks designed by ČKD, they are both respectively based on the P-IIa and P-IIb prototype tanks, with the exception of the engine and the way the drive and gear assembly are designed. (…) The disadvantage of all projects is the need to have very tightly strung tracks when driving on ground, resulting in a considerable loss of engine power during movements and little ability to adapt to unevenness. The hull is designed with sufficient buoyancy for swimming. Each project has two propellers, which are driven by the drive axle by the ČKD projects, but the Škoda project uses a special transfer directly from the engine. Changes in direction should be performed by disengaging the drive or reducing the speed of one or the other propeller, according to ČKD, or, according to Škoda, by disengaging the propulsion of one or the other bolt or the counter-flow of one of the propellers. The ČKD project is assessed to be better suited because its whole unit is mounted at the rear of the vehicle and completely separate from the combat compartment.
After considering both proposals, the VTLÚ recommended that prototypes should be ordered from both companies, because of the difficult production of amphibious tanks and lack of experience building them. Because ČKD handed in two proposals, a choice had to be made. After comparisons, the second proposal was chosen as it had more favorable characteristics. On November 12, 1937, the MNO ordered the construction of a prototype for the price of 718.000 CZK (nowadays around $350,000). In the order, it was also stated that the prototype had to be delivered before August 12, 1938.
Work on the prototype ran until the spring of 1938. The first reports appeared on April 26 when 16 technical drawings of the vehicle were realized. The number of schematics became bigger and bigger with 47 drawings on June 30 and already a total of 262 drawings on August 6. On August 20, work on the details began and by September 13, a total of 401 schematics had been produced. The deadline was extended by the MNO to 12 October, giving two months extra time.
On October 19, the deadline was again extended to the end of the year. Two liquidation orders were proposed if the tank eventually could not be delivered. Firstly, at least a part of the tests had to be paid either by the company or the military administration. Secondly, if any tanks would be sold abroad, a percentage fee of the price would be requested for intellectual property by the government. At the start of the next month, a report came in from Libeňská Engineering that a total of 415 drawings had been made and work on all the details in the mechanical workshops progressed quickly.
By November 17, the deadline was extended again until January 12, 1939. Four days later, a conference was held at the Ministry of National Defence about the amphibious tanks. The attendants came to the conclusion that the programme shouldn’t be stopped and negotiations had to continue. The percentage fee of intellectual property had to be determined after receiving and testing the vehicles from both Škoda and ČKD, due to delivery delays.
One month later, on the 7th of December, the first engine tests were launched with both alcohol-petrol mixtures and ‘dynalkolem’, a mixture of 50% fermented alcohol, 30% benzene, and 20% gasoline. After about 4 hours, a problem occurred with the electric brake, but six days later everything worked as it was supposed to and the tests were successfully completed.
Next year, on January 25, Libeňská Engineering reported that the vehicle was working. Some months later, in April, it was announced that the vehicle was in running condition and had been tested by the factory in the river Moldau in Prague, but wasn’t officially been tested by the military. Meanwhile, work was still being done on an observation device. After the German annexation of Czechoslovakia in March 1939, work continued on the project and the German military also showed interest in the project.
From 2 to 6 May 1939, representatives of the company, which was renamed Böhmisch-Mährische Maschinenfabrik AG (BMM AG), had negotiations with the German Heereswaffenamt or German Weapons Agency. The German committee consisted of Oberstleutnant Fichtner, Dr. Olbricht, Major Tomala, Oberst Reg. Baurat Beier en Oberst Reg. Baurat Mosel. During these negotiations, it became clear that the F-IV-H wasn’t ripe for serial production and further internal testing at the factory had to take place. This request was approved, but the test results had to be sent to the German WaPrüf 6. WaPrüf is the abbreviation from ‘Waffenprüfamt’or ‘Weapons testing office’. Several of these offices formed the Heereswaffenamt. BMM AG tried to offer the F-IV-H abroad, but the German military administration blocked this and marked the project as secret.
On May 23, the Czech “Ministry of National Defense in Liquidation” extended the delivery time to 31 July. Within delivery time, on June 22, the National Engineering Research and Testing Institute, the former VTLÚ, was informed that the prototype was ready for testing. The formal reply suggested that the company should notify the German army. They indeed showed further interest and on November 2, a second prototype was ordered, which bore the name F-IV-H/II. The factory was visited by Mr. Keiling on behalf of WaPrüf 6 a month later. He promised that the prototype could remain for demonstration purposes. During the same month, the company received permission to offer the F-IV-H abroad, however, the vehicle wasn’t ordered either by the Germans or foreign countries and further development was canceled.
Meanwhile, the Škoda ŠOT had also been built and tested, but it was reportedly too heavy and could barely maneuver in the water. It is not known when the first ČKD prototype was scrapped. The second prototype was sent to Kummersdorf, where it was tested. The last trace of this vehicle was found in early 1943 when new tracks and pins were ordered, but by this time, further development had already been canceled.

