Sturmtiger

1. Lead

The Sturmtiger was one of the most extraordinary armoured vehicles of the Second World War: a 65-tonne assault gun built on the chassis of the Tiger I heavy tank and armed with a 380 mm rocket mortar — a weapon so large that its projectile weighed about 350 kg, more than three adult men.

Only 18 Sturmtigers were built, in 1944 and 1945, and they were designed for a single purpose: to demolish fortified buildings and strongpoints in street fighting, where no ordinary gun was powerful enough. The Sturmtiger fired a rocket-propelled shell that could smash through metres of concrete and collapse an entire building, and its crews fought in the Warsaw Uprising, in the Ardennes offensive and in the defence of the Rhine in 1945.

It was slow, it carried only 14 rounds of ammunition, and its great gun took minutes to reload — but at close range, against a fortified position, there was no more destructive weapon in the German Army. Two Sturmtigers survive today, in museums in Germany and Russia, and the vehicle remains a symbol of the desperate improvisation of Germany’s last year of war.

2. Key Facts

Type	Heavy assault gun / assault mortar carrier
Origin	Germany
Designer	Alkett (based on the Tiger I chassis by Henschel)
Manufacturer	Alkett, Berlin-Spandau
In service	1944–1945
Produced	August 1944–March 1945; 18 built (plus 1 prototype)
Weight	About 65 tonnes
Length	6.28 m (hull); 6.82 m (overall, with gun)
Width	3.57 m
Height	2.85 m
Crew	5 (commander, gunner, loader, driver, radio operator)
Armour	150 mm front hull; 82 mm superstructure sides; 62 mm superstructure front (approximate)
Main armament	38 cm Raketenwerfer 61 L/5.4 rocket mortar (380 mm)
Secondary armament	One 7.92 mm MG 34 machine gun
Ammunition	14 rounds of 380 mm rocket ammunition
Engine	Maybach HL230 P45 V-12 petrol, 700 hp
Top speed	About 40 km/h on road
Range	About 120 km on road (estimated)
Maximum range of gun	About 5,650 m

3. Background and Development

The Problem of Street Fighting

The Sturmtiger was born of the German Army’s experience of street fighting on the Eastern Front. At Stalingrad in 1942–43, German infantry discovered that their tanks and assault guns could not destroy the fortified buildings in which Soviet soldiers held out: the 75 mm gun of the Sturmgeschütz III and the 88 mm gun of the Tiger could punch a hole in a wall, but they could not collapse a building, and the Soviet defenders simply moved to another room.

The German Army concluded that it needed a weapon that could deliver an enormously heavy explosive charge at short range, and in 1943 the Army’s weapons office ordered the development of an assault mortar — a vehicle that could fire a shell heavy enough to demolish a building in a single hit.

The result was the Sturmtiger, which was based on the most heavily armoured chassis available, the Tiger I, and armed with a weapon that had originally been designed for the German Navy: a 380 mm rocket mortar, adapted from the depth-charge launcher of the Kriegsmarine.

From Naval Mortar to Assault Gun

The weapon chosen for the Sturmtiger was the 38 cm Raketenwerfer 61, a rocket mortar that fired a projectile weighing about 350 kg, of which about 125 kg was explosive. The projectile was so heavy that it had to be loaded with a crane, through a hatch in the roof of the fighting compartment, and the gun could only be loaded at a low elevation.

The first prototype was built by Alkett in Berlin in 1943, on a Tiger I chassis, and it was demonstrated to Hitler in October 1943. Hitler was impressed, and he ordered the vehicle into production, but the production was slow: the Tiger I chassis was in short supply, because Tiger production was ending and the factories were switching to the Tiger II, and Alkett had to use a mixture of new and rebuilt Tiger chassis.

The first production Sturmtigers were delivered in August 1944, and production continued until March 1945, by which time 18 vehicles had been built, along with the prototype.

