Author: Mark Nash

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Flame Thrower Tank T33

United States of America (1945)
Mechanized Flame Thrower – 3 Prototypes

With M4-based mechanized flamethrowers proving highly effective against the heavily dug-in Japanese in the Pacific, development of newer versions moved quickly. In 1945, a number of experiments took place to test the possibility of mounting a powerful flamethrower coaxially with the main gun. a progression of this was designated by the United States Ordnance Committee as ‘Mechanized Flame Thrower T33
Considered by some to be “the ultimate US flamethrower of World War Two”, the T33 saw one of the more extensive modifications to its foundation M4 hull. It featured a new turret, a new cannon, and a new flame gun.

The T33 prototype at the Aberdeen Proving Grounds. Photo: Osprey Publishing

Turret

To accommodate the tank’s main gun and new coaxial flame gun, a new turret had to be designed for the T33. It was of cast construction and rather bulbous and large compared to most M4 mounted turrets. The main gun remained in the center of the turret, with the flame gun placed on the right. The projector was protected by a thick tube, which almost gives it the appearance of a short-barreled howitzer.
It was a three-man turret. The commander sat in the center at the rear, the loader was positioned on the right and the gunner on the left. This was an unusual arrangement for an American tank, as usual, crew orientation concerning the loader and gunner are the opposite way around. Above the commander was his vision cupola with built-in hatch. The gunner and loader had individual hatches above their positions.

Weaponry

The flame gun and cannon were geared together, but could also move independently of each other in elevation. The range of elevation was -15 to +45 degrees. It also had 15 degrees of traverse left and right. The particular flamethrower used in the T33 was the E20-20 (E20 fuel group combined with the E20 flame gun) which was a further development of the POA-CWS-H5 (Pacific Ocean Area-Chemical Weapons Service). This weapon was also designed in 1945 and was earmarked for use in the planned Invasion of Japan. The weapon had a range of 150 yards (137 meters).
For a long time, the standard gun of many M4 models was the 75mm Tank Gun M3. To save weight and grant extra space in the new turret, in the T33 this gun was replaced with the 75mm Lightweight Tank Gun M6 which had a concentric recoil system (a hollow tube around the barrel. A space-saving alternative to traditional recoil cylinders). This gun also served as the main armament of the Light Tank M24 Chaffee. Variants of the gun were also used on aircraft such as the B-25H Mitchell Bomber. Though one caliber shorter than the M3 (The M3 Tank Gun was 40-Calibers in length, the M6 was 39), the gun granted the same velocity of 619 m/s (2,031 ft/s) and identical maximum penetration of 109mm. Elevation range of the gun was -10 to +13 degrees. The gun also had a coaxial.30 Cal (7.62mm) Browning Machine Gun which was mounted in between the canon and flame gun. Between 40 and 55 rounds of 75mm ammunition were carried.
It was planned that, when available, the M6 gun would be replaced by a new model designated the M17. This gun was similar to the M6, but saw the introduction of a muzzle brake. The replacement would never take place, however, as no M17s would enter production.

Schematics of the layout of the flamethrower equipment inside the T33. Photo: Presidio Press
Originally, there was a specification to add an Auxiliary E21 Flame Gun to amount installed on the commander’s cupola. It could traverse 240 degrees left and right, providing close range protection from attacking infantry. It was blocked firing directly forward to avoid flaming liquid pooling on the turret roof. When the T33 pilot was constructed, the E21 was replaced with the E12R4. This was also a small auxiliary flamethrower. Two large fuel tanks were placed on the hull floor, with two smaller ones located on the left and right of the turret bustle. Total fuel capacity for the flame guns was 250 US Gallons (1137 liters).
To begin with, the tank also retained the original M4 crew of 5 (commander, gunner, and loader in the turret, with the driver and co-driver/bow gunner in the forward hull. This soon dropped to four men, however, when the bow machine gun was removed. The void was welded over.

Artist’s interpretation of the T33. As there are no known schematics, or any clear side photos, the illustrator has speculated on the details and shape of this side of the turret. Illustration by Andrei ‘Octo10’ Kirushkin, funded by our Patreon campaign.

Production

A pre-production run of 20 T33s was planned, with 300 requested for January 1946. There were further aims to construct 600 of the tanks. However, when the war with Japan ended, this was drastically cut back to just three pilots. The particular hull chosen for the T33 pilots was that of the Assault Tank M4A3E2, the famous Sherman ‘Jumbo’.
The E2 was famous for having much thicker armor than its standard M4 brothers. At maximum, the armor was 177 mm (7”) thick. The effect of which was amplified by the flat, sloped upper plate. It is interesting to note that the E2s chosen for the project were three of the only four to remain in the United States as all others were sent overseas.

A front view of the T33. Presidio Press
The standard Vertical Volute Spring Suspension (VVSS) of the E2 was replaced with the newer Horizontal Volute Spring Suspension (HVSS). This suspension had two-part wheels and used a wider track. For a heavy vehicle, which the Jumbo was, a wider track granted better weight-dispersion on soft ground making it easier to traverse.
Although the original Ford GAA V8 power plant from the standard M4A3 was retained, the final drive ratio was increased to 3.36:1. This reduced the top speed to 22 mph (35 km/h), but the tank maintained reasonable acceleration even though it now weighed 84,000 lbs (38,100 kg). It could climb a 60% slope, cross a 7’6” (2286 mm) trench, climb a 24” (609 mm) vertical wall and ford 36” (914 mm) of water.

A rear view of the T33, showing clearly the the HVSS suspension. Photo: Presidio Press

Fate

At the end of the war, the T33 was considered the most advanced flamethrower tank in existence. Although slow, work continued on these pilots after the war. The Pilot #1 arrived at Aberdeen in September 1947, Pilots #2 and 3 arrived in January 1948. The T33s took part in tests at Aberdeen, but no further production would take place.
Though the T33 did not enter service, the E20-20 and coaxial configuration did. Mounted coaxially with the 105mm Howitzer armed M4A3 (HVSS), it served during the Korean War.
In 1953, two of the T33 pilots were converted into the Self-Propelled Flame Thrower T68. This was based on the Canadian Badger project. The turrets of the T33s were removed and the void covered by sheet metal with a cupola added on top. Attached to this cupola was a mount for a .50 Cal (12.7mm) machine gun. A 220 US Gallon fuel tank fed a flamethrower gun mounted in the bow machine gun position. The tank had a crew of three, consisting of driver, commander, and flame gun operator. The T68 took part in a number of tests at Aberdeen but, like the T33, it never entered production.

An article by Mark Nash

Specifications
Total weight, battle ready	38 tonnes aprx.
Crew	5 (commander, driver, co-driver, gunner and loader)
Propulsion	Ford GAA V8, 500 hp@2600 rpm
Speed (road)	35 mph (56 km/h)
Armament	E20-20 (E20 fuel group combined with the E20 flame gun) 75mm Lightweight Tank Gun M6
Armor	Maximum 177 mm (7”)

Links, Resources & Further Reading

Presidio Press, Sherman: A History of the American Medium Tank, R. P. Hunnicutt.
Osprey Publishing, New Vanguard #206: US Flamethrower Tanks of World War II
US Army Ordnance Department report, dated 31st May 1945

WW2 British Vehicles in Foreign Service WW2 Irish Armor

Universal Carrier in Irish Service

Post author By Mark Nash
Post date June 14, 2018
No Comments on Universal Carrier in Irish Service

Republic of Ireland (1940)
Tankette – 226 Purchased

With approximately 113,000 built by the early 1960s, the Universal or ‘Bren’ Carrier is the most produced armored vehicle ever. To this end, it is perhaps no surprise that quite a large number of these carriers ended up serving with the Irish Defence Force (IDF, Irish: Fórsaí Cosanta, officially: Óglaigh na hÉireann) in the early 1940s.
The carrier was perfect for operation in a small country such as the Republic of Ireland, which is dominated by small villages and narrow country roads. Though rather mundane, the Universal Carrier became an important vehicle to Irish Armored units, as it was the first Armored Personnel Carrier (APC) type of vehicle to serve in the Irish Military.

Two carriers taking part in a parade in Dublin, the two vehicles behind are Ford Armored Cars. Photo: Irish Armor Online

The Universal Carrier

Produced by the Vickers-Armstrongs company, the Universal Carrier, often known simply as the ‘Bren Carrier’ after its common light machine gun armament, became a backbone vehicle of the Allies during the Second World War. It was widely used by the British, American, Canadian, Australian, and even Soviet armies. All made use of the unassuming little vehicle. Even the Wehrmacht made use of captured specimens and the Italians even copied it
The Carriers were powered by an 85hp Ford V8 petrol engine, propelling the vehicle to a top speed of 30 mph (48 km/h). The engine was mounted centrally in the vehicle with drive sprockets at the rear. It used a Horstmann type suspension with three-road wheels and idler wheel at the front. It was an extremely light vehicle at only 3.75 tonnes, and armor of only 7-10mm thick, sufficient to protect the crew from small arms fire and shell splinters
As mentioned above, over the course of its lifetime, 113,000 Universal carriers were built between 1940 and 1960, including a number of variants. To this day, it remains the most produced armored vehicle ever. Only the Soviet T-54/55 comes anywhere close to this record, at a predicted 100,000 built.
Three versions of the Carrier were used by the Irish Military. These were the Mk.I, Mk.II. The Mk.II was almost identical to the Mk.I apart from small differences such as a mounting for a spare wheel on the upper glacis, and the addition of a towing hitch on the rear. The Mk.I Mortar Carrier was also provided. The Mortar Carrier variant had the ability to carry a 3-inch or 81mm mortar. The mortar tube was carried at the rear of the vehicle, while the base plate was fastened to the front.

Irish Carriers in Dublin armed with a Bren light machine gun and Boys anti-tank rifle. Photo: SOURCE

The Irish Universal Carriers were painted in the same pale grey as most of the tanks that were in their service in the mid-Cold War era. Illustrated by Tank Encylopedia’s own AmazingAce, based on work by David Bocquelet.

