AFV Modeller - Issue 12 - 2 - A Mortar Called Karl

AFV/12 Sept/Oct 03

15/8/03

5:17 pm

Page 12

The mortar seen under postwar Russian ownership in the 1943 type three tone camouflage. The hull is in the raised transport position and due to the missing track the vehicle appears to be lop-sided.

A mortar called Karl By Thomas Anderson The Second World War produced many

fortification system was not defeated by

covering of the fire position. Cross country

outstanding weapons, and just as many

these ‘wonder guns’.

mobility was limited, For any longer travel rail transport was preferred. For this

developments which ended ingloriously in the chaos of the lost war. The siege guns,

The Geräte 040 and 041, which would rise to

purposes special heavy railway carriages

which were developed before WW 1 to

fame under the name "Karl", were prime

were developed. The SP gun was hung

fight bunkers and fortifications,

examples. The OKH itself demanded such

between two of them, surely an imposing

undoubtedly belonged to this class of

self-propelled guns in 1937. Utilizing World

picture. For transportation in areas not

weapons. These heavy and heaviest

War I vintage developments, the firm of

attainable by rail, the SP guns were

artillery systems actually stood in complete

Rheinmetall delivered a 60 cm mortar, which

dismantled in four loads. These partial

contrast to the demands of modern mobile

fulfilled all expectations. The 70 to mortar

loads were carried on Culemeyer heavy

warfare.

had a barrel of 5 m length and was able to

duty flat-bed trailers, each SP gun one 24-

fire a 2,2kg to projectile up to 4,500 m.

wheel and three 16-wheel trailors were required. For each two guns a 35 ton

The construction of ever stronger

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fortresses at the beginning of the last

The weapon was built upon a self

crane and two 7 ton support cranes were

century involved the development of

propelled gun carriage of 60 ton weight.

carried along. Ammo supply was carried

"concrete busters". These high-trajectory

Originally a torpedo boat engine with a

by tracked ammunition tractors, two of

guns or mortars were fired at high angles

(throttled) performance of 580 HP was

them were allotted per mortar.

to hit bunker roofs from above, thus

installed. However, due to this throttling the

Seven mortars were manufactured with six

damaging it decisively. Hitler, being fond

engine had a very high oil consumtion and

being delivered to the troop, one SP gun

of big guns, demanded artillery systems of

corresponding wear. So later a diesel

remained with the manufacturer. Two

the utmost performance to fight the French

engine was installed. The SP gun reached

different undercarriages were produced,

Maginot line. However, the course of the

a travel speed of 10 km/h, this "marching

the first two mortars had 8 running wheels,

war showed that this incredibly large

capacity" was used only for immediate

the remaining five 11 running wheels.

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The mortar from the front in the museum hall.

The mountings of the entrenching tools are recognizable between the ladders.

inoperative for some time.

After reaching a firing position, firing

"Adam" and "Eva" in the middle section at

direction had to be aligned with the SP

Brest-Litovsk.

guns chassis because of the reduced side

"Adam" fired 16 rounds, "Eva" not even one.

There was no doubt that combat was far

traverse of only 2.5°. Then, the hull was

Her first grenade got stuck in the barrel, so

from being successful. Nevertheless, the

lowered by a lifting transmission, this

"Eva" had to start the long trip home to

1./833 was sent into action again in June

process lasted only 15 seconds. This was

Rheinmetall in Düsseldorf. However, the

1942 during the attack on the fortress

necessary since recoil strengths to had to

citadel of Brest-Litovsk, a fortification of

Sevastopol. And here the mortars showed

be carried through the hull itself.

only four square kilometers was heavily hit.

their full effect. The heavy bunker "Maxim

A veteran remembered: ‘Brick walls of two

Gorki" was shattered by "Thor" and "Odin."