A Weapon Looking for a Battle

The Sturmtiger was designed for the street fighting of the Eastern Front, but by the time it entered service, the German Army was retreating on all fronts, and the vehicle was used wherever a heavy assault gun was needed. Its first combat was in the Warsaw Uprising of August 1944, where two Sturmtigers were sent to crush the Polish resistance in the city.

After Warsaw, the Sturmtigers were organised into three independent companies — Sturmmörserkompanie 1000, 1001 and 1002 — each of which was supposed to have 14 vehicles, but which in practice never had more than a handful. The companies fought in the Ardennes, on the Western Front and in the defence of the Rhine, and the last Sturmtigers were destroyed or abandoned in the Ruhr pocket in April 1945.

The vehicle’s career was short and its numbers were tiny, but its firepower was so great that it is still remembered as one of the most powerful armoured vehicles ever built.

4. Design

The Tiger Chassis and the Armoured Superstructure

The Sturmtiger was built on the chassis of the Tiger I heavy tank, which gave it the thickest armour of any German assault gun. The Tiger’s turret was removed, and in its place Alkett built a large, boxy superstructure of welded armour plate, up to 150 mm thick at the front, which housed the rocket mortar and its crew.

The superstructure was so tall and so heavy that the vehicle’s centre of gravity was high, and the Maybach HL230 engine, which had already struggled with the 57-tonne Tiger, now had to move 65 tonnes. The vehicle’s top speed was about 40 km/h on a road, and much less cross-country, and its range was only about 120 km, which meant that it needed constant refuelling.

The Sturmtiger’s armour was its greatest strength: at the ranges at which it fought, in street fighting, it was almost immune to the anti-tank weapons of the infantry it faced.

The 380 mm Rocket Mortar

The Sturmtiger’s gun was the 38 cm Raketenwerfer 61 L/5.4, a short-barrelled rocket mortar that fired a projectile 380 mm in diameter and about 1.5 metres long. The projectile weighed about 350 kg, of which about 125 kg was high explosive, and it was propelled by a rocket motor that burned for a short time after leaving the barrel.

The gun had a maximum range of about 5,650 metres, but it was normally fired at ranges of a few hundred metres, where its accuracy was sufficient and its effect was devastating. The projectile’s flight was slow and its trajectory was high, and the gun’s crew could watch the shell arc towards its target.

The weapon’s greatest weakness was its rate of fire: the projectile was so heavy that it had to be loaded with a crane, and the gun could only fire about one round every few minutes. The vehicle carried only 14 rounds, which meant that it could only fight for a short time before it had to be resupplied.

Crew, Loading and Limitations

The Sturmtiger’s crew of five worked in a cramped fighting compartment dominated by the great mortar and its ammunition. The commander and the gunner sat on the left of the gun, the loader and the radio operator on the right, and the driver sat in the front of the hull, as in the Tiger.

Loading the gun was a laborious process: the projectile had to be lifted by a crane mounted on the roof, swung into position over the breech, and then rammed home by the loader, a process that took several minutes and that left the crew exhausted.

The vehicle’s secondary armament was a single 7.92 mm MG 34 machine gun, mounted in the front of the superstructure, which was the crew’s only defence against infantry at close range. The Sturmtiger’s limitations were severe: it was slow, it was short-ranged, it carried little ammunition, and it was so heavy that it broke bridges and bogged down in soft ground.

But for its intended purpose — the demolition of a fortified building at close range — it had no equal.

5. Variants

The Production Vehicles

Variant	Years	Key features	Production
Prototype (Sturmmörserwagen 606/4)	1943–1944	Tiger I chassis; 380 mm mortar; tested and demonstrated to Hitler	1
Sturmtiger (production)	1944–1945	Alkett superstructure; 380 mm Raketenwerfer 61; 14 rounds; 65 tonnes	18
Sturmtiger with rebuilt chassis	1944–1945	Some vehicles built on rebuilt Tiger I chassis returned from the front	Included in the 18

The Sturmtiger was produced in a single variant, and the 18 production vehicles were essentially identical, although they differed in small details. Some were built on new Tiger I chassis, and others on chassis that had been returned from the front for rebuilding, and the two groups can be distinguished by small differences in the hull and in the running gear.

