FV4005 Stage I & II

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

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

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

FV 214 Conqueror

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

Design and Development

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

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

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

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

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

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

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

Stage I

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


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

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

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

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

 

Stage II

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


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

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

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

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

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

Fate

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

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

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

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

FV4005 Stage II Specifications

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

Links, Resources & Further Reading

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

ELVO Leonidas

Greece (1982)
APC – 900+ built

About ELVO company

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

Leonidas 2 APC

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

Design of the Leonidas I

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

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

Leonidas 2 APCs

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

Development of the Leonidas II

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

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

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

Leonidas 2 IFV – rear view

Fate

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

Video: Short documentary about ELVO

Links

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

Leonidas 2 Specifications

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

Conqueror FV214

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

From the “Universal Tank”

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

Design

Protection

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

Conqueror Armour scheme

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

Mobility

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

Conqueror Mk. I at Bovington

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

Armament

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

Conqueror Mk. I rotatable Tank Commander Cupola at Bovington

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

Conqueror Mk.I on trials in 1956

Evolution

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

FV221 Caernarvon

The FV221 Caernarvon

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

Conqueror ARV2 FV 222\

FV222 Conqueror ARV

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

In Action

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

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

Sources/Links about the Chieftain

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

Video: Duxford Tankfest 17/06/2012

Conqueror Specifications

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

Flakpanzer 1 Gepard

Western Germany (1965)
SPAAG, 377 built

In 1966, the Bundeswehr (German Army) was looking to replace its now redundant American-supplied M42 Duster Self-Propelled Anti-Aircraft Guns (SPAAGs). Two projects were investigated. These were the ‘Matador’ (designed by Rheinmetall, AEG, Siemens, and Krauss-Maffei) and the ‘5PFZ-A’ (designed by Oerlikon, Contraves, Siemens-Albis, Hollandse Signaalapparaten and Kraus-Maffei/Porsche). In 1971, it was finally decided that the 5PFZ was the better vehicle, and as such a test batch of four 5PFZs, with the designation of ‘B1’, were delivered. Another pre-series batch of twelve 5PFZ-B1s were delivered in 1973.

By September 1973, the vehicles had received the name Flugabwehrkanonenpanzer Gepard (often shortened to Flakpanzer Gepard. Gepard meaning Cheetah in English). The first order for the vehicle totaled 420 units. After the first 195, the remaining 225 were equipped with a Siemens Laser Rangefinder. These Gepards were given the B2 identifier.

The Gepard has served non-stop since its introduction and has only started to see retirement in 2010. It has served with a number of countries.

Bundeswehr Gepard 1A2. Photo: Hans-Hermann Bühling

A Fearsome Feline

Like its World War II namesake, the Flakpanzer 38(t), the Gepard was based on the hull of an existing tank. The tank chosen was Germany’s own Leopard 1 Main Battle Tank (MBT). Entering service in 1965, the Leopard 1 is one of the most famous tanks of the Cold War and Modern Era. It was lightly armored, but extremely mobile and armed with the potent British L7 105mm Rifled Gun.

After countless upgrades and derivatives, the tank was replaced in the Bundeswehr by 2003, by its successor, the Leopard 2. However, it continues to serve around the world in countries such as Turkey, Brazil and Greece.

The Gepard’s hull remained almost identical to the Leopard original, aside from a slight increase to the distance between the third and fourth road wheels. This also resulted in a slightly longer hull. The engine deck was also extended to house an additional six 24 volt batteries. Under the engine deck is the same the 830 horsepower MTU MB Ca M500 diesel engine used in the Leopard. This propelled the vehicle to 40 mph (65 km/h). The SPAAG was also equipped with a secondary Daimler-Benz OM 314 4-cylinder diesel to supply energy to the tank’s electrical systems. This engine is located in the front left of the hull where the original Leopard had an ammunition rack and works through 5 generators that power the turret’s traverse, gun elevation, and radar systems. The exhaust for this motor runs along the left-hand side of the hull.

The Gepard’s turret is lowered on to an awaiting hull. Photo: Peter Favier on Pinterest

The Gepard is operated by just 3 crew members consisting of a Driver, a Gunner and the Commander. The Gunner sits on the right-side of the turret with the Commander on the left. The driver remains the hull. The Gunner and Commander stations are equipped with stabilized panoramic sights which are incorporated into the turret roof. The sights can be paired, or ‘slaved’ to the tracking radar. The Commander is equipped with hand held viewing equipment when operating open-hatch. Both of these men share a large one-piece hatch in the turret roof.

Turret and Weaponry

The turret is the major change from the Leopard and houses the equipment that, at the time of its creation, made the Gepard one of the most deadly Anti-Aircraft vehicles ever built. The Gepard’s primary weapons are dual 35 mm Oerlikon KDA autocannons which are 90 calibers (3.15 m, 10 ft 4 in) long. As well as the full 360 degrees rotation of the turret, the guns can be elevated to almost a 90-degree vertical angle. The muzzle of the guns are fitted with a projectile velocity sensor. Each gun has a 550 rounds per minute rate-of-fire, with a combined rate of 1,100 rounds per minute. The cannons are chambered for 35×228mm standard NATO issue rounds. These include SAPHEI (Semi Armor-Piercing High-Explosive Incendiary), HEI (High-Explosive Incendiary) and FAPDS (Frangible Armor-Piercing Discarding-Sabot).

The Gepard firing its guns in a training exercise. Photo: SOURCE

The vehicle carries a mix of these ammunition types, holding 620 rounds in total. This amount is split equally between the guns. 40 Anti-Tank rounds are carried near the breaches of each gun for quick loading should the vehicle have to defend itself from attacking enemy tanks or IFVs (Infantry-Fighting Vehicles) in an emergency. The rounds are fed in by disintegrating belts. When fired, the links and spent cases are ejected from the elevation hub of the guns.

The cannon’s work in conjunction with the radar systems and a laser rangefinder. The Gepard started out with Doppler Radars. These work by using the Doppler effect to calculate velocity and distance data of a selected target. The same technology can be found in the speed guns used by Police. An MPDR-12 Doppler surveillance or ‘Search’ radar is mounted on the rear of the turret. This revolves 60 times per-minute and has a range of 15 kilometers (roughly 9 ½ miles). It is mounted on a swinging arm. When in use it is raised, when it’s off it is lowered. This radar searches for targets in the assigned airspace. When an aircraft is pinged and identified as hostile, the Doppler ‘Tracking” radar mounted on the nose of the turret takes over. This radar can rotate 180 degrees left and right and also a range of 15 kilometers. Once it is locked on, it automatically tracks the target in azimuth, elevation, and range.

Romanian Gepard in service – src wikimedia commons, lt.col Dragoş Anghelache. Photo: SOURCE

Upgrades

Over its career, the Gepard received a number of upgrades to its electrical systems. Some upgraded vehicles have a digital FCS, these were designated B2Ls. The Doppler radars were replaced as well. The Search radar was replaced with an S Band Radar (S band: Part of the microwave band of the electromagnetic spectrum covering frequencies from 2 to 4 gigahertz (GHz), used by NASA and in Bluetooth and WiFi devices). The Tracking with a Ku Band radar (Ku band: Part of the microwave band of the electromagnetic spectrum covering frequencies from 12 to 18 gigahertz (GHz), originates from the original K band used by NATO). These upgraded radars retained their 15-kilometer range.

In operation, the Gepard would often be deployed with Stinger Surface-to-Air (SAM) teams to take advantage of the scanning range of the Gepards equipment. In later models, the Gepard was equipped with attachment points on the gun elevation hubs for dual tubed ManPad (Man Portable Air Defence) SAM launchers. This was not very common and was surpassed by SAM armed Ozelot Light Flak vehicle, based on the Weasel Light AFV.

The “Flakpanzer Leclerc”. Notice the two Stinger missiles connected to the gun arm. Photo: TankPorn of Reddit

A version of the Gepard 1A2 was also proposed with two Stinger missiles attached to each of the guns. However, it was not accepted by the Bundeswehr. The Flakpanzer Gepard turret was also proposed for mounting on the French Leclerc MBT. The demonstrator also has the missiles mounted. However, nothing more came of it.