First prototype without floatation skirts. Photo: rotanazdar.cz


Illustration of the ČKD F-IV-H by Tank Encyclopedia’s own Jarosław Janas

Design

Initially, ČKD came up with two alternative designs. The first design was propelled by a conventional six-cylinder water-cooled engine, with an output of 95 hp at 2000 rpm. The second design was propelled by a four-cylinder water-cooled engine with an output of 100 hp at 2000 rpm. Both alternatives had an vertical exhaust pipe, which would limit the turret traverse. The second alternative was chosen.
The crew consisted of three people; The commander/gunner, driver and a radio-operator. The driver was located in the right front of the tank and had a sight with bulletproof glass. The radio-operator sat to his left and the commander was located in the turret.

F-IV-H front interior. The driver sat to the right and the radio-operator to the left. Photo: rotanazdar.cz
The chassis was a heavily modified version of one used by the famous LT vz. 35 tank. Power was distributed through a Praga-Wilson gearbox with four road wheels and two return rollers on each side. The engine was a Praga F4 water-cooled 4-cylinder producing 120 hp at 2200 rpm. Two propellers were mounted at the rear of the vehicle and connected to the drive axle. The armament consisted of only a 7.92 mm ZB-37 machine gun, located in the turret. Frontal armour was 14 mm thick and the top and bottom armor plates were 7 mm thick.
The differences between F-IV-H prototype I and II were minor, with the II having a slightly modified turret, a lifted cupola, a better cooling system, a redesigned floating system and a new exhaust system.

Export

At the end of 1939, offers were sent to Sweden, Persia and the Netherlands. The export model received the designation F-IV-HE and was described as a fast and easily manageable combat vehicle. The armor could withstand bullet fire, even at a distance of 100-150 meters. It was suitable for both terrain or water maneuvers. The factory also stated in the offers that 20 to 25 units could be delivered per month within a maximum time span of five months.
Of the three contacted countries, only the Persian War Ministry and General Staff showed interest. In April 1940, a technical description with additional photographs was sent and further communication took place via Berlin. It was assumed that Persia would buy around 200 vehicles, including a few F-IV-H vehicles. In the end, Persia ordered only twenty vehicles and this order didn’t contain the F-IV-H. It is possible that this is due to a lack of interest of the Persian War Department, but it’s more likely a result of a restriction from the German department. Later on, a new offer was sent to Argentina, but they showed no interest either.

Conclusion

Despite the efforts of the engineers, the F-IV-H was not a successful project. The Czech army was skeptical about it because of the long delivery period and when it was tested, it did not perform as planned. Although the German continuation of the project the vehicle was still not suitable for combat and in the early stage of the war already outdated. Both prototypes were scrapped during the war.

The F-IV-H second prototype. Photo: rotanazdar.cz

ČKD F-IV-H specifications

Dimensions (L-W-H) 4.85 x 2.5 x 2.08 m (15.9 x 8.2 x 6.8 ft)
Total weight, battle ready 6.5 t (14,330 lbs)
Crew 3 (commander, driver, radio operator)
Propulsion Praga F-IV, 4-cylinder, 120 hp
Speed 45 kph / 28 mph – road, 6 kph / 3,7 mph – water
Range 200 km / 125 mi
Armament ZB vz. 37 7.92mm machinegun.
Armor 7-14 mm / 0.28 – 0.55 inches
Total production 2 Prototypes

Links, Resources & Further Reading

Czechoslovak armoured fighting vehicles 1918-1945, H.C. Doyle, C.K. Kliment
On Aviarmor.net
On tanksinworldwar2.com
On utocnavozba.wz.cz
On rotanazdar.cz
Google maps view of where the water testing took place, libeňský zámeček (libeňský mansion) HERE