The prototype, which was built in 1943 and demonstrated to Hitler in October of that year, was retained for trials and did not see combat. No other version of the Sturmtiger was built, although the German Army considered a version armed with a different weapon, and although Alkett proposed a Sturmtiger based on the Tiger II chassis, neither project went beyond the drawing board.

The vehicle’s production ended in March 1945, when the Alkett factory was overrun and when the supply of Tiger chassis ran out. The 18 production vehicles were delivered over seven months, from August 1944 to March 1945, at a rate of only two or three a month, and the slow rate of production is itself a measure of Germany’s industrial collapse in the last year of the war.

The Three Sturmmörser Companies

The 18 Sturmtigers were organised into three independent companies, Sturmmörserkompanie 1000, 1001 and 1002, each of which was authorised to have 14 vehicles but which never received its full complement. Sturmmörserkompanie 1000 was formed in August 1944 and fought in the Warsaw Uprising and then on the Western Front. Sturmmörserkompanie 1001 was formed in September 1944 and fought in the Ardennes and in the defence of the Rhine.

Sturmmörserkompanie 1002 was formed in late 1944 and fought in the Reichswald and in the Ruhr pocket. The companies were independent units, attached to armies and army groups as needed, and they were supported by supply columns that carried the enormous 380 mm projectiles.

The organisation was never completed: the companies fought with four, six or eight vehicles at most, and the shortage of ammunition and of spare parts meant that the number of vehicles available for combat was often smaller still.

6. Operational History

Warsaw, August–October 1944

The Sturmtiger’s combat debut came in the Warsaw Uprising, which began on 1 August 1944, when the Polish Home Army rose against the German occupation of the city. Two Sturmtigers were sent to Warsaw, where they were used to demolish the buildings in which the Polish resistance held out.

The effect was devastating: a single 380 mm shell could collapse a building and kill everyone inside it, and the Polish fighters, who had no weapon that could stop a 65-tonne armoured vehicle, could only watch as their strongpoints were destroyed one by one.

The Sturmtigers were used in the fighting in the Old Town and in the city centre, and they were credited with the destruction of several fortified buildings. The uprising was crushed by October 1944, at the cost of about 200,000 Polish civilian lives, and the Sturmtiger’s part in it — the deliberate demolition of buildings full of people — is one of the darkest episodes in the vehicle’s history.

The Ardennes and the Western Front, 1944–1945

After Warsaw, the Sturmtigers were sent to the Western Front, where they fought in the Ardennes offensive of December 1944 and in the defensive battles that followed. In the Ardennes, the Sturmtigers of Sturmmörserkompanie 1001 were used against American positions in the villages and towns of the Ardennes, where their great shells could demolish buildings that ordinary artillery could not.

The fighting was in winter, in snow and mud, and the Sturmtigers, which were already slow and short-ranged, struggled to keep up with the advance. Several were lost to breakdowns and to lack of fuel, and at least one was destroyed by American artillery.

The Ardennes offensive failed, and the Sturmtigers retreated with the rest of the German Army to the Rhine, where they were used in the defence of the river crossings in the spring of 1945. The Sturmtigers’ part in the Ardennes was small, because only a handful were available, but their great shells, which could demolish a building that had resisted artillery fire for days, made an impression on the American soldiers who faced them, and the Sturmtiger is remembered in the Ardennes as one of the most feared German weapons of the offensive.

The Defence of the Rhine and the Ruhr, 1945

The Sturmtiger’s last battles were fought in the spring of 1945, on the Rhine and in the Ruhr, where the German Army was making its last stand in the west. The vehicle had been designed for the street fighting of the Eastern Front, but it ended its career in the west, firing its great shells at the bridges of the Rhine and at the American infantry in the towns of the Ruhr.