Phasing Out

As already stated, the Flakpanzer Gepard started to be phased out in the late 2000s. It is in the process of being replaced by the MANTIS (Modular, Automatic and Network-capable Targeting and Interception System) gun system.

Export

Netherlands

PRTL ‘Pruttel’
The Netherlands was the second largest user of the Flakpanzer 1, receiving 95 of the vehicles. In Dutch service, it was renamed Pantser Rups Tegen Luchtdoelen or PRTL. Translated to English, this literally means ‘Armour Track Against Air Targets’. It was often pronounced as ‘Pruttel’ (meaning ‘Sputter’) by its crews, perhaps as a result of the sound of the cannons when fired.

The Dutch Army did modify the scanning equipment of the Flakpanzer. They switched the Search Radar to X band, part of the microwave band of the electromagnetic spectrum covering frequencies from 7 to 11.7 gigahertz (GHz). The Tracking radar was replaced with Ka Band, Part of the microwave band of the electromagnetic spectrum covering frequencies from 26.5 to 40 gigahertz (GHz). Like Ku, Ka band is a further development of the NATO K band.

The PRTL has begun to see retirement in the Dutch Army with only 57 currently remaining operational. Some of the surplus has been sold to other countries.

The Dutch PRTL ‘Pruttel’, note the different radar equipment. Photo: Peter Favier of Pinterest

Other Countries

Brazil: 36 vehicles, still in operation.
Jordan: 60 vehicles previously Dutch PRTLs.
Chile: Only 4 ever received after the original order for 30 vehicles was abandoned due to financial issues.
Belgium: Operated 55 vehicles, now withdrawn from service.
Romania: 43 vehicles still in operation.

Eastern Cousin, the Type 87

The Japanese took great interest in the Flakpanzer Gepard, so much so that they built their own version based on the hull of the Type 74 Main Battle Tank. The vehicle was designated the Type 87. The weaponry was supplied by Oerlikon. To avoid patent infringement claims, the arrangement of the sensory equipment was altered. The Search radar remained at the back of the turret, but the Tracking radar was moved to the turret roof. The SPAAG is currently in service with the Japanese Ground Self-Defense Force (JGSDF), who operate 52 vehicles.

The Japanese Type 87, note the similarities to the Gepard. Photo:

Gepard Specifications

Dimensions (L-W-H) 9.54m (7.09m without gun) x 3.25m x 2.61m
(31’3″ (23’3″) x 10’7″ x 8’6″ ft.in)
Total weight, battle ready 42.2 tons (84,400 lbs)
Crew 4 (driver, commander, gunner, loader/radio)
Propulsion MTU MB 838 10-cyl 37.4 L, 830 PS (610 kW)
Suspension Independent torsion bars
Speed (road) 65 km/h (40.4 mph)
Range (road/cross-country) 600/450 km (373/280 mi)
Armament
Armor 19-21 mm steel plus 10-70 mm RHA (0.75-0.83 + 0.39-2.76 in)
Total production (all MBT versions) 4,744 in 1965-85

Links, Resources & Further Reading

Osprey Publishing, New Vanguard #16: Leopard 1 Main Battle Tank 1965–95
On WeaponSystems.net
On Military-Today.com

Cadillac Gage Commando M706

 U.S.A. (1963)
Armoured Car – about 9000 built all combined V-100, 150 & 200.

Development of the M706

Terra-Space division of the Cadillac Gage company designed in 1960 4×4 amphibious armoured vehicle, expecting to fulfill the future needs of the army. The later required some sort of Jack-of-all-trades, a multi-purpose, 11-man APC, reconnaissance vehicle, convoy escort, command, patrol and a riot vehicle. By 1962, the patent was filed, and the projected vehicle named Commando. Development was fast as in 1963, the prototype undergone its first tests. The same year, the definitive production vehicle, the V-100, was tested thoroughly in Vietnam before the production was started in 1964. Total production figures are ellusive but at least 10 000 vehicles of the V-100, 150 and V-200 variants were delivered by CGC, then the Textron Marine & Land Systems company. The M706 is currently replaced by the M1117 since 1999, but still in service in many countries. Philippines are one of the most prolific user of the model.

Design

US Air Force Security Policemen aboard a V-100 (XM-706E2) during exercise Team Spirit ’81.

To kept the prices low, the vehicle used many existing components. The axles were similar to the M34 truck series while the engine was the same V8 Chrysler, 360-cubic-inch gasoline that powered the M113 armoured carriers. It had a 5-speed manual transmission. These allows a top speed of 62 mph (100 kph) over rough terrain. Its 4×4 independent sprung roadwheels had massive tires to reduce ground pressure. The CGC can also swim at 3 mph (4.8 kph). Protection was provided by the “Cadalaloy”, a custom 0.25 in hardness alloy steel, protecting against small arms fire (7.62 cal.). This protection was also given by the well-sloped monocoque welded hull, also protecting the crew from mine blasts. However the alloy was not espcially light, and the empty weight of the vehicle was 7 tons.

This take its toll on the rear axle, which frequently failed, and not designed to support this extra load. Access was allowed from the two side doors, and the turret cupola hatch. Vision was provided by height vision blocks (at first ten) with armoured glass, and the revolving turret which featured a peripherical vision with ten vision blocks, plus a periscope. For close-fire, six pistol ports were also provided on the upper sides. The hull featured also an internal modular arrangement with interchangeable components, aimed at the export market.

The CGC accepted a large array of weapons. The first military version V-100 was usually armed with the same revolving turret that equipped the M113, armed with a twin M37 browning cal.30 (7.62 mm). This was in standard, but some versions received an upper open supertructure and one to three Browning cal.50 (12.7 mm), the front one being protected by an armoured shield. Later on, the revolving turret was equipped with smoke dischargers and a M2 cal.50. Additional supports were sometimes welded for extra M60s. An export version accepted a M134 7.62mm Minigun. The V150 and V200 were more heavily armed and better used for recce and support. According to the Wall Street Journal in 1965, the base price tag for the M706 Commando was 24.500 $.

The V100

This was the main, early production version. Apart the facts given above, there were two basic versions, a turret one, and an open-top version, with added upper protections. The side door, at first, in single piece, was later produced in two-parts. In 1964, one of the XM 706 prototypes tested a 20 mm armed turret, which never made it before the reinforced and longer V-150. The vehicle impressed the ARVN (Allied south Vietnamese Army which became the first customer of the V-100, apart the ATAC (US Army Tank & Automotive Command).

A former V-100 from Viet-Nam, at Engineering School, Fort Leonard Wood, Missouri – Wikipedia, creative commons.

A 40 mm automatic grenade launcher and new turrets were also quickly developed since the AVRN complained about the lack of firepower of the twin cal.30. But the project failed to meet the US Army requirement and failed to materialized after US troops disengaged from VN in 1972-73. The USAF received the XM706E2, wiyh an open-top center parapet with with a single M2HB machine gun under mask assisted by a M60 or two. Some were still in service at Clark AFB in the Republic of the Philippines in 1988. In patrols, a crew of 12 was often seen, but it was systematic in ARVN forces.

The V200

The development was assumed by the Marine and Land Division of the Textron company. It was an elongated V-100 (in the middle section), partly based on U.S. Army’s 5 ton trucks components. It was built solely for export for the needs of the Singaporean army, or Singapore Armed Forces (SAF). Tey were modernized by ST Kinetics in the early 2000s and are still in service. Today singapore has 250 of these in service, plus 30 V-100 and 50 V-150.

Singapore Army V-200 Commando with 20mm cannon

The V150

This vehicle was based partly on the V-100, and the V-200. This hybrid was shorter but stronger and could accomodate much heavier turrets and armaments, and could be equipped with diesel or gasoline engines. Built for export, it was equipped with a large variety of armament configurations, including 12.7 mm and 20 mm armed turrets. Portugal had its V-150s modernized in the 1970s as the Chaimite, with a 90 mm Cockerill gun turret, known as the V-400 variant.