The troop gave names to the guns, which

meters strength collapsed under the force

After this the two mortars ran short of

originally had only numbers:

of the concrete grenades, partially they

ammunition. Until the fall of the fortress no

SP gun I - "Adam", II - "Eva", III - "Odin", IV -

were pulverized. Concrete aims over two

ammo supplies reached the mortars. The

"Thor", V - "Loki" and VI - "Ziu". Towards end

meters thickness were penetrated by

battery leader summarized: ‘In action the

of the war "Eva" was renamed "Baldur."

direct hits. Complete bunkers were lifted

tanks (the motor carriages) suffered badly,

out of the soil’...

their lifting mechanism didn´t stand the permanent burden.... When fired with the

In January 1941 the schwere Artillerie Abteilung 833 was organized. During the

Both guns used in the area around

7th charge, the light concrete grenades

initial phase of Barbarossa the 1. battery

Lemberg fired only a few shots, simply

turned somersaults – well, bad luck, that!

with "Thor" and "Odin" saw action in the

because of the lack of worthwhile targets.

In total, however, little Karl performed

southern section at Lemberg, the 2. with

"Odin" broke its tracks, becoming

pretty well“.

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The insufficient ammunition supply, the

The photos

The three black and white photos were made available by S. Netrebenko, the

lack of heavy half tracks and the short

author took the color photos himself.

lifespan of the barrels - indeed much less

The only surviving mortar ‘Ziu’ is still on

than had been assumed - impeded further

display in the Kubinka museum. The three

use of the mortars. Personnel and material

black and white photos show it´s condition

expenditure was immense, surely another

shortly after end of the war, still in three

reason, that these interesting weapons

colour camouflage scheme. The vehicle

Essay Hptm. A.D. Taube, Soldat und

didn´t play any significant rôle in the further

seems to have been rather complete at

Technik 4/91

course of the war. The use of new 54 cm

this time. Today, it is stored in a hall being

Essay R. Böhm, Wehrtechnische

barrels instead of the 60 cm mortars to

protected against the elements. Sadly the

Monatshefte 5/59,

improve the range was only patchy as

entire engine area is missing including

there was simply never was enough

transmission, motor and driver´s position.

Sources

ammunition. The gun had eight lifting flanges. The hand rails of the galleries are visible here.

The left muffler. When moving, the mortars produced immense din. During movement, tank engine were started to disguise it´s location .

The entire running gear was painted black by the museum staff.

A view to the gun carriage. To both sides ‘storage boxes’ were attached, their purpose is unknown although they may have been deflector panels for the exhausts.

14 The spring loaded deflector in deployed position.

The steps up to the rear galleries and transportation flange.

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The idler wheel at the stern shows a large tension adjustment device.

When transported via rail the loosely hanging track was secured by these winches.

A view to the front deck of the vehicle showing the manual winch could be used for lowering of the hull in emergency.

The 60 cm mortar. The large hand wheel was used by the K1 for the preadjustment of the elevation. The actual crank work was done by two men at the rear of the gun carriage. The K1 could then adjust the elevation exactly over a precise gear (the smaller hand wheel).

The same deck and cover plate.

The rear deck with loading tray.

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This cardan shaft elevated the mortar.

The (missing) periscope base for the K1 was installed here.

A further view to the double hand wheel.

This view shows the pattern of the step next to the breech.

The right side of the mortar, note the casting number on the gun carriage.

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The massive breech with partially open breech block.

The rear of the breech.

The breech and ramming mechanism.

The back of the chassis with engine access hatches.

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The gun carriage was of riveted construction.

Here the layout of the traverse gear is again visible. The recuperator bars are missing.

The mortar´s mighty barrel.

Notice the bracket under the breech opening.

The elevation drive terminates at the rear of the carriage

The left front side of the gun carriage.

This view below the barrel shows the interior of the gun carriage.

The entire engine area is empty. Unfortunately the engine deck covers are missing, too. The engine fan was accommodated in the rear section. Notice the bulge in the hull wall where it located.

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The front of the recuperator housing. only the left hand cover is original. The loading trolley balanced over the open engine compartment.

The front of the gun carriage. The loading trolley seen from the other side

The head of the ram rod on the loading tray.

With the gun carriage back in the recoil position we can see the front of the carriage and down to the hull floor.

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With this gear drive the narrow side traverse was operated.

The rear of the ram rod.

The elevating gears under the gun carriage and the torsion bars across the hull floor.