Irish Service

The first Universal Carriers to arrive in Ireland were Mk.Is. In mid-1940, 26 of these were acquired and placed in the newly formed Carrier Squadron of the Cavalry Corps (Irish: An Cór Marcra). In January 1943, however, the Carrier Squadron was disbanded with all vehicles handed over to infantry battalions. To fully equip the infantry battalions, a further 200 carriers were ordered. This consisted of 100 of the Mk.I Mortar Carrier variant, and 100 Mk.IIs. In total, 226 Universal Carriers were purchased by the Republic of Ireland. The Carriers received the typical dull grey paint scheme used on most armored vehicles in Irish Military Service.
Each infantry battalion was equipped with 9 Carriers. This consisted of 1 carrier for the battalion Commanding Officer (CO), four Mk.I Mortar Carriers for mortar platoons, and four carriers for reconnaissance platoons. It is possible that some battalions received as many as 37 carriers as a support company consisting of a mortar platoon, two medium machine gun carrier platoons and possibly even an anti-tank platoon with towed 2-Pounder guns. It appears that at some point at least two of the Carriers were converted into flamethrowers. Whether the design of these was anything like the Canadian Wasp project is unknown.
In the 1950s, a number of Carriers were returned to service with the Cavalry Corps. They were assigned to the Corps in the arrangement of eight carriers to each Motor Squadron. In the early 1960s, with Cold War tensions rising as a result of the Cuban Missile Crisis, a small number of Carriers were stationed at McKee barracks for defence of Dublin Airport. At this time some were also converted in prime-movers for towed 6-Pounder anti-tank guns.

Restored Carrier on display at the Curragh in 2006. To the right is a preserved Cavalry Corps Comet, and behind is a Landsverk Armored Car. Photo: MMP Publications

Fate

In 1965, most of the Carrier force had been broken up for scrap. Just three of the 226 Carriers once used by the Irish Military survive. One example is on display at the Collins Barracks in Dublin. Another running example can be found in a running condition at the Curragh Cavalry Museum and is often run in parades and displays. The final Carrier is privately owned by a collector in Clonmel, but it is not in running condition.

Specifications
Dimensions	3.65 x 1.92 x 1.57 m (11.98 x 6.3 x 5.15 ft)
Total weight, battle ready	3.75 tons
Crew	2 (Driver, machine-gunner)
Propulsion	Ford V8 petrol 85 bhp at 3500 rpm
Speed	30 mph (48 km/h)
Range	150 km at medium speed (93 mi)
Armament	7.92 mm Bren machine-gun (0.31 in)
Armor	From 7 to 10 mm (0.28-0.39 in)
Total Purchased	226

Links, Resources & Further Reading

www.curragh.info
www.geocities.ws
Irish Army Vehicles: Transport and Armour since 1922 by Karl Martin
Tiger Lily Publications, Irish Army Orders of Battle 1923-2004, Adrian J. English
Mushroom Model Publications, AFVs in Irish Service Since 1922, Ralph A. Riccio

Cold War British Vehicles in Foreign Service Cold War Irish Armor

FV101 Scorpion in Irish Service

Post author By Mark Nash
Post date June 7, 2018
3 Comments on FV101 Scorpion in Irish Service

Republic of Ireland (1980)
Light Tank – 14 Purchased

In the late 1970s, the Irish Cavalry Cavalry Corps (Irish: An Cór Marcra) decided to retire their small fleet of Comet tanks purchased from Great Britain in 1958. These Second World War tanks had served well with the Cavalry corps, but by this point were on their last legs with constant breakdowns and a lack of spare parts. A replacement was required that shared the same qualities; mobility and firepower.
In the early 1980s, such a replacement was soon found in the shape of the compact, highly mobile and air-deployable light tank, the British FV101 Scorpion CVR(T). The Scorpion would be the first tracked vehicles purchased by the Defence Forces of Ireland (IDF. Irish: Fórsaí Cosanta, officially: Óglaigh na hÉireann) since those Comets some twenty years prior. They became the last tracked vehicles in operation, and also the last vehicles to be bought from Great Britain.

Scorpion in training on the Glen of Imaal. It is an earlier example, signified by the .50 Caliber machine gun mounted on the roof. Photo: Getty

The FV101 Scorpion

The officially named FV101 Scorpion Combat Reconnaissance Vehicle (Tracked) was designed by the Alvis Car and Engineering Company Ltd in the early 1960s. After a long trial period, the Scorpion entered service with the British Army in 1970. It was a three-man tank, with a crew consisting of a Driver, a Gunner, and a Commander.
Mobility was the Scorpion’s strong point. It was powered by the 4.2 litre, 6-cylinder, Jaguar J60 petrol engine. Usually, this engine produced 269 hp but was de-rated down to 198 hp for military use. This power plant could propel the tank to a top speed of 50 mph (80 km/h). This top speed allowed the tank to gain a Guinness world record for the fastest production tank (It was recorded doing 51.10 mph (82.23 km/h) at a test track on the 26th of January 2002). It used a ‘flat track’ suspension (track return supported by road wheels, as used on tanks such as the Soviet T-54) with five road-wheels. The idler wheel was at the rear while the drive sprocket was at the front.
For a small tank, the Scorpion’s armament was rather potent and consisted of the Royal Ordnance 76mm L23A1 Gun. This gun could fire a range of ammunition including HESH (High-Explosive Squash Head) and Canister. Secondary armament consisted of a coaxial 7.62 machine gun. Maximum armor thickness was 12.7 mm (0.5 in).
Although removed from service in the British Army in the late 1990s, the Scorpion and its variants remain in service across the globe. It can also be found in the arsenals of Bolivia, Indonesia, Chile, Thailand, and many others.

Irish Service

The Scorpion’s small size, good speed, and a relatively potent gun made it an attractive vehicle for the Irish Defence Forces’ Cavalry Corps. Subsequently, the Irish Military purchased a total of 14 of the tanks between March 1980 and December 1985. The numbers were thus: 4 in 1980, 4 in 1981, 4 in 1982, 2 in 1985.
The Scorpions were delivered in their standard British configuration armed with the 76mm L23A1 and equipped with wading gear that was soon removed. The 76mm gun proved to be somewhat of a problem as there was no fume extractor. When the gun was fired the turret compartment would fill with smoke and fumes. Should the gun be fired with turret closed down, the effect was even worse. One way the British and other armies dealt with this was by removing the 76mm turret and replacing it with the turret of the FV107 Scimitar armed with the 30mm Rarden Cannon. The Irish Military, on the other hand, wanted to keep the larger caliber 76mm. As such, they developed their own fume extraction system (FES) which kept the tank safe to operate.

Scorpions conducting a night shoot on the Glen of Imaal. Photo: IDF Archives
Scorpions assigned as Troop Commander’s tanks were originally equipped with a .50 Cal Browning M2HB heavy machine gun on a pintle mount upon the turret roof. These were later replaced with a 7.62 GPMG (General Purpose Machine Gun) as the .50 increased the silhouette of the Scorpion.
The Scorpions entered service with the 1st Tank Squadron in March 1980 and were used primarily in an armored reconnaissance role. This is the combination of infantry based recon with the support of armor. The FV101s remained part of this squadron until 1998, when the 1st Tank Squadron ceased to be a separate body, and became a part of the 1st Armored Cavalry Squadron (1 ACS). They were based at Curragh Camp, Kildare.
A standard camouflage pattern of black, brown and green was applied to the tanks, including the wheels in some cases. Unit markings were applied to the mantle on the right of 76mm barrel.
Over the course of their service, the Scorpions have taken part in many training exercises at the Glen of Imaal (Irish: Gleann Uí Mháil), in the Wicklow Mountains. 5,948 acres of the Glen has been used as an artillery and gunnery range since 1900. The vehicles also took part in a number of public and military parades.
In 2004, Seven Scorpion tanks were stationed as a ‘Guard of Honour’ at Shannon Airport, County Clare for a visit by the then serving US president, George W. Bush.

Irish FV101 Scorpion, showing the camo pattern that included coverage of the road wheels. Illustration by Tank Enyclopedia’s own AmazingAce, based on work by David Bocquelet.

Fate

The Scorpions stayed in service for 37 years, only being stood down in 2017. The role of the tank has largely been taken over by Ireland’s main armored vehicle, the wheeled 8×8 MOWAG Piranha IIIH, 80 of which have been in service since 2001.

Irish Scorpion taking part in a military display in June 2007, it is parked next to its successor, the Piranha III. Note the two-tone camo on the road wheels. Photo: Paul McMenamin

A Scorpion taking part in an Easter Sunday parade in 2016. Photo: William Murphy

An article by Mark Nash

FV-101 specifications
Dimensions (L-W-H)	15’7″ x 7’3″ x 6’9″ ft.in (4.79m x 2.23m x 2.10m)
Total weight, battle ready	8.07 tons (17 800 ibs)
Crew	3 (Driver, commander, gunner)
Propulsion	Cummins BTA 5.9-litre (diesel) 190 hp (140 kW) – pwr 22,9 hp/t
Suspension	Independant torsion bars
Speed (road)	45 mph (72,5 kph)
Range	470 mi (756 km)
Armament	Main : ROF 76mm L23A1 Sec. coaxial 7.62mm GPMG
Armor	12.7 mm front and sides (0.5 in)
Total purchased	14.

Links, Resources and Further Reading

www.curragh.info
www.historyireland.com
www.geocities.ws/irisharmoredvehicles
An Cosantóir, The Irish Defence Journal, March 1983 issue.
Tiger Lily Publications, Irish Army Orders of Battle 1923-2004, Adrian J. English
Irish Army Vehicles: Transport and Armour since 1922 by Karl Martin
Mushroom Model Publications, AFVs in Irish Service Since 1922, Ralph A. Riccio

WW2 German Flamethrowers

Flammpanzer 38(t)

German Reich (1944)
Flamethrower Tank – 20 Built

On the 27th of November 1944, Hitler ordered the construction of 20-30 Flammpanzers. The next day, he was shown how many of these could be built on the existing chassis of tanks or tank destroyers in the following days.
On the 3rd of December, it was reported that 35 such conversions could be produced. Ten of these would be Panzer IIIs that would be converted into the Flammpanzer III, also known as the Panzer III (fl) or (flamm). The other 25 would be made up of Jagdpanzer 38(t)s. The 20 vehicles that were built were obtained directly from the factory on the 8th of December 1944. After the conversion, they were known as the Flammpanzer 38(t).
The vehicle is known by two names. These consist of the simplistic “Flammpanzer 38(t)” and the rather more official “Panzerflammwagen 38(t) mit Koebe-Gerät”

One of the Flammpanzers captured by US forces. A GI stands to the right of the vehicle. Photo: Osprey Publishing

The Jagdpanzer 38(t)

The Jagdpanzer 38(t) was based on the chassis of the Panzer 38(t) light tank, which, in turn, was based on the Czech LT vz 38. It is controversially known as the ‘Hetzer’. The running gear and engine was unchanged (aside from strengthened road-wheels), with the Jagdpanzer’s 15.75 tonne weight supported on four road wheels attached to a leaf-spring suspension. Propulsion was provided by a 158hp Praga 6-cylinder petrol engine.
An armored casemate was added in place of the turret and main body of the tank. The chassis was also widened. For a small vehicle, the armor and armament were very effective. Frontal armor consisted of a large plate which was 60mm (2.36in) thick and sloped at 60 degrees from the vertical, which, therefore, offered around 120 mm (4.72 in) of effective protection. This was also where the main armament, the potent 7.5cm PaK 39 L/48 was mounted.