The two battles described below — Remagen and the Ruhr pocket — show the Sturmtiger at its best and at its worst: at Remagen, its shells were powerful enough to damage a bridge, but too few to destroy it; in the Ruhr, its shells were powerful enough to demolish a building, but too few to stop an army.

The Sturmtiger’s last months are the story of a weapon that was too powerful for its own good, and too few to matter.

Remagen and the Rhine Crossings

In March 1945, American forces captured the Ludendorff Bridge at Remagen intact, and the German Army rushed every available weapon to the Rhine to try to destroy the bridge and to stop the American crossing. The Sturmtigers were among the weapons sent to Remagen, and they fired their great shells at the bridge and at the American positions on the far bank.

The shells were powerful enough to damage the bridge, but they were too few and too inaccurate to destroy it, and the bridge remained in American hands until it collapsed on 17 March 1945, ten days after its capture. The fighting at Remagen showed the Sturmtiger’s limitations: a weapon that could fire only once every few minutes, and that carried only 14 rounds, could not stop an army, however powerful each individual shell was.

The Sturmtigers withdrew from the Rhine and fought their last battles in the Ruhr pocket, where the German Army Group B was encircled by American forces in April 1945.

The Ruhr Pocket and the End

In the Ruhr pocket, the last Sturmtigers fought in the street fighting in the towns of the Ruhr, where their great shells were used against American infantry in fortified buildings. The fighting was desperate and confused, and the Sturmtigers, short of ammunition and of fuel, could do little to change the outcome.

The German Army Group B surrendered on 21 April 1945, and the surviving Sturmtigers were destroyed by their crews or captured by the Americans. One Sturmtiger was captured intact by American forces and shipped to the United States for trials, and another was captured by the Soviet Union and taken to the Kubinka testing ground, where it remains today.

The vehicle’s career had lasted less than a year, and only 18 had ever been built, but its firepower had made an impression on everyone who had seen it, friend and foe alike. The last Sturmtigers were abandoned in the Ruhr when their fuel ran out, and their crews, who had fought for less than a year, surrendered with the rest of Army Group B, ending the vehicle’s short and violent career.

7. Performance and Specifications

Specifications

Specification	Sturmtiger
Main gun	38 cm Raketenwerfer 61 L/5.4 (380 mm rocket mortar)
Projectile weight	About 350 kg (about 125 kg of explosive)
Maximum range	About 5,650 m
Rate of fire	About 1 round every few minutes (loading by crane)
Ammunition carried	14 rounds
Armour (front hull)	150 mm
Armour (superstructure front)	62 mm (approximate)
Armour (superstructure sides)	82 mm
Weight	About 65 tonnes
Engine	Maybach HL230 P45, 700 hp
Power-to-weight	About 10.8 hp per tonne
Top speed (road)	About 40 km/h
Range (road)	About 120 km (estimated)
Crew	5
Number built	18 (plus 1 prototype)

The table shows the Sturmtiger’s essential character: a vehicle that sacrificed everything — speed, range, ammunition capacity and rate of fire — for the sake of a single enormous shell. Its power-to-weight ratio of about 10.8 hp per tonne was poor even by the standards of the Tiger, and its road range of about 120 km meant that it could not operate far from its supply columns.

The gun’s maximum range of about 5,650 metres was impressive on paper, but the weapon was almost never fired at such ranges, because its accuracy at long range was poor and because its purpose was close-range demolition. At the ranges at which it was actually used — a few hundred metres — the Sturmtiger’s shell was the most powerful weapon carried by any armoured vehicle of the war.

The figures also show the Sturmtiger’s cost: a vehicle that weighed 65 tonnes, that carried only 14 rounds and that could fire only once every few minutes was an extravagant use of steel, of fuel and of men, and the German Army could afford only 18 of them.