Saudi Arabian V-150, 1st gulf war, 1991.

2,968 LAV-150 vehicles were produced. The list of operators includes Bolivia (10), Bostwana (36), Cameroon (43), CHAD (9), Dom. Republic (8), Gabon (9), Guatemala (7), Haiti (6), Indonesia (200), Jamaica (13), Kuwait (20), Malaysia (184), Mexico (28), Philippines (165), Qatar (8), Saudi Arabia (1100), Singapore (280), Somalia (10), Sudan (100), Taiwan (300), Thailand (162), Turkey (125), USA (10), Venezuela (130), Vietnam (5).

Other Variants

The LAV-300 is a 6×6 version, partly based on the V-150.
The LAV-600 is developed from the LAV-300 with much heavier weapons, the most common being the 105 mm.
By 2013 Textron unveiled the Commando Select 90 mm Direct Fire, a new model aimed at export-market, armed with a CMI Defence Cockerill CSE 90LP weapons system and asked to perform a large range of misssions from conventional combat to counter-insurgency operations.

Active Service

The characteristic sloped hull of the CGC quckly earned the nicname “duck” or “the V” in Vietnam, which was its first active assignation. CGCs were massively deployed there, as available, for patrolling the DMZs and acting as military police vehicle, guarding AFBs (Air Force vehicles), and for other tasks. These were hard-pressed, especially at the time of the Têt offensive in 1969 when Viet-Minh commandos attacked several key points in Saigon and many other important cities. ARVN forces also actively used their vehicles after US troops disengaged from Vietnam in 1972-73.

US Air Force XM706 V-100, Tuy Hoa, 1968, Vietnam. Credits wikimedia commons

Many were captured by the NVA. After Vietnam, these vehicles saw limited use, and were affected to specific areas, like the Herlong Army Depot in California, and spent as targets. Other armies held their vehicles in service for longer periods, especially the Philippines. Many are still in operations. Outside these regular armies (Royal Thai Army, Republic of China Military Police, the Philippine Army, Marine Corps & Special Police Action Force, the Lebanese Armed Forces, the Army of Venezuela and the Jamaican Defence Force.), these vehicles has been used by many other operators for crowd control and anti-riot operations. SWAT teams also used some, as well as the LAPD. Later in 1991 gulf war, Saudi Arabia\’s guards V-150S took part in the battle of Khafji against Iraki forces.

Several 90mm and 20mm V-150s of Haitian Army seized by the U.S. military during Operation Uphold Democracy, 24 September 1994.

M46 links & resources

The CGC M706 on Wikipedia
On Global security
About the V-150

CGC M706 V100 Specifications

Dimensions (L-w-H) 18ft 7in x 7ft 5in x 8ft 4in in (5.69 x 2.26 x 2.54 m)
Total weight, battle ready 9.8 tons (21 800 lbs)
Crew 3+2 (Commander/radio, Driver, Assistant driver, Gunner, loader)
Propulsion V-504 V8 turbocharged diesel engine, 202 bhp, ptw ratio 18.75 bhp/ton
Maximum speed 60 mph (100 km/h) road, 3 mph water
Suspensions Independant, 4×4
Maximal range 400 miles (643 km)
Armament Main: twin M37 Browning cal.30 (0.3 in) MGs. See notes
Armor 0.25 in (6.35 mm)
Production (V100) estimated 5000

 

Cargo Carrier M29 Weasel

U.S.A. (1942)
Cargo Carrier – 15,892 Built

In 1942, the American Studebaker company based in South Bend, Indiana, famed for their luxury automobiles, answered a call for an armored vehicle capable of traversing deep Norwegian snow drifts for special forces operations. The vehicle became the M29 Weasel and went on to be a popular universal vehicle outside of its original intended use, akin to the British Universal Carrier. The M29 could traverse the hardest of terrains where wheeled vehicles could not go and saw service through the Second World War, the Korean War, the Vietnam War and saw use in the civilian sector.

An M29 named ‘Snookie’, date and location unknown. Photo: www.studebaker-weasel.com

Background

The idea for the Weasel came from the British Inventor Geoffrey Pyke, a man famed for his unorthodox methods. His most famous invention was Pykrete, a material that would’ve been used for the Habbakuk iceberg aircraft carrier. Pyke had long planned for Commando assaults on German power plants and industrial areas in Norway and also planned actions to interrupt the Nazi atomic weapons program in Operation Plough. Operation Plough is very much the origin of the Weasel. Pike called for a small, lightweight and fast vehicle, able to transport small teams of men across deep snow to take them deep into enemy territory.


The T15 Prototype in testing. Photo: www.studebaker-weasel.com

Design

The proposed design was designated T15, with the finalized design receiving T24. It was soon accepted and became the M29, a simple vehicle consisting of little more than a box on tracks. The Studebaker company would go on to build almost 16,000 M29s. Key elements of its design required that it be air-transportable, able to withstand the impact of a parachute drop, and able to carry enough supplies for a small commando team. It was powered by a 70 hp Studebaker Model 6-170 Champion 6-cylinder engine which propelled the vehicle to 36 mph (58 km/h), a speed it could sustain over most terrain types.

Suspension for the M29 consisted of rear mounted drive wheels (and transmission) with idlers in the front that were lower, giving the running gear the appearance of leaning forward. It featured four, two-wheeled bogies on each side, with two track return rollers. It had wide tracks from 15″ (380 mm) to 20″ (510 mm). This gave the Weasel a very low ground pressure of just 1.9 psi (Pounds Per Square Inch)a benefit in crossing soft ground. The tracks consisted of long metal plates connected by inner rubber bands, with a total of four bands per track, two on the outer edge and two in the center with a center guide horn. The bogie wheels ran on the center bands and. the outer face of the tracks featured two rubber blocks per link for grip on road surfaces.

A Weasel freeing a Willys Jeep from thick mud.

The M29 was operated by one driver and could carry three passengers. The driver was positioned in the front left with the engine compartment to his right and a row of three seats in the rear for the passengers. Though officially an unarmed vehicle, Browning M1919 .30 cal or .50 cal M2HB Machine Guns were often mounted for some form of offensive/defensive capability.

Variants

M29C Water Weasel

The M29C was the main variant of the Weasel. The M29 was already partly amphibious, able to traverse shallow and calm waters such as rivers and streams, but could not operate in rough, sea like waters. The M29C amended this issue, with the addition of buoyancy aids in the rear of the hull as well as two rudders. Removable pontoons were also added to the front and rear and.changes were made to the treads of the track links to allow it to propel itself in water, although it was very slow. This still didn’t make the M29 capable of seaborne amphibious landings, but allowed to be more stable in deeper or slightly rougher inland waters.

The M29C Water Weasel during testing.

M29/M29C Type A, B and C

These variants were all virtually unchanged from the standard M29/M29C, the only difference being that these were armed versions. The Type A featured a center-mounted 75mm M20 recoilless rifle. The Type B featured a rear-mounted 75mm Recoilless Rifle. The Type C featured a center-mounted 37mm Gun M3, the same gun used in the M3/M5 Stuart Light Tanks.

A Water Weasel armed with a 75mm Recoiless Rifle. Photo: TankPorn of Reddit

WW2 Service

The Norwegian mission that the M29 was designed for never took place. This did not mean that time had been wasted on the vehicle, as it soon found use in multiple roles, in multiple theaters, and by multiple countries.

An American Weasel in Normandy, 1944. Photo:WW2 in Color

The United States used the vehicle extensively during World War Two. It was used in Italy, the Western Front, and even in the Pacific. It saw action during the Normandy landings, St. Lo, and the Battle of the Bulge. It proved its usefulness at the engagements on the Ruhr and Rhine, where it was able to cross the thick, sticky river mud. In the Pacific, it was used by the United States Marine Corps (USMC) at Iwo Jima and Okinawa, where it proved capable of crossing loose sand, and the harsh tropical island terrain where the Marine Corps’ jeeps wouldn’t dare venture.