Design of the Flammpanzer

Not too many changes were necessary to turn the tank destroyer into a flamethrower. The biggest modification came with the removal of the 7.5cm gun and accompanying cradle with traverse and elevation gears, as well as the 7.5cm ammunition storage racks.

A flammpanzer that was abandoned after action. The protective barrel around the flame projector is broken. A common complaint from crews was that this sheath was far too fragile. Photo: Osprey Publishing
A “Koebe-Gerat” (Lit. ‘device designed by Koebe’) 14mm Flammenwerfer (flamethrower) was placed in the void left by the gun on a swivel mount, with limited traverse and elevation angles. The flamethrower was aimed by a periscope which was added directly above the flame gun, atop the bulbous armor of the mantlet. It was the same model as the one used on the Sd.Kfz.251/16, a flamethrower version of the famous half-track. Like the other Flammpanzers, the nozzle of the flammenwerfer was protected by a false 120mm diameter false gun barrel. Firing unlit flame oil, a maximum range of 50 meters could be reached. When firing ignited oil, which was ignited by a blank cartridge (known as ‘Zuendpatrone’), the range increased to 60 meters. Unlit fuel was often projected to saturate a target area before it was ignited by a proceeding ignited burst. A 700-liter tank carried enough fuel for 60 to 70 one-second bursts of flame at a rate of 10 liters per-second
Unlike most flamethrowing versions of existing gun tanks that usually drop the loader crew member, the 38(t) retained a 4-man crew. This consisted of the Flamethrower Operator, Radio Operator, Commander, and the Driver. The original plan for the vehicle, however, was for it to have a three-man crew, with the Commander also doubling as Radio operator.

Flammpanzer 38(t), 352nd Panzer-Flamm-Kompanie, Army Group G, Belgium, December 1944. Illustration by Tank Encyclopedia’s own David Bocquelet

Action

Initially, the Flammpanzers were to be used as part Operation Northwind (Unternehmen Nordwind), the last major offensive of German forces during the Second World War, which would start on New Years Eve 1944. Earlier that December, Heeres Gruppe G had reported 2 Flamm-Panzer-Kompanien, each with 10 Flammpanzer 38(t)s ready for action. These were Panzer-Flamm-Kompanie 352 and Panzer-Flamm-Kompane 353. Kompanie 352 were ordered to the front Christmas Day, with Kompanie 353 following on the 30th. It appears that both Kompanien, however, did not take part in the operation.
The first combat report of the Flammpanzer 38(t) was not recorded until mid-February 1945. Kompanie 352 and 353, attached to Panzer-Abteilung 5, 25. Panzer-Grenadier-Division took part in combat during an attack on Hatten, a French village near the border with Germany. The action was costly to Kompanie 353, which lost seven of their Flammpanzers and all of their officers. As such, the remainder of the 353rd was absorbed into the 352nd.
In this action, the 13 remaining Flammpanzers were used to counter Allied bunkers and dug in gun positions. A number of times while assaulting positions in Hatten, the vehicles broke operating procedure and attacked without infantry or gun tank escort. This was strictly forbidden in the case of flame tanks.
Street fighting in the nearby village of Rittershoffen would be the next action for the Flammpanzers. Three vehicles were lost in this action, two to anti-tank and tank gunfire, and the other lost to a mine. An attempt at recovery was made, but it was damaged beyond repair during a further barrage of Allied fire. By March 1945, Kompanie 352 reported that they still had at least 9 Flammpanzer 38(t), 8 of which remained operational.

An American soldier stands beside a captured Flammpanzer. Photo: Osprey Publishing

Descendant

This Flammpanzer was not the only flamethrowing tank built on the chassis of the LT .vz 38/Panzer 38(t) light tank. In 1949, the Czechs designed and prototyped the PM-1. The flamethrower gun was placed in a turret that was mounted on the Jagdpanzer’s roof. A large tank for fuel was added to the rear. Only three prototypes of this tank were built, with the project ending in 1956.

Flammpanzer 38(t) specifications
Dimensions (L W H)	4.83m (without gun) x 2.59m x 1.87 m (15’10” x 8’6″ x 6’1″ ft.in)
Total weight, battle ready	15.75 metric tonnes (34,722 lbs)
Armament	14 mm Flammenwerfer 7.92 mm (0.31 in) MG 34, 1,200 rounds
Armor	8 to 60 mm (0.3 – 2.36 in)
Crew	4 (driver, commander, gunner, loader)
Propulsion	Praga 6-cyl gas. 160 hp@2,800 rpm (118 kW), 10 hp/t
Speed	42 km/h (26 mph)
Suspension	Leaf springs
Range	177 km (110 mi), 320 l
Total production	10

Links, Resources & Further Reading

Osprey Publishing, New Vanguard #15: Flammpanzer German Flamethrowers 1941-45
www.historyofwar.org

Cold War Austrian Tech Cold War French Tech Cold War Swedish Tech Cold War US Tech WW2 German Tech

Oscillating Turrets

Oscillating turrets were one of the latest trends in tank design in the early years of the Cold War, in the 1950s. The original intention of this type of turret was to make it easier to employ an automatic gun loader in the turret of a tank.
As well as the ability to fit an autoloader, there were other benefits. These included the ability to mount a big gun on a small chassis, have fewer crew members by the omission of the Loader crew member, and have a smaller turret. It also generally allows for a better front profile ballistically.

An AMX-13 90. The AMX-13s is perhaps the most famous and most successful tanks to use oscillating turrets. Photo: The Modeling News.

Design

Oscillating turrets consist of two parts that move on a separate axis. These are the top ‘roof’ section which holds the rigidly mounted main armament which moves up and down. In a conventional turret, the gun moves separately from the turret body, on its own trunnions.
The bottom ‘collar’ part is attached to the ‘roof’ via pivot joints and is fixed directly to the turret ring, allowing conventional 360-degree traverse.

History

Though it seems a relatively modern idea, the oscillating turret design actually goes back as far as the First World War, to a designer by the name of Arnold H. S. Landor. Landor, a British inventor living in Italy, who designed a new armored car in 1915. It featured possibly the first ever oscillating turret, which was armed with 65 or 75mm gun (specifics unknown) mounted on the vehicle’s roof. This was closely followed by an Armored car designed by Joseph Gonsior, Friedrich Opp, and William Frank. A joint project between the USA and Austro-Hungary from 1916, it had a machine gun in an oscillating turret. The elevation/depression was controlled via hand-cranks.
The next time such a component would appear would be in the early 1940s on the French armored car prototype, the Panhard 201. After the German invasion of France, the prototype was evacuated to northern Africa. This armored car was topped off with an oscillating turret that was manually operated and armed with an SA35 25mm gun.

The Panhard 201 with a simple oscillating turret. Photo: SOURCE
Late in the in the Second World War, the turret type was used again, this time as part of the German prototype Self-Propelled Anti-Aircraft Gun, the Flakpanzer IV Kugelblitz. This prototype was named after its turret; the name translates to “Lightning Ball”. It consisted of an armored ball mounted on an armored collar connected to the turret ring. The ball, mounting dual 30mm MK 103 cannons, moved independently in elevation, allowing it to target aircraft.
Post Second World War and during the early stages of the Cold War, the French began to lead the way in the development of this type of turret. They invested a great deal of time and money in designing such turrets for light tanks like the AMX-13 and armored cars such as the Panhard EBR (descendant of the 201). The French became the leaders in this technology and was the first (also one of the few) nation to employ this type of turret on a vehicle that saw active service.
Though they were never used on a serial production vehicle, the United States of America also began experimenting with oscillating turret designs in the late 1950s. Such turrets were developed for Light, Medium, and Heavy Tanks. Several prototypes were built to test these turrets, but they were never adopted. This was largely due to the fact that the Americans found no real advantage in using these turrets over the conventional format.

A scale model of the Kugelblitz produced by the designers. Photo: panzernet.net

Advantages

The major advantage of this type of turret was that it made the addition of an autoloader far easier becasue the loading system moves with the gun. In a conventional, rotating turret, an autoloader would have to follow the gun in elevation and depression to align the shell with the breech, and then ram it in. This method was used in the T37, an experimental American light tank. In other cases, such as with the Soviet IS-7 heavy tank, the gun had to be brought back to a neutral elevation after every shot, making engaging a target with multiple shots much slower. This is called the ‘index position’ and its an issue that remains to this day.
Oscillating turrets eliminated the hassle of both of these methods. As the gun was rigidly placed in the upper part of the turret, the autoloader, attached to the upper ‘roof’ section was free to ram shells in whatever the elevation angle the gun. Not only does this system speed up reloading but it allows the gun to stay on target during reloading which improves the speed of second and subsequent shots on target.
In a conventional turret, the breech of the gun sinks into the basket when elevated, meaning that the turret ring has to be of large enough diameter to accommodate this motion. With an oscillating design, the breach remains above the turret ring whatever the angle, meaning that the turret ring can be smaller, ergo, the hull can be smaller allowing for a bigger gun proportionally on a smaller vehicle. However, in this case, the maximum elevation angle is defined by the space between the rear of the turret and the deck of the hull, which may be less than the angles possible in a conventional design where the breach can fall into the hull.

Disadvantages

In this type of turret, the gun is often mounted high-up to grant as much room for elevation and depression as possible. Angles of fire though, were still rather limited when compared to traditional gun mounts. In elevation, the turret bustle would often be mere inches above the engine deck. Mounting the gun high in the turret gives a larger silhouette and easier to spot at distance than the lower-profile conventional turret. This is somewhat offset, however, due to the fact that in a hull-down position less of the turret would be exposed due the height of the gun mount and the improved ballistic shape of the turret
One of the biggest issues with oscillating turrets is that they could not be made safe against NBC (Nuclear, Biological, Chemical) attacks. Due to the to their design, there was a gap between the two moving sections of the turret. This was usually covered by waterproof canvas or rubber bellows that shrank and extended with the motion of the turret, but it was not an air-tight seal.