Comparison with Other Assault Guns

Compared with the other German assault guns of the war, the Sturmtiger was an extreme case. The Sturmgeschütz III, the workhorse of the German assault artillery, weighed about 24 tonnes, carried a 75 mm gun, and was produced in more than 10,000 examples; the Sturmtiger weighed 65 tonnes, carried a 380 mm mortar, and was produced in 18 examples.

The Brummbär, the German heavy assault gun armed with a 150 mm howitzer, was the Sturmtiger’s closest relative: it was also designed for street fighting, it was also built on a tank chassis, and it was produced in about 300 examples.

The Sturmtiger’s shell was more than twice as heavy as the Brummbär’s, and its destructive effect was far greater, but the Brummbär could fire far more often, could carry far more ammunition, and was far cheaper to build. The comparison shows why the Sturmtiger remained a curiosity: it was a weapon that did one thing supremely well, and almost everything else badly.

8. Operators

Germany Alone

The Sturmtiger was used only by Germany, and only by the German Army. It was issued to the three independent Sturmmörser companies, which were Army units, and it was never exported, never licence-built and never used by any other country during the war.

The vehicle’s small numbers — 18 built — and its specialised purpose meant that it was never a weapon that could be shared with Germany’s allies, and by the time it entered service, Germany’s allies were themselves collapsing or changing sides. The Sturmtiger was also never used by the Waffen-SS, although SS units fought alongside the Sturmmörser companies in Warsaw and in the Ardennes.

The vehicle’s crews were Army soldiers, trained at the Alkett factory and at the artillery school, and they were among the most specialised crews in the German Army, because no other vehicle required the handling of a 350 kg projectile.

The Sturmmörser companies were among the smallest units in the German Army, with only a handful of vehicles each, but their firepower was greater than that of an entire artillery battalion, and their crews were treated as specialists, with extra pay and with priority for supplies.

Captured Vehicles

After the war, the surviving Sturmtigers were taken for trials by the Allies or preserved in Germany. The United States captured at least one Sturmtiger intact and shipped it to the Aberdeen Proving Ground in Maryland, where it was tested and then displayed at the museum, but that vehicle has not survived to the present day.

The Soviet Union captured another Sturmtiger and took it to the Kubinka testing ground near Moscow, where it remains on display today. A third Sturmtiger, which had been used for trials in Germany, was preserved at the Deutsches Panzermuseum in Munster, where it is now one of the museum’s most popular exhibits.

The vehicles were studied by Allied engineers, who were impressed by the size of the weapon and by the thickness of the armour, but who concluded that the vehicle was a dead end: a weapon that was too slow, too heavy and too specialised to be worth copying. The Soviet Union did not copy the Sturmtiger, and neither did the United States or Britain.

9. Legacy and Influence

The Most Powerful Shell of the War

The Sturmtiger’s legacy is the sheer scale of its weapon. No other armoured vehicle of the Second World War carried a gun as large as the Sturmtiger’s 380 mm mortar, and no other vehicle could deliver as much explosive in a single shell.

The vehicle’s 350 kg projectile, with about 125 kg of explosive, was heavier than the shells fired by the battleships’ secondary guns, and its effect on a building was comparable to that of a small aerial bomb. The Sturmtiger is therefore remembered as an extreme: the largest gun ever mounted on a tank chassis in the Second World War, and a weapon that showed how far the German Army was willing to go to solve the problem of street fighting.

The vehicle’s fame is out of all proportion to its numbers — 18 vehicles, less than a year of service — and it is a reminder that a weapon does not need to be numerous to be famous.

A Cautionary Tale

The Sturmtiger is also a cautionary tale about the limits of specialisation. It was designed for a single purpose — the demolition of fortified buildings — and it did that purpose supremely well, but it could do almost nothing else.

It was too slow to keep up with an advance, too short-ranged to fight in open country, too slow to fire to be useful in a battle of manoeuvre, and too expensive to build in numbers that mattered. The German Army’s decision to build it, at a time when it was short of tanks, of fuel and of men, is often cited as an example of the misallocation of resources in the last year of the war.