The use of the M29 Weasel as a universal vehicle soon became clear to the Americans. They used it regularly as a light troop carrier and cargo hauler, and also as a mobile command center, ambulance, and to lay telegraph wires. One of its major attributes was its ability to cross minefields, as its low-ground pressure was often not enough to trigger the anti-tank mines. The ground pressure was still more than enough to trigger anti personnel mines which could easily split a rubber track.

An M29C in an ambulance role on the Rhine.

Service in the Commonwealth

The British and Canadian armies also used the Weasel in World War Two. Supplementing a number of LVT Buffalos, M29C Water Weasels of the 79th Armored Division were used by Commando troops in the Walcheren Operation. The 79th also used a number of the standard M29s to clear mines and other defensive devices.The Canadians made use of the Weasel’s semi-amphibious nature in their engagements in the flooded estuaries of Antwerp in 1944, and would go on to serve them through the Netherlands and into Germany.

After WW2

The Weasel remained in service after the Second World War. In 1946, there was a plan for the US Army to use the Weasel to rescue the victims of the C-53 Skytrooper crash on the Gauli Glacier but the Swiss Air Force managed to rescue the victims first. With the US Army, they would go on to serve in the Korean War.

French M29C in Vietnam.

In 1947, the French Army used the M29 in the First Vietnam war, where the 1er Régiment Étrangers de Cavalerie were equipped with the M29C variant. They armed them with multiple types of weapons, from the Chatellerault M1924/29 and Browning M1919 machine guns to 57mm recoilless rifles. The M29 would remain in service with French mountain troops and Gendarmerie as late as 1970.

Civilian Use

With a large surplus supply, the United States sold off large quantities of the M29 to various countries, including Sweden, France and Norway. Many Weasels served in scientific arctic expeditions, but their most famous use in civilian hands was at the 1960 Olympic Winter Games at Squaw Valley, California, USA.

The Automotive Company, Consolidated, sought to update the Weasel in 1960. They designed the ‘Sno T’rrain,” which was two Weasel chassis coupled together with fully enclosed canopies.

Today, there is a large community of Weasel collectors and restorers. As such, there are many running examples in private collections world wide.

Cargo Carrier M29 Weasel

Dimensions (L-W-H) 10′ 6” in x 5′ x 4′ 3”
(3.20 x 1.5 x 1.80 m)
Total weight 1.8 tons
Crew 1 driver, 3 passengers
Propulsion Studebaker Model 6-170 Champion 6-cylinder, 70hp
Speed (road) 36 mph (58 km/h)
For information about abbreviations check the Lexical Index

Links, Resources & Further Reading

The M29 on Military Factory
www.m29cweasel.com
www.studebaker-weasel.com

M551 Sheridan

U.S.A. (1965)
Light Tank – 1662 built

The Missile-Firing tank

The Sheridan was one of these developments tailored to explore a tactical theory and put it to the test. At the time the perpetual chase between armour and weaponry seen lost in favour or the new ammunition, and the tactical possibilities introduced by lighter missiles met US Army Ordnance specifications for a new light tank. The previous M41 was too heavy, had a short range and inadequate weaponry already, so lighter models like the T71 and T92 were tested. None were amphibious however, and after reports about the new Soviet PT-76, the XM551 was built and tested. To meet all conflicting requirements the new design showed a combination of an aluminium hull with a steel turret, to keep the weight down while providing buoyancy and the required level of protection. The vehicle had yet another remarkable feature with a 152 mm gun capable of firing the MGM-51 Shillelagh AT missile.

Development History

The task of the designers of the XM551 was daunting. Providing an amphibious tank (none were built since the specialized World War 2 LVT families and DUKW and SEEP) light enough to be airlifted seemed only possible with a small model build from light alloys, but at the same time, mobility and range were to be greatly enhanced and moreover the armament needed to be enough to knock-out a 1960s main battle tank. This squaring of the circle resulted in the Sheridan. Since a “normal” gun powerful enough for the task would have needed a long barrel, large turret, and hull, the solution was to use missiles instead, which provided their own velocity and could be launched from a simple tube. At the end the solution was so unusual it was called an “Armoured Reconnaissance/Airborne Assault Vehicle” but not a light tank.

XM551 Pilot

Design

Obviously the protection seemed to be sacrificed on this model. The aluminium hull and the steel turret could only hold against 0.5 inches fire (heavy MG) but remains vulnerable to grenade, ATGMs and mines. The hull was compartmented into lateral flotations screens, with a front “surfboard” made of wooden hinged folded layers. It could be deployed into a frontal sloping vertical surface, with canvas to cover the flanks, maintained by poles at the rear, sides, and high as the turret top. The system was directly taken from World War 2 DD tanks. The front “bow” comprised a plastic window for the driver which provided a mediocre visibility was later eliminated. The driver steered the tank blind, guided by the Commander towering above his cupola. In all, the tank was only 15.2 tons which was light enough to be airlifted by “heavy duty” helicopters like the Boeing Ch-47 Chinook and the Ch-58 Sea Stallion and most air transporters. There was sufficient buoyancy to allow the tank to swim at at 5.8 km/h (3.6 mph), rather than just sink like most MBTs to cross deep rivers. Therefore it was amphibious and NBC-proof, like the Soviet PT-76. This swimming characteristics, lightweight hull allowing air transportation combined with a top speed in excess of 70 kph gave an excellent strategic and tactical mobility, at least on the paper.

CH-54B carrying an M551 Sheridan tank.

The aluminium hull was entirely welded, with some cast elements at the front and rear. Armour thickness ranged from approx. 8 mm to 13 mm at the front. The Detroit Diesel (General Motors) 6V53T, 6 cylinder, turbocharged diesel gave indeed an output of 300 hp (220 kW), and a favourable power/weight ratio of 19.7 hp/tonne. The driver train reused standard roadwheels and tracks (five doubled rubber-clad roadwheels per side, suspended by torsion bars) but there were no return rollers and the drive sprocket and idler were both specific to this model. The crew of 4 comprised the driver, located in the center, with his own hatch and three vision blocks, and two headlights/blackout lamps protected by armoured covers. The commander, gunner and loader were all located in the center fighting compartment, in a rather cramped turret. The latter was relatively flat and was given extremely sloped sides to maximize the effective thickness of the armour. The commander cupola was located on the right hand side, and was given a cal.50 HMG ring mount. The loader’s hatch was located at his left. There were also two banks of height electrically fired smoke dischargers on each side.

XM-551 Pilot #12 at Fort Knox, Kentucky.  Mid 1960’s

The armament was remarkable as a lightweight solution which could deliver a potentially killer blow. The M81E1 Rifled cannon was a short barrel, able to fire either missiles or tailored ammunitions for fire support. Due to the unfavourable velocity ratio, only traditional HE rounds were fired, for infantry support, while the AP capability was entirely provided by the new Shillelagh missile system. The latter was developed in 1958 by Sperry and Ford Aeronautics (Later Martin Marietta) as the XM13, produced in 1964 as the MGM-51. It was 152 mm in diameter with the winglets folded, and 290 mm wingspan unfolded, with a solid-fuel rocket and a 15 pdr shaped-charge (6.8 kgs) warhead. Guided by infra-red signals it could fly at 1,060 feet (320 m) per second. This was sufficient to defeat 150 mm of RHA plate at a 60º angle at the range varying from 2000 to 3000 m depending of the models A, B or C. 88 194 of these were produced until 1971. It was also deployed by the M60A2 “Starship” and the first prototype of the MBT-70. This weapon was completed by a roof-mounted cal.50 M2 (1000 rounds) and a coaxial M73 LMG with 3000 rounds.

 

Production & Variants

Production started on 29 July 1966, and the Sheridan entered service in June 1967. In all 1,662 M551s were built between 1966 and November 2, 1970 for a total cost of $1.3 billion for the entire program. However problems with the M81 gun quickly showed, as cracks developed near the breech after intensive firing, later linked to the Shillelagh “key” running in a slot cut into the barrel. The modified M81E1 introduced a shallower slot and matching modification to the missile. Still, the gun was criticized for having too much recoil for the vehicle’s weight and frail construction. The blast was enough to lift-off the second and even third road wheels. Experimental 76 mm guns were also tried but never adopted.