Outcome

The complexity of their design was the downfall of the oscillating turret, with most work on such designs coming to an end in the mid-1980s. To most military bodies, the opinion was shared that the turrets provided ‘no real advantage’ over the traditional format.
Autoloader technology had improved to the point of being compatible with a regular gun and turret layouts, removing the need for such turrets and the disadvantage of not being able to be sealed against NBC had remained a major and unresolved problem.
In 2013, however, a new vehicle with an oscillating turret entered service with the US Military. This is the M1128 Mobile Gun System (MGS). It consists of an unmanned, remote-controlled turret on the hull of the Stryker ICV (Infantry Combat Vehicle). The vehicle is armed with a 105mm M68A2 rifled gun, and is fed by an 8-round autoloader. It is currently one of the only vehicles with an Oscillating turret serving in an active Military.

The M1128 MGS with turret eleveated. Photo: WBS

French AMX-13 75.

Austrian SK-105 Kürassier

American 90mm Gun Tank T69

American Stryker based M1128 Mobile Gun System
Illustrations by Tank Encyclopedia’s own David Bocquelet

Tanks & AFVs with Oscillating Turrets

France

Panhard EBR: Armored car. In 1940, one of the pilot vehicles, the Panhard 201, was used in testing one of the earliest examples of an oscillating turret. Later models shared turret types and weaponry with the AMX-13. 1954, in service in France until 1981
AMX-13: A series of light tanks. Started out with a cylindrical oscillating turret with non-autoloading 75mm. This progressed to a longer, squarer turret with an autoloading system known as the FL-10. It is perhaps the most successful type of oscillating turret. Armaments progressed from a 75mm gun, to a 90mm and finally a 105mm gun. Entered service in 1952, in service with France until the 1970s, also in the arsenal of countries like Israel, Mexico and Singapore. Singapore only began to retire the tank in 2012.
Char Leger De 12 Tons: Competing design for a light tank, utilising a similar (if not the same) turret as the AMX-13. The major difference was with the running gear based on the classic German interleaved design. Early 1950s, no serial production.
AMX ELC EVEN series: A series of light tanks with various weapons including 30mm, 90mm and 120mm guns. The oscillating turret , consisted of a flat upper part on top of a ‘neck’ joint which was protected behind a truncated material cover. The weapons were often mounted off the center line at the extreme right or left of the turret. 1955, no serial production.
Batignolles-Châtillon Char 25t: Medium tank prototype designed along the same lines as the AMX-13s. It was armed with a 90mm gun and auto-loader. 1954, no serial production.
Lorraine 40t: Medium tank prototype with a unique suspension consisting of pneumatic road-wheels. It was armed with a powerful 100mm gun and autoloader. 1952, no serial production
AMX-50: A series of heavy tank prototypes. The earliest version borrowed much from the Lorraine 40t using a similar turret and the same 100mm gun and autoloading system. The later version incorporated a newer, larger turret design similar to that of the AMX-13’s known as the ‘Tourelle D’ and was armed with a 120mm gun. The AMX-50s borrowed the German style suspension with interleaved road-wheels. Early 1950s, no serial production.
Somua SM: A heavy tank design that competed with the AMX-50. It featured the same turret as the early AMX-50 prototype, armed with a 100mm gun fed by an autoloader. The hull design was heavily inspired by the Tiger II, but used a different individual wheel suspension instead of the famous interleaved type. Early 1950s, no serial production
Medium Tank M4 with FL-10: A number of surplus Sherman tanks were updated by adding the AMX-13’s 75mm armed FL-10 turret. Various models of Sherman were updated, including M4A1s and M4A2s. M4A2s with the turret were used by the Egyptian army in the Six-Day War. Mid-1950s, limited production.
Light Tank M24 with FL-10: A project to modernize M24s in France’s inventory by replacing the standard turret with the 75mm armed FL-10 of the AMX-13. 1956, no serial production

United States of America

Gonsior, Opp, and Frank War Automobile: A joint armored car project designed by Joseph Gonsior, Friedrich Opp, and William Frank. A joint project between the USA and Austro-Hungary from 1916, it had a machine gun in an oscillating turret. The elevation/depression was controlled via hand-cranks. Never left blueprint stages. 1916, no serial production.
76mm Gun Tank T71: A light tank design by two competitors. These were Detroit Arsenal (DA) and Cadillac Motor Car Division (CMCD). DA’s design utilised an oscillating turret and autoloader feeding a 76mm gun. The vehicle was never built and never left blueprint stages. Early-1950s, no serial production
90mm Gun Tank T69: Medium Tank prototype with an oscillating turret mounted on the hull of the failed T42 medium tank project. The turret contained an 8-shot cylinder, not unlike a giant version of one you would find on a handgun. Only one was ever built as the turret was not thought to provide “any real advantage” over the traditional type. Mid-1950s, no serial production.
105mm Gun Tank T54E1: Medium tank prototype produced for series of trials to find the best way to mount a 105mm gun on the hull of the M48 Patton III. An autoloader system was also utilised inside the turret. Mid-1950s, no serial production.
155mm Gun Tank T58: A heavy tank design utilising an oscillating turret with autoloader, mounted on the hull of the T43/M103 hull. Had the tank left the drawing board, it would’ve been armed with a 155mm gun, the largest gun to be mounted in an oscillating turret. Mid-1950s, no serial production.
120mm Gun Tank T57: A heavy tank design similar to the T58 but armed instead with a 120mm gun. Mid-1950s, no serial production.
120mm Gun Tank T77: A heavy tank project to mounting the T57’s turret on the hull of the M48 Patton III. Mid-1950s, no serial production.
M1128 Mobile Gun System: The latest American vehicle to use this turret type. It consists of an unmanned, remote turret on the hull of the Stryker ICV (Infantry Combat Vehicle). The vehicle is armed with a 105mm M68A2 rifled gun, and is fed by an 8-round autoloader. 2013, currently serving.

Austria

SK-105 Kürassier: Austrian light tank. The hull was an indigenous design, but it utilized the turret of the AMX-13 bought from France. They were armed with 105mm guns. Early 1970s, in service with Austria until the 1990s, remains in service countries such as Argentina and Botswana.

Sweden

EMIL Project: A series of heavy tank designs with heavily armored oscillating turrets. They were designed with autoloaders and guns from 105mm to 150mm. Two chassis, codenamed “Kranvagn” (English: Crane vehicle) were constructed before the project’s cancellation. Early 1950s, no serial production.
Strv m/42-57 Alt. A.2.
In an effort to up-gun their already vastly outdated Stridsvagn m/42. A meeting was held on February 15th, 1952 on possible improvements. One solution was to mount a new oscillating turret design on to the m/42’s hull. This idea never came to fruition, however.

Germany

Flakpanzer IV Kugelblitz: Anti-aircraft tank built on the chassis of the Panzer IV. The tank was named after its turret, the name meaning “Ball Lightning”. It was armed with two 30mm MK 103 auto-cannons. 1943, no serial production.
DF 105 Combat Tank: A cooperative project between France and Germany combining the Marder I chassis with an updated AMX-13 turret with a 105 mm main gun. It was called the DF 105 Combat Tank. Early-mid 1980s, not serialized. Mid-1980s, no serial production.
CLOVIS, FL-20, 105mm: A follow up project of the DF 105. The Marder chassis remained the basis, but a completely new oscillating turret was added. It was possibly one of the last turrets of the type to be developed. 1985, no serial production.

Great Britain

COBRA: A design for a 30-ton tank to carrying a 120mm gun. It was extremely lightweight for a tank with such a gun, but retained excellent armor protection over the entire frontal arc. Side and rear armor were sacrificed, however. 1954, no serial production.

Italy

AMX-13/60: An update program that replaced the existing gun of the French Light Tanks with a high-velocity 60mm gun.

Links, Resources & Further Reading

www.chars-francais.net
www.armchairgeneral.com
Panzer Tracts issue 12–1: Flakpanzerkampfwagen IV and other Flakpanzer projects development and production from 1942 to 1945, Thomas Jentz & Hilary L. Doyle.
Presidio Press, Patton: A History of the American Main Battle Tank, Volume 1, R. P. Hunnicutt
Presidio Press, Firepower: A History of the American Heavy Tank, R. P. Hunnicutt
Rock Publications, the AMX-13 Light Tank. Volume 2: Turret, Peter Lau
The Tank Museum, Bovington, UK
The National Armor and Cavalry Museum (NACM), USA
Musée des Blindés, Saumur, France

WW2 German Improvised Vehicles WW2 Soviet Vehicles in Foreign Service

Panzerkampfwagen KV-1B 756(r) (KV-1 with 7.5cm KwK 40)

Post author By Mark Nash
Post date April 20, 2018
17 Comments on Panzerkampfwagen KV-1B 756(r) (KV-1 with 7.5cm KwK 40)

German Reich (1942-1943)
Heavy Tank – 1 Converted

Throughout the Second World War, the German Army captured hundreds of tanks and armored vehicles from countries it invaded. The same was true during the invasion of the Soviet Union. The Germans frequently made upgrades and modifications to fit their needs. This process spawned one of the larger armored vehicle enigmas to come out of the War.
This was the KV-1 that was captured and then re-armed with the 7.5cm KwK 40 gun. Not much is known about the history of this improvisation, and there is only one known photo to prove its existence.
It is not the only tank of the Second World War that was retrofitted in the field to accept a gun from another nation. Other examples include the Churchill NA 75 which was a British Churchill tank modified to accept the American 75mm Tank Gun and the Matilda II that was modified to accept the 76mm ZiS-5 gun. In both of these cases, of course, they were not captured vehicles.

The only known image of the modified KV-1.