The Sturmtiger’s story is therefore not only the story of a remarkable weapon, but also the story of a regime that, in its last months, built weapons for the war it wished it was fighting, rather than for the war it was actually losing.

10. Surviving Examples

The Kubinka Sturmtiger

Two Sturmtigers survive today, and the better known of the two is the vehicle at the Kubinka Tank Museum near Moscow, in Russia. The Kubinka Sturmtiger was captured by the Soviet Union in 1945 and taken to the Kubinka testing ground, where it was tested by Soviet engineers and then preserved in the museum’s collection.

It is displayed in the museum’s hall of German armoured vehicles, alongside the Tiger I and other German tanks captured on the Eastern Front, and it is one of the most photographed vehicles in the museum, because of the extraordinary size of its gun. The Kubinka vehicle is in good condition, although it is not in running order, and it is one of only two Sturmtigers in the world.

For visitors to Russia, it is the easiest Sturmtiger to see, and it is displayed with its great 380 mm mortar pointing at the visitor, a sight that conveys the weapon’s scale better than any photograph.

The Munster Sturmtiger

The second surviving Sturmtiger is at the Deutsches Panzermuseum in Munster, Germany, where it is one of the museum’s most popular exhibits. The Munster vehicle was used for trials in Germany after the war and was preserved by the German Army before being transferred to the museum.

It is displayed in the museum’s hall of Second World War vehicles, where visitors can walk around it and see the great mortar, the crane on the roof and the thick armour of the superstructure. The Munster Sturmtiger is in good condition and is regularly maintained by the museum’s staff, and it is the only Sturmtiger on display in western Europe.

For most visitors, the Munster museum is the easiest place to see a Sturmtiger, and the vehicle’s presence there — in the country that built it — is a reminder of the extraordinary lengths to which the German war industry went in the last year of the war.

Frequently Asked Questions

What is the Sturmtiger?
The Sturmtiger was a German heavy assault gun of the Second World War, built on the Tiger I tank chassis and armed with a 380 mm rocket mortar. Only 18 were built in 1944–45.

How big was the Sturmtiger’s shell?
The Sturmtiger’s projectile weighed about 350 kg, of which about 125 kg was explosive. It was the largest shell fired by any armoured vehicle of the Second World War.

How many Sturmtigers were built?
Eighteen production Sturmtigers were built between August 1944 and March 1945, plus one prototype built in 1943.

Where did the Sturmtiger fight?
The Sturmtiger fought in the Warsaw Uprising of August 1944, in the Ardennes offensive of December 1944, and in the defence of the Rhine and the Ruhr pocket in 1945.

Why were so few Sturmtigers built?
Because the Tiger I chassis was in short supply, because the vehicle was expensive and specialised, and because the war ended before production could be expanded. Only 18 were completed before the Alkett factory was overrun in March 1945.

Where can I see a Sturmtiger today?
At the Kubinka Tank Museum near Moscow in Russia, and at the Deutsches Panzermuseum in Munster in Germany. These are the only two surviving Sturmtigers in the world.

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Sources

1. Wikipedia, “Sturmtiger” — production of 18, specifications, Warsaw and the Ardennes.
2. Thomas L. Jentz and Hilary L. Doyle, Germany’s Tiger Tanks: Tiger I and Tiger II (Schiffer, 2000) — the Tiger chassis and Alkett production.
3. The Tank Museum, Bovington, “Sturmtiger” — the vehicle’s design and surviving examples.
4. Deutsches Panzermuseum Munster, “Sturmtiger” — the Munster vehicle and its history.
5. Kubinka Tank Museum, “Sturmtiger” — the Kubinka vehicle captured in 1945.
6. Wolfgang Schneider, Tigers in Combat (Stackpole Books, 2004) — the Sturmmörser companies and their combat record.