The M551 in Action

Vietnam War

In June 1967, the first batch of Sheridans entered service with 1st Battalion, 63rd Armor Regiment at Fort Riley. At that time, the concept was ready to be battle tested in Vietnam although there was no immediate use for the cavalry unit. This came in late 1968 when General Creighton Abrams met with Colonel George S. Patton IV and his 11th Armored Cavalry Regiment (11th ACR Blackhorse) as despatched in Vietnam (and remained the only cavalry unit in service here). These tanks were evaluated by the 3rd Squadron, 4th Cavalry, and the 1st Squadron, 11th ACR from January 1969 to the fall of 1970. These suffered badly from mines and RPGs, always fatal contrary to the M48 “Patton”. Sheridans there assumed reconnaissance, night patrol and road clearing duties and totalled 39,455 road miles and 520 combat missions with a combat readiness of 81.3%. Reports were enough to decide to equip all other cavalry squadrons with this tank. However it was also detected that the caseless 152 mm main gun rounds used were easy to ignite when the tank was hit by a mine.

Sheridan M-551 and crew members of the 3rd Squadron, 4th Cavalry, Vietnam. Circa 1969

This was demonstrated in late 1969 when three out of the nine Sheridans of the 4th Squadron, 12th Cavalry detonated on mines when crossing a river near the DMZ, being total losses. On march 1971, five (11th ACR) were lost in a row by a Vietcong ambush operating RPGs. In all these cases, the Sheridan just “melted” due to the heat intensity and aluminium nature, gaining a sinister reputation. However their mobility was excellent in mud and in general all terrains. They were found very effective in infantry support, bursting M657 HE shell or the M625 canister round which launched a devastating bunch of flechette rounds, despite their slow reloading time. Their low ammunition stock was compensated by their combination with combination with ACAVs (M113s) that carried extra rounds.

MGM-51 Shillelagh Anti-tank miisile fired from M551 Sheridan light tank.

By May 1970, the 11th Armored Cavalry Regiment entered Cambodia. Most vehicles has been modified with a large steel shield (“ACAV set”) to protect the commander when firing the 12.7 mm HMG buttoned-up in his open cupola. The driver was given a modified rotating hatch and an extra layer of bolted steel was applied to the belly to protect against mines, but mostly protecting the front part of the belly due to weight issues. The 11th Cav. also participated in Operation Dewey Canyon II in support to ARVN Lam San 719 Operation, taking heavy losses in the process.

A C-130 delivering an M551 Sheridan tank using LAPES (Low Altitude Parachute Extraction System).

The 1980s

The Army began to retire the Sheridan in 1978. But due to the lack of suitable replacement some units like the 82d Airborne Division retained them until the 1990s (1996 for the 82 AD). Another task was found to keep them active: Doing the bad guys in training, modified to resemble mock T-72 and T-80s. These vehicles were active at the National Training Center at Fort Irwin, California in the 1980s. They were retired at the end of 2003, and either scrapped, ended as targets, given to collections or dumped into the sea. During the invasion of Panama (Operation Just Cause) in 1989, fourteen M551s were deployed, among which four were transported by C-5 Galaxys and ten air-dropped by C-130s (two Sheridans destroyed upon landing). They were attached to TF Bayonet (193rd Infantry Brigade) part of TF Gator, taking part on the attack on the Commandancia and later provided support to JSOC elements inside Panama City. Height fought at Torrijos-Tocumen Airport. Their performance received mixed reviews.

First Gulf War (1990s)

Fifty-one Sheridans were deployed by the 82nd Airborne Division during Operations Desert Shield and Desert Storm. Their role was limited to reconnaissance and possibly six or fewer Shillelagh missiles were fired on anti-tank guns or T-55s in operation, the only operational use of these ordnance among 88,000 missiles produced. These were deactivated after the war. Attempts to provide them a standard NATO 105 mm failed. In fact replacement came with the M1128 Mobile Gun System variant of the Stryker. So the Sheridan was perhaps the last of American light tanks. 

M551 Sheridan Links & Resources

The M551 Sheridan on Wikipedia

M551 Sheridan Specifications

Dimensions (L-W-H) 20’6″ x 9’2″ x 9’6″ ft.in
(6.29m x 2.81m x 2.94m)
Total weight, battle ready 15.2 tons (34 000 lbs)
Crew 4 (Commander, Driver, Loader, Gunner)
Propulsion Detroit 6V53T 6 cyl. supercharged diesel 300 hp (220 kW).
Top speed 43 mph (76 km/h) road, 3.6 mph water
Suspensions Torsion bars
Range 348 miles (560 km)
Armament Main: 152 mm (5.98 in) gun M81E1, 9 missiles, 20 roundsSec: 1 cal.50 M2 (12.7 mm)+ 1 cal.30 (7.62 mm) M73
Armor Aluminium & steel – Max 0.3 in (8 mm)
Production (all combined) 1662

Ramses II

 Egypt (2004) – Main battle tank – 425 conversions

The M60/T-54 Hybrid…

In November 1984, US firm Teledyne Continental Motors (now General Dynamics Land Systems) part of Chrysler Defence, was awarded a contract to upgrade the T-54 for the Egyptian Army, still in large stocks in its arsenal. Among the origins of this idea was the Israeli Tiran conversion, which seems quite satisfactory for Tsahal…

The original project was to be called T-54E (the “E” standing for Egypt) but was subsequently renamed Ramses II, from the most famous conqueror Pharaoh of Ancient Egypt, and third sovereign of the Nineteenth Dynasty. The first prototype was sent to Egypt for extensive firepower and mobility trials in January 1987, until late 1987. By 1989, a technical assistance agreement was signed with Teledyne Continental Motors for additional modifications in the process of more extensive Egyptian testings, commencing in the summer of 1990.

However by 1998, these additional upgrades had still not led to any production. This second phase, which took years to complete, was accompanied by much more modifications than originally planned (focusing solely on mobility and firepower), and ended with a tank which only superficially bears some resemblance to the T-54 and had in fact more in common with the M60A3, the most current Egyptian tank in service then.

Design

From the basic conversion idea, the Egyptians obtained, in the process of nearly twenty years, a completely new breed of MBT which focuses attentions of world’s experts about the feasibility of radical modern conversions (based on a design first drawn in 1946-47) of a main battle tank, much more demanding than for a specialized variant. Besides the chassis front and turret, everything else was taken from the M60A3 and tailored to fit in, resulting in a strange post-cold war hybrid which would have been unthinkable before the globalization.

Hull & Armour

The hull was at first not modified much, but to accommodate the less compact M60 engine, the rear part was lengthened almost by a meter, while the lower part of the chassis was completely modified to support smaller roadwheels, with consequently one extra pair. However the armour seems to receive little upgrades. It is unknown how much the NBC lining have been upgraded, but is collective and helped by overpressure. The amphibious capabilities seems to have been extended by better sealing. No ERA blocks provision had been made so far. However some armor protection has been added, and armored side skirts. A modern fire detection and suppression system was installed in the engine compartment, new final drives, fuel tanks, Blair Catton tracks, and a brand new air filtration system.

Turret & Armament

The new FCS is a SABCA Titan Mk.1, coupled with a modified Avimo TL10-T sight and laser range-finder with an integrated in-eyepiece CRT alphanumeric graphic display (ballistic computer). The fire-control system includes SABCA’s double digital processor, magnification night sight, atmospheric sensors, automatic attitude and associated controls.

HR Textron provided the gun and turret stabilization system. The main gun is the 105 mm M68 ordnance (common with M60A3s), but the original DT-10T breech is kept modified as well as the recoil system for a better fit into the turret. A muzzle reference system and the M60 day/night searchlight are mounted over the gun. IR vision periscopes are provided for the gunner and driver, while the commander have an image intensification system. The turret receive also a new storage basket and completely modernized communication systems. Banks of four electrically operated smoke dischargers are also mounted on each side for active protection.