Background, the KV-1

The KV-1 was the unsuspecting winner of a Soviet contract for a new heavy tank to replace the obsolete T-35A Multi Turreted Heavy Tank. The KV tank beat the SMK and T-100 to make it to mass production. Immediately prior to the invasion of the USSR in June 1941, roughly 508 KV-1 tanks were in Red Army service.
The KV-1 was an unpleasant surprise to the advancing Germans in June 1941, due to its excellent armor protection. The KV-1 quickly gained a fearsome reputation on the battlefield, being able to withstand point-blank shots from the standard 37mm anti tank guns fielded by Germany. Many KV-1s returned from combat peppered with dents and gouges from ricochets which had failed to penetrate its armor. However, the KV-1s made little impact on the actual fighting during the months of Operation Barbarossa with the exception of a small number of engagements. Poor crew training, poor logistical support and inept command and control meant that the Soviet tanks, including the mighty KV-1, where deployed in small packets that were easily swallowed and terminated by the better organized German units.
The KV-1 tank weighed 45 tonnes, and was powered by the 660hp V2K engine. The suspension was the first Soviet use of torsion bars, and it consisted of six road wheels, a rear drive wheel, a large front idler wheel and three return rollers. The tank had a crew of five. Soviet engineers constantly updated the tank and, between 1941 and 1942, the armor was thickened from 90mm to 200mm in places. The firepower was improved too, from the 30.2 calibre long F-32 76.2mm gun, to the 42.5 calibre long 76.2mm Zis-5 gun. The F-32 gun could penetrate 50mm of armor at 1,000m, whereas the Zis-5 gun could penetrate 60mm of armor at the same range. In 1942, this made the gun a significant threat to most German tanks. However, the gun was similar to the one on the T-34 medium tank, which was far more mobile and far cheaper to build.

KVs in German Service

When the Wehrmacht first encountered the KV-1, they were horrified and greatly impressed with its capability to take extreme punishment from the main German tank and anti-tank guns of the time. Contrary to popular belief, there were only a handful of KV-1 tanks that were ever pressed into German service. The captured tanks were known as ‘Beutepanzer’ or trophy tanks.
In 1941, the Germans had a categorizing system for those units captured from the enemy, this was an “Ebeuten” number. The number for KV tanks of all sub-types was “E I”. The overwhelming majority of these tanks were either dismantled at the roadside, or returned to the Reich for museums or testing. However, there were some KV tanks pressed into Wehrmacht service.

Beutepanzer KV-1 ‘1’ of the of the 8th Panzer Division. Photo: SOURCE
The earliest known Beutepanzer KV-1s, which in the German numbering system were known as the Pz.Kpfw KV-1A 753(r) (r = Russia) were deployed in the Autumn of 1941. German changes were minimal, with most Beutepanzer KV-1s retaining the original Soviet radio and equipment, however, occasionally German radios and tool sets were issued. The most interesting German acquisitions were the two OKV-1 tanks pressed into service. The Kirov works in Leningrad had manufactured six prototype flame throwing KV tanks, with a flame unit in the hull. All were used in combat, and two were subsequently pressed into Wehrmacht service after their capture.
Between 1941 and 1943, the German army likely dealt with thousands of lost KV tanks, of which perhaps several hundred were captured in working condition. It is thought however that less than 50 KV-1 tanks were pressed into German service. A multitude of factors can explain this, from lack of spare parts, to German overconfidence in their own tanks, to the Nazi ideological doctrine that viewed anything manufactured by a Slavic race to be inferior.

German Modification

The specific model of KV-1 that this conversion was based upon was a 1942 model, manufactured at Factory 100 Chelyabinsk (ChTZ) and was probably manufactured in the first or second quarter of 1942. It was fitted with the applique armor on the nose, and on the glacis plate which increased the armor up to 200mm (7.9 in) thick in places. It was equipped with the lightweight cast turret. Sometimes, this model also carried a heavyweight cast, or simplified welded turret. Standard armament remained the same, being the 76mm ZiS-5 gun. In German service, this was designated as the Pz.Kpfw KV-1B 755(r). This modified version was designated Pz.Kpfw KV-1B 756(r). The construction work was carried out by the maintenance battalion of Panzer Regiment 204 of the 22nd Panzer Division.

Gun

The most drastic modification to this single KV was the alteration made to the main armament. The original Soviet 76mm ZiS-5 gun was removed to make way for the German’s own 7.5cm KwK 40 L/43.

Diagram of the L/43 gun in its standard mounting, the Panzer IV
This gun was derived from the 7.5cm PaK 40, a towed anti-tank gun that entered service in 1942. In 1942-43, the gun was also mounted on Germany’s main medium tank, the Panzerkampfwagen IV, replacing the short barreled 7.5cm KwK 37 howitzer. Tanks with this new armament were designated as the Panzer IV Ausf.F2. It was a deadly weapon, with a range of ammunition types. These included Armour Piercing Capped Ballistic Cap (APCBC), Armor-Piercing Composite Rigid (APCR) and High-Explosive Anti-Tank (HEAT). The APCBC was its most deadly round, able to penetrate a maximum of 99mm (3.9 in) of armor.
At this time, the 7.5cm KwK L/43 was a rare gun, as only 135 Panzers were equipped with it. One these tanks must have been irreparably damaged in action, but retained an operable gun that was able to be cannibalized. Though the ZiS gun was removed, the mantlet was retained. The new gun was posted through the void breach first and mounted into position, complete with its coaxial MG 34 machine gun. It is unknown as to what internal modifications took place concerning the placement of the trunnions and elevation/depression gears. Being the more powerful gun, the KwK 40 was larger in the breach than the ZiS. The 7.5cm shell was 100mm longer than the 76mm shell of the ZiS, meaning the breach was also 100mm longer. Recoil length would also have been longer, meaning there was even less room behind the gun.

Turret Changes

Minor modifications were also made to the turret. A salvaged commander’s cupola from either a Panzer III or Panzer IV (It is unclear which one it is) was added atop the turret. This was not added over the original commander’s hatch at the rear of the turret. A new hole was cut in the roof towards the right front of the turret, and the cupola added above it. This cupola gave the commander far better visibility, allowing him to spot targets, navigate terrain and observe friendly units easier.
On the left, an air filter was added, with a cover salvaged from a T-34.

But, Why?

A great deal of time was spent theorizing this matter by both authors of this article. The conversion of just this one vehicle would have been time and resource consuming. Other vehicles that were modified in such a way, such as the Churchill NA 75 and Matilda II with ZiS-5 which are mentioned in the introduction, had a designed purpose. The idea behind the Churchill NA 75 was to make use of guns from wrecked tanks, and give the poorly armed Churchill more Anti-Armor and High-Explosive firepower. The same was true for the Matilda, the original 2-Pounder gun of which was considered useless by the Soviets.
This KV, however, seems to lack any recorded intention. The German 7.5cm KwK 40 was a much better gun than the Soviet ZiS-5 76mm. At 1000 meters, the ZiS could only penetrate 61mm of armor, at the same distance, the 7.5cm could punch through 82mm. Ammunition may also have been a factor, as it would’ve been far easier for the Germans to resupply with 7.5cm ammunition than 76mm ammunition.
These are the only practical advantages of adding this gun to the KV. The KV, at this time, was one of the best heavy tanks in the war, and as already discussed, the Germans already had a number of captured examples in their arsenal. It may be that this was intended as somewhat of an ‘Anti-KV’ or ‘Anti-T-34’ vehicle. The Soviets’ own 76mm Gun could not penetrate the front of a standard KV-1 (without 200mm armor) or T-34 at 1000m. The German 7.5cm could handle both. Putting this gun on a chassis the 76mm could not penetrate would prove deadly to any Soviet vehicle facing it.
There is, however, an element of redundancy in the project worth highlighting. At the time this vehicle was built, German vehicles such as the Panzer IV (with long 75mm), Panzer V Panther, Panzer VI Tiger, and Panzerjager Tiger (P) were appearing. All of these, while still teething, were adequately armed so that the armor on the T-34 and KV-1 did not provide the advantage they had. With the 8.8cm gun or high velocity 7.5cm gun both the T34 and KV-1 were much more vulnerable.
The most logical conclusion as to why this KV was modified in this way is therefore that it was simply a culmination of spare parts and ingenuity.
This KV was apparently active at Kursk, but further details of this are scarce.

An article by Mark Nash and Frankie Pulham

Specifications
Dimensions (L-w-h)	5.8 x 4.2 x 2.32 m (19.2×13.78×7.61 ft)
Total weight, battle ready	45 tonnes
Crew	4 (commander, driver, 2 gunners)
Propulsion	V12 diesel V2, 600 bhp (400 kW)
Maximum Speed	38 km/h (26 mph)
Range (road/off road)	200 km (140 mi)
Armament	7.5cm KwK 40 L/43 2x DT 7.62 mm machine-guns 1x MG 34 7.92mm machine gun
Armor	30 to 100 mm (1.18-3.93 in)
Total Convered	1

Links, Resources & Further Reading

Panzer Tracts No.19-2 – Beutepanzer – British, American, Russian and Italian Tanks Captured From 1940 to 1945, Thomas L. Jentz & Werner Regenberg
Osprey Publishing, New Vanguard #17: KV-1 & 2 Heavy Tanks 1939-45
Frontline Illustrated, History of the KV Tank, Part 1, 1939-1941, M Kolomiets.
beutepanzer.ru

The Panzerkampfwagen KV-1B 756(r) with added 7.5cm KwK 40. Illustrated by Tank Enyclopedia’s own David Bocquelet.

Cold War US Heavy Tank Prototypes

155mm Gun Tank T58

United States of America (1952)
Heavy Tank – 2 Turrets Built

In the early 1950s, the American military’s quest for a powerful new heavy tank was well underway. The T28, T29, T30, T32, and T34 projects had all ceased in favor of the 120mm Gun Tank T43, which eventually became America’s last heavy tank, the M103.
While still in development as the T43, however, there were parallel projects competing for the role of America’s next heavy tank. One of these projects was the 120mm Gun Tank T57. It used the same hull as the T43, but incorporated new technologies for the turret. The turret was of the oscillating kind, but it was also outfitted with an autoloading mechanism.
In the Army Development Guide of December 1950, both the T43 and T57 were expected to more than meet the requirements of the military and be a worthy adversary of Soviet armor such as the infamous IS-3. However, in the Tripartite Conference of Armor and Bridging of October in 1951, it was recommended that a 155mm gun armed tank be developed instead.

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

Development

A list of recommended characteristics for this new heavy tank was outlined in a paper on the 18th of January 1952. Such recommendations included a gun that exclusively fired HEAT (High-Explosive Anti-Tank) or HEP (High-Explosive, Plastic. Otherwise known as HESH – High-Explosive Squash Head) rounds. This paper also recommended the construction of two prototype turrets complete with autoloaders and 155mm guns for installation on T43E1 chassis. The resulting vehicle received the designation of 155mm Gun Tank T58.
On the 10th of April 1952, a contract was drawn up with United Shoe Machinery Corporation of Beverly, Massachusetts for the design, development and manufacture of the two pilot turrets.

Hull

The hull that was used for the project was the same as that of the 120mm Gun Tank T43, which would later be serialized as the M103, America’s last heavy tank. Armor on the hull was the same. The cast ‘beak’ was 3.9 – 5.1 in (100 to 130 mm) thick.
An 810hp Continental AV1790 12-cylinder air-cooled gasoline engine propelled this chassis to a speed of around 21 mph (34 km/h). The tank’s weight was supported on seven road wheels attached to torsion bar suspension. The drive sprocket was at the rear while the idler wheel was at the front. The idler wheel was of the compensating type, meaning it was attached to the closest roadwheel by an actuating arm. When the roadwheel reacts to terrain the idler is pushed out or pulled in, keeping constant track tension. The return of the track was supported by six rollers.

Turret

The T58’s turret was one of the largest oscillating turrets ever designed, at approximately ¾ the length of the hull. Changes had to be made to the T43/M103 hull to accommodate the new large turret. When initially tested on one of the hulls, the turret bustle would collide with the mufflers of the main engine and auxiliary generator located on the engine deck. To fix this issue, the mufflers were relocated 20-inches (51cm) to the rear. A new travel lock was added to the deck to accommodate the larger gun.
This turret had similarities to the T69 medium tank prototype, in that its roof had multiples ways of ingress and egress. The turret roof was constructed from two removable plates. The rear plate was bolted in place, while the front section, like the T69, was hinged and could be opened outward by use of a hydraulic piston. The large opening made it easier to exit the turret in an emergency. In the open position, this opened section also provided a shield for the crew while evacuating. These sections were designed to be easily removed to permit installation of the autoloader mechanism and other components.
A ventilator was placed at the rear-right of the turret atop the bustle to vent gases and smoke produced when the gun is fired.

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

Links, Resources & Further Reading

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

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

Armament

Originally, it was planned to utilize the 155mm Gun T80. This proved unnecessary as the chosen ammunition for the gun was of the chemical type and did not require the high-velocity granted by the T80. Designers instead opted for a lighter weight version of the lower velocity 155mm Gun T7, the gun developed for the Heavy Tank T30. Firing HEAT through this gun, the maximum armor that could be penetrated (angled at 0 degrees) was 16 inches (406mm).
This modified version of the T7 was originally designated as the 155mm Gun Howitzer T7E2. It was later changed, however, to ‘155mm Gun Howitzer T180’. There was no actual change to the gun, just a change in nomenclature. The T180 differed greatly from the original T7 though. The breech block was changed from a horizontal to a vertically sliding type. A bore evacuator (fume extractor) was added towards the end of the gun, and a T-shaped blast deflector installed on the muzzle. The gun tube wall was thickened and the chamber lengthened about an inch (~25mm) to accommodate the plastic closing plugs used on the cartridge cases of the two-part ammunition.
Unlike the T57 that had a rigidly mounted gun, the T58 was outfitted with a four-cylinder hydro spring recoil system in a mount designated the T170. There were 2 springs to each side of the breach. To save space and remove the need of extending the length of the turret, the recoil of the gun was limited at 12 to 14 inches.
Secondary armament consisted of a coaxial .30 Cal (7.62mm) Browning machine gun, and a .50 cal (12.7mm) Browning heavy machine gun mounted atop the commander’s cupola. The oscillating turret provided an elevation of 15 degrees, with a depression of 8 degrees. The original specifications included a second coaxial machine gun, but this was not included.
The main gun was aimed via periscopic sights. There was one lens on each side of the turret, known as ‘frog’s eyes’. These types of sights were used on many American tanks from the early 1950s onwards, including such tanks as the T69, M48 and M60.
The armor on both the collar and upper part the turret was extremely thick, but exact measurements are unfortunately unknown.

Autoloader

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

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

Crew

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

Fate

Work on two pilot turrets continued into 1956 despite numerous design changes during production and delays in obtaining and producing various parts required for assembly. By this time, however, trends had shifted, and a tank such as the T58 was no longer thought a necessary to the military.
The T58 project, along with the T57 and many other projects, was canceled on the 17th of January 1957. Following this outcome, both pilot turrets were scrapped. All that survives today are a few photos and government reports.

An article by Mark Nash

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

Illustration of the 155mm Gun Tank T58 by Tank Encyclopedia’s own David Bocquelet.

WW2 British Medium Tanks WW2 Irish Armor

Vickers Medium Mk.D

United Kingdom/Irish Free State (1929)
Medium Tank – 1 Built

Ireland’s First Tank

The British company of Vickers was one of the biggest tank producers in the years leading up to the Second World War. In 1925, the company began production of their Medium Tank Mk.II and the Irish Free State (today the Republic of Ireland) were interested in purchasing a similar tank.
In 1929, Vickers built the Medium Mk.D, a derivative of the Mk.II built solely for the Irish Defence Force (IDF. Irish: Fórsaí Cosanta, officially: Óglaigh na hÉireann). Only one of these tanks was ever produced. It would be Ireland’s first tank and was adopted by the 2nd Cavalry Squadron of the Irish Cavalry Corps (Irish: An Cór Marcra).

A Cavalry Man sits atop the turret of the Mk.D. The Commander’s hatch is open behind him. Photo: Irish National Archives

Design

The Mk.D was almost identical to the Mk.C which was sold to Imperial Japan in 1927. Any differences between the two models are not very well documented, but it seems the only major difference with the Mk.D was the addition of a cupola above the commander’s position in the turret.
What we do know is that the Mk.D was an upgrade of the standard Mk.II. It had a more conventional design, with the engine relocated to the back of the vehicle. The engine in this new compartment was more powerful than previous models. This engine was a water cooled, 6-cylinder Sunbeam Amazon petrol engine, rated at 170 bhp. This engine gave the tank a top speed of 20 mph (31 km/h).
The tank was of bolted construction, but the exact thickness of the armor is unknown. It would not be too far-fetched to assume it had similar armor properties to the Vickers Mk.II, which had armor of up to 8mm (0.31 in) thick. Other upgrades incorporated on the Mk.D and C for that matter included a slight elongation of the suspension and improved mud-chutes. The suspension consisted of 6 pairs of double-wheel bogies connected to coil springs. There was also a single track-tension idler wheel (jockey-wheel to Americans) on a single coil-spring in between the leading bogie and idler wheel at the front of the tank. There were 4 track return rollers and the drive wheel was at the rear.

Troops are instructed on the operation of the tank’s powerplant. The turret is traversed backward. Note the missing 6-Pounder gun which would otherwise be pointing over the engine deck. Photo: MMP
Armament was also different from previous models. The main armament consisted of a low-velocity 6-Pounder gun designed to fire High-Explosive shells in an infantry support role. This was in contrast to the higher velocity 3-Pounder guns being used on other British Vickers tanks. It was also armed with no-less than four Vickers water-cooled .303 machine guns. Two of these were located on the vehicle’s flanks. There was also one mounted in the turret bustle and another one on the left of the upper glacis.
The Mk.D had a crew of 5. This was composed of the Commander, Gunner, Loader, and Driver. The role of the fifth man is unknown, but he likely had the role of machine gunner. The driver’s position was rather exposed, as it was located behind a bulbous ‘nose’ at the front of the tank. The driver entered his positioned via a large door on the right of the ‘nose’. The rest of the crew entered via hatches on the flanks of the tank.

Background

The Irish were relative latecomers to the idea of tank warfare. Prior to the 1930s, the only experience they had had with armored vehicles was with a few types of armored cars, which included the Rolls-Royce and Lancias.
The Mk.D was tested in the U.K. by Ireland’s foremost advocate of armored warfare, Lieutenant Sean Collins-Powell. The lieutenant was the nephew of the assassinated Irish revolutionary, Michael Collins. He was trained at Aberdeen Proving Grounds, Maryland, USA in tank usage and application. Collins-Powell took delivery of the tank, then accompanied it back to Ireland.

The Mk.D at the Curragh. The Commander’s cupola is clearly visible atop the turret. Photo: Aaron Smith

Rendition of the Vickers Medium Mk.D by Tank Encyclopedia’s own David Bocquelet

Service

Unfortunately, not much is known about the Mk.D’s time in service with the Irish Army. We do know that it was assigned to the 2nd Cavalry Squadron of the Irish Cavalry Corps, based at the Cathal Brugha Barracks (Irish: Dún Chathail Bhrugha) in Rathmines, Dublin.

Irish troops surround the tank, listening to the instructor who stands at the driver’s position. The man is wearing the traditional ‘Glengarry’ hat of the Cavalry Corps. The turret is traversed all the way so what we can see here is its bustle and vacant Vickers MG position. Photo: aviarmor.net
The tanks would have been used for gunnery and combined-arms training with infantry at the Glen of Imaal (Irish: Gleann Uí Mháil) in the Wicklow Mountains. 5,948 acres of the Glen had been used as an artillery and gunnery range since 1900.
In 1934-35, the Mk.D was joined in the 2nd Armored by two Swedish L-60 Light Tanks. The small and nimble light tank built by Landsverk surpassed the slow and cumbersome Vickers, which was now largely outdated in almost every way.

The Mk.D at the Curragh followed by one of the L-60. Photo: Aaron Smith

Fate

The tank was officially removed from active service in 1937. In 1940, the Mk.D was damaged beyond repair while attempting to cross obstacles constructed by the Engineering Corps in a training operation. There is evidence to suggest that the tank’s engine may have also caught fire.
Following this incident, the tank was scrapped. The 6-Pounder armed turret was kept, however, and placed as a static turret as part of defenses outside of Curragh Camp, Kildare, where the tank spent its final years. Only the gun still survives, it is currently on display at the Curragh Camp Museum.

The Mk.Ds gun, the only surviving piece of the tank. Photo: Tank Archives

An article by Mark Nash

Vickers Medium Mk.D
Dimensions	5.33 x 2.5 x 2.4 meters (17.5 x 8.3 x 8 feet)
Total weight, battle ready	14 US Tons
Crew	5
Propulsion	Sunbeam Amazon 6-cyclinder gasoline engine, 170 hp
Speed	20 mph (32 km/h)
Armament	Low-Velocity 6-Pdr (57mm) Gun. 4 x 0.303 Vickers machine guns (7.7 mm)
Armor	Unknown
Total production	1

Links, Resources & Further Reading

www.curragh.info
www.geocities.ws/irisharmoredvehicles
www.wikitree.com
www.historyireland.com
Tiger Lily Publications, Irish Army Orders of Battle 1923-2004, Adrian J. English
Irish Army Vehicles: Transport and Armour since 1922 by Karl Martin
Mushroom Model Publications, AFVs in Irish Service Since 1922, Ralph A. Riccio

WW2 US Flamethrowers

E9-9 Mechanized Flamethrower

Post author By Mark Nash
Post date March 22, 2018
4 Comments on E9-9 Mechanized Flamethrower

United States of America (1943)
Flamethrower Tank – 1 Prototype

In 1943, the Standard Oil Company, based in Indiana, was one of the main companies charged with designing tank-based, or ‘Mechanized’ flamethrowers. Earlier in the year, in January, they had successfully tested their E7-7 model. This was a modified Light Tank M5A1 with the 37mm gun exchanged for a flame projector.