Engine, Transmission, Drive train

The new power pack consists of a TCM AVDS-1790-5A turbocharged diesel (908 bhp) which have 80% commonality with the M60A3 powerplant. It is coupled to a Renk RK-304 transmission. New exhaust pipes are fitted on either side of the hull rear. The suspension is provided by General Dynamics Land Systems, with six Model 2880 in-arm hydropneumatic suspension units fixed on doubled M48-type roadwheels. The original idlers are kept, but the rear drive sprockets are new, and there are two standard track-return rollers per side. New US-patented tracks are replacing the old ones.

Production & Service

Egypt purchased spare parts for its large M60 fleet and in 1997, thirty M60 series engines from General Dynamics Land Systems ($5,943 million apiece), with more for the conversion of the T-54 fleet into Ramses-II MBTs. Eventually, the design was sanctioned by a full conversion of a first batch of 260 units in 2004/2005, followed by the set-up of a local conversion in an Egyptian tank plant, with some technology transfers. This second phase saw an additional 165 vehicles being locally converted.

By 2013, an addition conversion of some 160-180 more is planned. The overall weight of these converted tank is now 48 tons. With an estimated 700 M60A1, 1016 M60A3 in service, 1000+ US and locally-built M1 Abrams, and now these US-based conversions, the part of soviet armour in the Egyptian inventory has rapidly dwindled in the course of twenty years. The only known active engagement of the 400+ Ramses II in service is the actual events linked to the 2011 “arab spring”. Indeed, Israeli media reported that the 9th, 2nd, and 7th Divisions of the Army had been ordered into Cairo to restore order during the “revolution”.

Ramses II Specifications

Dimensions : 35.43/24.6 x 11.48 x 9.51 ft
(10.8 oa/7.5 m x 3.5 m x 2.9 m)
Total weight, battle ready 55 tons (11,000 lbs)
Crew 4 (commander, driver, gunner, loader).
Propulsion British Leyland diesel BL 40, 450-650 bhp, later BL 60, 695 bhp
Speed 48/30 km/h road/cross-country (29.82/18.64 mph)
Range/consumption 500 km (310.6 mi)
Armament One M48 105 mm (4 in) main gun
Coaxial 7.62 mm L8A1 (0.3 in) machine-gun
Armor Turret front 7.6 in, glacis 4.72 in, sides 1.37 in (195/120/35 mm)
Ammunition used Antipersonal HESH, armor-piercing APDS
Total conversions 425+

Links

The Ramses II MBT on Wikipedia
Additional pics

 

ZSU-57-2 Sparka

Soviet Union (1954)
SPAAG – approx. 2020+ built

The First Cold War Soviet SPAAG

The soviet ZSU-57-2 was the first soviet Anti-aircraft self-propelled artillery to come out after the short-lived and ill-fated ZSU-37. The denomination stands for stands for “Zenitnaya Samokhodnaya Ustanovka” (“anti-aircraft self-propelled mount”) followed by ’57’, the caliber in millimetres, and ‘2’ the number of gun barrels. It was the first mass-produced SPAAG in Soviet Union and the first of a long lineage complementary to the future SAM carriers. It was long into Soviet service (nicknamed Sparka or “pair”), until the early 1970s due to its crude targeting system, but soldiered for much longer under other banners worldwide. In all it was also declined into 13 versions and sold to 29 countries, and fought in at least 12 major conflicts, a list that will be perhaps completed as the vehicle is still operated by 16 countries today.

Soviet SPAAGs Lineage from World War 2

From the ww2 T-60-3 based on a T-60 light tank chassis, to the ZSU-72 and ZSU-37 SPAAGs, it appeared that both the speed, range and accuracy of the guns were no longer a match for the upcoming generation of jets fighters as it was not already for the latest piston-engine fighter bombers. The idea of using a light tank chassis was not either a good choice as it appeared to have poor maneuverability in difficult terrain and slow off-road speed when loaded by the weight of the mount. The very short career of the ZSU-37 which was written off in the 1950s already showed the way for improvements.

ZSU-37

The only available SPAAG in the meantime was the BTR-152A, which featured the quad 14.5mm KPV heavy machine guns ZTPU-4, or the ZPTU-2. Both were no more than the Soviet equivalent of the American M13-M14 Maxson quad. They had no sufficient protections for the operators, and of course no NBC protection whatsoever.

Development of the ZSU-76-2

Back in February 1946 already, Works No. 174 Design Bureau in Omsk joined forces with the Research Institute No. 58 in Kaliningrad (Moscow Oblast) with a T34 conversion with a quad 37 mm AA guns. The design was submitted to the Technical Council of the Ministry of Transport, which prefer to base a design on the latest chassis available, the T-54 Therefore the Research Institute No. 58 Design Bureau under the supervision of V.G. Grabin started the development of a twin 57 mm automatic AA gun based on the tracked 57mm S-60, in the spring of 1947. The first S-68 prototype was ready in 1948, was given S-79A four-wheel carriage but did not entered production.

The S-60-57mm which inspired the twin S68 mount. It was found that six towed batteries of this type coupled with a PUAZO-6 AA director and the SON-9 FC radar was more efficient than a battery of 4 vehicles, despite their superior firepower.

But this led to the ZSU-57-2 (Ob’yekt 500), fitted with a twin S-68 mount, and based on a reworked T-54 chassis. Following were a first prototype in June 1950, and second in December 1950, which all passed successful tests in January-March 1951. This included a crash course 500 km long and firing 2,000 rounds on targets. To get rid of teething problems and make more tests, six additional prototypes were delivered. Modifications included an increased ammunition load, but the improved driving systems for the S-68 were still not ready yet and delays ensured, with the final service tests occurring in December 1954. The ZSU-57-2 entered service eventually on 14 February 1955.

Design

Basically the soviet SPAAG uses a shortened T-54 chassis with four twin road wheels per side instead of five and a thinner armour. The second major characteristic was that the twin 57 mm S-68 was mounted in large, open-top and fully revolving turret. The compartimentation was classical, with the driver on the front, fighting compartment in the middle and engine compartment and transmission at the rear. This design also reused a maximum of parts from the T-54 in order to be kept cheap to produce, and maintain. To go more in details, the driver’s position was on left hand side, but moved forward and further to the left compared to the T-54.

He was given a single-piece hatch cover, opening left, two periscopic vision devices alternative to one TVN-1 infrared vision sight and infrared headlamp. Also in his compartment were stored parts and the fire-fighting equipment signal panel. Other differences included a G-74 direct current generator, 6-MST-140/STEN-140M accumulator batteries, automatic anti-aircraft sight of the plotter type with two collimators, and a 10RT-26E portable radio transceiver (right hand side turret interior) and TPU-4-47 intercom. Both were changed for newer models along production. For self-defence the crew was also given AK-47 assault rifles and a 26 mm signalling pistol.

“Sparka” blueprint.

Mobility

The V-54, 4-stroke, airless (mechanical)-injection, water-cooled 38.88 liter V12 diesel engine gave 520 hp (388 kW) at 2,000 rpm and it was mounted transversely to save space as in the T-54. The shorter chassis compensated for the turret weight, but overall the vehicle was 28.1 tonnes versus 36 for the T-54. Armour savings also added to the difference, as the vehicle was protected by 8-15 mm of armour, whereas the T-54 was protected by 120 mm of sloped armour at the front.

This gave the vehicle a 18.5 hp/tonne (13.81 kW/tonne) ratio versus 14.6 hp/tonne for the T-54 and top speed of 50 km/h (31 mph) on flat versus 48 kph for the T-54. It was also more agile, accelerated much faster, can carry more fuel (inside the hull 640l, external the right fender each 95l). The drivetrain was the same except for the lack of a twin rubber-tyred road wheels pair, each was given a torsion bar system, and hydraulic rotary shock absorber on the first and last unit. Front idlers, rear drive sprockets, no return rollers, large 90 links tracks which gave a ground pressure of 0.63 kg/cm2.