In April, Standard Oil was contracted to develop another tank based flamethrower. This time it would take the ‘Auxiliary’ form. Simply, this means that the flamethrower is secondary to the main gun, and does not replace it. This is unlike the ‘Main Armament’ flamethrowers, such as the M3A1 Satan or E7-7’s, which replaced the main gun.

This new flame thrower would be designated the E9-9 (this was the combination of the E9 Fuel system and E9 flame gun). The vehicle would follow the same designation, being called the E9-9 Mechanized Flame Thrower. It is sometimes known as the ‘Indiana-Merz E9’, though what ‘Merz’ relates to is unknown.

The E9-9 Mechanized Flame Thrower. Photo: Presidio Press

The M5A1

The M5 was the last in the lineage of light tanks which had followed the same design since the Combat Car M1 which entered service in 1935. Entering service in 1942, the M5 was designed to replace the now aging M3. It was originally going to be designated the M4, but to avoid confusion with the Medium Tank it was changed to M5.

Overall the design was similar. It shared the same vertical volute spring suspension (VVSS) and 37mm gun main armament. The real differences lay with the hull design and engine. The hull was a completely different design but followed elements used on the M3A3. Gone was the stepped armor layout at the front of the tank. It was replaced by a large sloped plate, granting more effective protection.

The original twin Cadillac Series 42 engine was replaced by another Cadillac model. This time twin V-8 automobile engines were used. The M5 gradually replaced the M3 in active service. After the fruitless M7 project, the M5 was replaced with the M24 Chaffee, a completely new design.

A Stuart Crocodile?

The aim of the E9 program was to produce a tank-based flame thrower with a large fuel capacity, a projection range of 200 yards (183 metres) and that would not reduce the M5A1’s original firepower. To achieve this, all the flame thrower equipment, such as the fuel tanks and propellent gas bottles, were placed in a trailer that was towed by the tank. The only part of the system installed on the tank itself was the flame projector, mounted on the front of the tank. This configuration is similar to the famous Churchill Crocodile and lesser-known Sherman Crocodile. Both of these flame throwing tanks kept all of their fuel and gas load in a towed, wheeled trailer.

By comparison with the trailers of its Crocodilian cousins, the E9’s was extremely large. It was approximately the same height and width as the tank itself. In this 12 ton trailer, there was a 1200 US gallon (5455 litre) armored steel tank. This would be filled with 800 US gallons (3637 litres) of flame fuel. The 400 US gallon (1818 litre) void that was left was employed as an air cushion. There were two air-compressors in the trailer which provided 800 psi from a bottle above the fuel tank.

The trailer was attached to the rear of the M5 via a 10-inch (254mm) diameter ball-and-socket joint. The joint granted the trailer the ability to turn 105-degrees left or right from the center line. The fuel line which fed the projector passed through this ball joint. In an emergency, the trailer could be jettisoned. Valves in the piping would close upon this action to prevent fuel from the tank spilling.

Another view of the E9 with 2 two crew members, showing the size of its large trailer. Photo: Osprey Publishing

The E9 Flame Gun

The flame projector was mounted in between the drive sprockets at the front of the tank. It was operated by the bow machine gunner/assistant driver through a series of pulleys and cables. The flame gun could traverse 60-degrees left and right, and elevate +30 to -15 degrees.

The E9 was a duplex flame gun, meaning it had two nozzles side by side. One nozzle was ¼ inch (6.35 mm) in diameter, the other was ¾ inches (19.05mm) in diameter. The thinner nozzle was tighter, this granted a higher pressure thus providing greater range. The wider nozzle did the opposite and provided a wider field of fire at closer ranges.

A diagram of the flame gun and puly system. Photo: Presidio Press.

Catastrophic Tests

The E9-9 project would come to a deadly end, meaning tests would never be completed. During a live fire trial on the 29th of May 1944, 500 US gallons (2273 liters) of Napalm thickened gasoline was provided and prepared in the trailer’s fuel tank. The tank was pressurized to 500 psi. During a fire test, one of the air compressors failed. Shortly after this, the main fuel tank exploded ripping the trailer apart and engulfing the M5 in flames. The incident was fatal, resulting in the death of all four tank crew. This catastrophe brought about an abrupt end to the E9-9 project, with all work halting. As a result, none of the E9 equipment survives today.

Illustration of the E9-9 without fuel trailer by Tank Encyclopedia’s own David Bocquelet

M3 Stuart specifications
Dimensions	4.62 x 2.39 x 2.33 m (15’2″ x 7’10” x 7’8″)
Total weight, battle ready	16.5 tons (tank) + 12 ton trailer (28.5 tons)
Crew	4
Propulsion	Twin Cadillac V8, 296 hp (220 kW), air cooled gasoline
Speed	58 km/h (36 mph) road 29 km/h (18 mph) off-road
Range	120 km at medium speed (74.5 mi)
Armament	E9 Flame thrower gun 37mm Tank Gun M6 1x Browning .30 Cal. (7.62 mm) M1919 machine gun
Armor	From 13 to 51 mm (0.52-2 in)

Sources

Presidio Press, Stuart – A History of the American Light Tank Vol. 1, R.P. Hunnicutt
Osprey Publishing, New Vanguard #186: US Marine Corps Tanks of World War II
Osprey Publishing, New Vanguard #206: US Flamethrower Tanks of World War II
Fort Leonard Wood, U.S. Army Flame Thrower Vehicles, Part 1, Captain John Ringquist

Cold War US Light Tank Prototypes

76mm Gun Tank T92

United States of America (1952-1958)
Light Tank – 2 Prototypes Built

In May of 1952, the hunt was already underway for a new light tank that would replace the M41 Walker Bulldog which had only entered service the previous year. Three companies were competing for a production contract. These were the Cadillac Motor Car Division (CMCD) of General Motors Corporation (GM), Detroit Arsenal (DA), and Aircraft Armaments Incorporated (AAI).
Cadillac and Detroit would compete individually with their own designs. These would both be designated as the T71. The T71 was rather traditional in its design when comparing it to AAI’s proposed tank, which was rather unique, to say the least. As such, the latter vehicle would receive the designation of T92.

The initial T92 prototype. Photo: Presidio Press

Development

After review, a contract was handed to the AAI to produce a full-scale mock-up. Their tank was considered an extremely innovative design which offered greatly improved performance over previous light tank models. This also meant that it included newly developed features including some which were so novel they had never been tested before, which is considered risky when building a new tank.
The Chief of the Army Field Forces and the Assistant Chief of Staff authorized development of the tank in late July 1953. The United States Ordnance Technical Committee also approved the design in March 1954, with clearance given to produce a pilot vehicle. On the 18th June 1954, AAI was given permission to build an additional pilot vehicle. Meetings on the 5th of November 1954 and 27th of January 1955 resulted in recommendations for numerous design changes.
Development continued into January 1956, at which point the competing T71 project was canceled. This was thanks, in no small part, to the rapid progression of the T92, and the troublesome development of the T71 which ran into funding issues.

Design

Hull

Welded steel armor and castings formed the hull of the T92, which was extremely flat and made up of oblique surfaces. The hull was wedge-like in its shape and extremely low profile. One of the more outlandish thoughts behind the shape was that it would help to deflect the blastwave of a Nuclear Blast should it have taken one head on.

A comparative image showing the size difference between the T92 and the M41 Walker Bulldog. Photo: Presidio Press
The armor thickness was almost identical to the M41, which was 31.7mm (1.2 inches) at its thickest, but it was considerably lighter at 18-tons than the 26-ton Walker Bulldog. This was due to a reduction of overall parts, with some constructed from Aluminum alloy. Such parts included the access doors of the power plant, generator, and battery compartments. The fenders were constructed from a blend of Aluminium and fiberglass reinforced plastics. It was designed to be as light as possible to allow it to be air-transported or deployed via-parachuted drop.
Access into the hull, as well as the various cupolas over the various crew positions, was through a rather large, square two-part armored door in the rear. Each door was fitted with a vision block. To the left of the doors was stowage for the pioneer tools (shovel, pick-ax, etc). To the right was stowage for two fuel “Jerry” cans. These were stored vertically with one on top of the other.

A view of the rear of the tank showing the two-part door and stowage positions. This is the updated vehicle with the added idler wheels. Photo: Presidio Press

Mobility

The T92’s power pack consisted of a 357 horsepower AOI-628-1 (AOI: Air-cooled, Opposed, Inline) engine that was located in the front right of the hull. It was connected to an Allison XT-300 transmission providing 6 forward and one reverse gear. The top speed on road was 35 mph (56 km/h). There were two air intakes; the large grill on the upper glacis and a ‘mushroom’ ventilator at the right front of the turret. The exhaust ran to the back of the vehicle under the right sponson, ejecting fumes through a grille at its rear. The whole power pack (engine & transmission) could be removed and installed as one piece. Fuel was stored in two 75-gallon (341 liters) bladder-type tanks for a total of 150 gallons (682 liters). These bladders were located at the rear of the hull.
The driver sat to the left of the engine, just in front of the turret ring and was protected by a steel firewall. The vehicle was operated by two small control handles that were used to steer and brake. He had a hatch above his head fitted with vision blocks. It swung open to the left on a pivot. There was also an escape hatch beneath his position.
Suspension on the T92 consisted of a Torsilastic system which is not commonly used on armored vehicles. In the case of the T92, this consisted of a cylinder attached to the hull sides. This intern, consisted of a hollow shaft and a coaxial tube, with rubber between the shaft and the tube. The rubber was sulfurized to make sure the shaft and the tube were firmly attached. The Torsilastic suspension type eliminated the friction between metal parts and thus did not need to be lubricated as often as standard suspension types. The rubber acted as an elastic element, as well as a shock absorber, meaning the vehicle could be quieter and more comfortable to drive. This suspension system was also used on some LVT models and the M50 Ontos. The external nature of the Torsilastic suspension saved a great deal of room inside the vehicle that would otherwise have to accommodate the long torsion bars of a traditional suspension. There were 4 road-wheels per-side, each with a corresponding suspension unit. The drive wheel was at the front, and did not have traditional external teeth. There were long posts around the wheel which slotted in guide holes in the track which would pull it around. In the initial design, there were no return rollers. As such, the track would’ve been quite slack over the return which could result in ‘track-slap’ damage or the loss of the track. The meetings of November 1954 and January 1955 brought this to light, and it was recommended that at least two return rollers be installed. One was installed behind the suspension unit of the second road wheel, the other was installed behind the suspension unit of the last road wheel/trailing idler.
The tracks were a band type which did not require pins to hold the links together. They were mostly rubber and reinforced with steel cable, and were rather thin at just 16-inches (40.64 cm) wide. The full length of the track was 390.25 inches (9.91 meters), composed of nine separate sections. Two spare sections were stowed on the gun cradle at the rear of the turret.