Protection

A meagre gain, tempered by a greater range (420 km) and the limitations of the original drivetrain. But this was fast, enough to shepherd the Armoured Units en route at full speed from strafing attacks. Of course the lack of armour was a liabilty in urban combat, which came later, and the vehicle was an easy prey for RPGs. The open-top turret prevented also a good servant protection both from snipers and shrapnells, not to mention the absence of any form of NBC protection. Details of the armour were as follows: 13.5 mm upper front (60°), 15 mm lower front, hull sides 13.5-15 mm, rear 8-10.6 mm, roof 15 mm, bottom 13.5 mm, turret sides 13.5 mm, mantlet 15 mm.

Armament

Detailed view of the twin S-68 guns of a Syrian or Egyptian ZSU-57-2 SPAAG which was captured by the Israeli army.

The trademark of this model was its boxy, roomy open-top turret, with rounded sides only 8 mm thick, resting on a ball-bearing race ring 1850 mm in diameter. When not in use, guns in the travel lock position, the turret can receive a tarpaulin with 16 plexiglass windows. The turret upper front had two small ports with armoured covers for the sights collimator. For the guns to operate, the target’s speed & direction (visual estimation) and range (sight and rangefinder) was entered into the sighting system by the sight adjuster located left-rear.

To fire, there were two loaders, left and right, that opened the breeches, and load the 4-rounds clips into the magazines manually and their travel seats had to be be stowed in clamps on the turret sides each time. The gunner located left hand side, middle, was to lay the gun and open fire with an electric trigger (both guns) or each one individually via foot pedals. This was operated via an electro-hydraulic drive, with a manual mechanical backup.

The twin S68 barrel and mount weighted as much as 4,500 kg. They had a recoil of about 325-370 mm. Their base model, the 57 mm S-60 AA autocannons were very much a Bofors-type with a longer barrel and larger bore. Each barrel is air-cooled gun barrel, 4365 mm long, and fitted with a muzzle brake. Traverse took 0.2°-36° per second and elevation −5° and +85° at 0.3-20° per second, propelled by a direct current electric motor and universal hydraulic speed gears with a mechanical manual backup. The maximal rate of fire was 210–240 fragmentation and armour-piercing tracer (AP-T) shells per minute, and practical rate was about 100-140 rpm at 1,000 m/s.

Polish ZSU-57-2, guns at maximal elevation.

Each 2.8 kg projectile (with the warhead and nitrocellulose powder charge) could reach 12,000 m in maximal elevation and range, although the effective range was 4 km (2.5 miles). Specifics of the HE-frag rounds used against flying targets meant their effective range was about 6.5 to 7 km. Against ground targets, BR-281 AP rounds were used. They can defeat 110 mm armour at 500 m or 70 mm armour at 2,000 m which was lethal against all light armoured vehicles and could be against the soft spots of some medium tanks. 300 rounds were carried, some stored in loaded clips in the turret, hull front, and the remainder are stored unclipped under the turret’s floor. Empty cases were extracted and conducted via a conveyor belt to a wire metal basket in the back of the turret.

A single HE-Frag shell was considered lethal against any aircraft of the time according to the Air Defence Research Institute No. 2, and this SPAAG was seen by most experts as the most powerful in existence at that stage, especially compared to its NATO rival, the M42 Duster.

Variants

Soviet variants:
ZSU-57-2 modernised twin S-68A autocannon, officially entered service with the Soviet Army in 1955.
Many ZSU-57-2 were converted into bulldozers after being removed from AA units at the beginning of the 1970s by army workshops. A steel closed superstructure replaced the turret and a BTS-55 bulldozer blade was added at the front.

-Cubans ZSU-57-2 had hanging flaps added to its track guards.
-Egyptian ZSU-57-2 were modernized and given a radar
-Finnish ItPsv SU-57 were given a machine gun mounted on the front of the turret.
-East German FAB 500U (Fahrausbildungspanzer) were converted driver training vehicles.
-North Korean versions were based on Type 59 chassis with many elements from the Chinese Type 80.
-Bosnian Serbs models converted to SPGs with overhead protection and ammunition crate welded on the glacis plate.

Chinese Type 80
The reference Chinese SPAAG which had the same turret as the ZSU-57-2, but wit the Type 59 twin anti-aircraft autocannon copy, and a chassis of Type 69-II MBT. It’s a heavier beast altogether, which will be scrutinized later in a standalone post.

Exports

Algeria (45, 1974), Angola (40, 1975), Cambodia, China (Type 80), Cuba (25, 1963), Egypt (100, 1960), Eritrea, Ethiopia (10, 1977), Hungary (24, 1967), Indonesia, North Korea (250 turrets ordered 1968-77 mated on local models), Mozambique (20, 1982), Somalia, Sudan, Syria (255, 1966), Vietnam (500, probably offered free), Finland (12, 1960, now retired), East Germany (129, replaced 1967, converted FAB 500U), Iran (100, 1966), Iraq (100+ Type 80s), Poland (129), Romania (60, 1965), Slovenia (12, 1991), Yugoslavia (100, 1963). The ZSU-57-2 was also tested Czechoslovakia and some captured ones used by the Croats and Israeli.

Croatian ZSU-57-2 in Vukovar war museum.

The ZSU-57-2 in Action

The list of conflicts where this SPAAG, either organically attached to armoured units or detached for specific operations is the following so far:
Vietnam War (1959–75), Six-Day War (1967), 1973 Yom Kippur War, Angolan Civil War (1975–2002), Sino-Vietnamese War (1979), Iran–Iraq War (1980–1988), Lebanon War (1982), First Persian Gulf War (1990–91), Yugoslav wars (1991–2001), which includes the Ten-Day War, Croatian War of Independence, Bosnian War, and Kosovo War, but also the Second Persian Gulf War (2003), following Invasion of Iraq and continuation war, and 2011 Syrian Civil War.

In Vietnam, these were used massively (as much as 500 ZSU-57-2s survived the war, now about 200 would be still in service) by the Vietnam People’s Army (VPA), first seen in the 1972 Easter Offensive (attached to the 201st and 202nd tank regiments), and later the Ho Chi Minh Campaign in 1975. Although they were used against US aircrafts it proved more effective against ground targets. Captured ones were allegedly used also by the South Vietnam Army for some time.

In the Middle East, the records of this SPAAGs are quite impressive, spanning decades, and starting with the 1967 Six Day War, 1973 Yom Kippour and continuation wars, operated by Egypt and Syria. Egyptian ones defended El-Arish airstrip but many were destroyed of captured on june, 6, 1967 by M48 Patton tanks of the 7th Armored Brigade. Captured ZSU-57-2 by the Israeli were used only until the end of the war. b

Others operated by the Syrians served in the 1982 Lebanon War, trying to shot down Israeli aircrafts over the Beqaa Valley. They were found again more useful against ground targets. In the Iran-Iraq war, these were operated by both camps as well as their copies Chinese Type 80s. They were found more successful when deployed together with ZSU-23-4s or 9K31 Strela-1 which passed on target information through their on-board radar against Iranian AH-1J Sea Cobra attack helicopters. Some of these shoot down two British Tornado in the First Persian Gulf War, over the Shaibah air base and severely damaged three others. They were seen again in action in the 2003 Invasion of Iraq.

Polish ZSU-57-2

In Syria, only 10 of these SPAAGs took part in the Spring of 2014 offensive and the fights at Harasta, Rif Dimashq Governorate probably limited to ground support only. In Yugoslavia, these were used as light batteries by Serbs and Montenegrins of the JNA, again, against ground targets. The Croatian forces captured two of these, and these were extensively used by the Serbs during 1999 NATO air raids (no less than 54 deployed). The Bosnian Serbs mounted improvised roof protections on theirs.

The ZSU-57-2 had some shortcoming through. Some were pretty obvious at the start, like the open-top turret. This was not a problem then as NATO’s rare SPAAGs were also all open-top. But from the 1970s new fully enclosed models appeared, that were also given modern FCS, radars, and allowed a full NBC protection. The second limitation of the model was its late adoption. At that stage, aviation technology and performance accelerated twin fold, and in terms of rpm and traverse speed only, this generation of SPAAGs was already obsolete and de facto in all subsequent operations frequently used to deal with ground target, or slow-moving helicopters and light aircrafts.