Photo: Presidio Press

Turret

The turret and arrangement of the T92’s armament was perhaps the most unique feature of the vehicle. It sat on an 89-inch ring and was cleft in its design, with a large hollow in the middle cut out for the 76mm Main Armament. On either side of the gun were two cupolas which could rotate independently of the turret and were armed with machine guns. The one to the right of the gun was the commander’s and the one on the left was for the gunner. These cupolas were based on commander’s cupolas found on the M48 and M60 tanks. In the initial design of these, it was intended for both of them to be armed with Browning M2 .50 Caliber (12.7mm) machine guns. However, in the meetings of November 1954 and January 1955, it was decided to replace the machine gun in the Gunner’s cupola with a Browning M1919 .30 Caliber (7.62mm). The cupolas retained the ability to mount either weapon.
As well as the vision blocks in these cupolas, both the gunner and the commander were equipped with periscopes that enabled them to look over the gun. The cupolas were manually traversable but could also be brought into line with the main armament with the use of hydraulic slewing motors. The traverse range was 194 degrees, 10 degrees inboard forward, and 4 degrees inboard aft. The machine guns could elevate manually through a range of +60 to -10 degrees. Beneath each cupola was a suspended seat for the respective crew member to sit on, under which were drums for the machine gun ammo.
Both the gunner and commander could traverse the turret, aim and fire the main armament. The power elevation and traverse controls, as well as the gunnery controls, were mirrored in the commander’s position. The commander could override the controls to lay the gunner on to a target or engage it himself.

The early version of the T92 utilized a trailing idler wheel instead of the traditional raised version which was added to the vehicle at a later date. This side view shows off the Tank’s unique profile. Illustration by Tank Encyclopedia’s own David Bocquelet.

Armament

Main armament of the T92 consisted of the 76mm Gun T185E1. This gun was ballistically the same as the 76mm Gun M32 found on the M41 Walker Bulldog and was even fitted with the same T-shaped single-baffle muzzle-break and fume extractor. This gun could fire Armor-Piercing (AP), High-Velocity Armor-Piercing (HVAP) and High-Explosive (HE) rounds.

A top down view of T92 pilot number 2 after arrival at Aberdeen on 22 July 1957. Note the unique turret and armament arangment. Photo: Presidio Press
The major differences with the weapon was its quick-change barrel, and the fact it was mounted upside down. This was to accommodate a semi-automatic loading system. The loader, who was seated in the left rear of the vehicle, placed one of the tank’s sixty 76mm rounds (28 in the main rack, 24 in the dispenser rack, 7 in the ready rack, and 1 kept in in the loading system) onto a tray behind the breach. When it is properly seated on the tray, it is automatically locked into position. The loader then held down a button for the duration of the cycle which consisted of the round being brought into line with the breach (whatever the guns state of elevation) and rammed in. The gun also featured a fully-automatic ejection system. When fired, the gun’s recoil would push the spent cartridge out of the tank through a small void in the armored box surrounding the breach. This was seen as essential as without it, the small crew compartment of a light tank like the T92 would soon fill with large, empty 76mm cases and the resulting irritant fumes.
The gun was mounted in a cradle in the center of the turret. The breach end was protected in an armored box and extended back to the rear of the turret. When the gun was depressed, the breach end lifted out of the turret roof. When the gun was elevated the breach sank into the hull. The voids created between the gun and body of the turret were covered with a canvas screen. Maximum elevation was +20 Degrees, maximum depression was -10 degrees. A semi-circular cage which acted as a guardrail was installed at the rear of the turret to protect the breach. It was to this that spare track sections were stored. Mounted above and to the left of the main gun was a coaxial Browning .30 Cal (7.62mm) M1919/M37 machine gun.

Tests

T92 Pilot No. 1 arrived at the Aberdeen Proving Grounds (APG) for tests on the 2nd of November 1956. Due to a miscommunication with constructors, some parts were missing from the vehicle. Namely, the Commander and Gunner’s cupolas. Weights were added to the positions to simulate for the automotive tests before the cupolas arrived at Aberdeen and fitted. T92 Pilot No. 2 arrived at Aberdeen on the 22nd of July 1957. This vehicle was used to evaluate the crew and their respective compartments and positions. At the time, it was expected that the T92 would enter full-scale production by mid-1962.

The T92 (with original tracks) taking part in cross-country tests. Photo: Presidio Press
Testing at Aberdeen identified a number of areas where the tank needed to be improved. These were mostly with the suspension. The band type track proved to be prone to breakage and throwing. After just 202 hours of test time, the track was replaced with the thinner (14-inch/35.56 cm as opposed to 16-inch /40.64 cm) traditionally linked tracks of the Light Tank M24 Chaffee. There were no long-term plans to keep this track for the production model, and plans were made to design a stronger band-type track. The adoption of this track necessitated the modification of the sprocket wheel to the traditional type with external sprocket teeth.
Another attempt to stop the track being thrown was the addition of a compensating idler wheel. This was the most drastic of the changes. Such idler wheels were mounted on a lot of tanks of the era, such as the M48, M60 or M103. They are attached to the closest roadwheel by an actuating arm. When the roadwheel reacts to terrain the idler is pushed out or pulled in, keeping constant track tension. These were mounted on a frame that was welded to the vertical rear plate of the tank.

The revised T92 with the added compensating-idler and the tracks of the M24 Chaffee. Photo: Presidio Press

Fate

In 1957, funding was made available for two further Pilot vehicles, each one would have the suggested improvements incorporated. Delivery of these was expected by mid-1958. However, the order was canceled prior to completion.
In 1957, it was discovered that the Soviets were working on an amphibious capable light tank. This would later come to be identified as the PT-76. The T92 was assessed to see if it could be made into an amphibious vehicle. This was soon proved to be unfeasible. The effectiveness of the 76mm gun was also now called into question. In a time where the larger 90mm gun was beginning to struggle, the 76mm was now seen as obsolete. Following this, the T92 project was canceled in late 1958. Light Tank design work would then focus on the United State’s own amphibious light tank, ultimately culminating in the problematic M551 Sheridan.
One surviving T92 was preserved for a long time at the United States Army Ordnance Museum at the Aberdeen Proving Grounds in Maryland. The tank has since been removed from the site with the closure of the museum in late 2010. It was moved to Fort Lee in Virginia where it currently resides in storage.

An article by Mark Nash

Specifications
Total weight, battle ready	18 tons
Crew	4 (Commander, Driver, Loader, Gunner)
Propulsion	357 horsepower AOI-628-1
Top speed	35 mph (56 km/h)
Suspensions	Torsilastic
Armament	76 mm (3 in) gun T185E1 .50 Cal (12.7mm) Browning M2 2X .30 Cal (7.62 mm) Browning M1919A4/M34
Armor	Up to 31.7mm (1.2 inches) thick
Production	2 Prototypes

Links, Resources & Further Reading

Presidio Press, Sheridan: A History of the American Light Tank, Volume 2, R. P. Hunicutt
Osprey Publishing, New Vanguard #153: M551 Sheridan, US Airmobile Tanks 1941–2001
Profile Publications Ltd. AFV/Weapons #46: Light Tanks M22 Locust and M24 Chaffee, Colonel Robert J. Icks
US Archives

United States of America (1945) Mechanized Flame Thrower – 3 Prototypes

Turret

Weaponry

Production

Fate

Specifications

Links, Resources & Further Reading

Republic of Ireland (1940) Tankette – 226 Purchased

The Universal Carrier

Irish Service

Fate

Specifications

Links, Resources & Further Reading

Republic of Ireland (1980) Light Tank – 14 Purchased

The FV101 Scorpion

Irish Service

Fate

FV-101 specifications

Links, Resources and Further Reading

German Reich (1944) Flamethrower Tank – 20 Built

The Jagdpanzer 38(t)

Design of the Flammpanzer

Action

Descendant

Flammpanzer 38(t) specifications

Links, Resources & Further Reading

Design

History

Advantages

Disadvantages

Outcome

Tanks & AFVs with Oscillating Turrets

France

United States of America

Austria

Sweden

Germany

Great Britain

Italy

Links, Resources & Further Reading

German Reich (1942-1943) Heavy Tank – 1 Converted

Background, the KV-1

KVs in German Service

German Modification

Gun

Turret Changes

But, Why?

Specifications

Links, Resources & Further Reading

United States of America (1952) Heavy Tank – 2 Turrets Built

Development

Hull

Turret

Links, Resources & Further Reading

Armament

Autoloader

Crew

Fate

Specifications

United Kingdom/Irish Free State (1929) Medium Tank – 1 Built

Ireland’s First Tank

Design

Background

Service

Fate

Vickers Medium Mk.D

Links, Resources & Further Reading

United States of America (1943) Flamethrower Tank – 1 Prototype

The M5A1

A Stuart Crocodile?

The E9 Flame Gun

Catastrophic Tests

M3 Stuart specifications

Sources

United States of America (1952-1958) Light Tank – 2 Prototypes Built

Development

Design

Hull

Mobility

Turret

United States of America (1945)
Mechanized Flame Thrower – 3 Prototypes

Republic of Ireland (1940)
Tankette – 226 Purchased

Republic of Ireland (1980)
Light Tank – 14 Purchased

German Reich (1944)
Flamethrower Tank – 20 Built

German Reich (1942-1943)
Heavy Tank – 1 Converted

United States of America (1952)
Heavy Tank – 2 Turrets Built

United Kingdom/Irish Free State (1929)
Medium Tank – 1 Built

United States of America (1943)
Flamethrower Tank – 1 Prototype

United States of America (1952-1958)
Light Tank – 2 Prototypes Built