A modified Bosnian Serb ZSU-57-2 at a cantonment area in Zvornik, Republika Srpska, on February 28. 1996, during Operation Joint Endeavor.

Works No. 174 started a modernization programme started in 1957 but soon abandoned due to the development of more promising radar-guided SPAAGs with lower-bore cannons but much faster rate of fire. The absence of mechanical computing and reliance on visual sights made it only practical by day, accurate when idle (not on the move) and against relatively slow, low-flying objects. Probably its biggest limitation was its slow traverse, woefully inadequate against low-flying jets at full throttle. But when these big cannons hit their mark either by chance or marksmanship the result was almost certain. Just like the US SPAAGs of the first generation they were gradually found more useful in support of the infantry when raw firepower was needed on the spot.

Map with ZSU-57-2 operators in blue with former operators in red.

Sources

The ZSU-57-2 on Wikipedia
The ZSU-57-2 on Miliary Factory
Walkaround video of the ZSU-57-2
The ZSU-57-2 on Wikipedia

ZSU-57-2 Specifications

Dimensions (L-w-h) 6.22 (8.46 oa) x 3.27 x 2.71 m ()
Total weight, battle ready 28.1 Tons
Crew 6 (driver, cdr, gunner, sight adjusters, 2 loaders)
Propulsion V-54 wc 38.88 l V12 diesel 520 hp (388 kW)
Speed (land/water) 50/30 km/h (31 mph)
Range (road/off road) 420/320 km (on/off road)
Armament 2 x 57mm S68 autocannons
Armor 6-15 mm (0.25-0.55 in)
Total production 2020+

 

ASU-57

Soviet Union (1951) Airborne Tankette – Approx. 500 built

A Tankette for Airborne Operations

The soviet ASU-57 emerged from a 1946 specification for an airborne vehicle which can provide a mobile antitank support to the paratroopers. It had to be lightweight to fit in the cargo bay of the transport planes of the time, and be compatible with the parachute pallets maximum payload, and was to be armed with a 57 or 76mm gun. Two design bureaus were charged of the project Astrov (OKB-40) in Mytishchi and Kravtsev in Moscow. The first unveiled a derivative of the wartime light tanks like the T-40 and SU-76, and armed with the new 76mm gun D-56T tank gun. However, despite an only 3 mm armour it was still too heavy and was rejected. Anatoly Kravtsev’s bureau on the other hand presented the amphibious K-7 armed with Charnko’s 57mm anti-tank gun Ch-51. It was lighter but still not convenient enough for production.

ASU-57 – credits wikimedia commons

Development

In 1949, the project was relaunched, Nikolaj Astrov being given the task of marrying his model, made lighter, with the Ch-51 main gun, which showed better performances and was much lighter. Under the name of Ob.572, the new hybrid tankette was developed simultaneously as the light artillery tractor Ob.561 (AT-P) to lower the cost by commonality, and eventually after that all test phases were completed in 1949, was accepted into service in 1951 as the ASU-57 (denomination for a light SPG, and the caliber).

Paradrop sequence.

Design

The ASU-157 was originally designed to be air-dropped alongside troops from the cargo bay of the standard Antonov-12, by means of rocket-assisted parachute (PP-128-500 or P-7). The main gun Ch-51 was a development of wartime ZIS-2, but crossed with the improvements of the Ch-26 light AT gun. Only the first serie used this model, which was replaced by the Ch-51M with a much shorter double-baffle muzzle brake in 1957. It could fire the standard ZIS-2 57x480R AP rounds, but also the the BR-271 and O-271U rounds. 30 were in storage in the hull. To keep the cost as low as possible, the engine was derived from the GAZ-M-20 “Pobeda” civilian car, and most of the parts came from wartime light tanks like the SU-76 and T-40, including the wheeltrain and suspensions.

ZiS-2 SPB ammo range.

This comprised four ruberrized roadwheels, the latter being used as idler/tensioner, and front drive sprockets. The tracks were narrow, and the front part were supported by two return rollers, positioned on either side of the second roadwheel. Suspensions were simple, short torsion bars. The design was so compact, and made of welded and bolted aluminum plates, that the hull ended with 6 mm armour at the front, sufficient for small arms fire (in theory). It was completely open and left the crew unprotected over the shoulders, but with a good field of vision and easy access. Outside the crew of three, and despite its small dimensions, it was large enough to accommodate six more men and an improvized APC. All were equipped with an 10 RT-12 radio and TPU-47 intercom. In 1961, the vehicle was upgraded, receiving the R-113 and then R-120 radio, and the driver a TVN-2 night vision periscope.

The original 57 mm AT gun, model 1943.

Operational Service

The ASU-57 was the first successful soviet airborne tank design. In the 1930s, when airborne divisions were first set-up and pioneered following the definition of the deep battle concept, many air dropping solutions were tried, with amphibious and light tanks and tankettes, but all failed at the end. In the 1950s, when the ASU-57 was introduced, all airborne divisions received 54 vehicles each. Early tests were performed under the Tu-4 bomber wings. However at the end of the 1950s, only 245 ASU-57 were in service, and the gun, derived of a 1943 design, was seen as obsolete.

NATO airborne equivalent was the vastly superior 106 mm recoiless gun. The ASU-57 was kept in service for 20 years, before being phased out in the 1980s, and gradually replaced by the heavier ASU-85, as capacity in airlift cargo capacity was raised in parallel. The arrival of the latter was delayed by the new P16 parachute platform. The first large scale deployment occurred in the 1967 exercise Dniepr, with the 76th VDD. Outside the An-12, this model could be airlifted and dropped either by the Yak-14 the older An-8.

The only operational variant was the command staff vehicle ASU-57KShM, without gun but with additional radio and signals equipments. Prototypes were also tried, the BSU-11-57F/2T2 107 mm recoiless SPG, and the amphibious ASU-57P in 1951. MMZ built in total an estimated 500 vehicles until 1962 (exact production figures remains unknown).

ASU-57 and Mil Mi-8, the only helicopter which can carry this tank – credits wikimedia commons

Exports

The ASU-57 was also supplied to Warsaw Pact nations. 100 were ordered in 1961 and remained in service in Poland, at least until the beginning of the 1990s. In 1961-1962, 20 were delivered to GDR. Very little is known about the use of ASU-57 by Chinese forces. Another 200 taken from soviet depots were shipped in 1966 1967-1968 to DPRK. Others ASU-57s were also supplied to Egypt and according to some sources, used during the Six-Day War in 1967. According to Murakhovski, several dozen were delivered to Ethiopia during the War of the Ogaden in November 1977. These were used with Cuban forces in the battles around Areva and Jijiga, in particular at the rear of the Somali forces with the help of the Mi-6 landings. It was used also by Vietnam, and one source states that some took part on the Polisario war, with the assistance of Libya.

ASU-57 at the paratroopers museum, with the packed parachute system – credits wikimedia commons

These vehicles are preserved in various conditions at Kubinka (2), the Central Museum of the Armed Forces in Moscow, Museum of the History of airborne troops in Ryazan, a Private museum of art in the village of Elijah (2), the Museum amphibious combat vehicles of the 7th Guards Airborne Division in Novorossiysk, Base Petawawa Military Museum in Canada, the Military Museum Geydzhtaun base (Canada), Military Museum in Kaunas (Lithuania), and the US Army Museum in Aberdeen.

ASU-57 Related Links

The ASU-57 on Wikipedia
Additional informations on krasnayazvezda.com (Fr)

ASU-57 Specifications

Dimensions (L-w-h) 3.48 x 2.8 x 1.18 m (11.5 x 9.2 x 3.1 ft)
Total weight, battle ready 3.4 Tons
Crew 3 (driver, cdr, gunner)+6
Propulsion M-20E4 wc gas. 50hp (37.29 kW)
Speed (land/water) 45 km/h ( mph)
Range (road/off road) 250 km (160 mi)
Armament 1x Ch-51 57 mm gun
1x DTM 7.62 mm (0.3 in) MG, 2500 rounds or Heavy 12.7 mm DSHK AA MG – see notes.
Armor 6 mm (0.28 in)
Total production Approx. 500