The Panzerkampfwagen IV (PzKpfw IV), more commonly
referred to as the Panzer IV, was a tank developed by Germany and
used extensively in World War II. It was designed initially as an
infantry-support medium tank (begleitwagen, mittleren panzer), to
work in conjunction with the anti-tank Pzkpfw III. Later in the
war, it was up-gunned and up-armored, and took over the
tank-fighting role while Panzer IIIs were either put into infantry
support duties or converted into other vehicles. The Panzer IV was
the most common German tank of World War II, and was used as the
base for many other fighting vehicles, such as tank destroyers and
flak platforms. The Panzer IV has the distinction of being the
only German tank to remain in continuous production throughout all
of WWII, with over 9,000 produced from 1939 to 1945.
The Panzer IV was the workhorse of the German tank
corps, being produced and used in all theatres of combat
throughout the war. The design was upgraded repeatedly to deal
with the increasing threats from enemy forces.
On January 11, 1934, following specifications laid
down by Heinz Guderian, the Army Weapons Department drew up plans
for a medium tank with a maximum weight of 24,000 kg and a top
speed of 35 km/h. It was intended in a support and anti-infantry
role, using a low-velocity, large-caliber gun firing
high-explosive shells. It was not required to deal with enemy
tanks on equal terms.
Krupp, Rheinmetall, and MAN all produced
prototypes, which were tested in 1935. As a result of the trials,
the Krupp design was selected for full-scale production. The first
Panzer IV A came off the assembly line in October of 1937, with a
total of 35 being produced over the next six months.
Between 1937 and 1940, attempts were made to
standardize parts between Krupp's Panzer IV and Daimler-Benz's
Panzer III. The Panzer IV featured a relatively crude leaf spring
suspension, unlike the then-new torsion bar suspension system on
the Panzer III. There were several proposals to upgrade the
suspension over the years, but none left the drawing board as the
Germans dared not interrupt Panzer IV production. There was some
resistance to using torsion bar suspensions; as late as the
Panther tank design, simpler leaf springs were still being
considered.
The Panzer IV was originally intended principally
to deal with infantry and fortifications, while the Panzer III
dealt with enemy armored units. To this end it was equipped with
the 75 mm KwK 37 L/24 gun, which was effective against soft
targets but lacked much armor penetration. It had poor accuracy,
because the barrel was short (1800 mm), giving a low muzzle
velocity. Firing a panzergranate 39 round the muzzle velocity was
430 m/s, penetrating 40 mm of 30° steel plate at 700 m. For
comparison the L/48 gun has a barrel 3600 mm long. The length of
any barrel of a gun described in the L/x form can be found be
multiplying the x by the caliber in mm.
During the invasion of France the Panzer IV did
face tank-to-tank combat, the L/24 was found effective against the
French Renault and Somua tanks, but notably useless when fired at
either the Char Bl or the British Matilda with its front armor of
60 mm. This combat weakness was noted again in Africa later in
1940 during the fighting around Sidi Barrani and then Tobruk.
In March 1941 a prototype Panzer IV Ausf D was
fitted with a Krupp 50 mm L/60, the same type of gun as the Panzer
III. However the Panzer III was already unable to deal with enemy
tanks at long range. The prototype did not enter production. Krupp
already had a 75 mm L/40 which had 175% better penetration than
the L/24. In obedience to the Waffenamt dislike of an overhanging
gun this was shortened to produced the 75 mm KwK L/34.5. It was
fitted in a single prototype in December, but the reduced
performance with the barrel changes and the failure to developed
the promised Triebspiegelgeschoss (tungsten, discarding sabot)
round again meant that no production variants were made.
In June 1941 the invasion of the Soviet Union
introduced the German tanks to their Russian opponents. The 100 mm
plus armor on the KV-1 and the heavily angled 50 mm of the T-34
were both strongly resistant to German fire. The Panzerkommission
which was dispatched to examine this problem resulted in the
specifications for the Panzer V Panther; it also recommended new
suspension, increased armor and a more pwerful main gun for the
struggling Panzer IIIs and IVs. The interruption to supply that
such changes would cause meant the immediate change would be only
the Panzer IV's gun. In November, 1941 a 75 mm gun to match the
performance of the Rheinmetall Pak 44 L/46 (80 mm penetrated at
1,000 m with a standard 6.8 kg round) was demanded for the Panzer
IV from Krupp - with the first models to be in production by March
1942.
The rifled barrel was identical to the Rheinmetall
gun at 2470 mm, but it needed both a shorter recoil and shorter
rounds in order to fit in the Panzer IV turret and be operable. A
larger, but shorter, loading chamber and fatter rounds produced
the KwK 44 L/43. To further retard the recoil a distinctive
two-port muzzle brake was also standard. The first production guns
were finished in late March, although just eighteen examples were
made in that month.
The up-gunned Panzer IV were officially designated
as the Ausf F Umbau, in June 1942. The type was renamed the Ausf G
although there were initially no major differences between the F
and G tanks. There is some historical confusion between the F, F1
and F2 variants. From May 1942 the tank armor on all Panzer IV
variants was boosted with the addition of 30 mm of additional
front plate. The KwK 44 L/43 armed tanks did not have an
especially long production life, in April 1943 an longer and more
powerful gun was fitted to new models, the 75 mm KwK 40 L/48.
Early model Panzer IV tanks were often upgraded for increased
combat efficiency. From 1943, for example, surviving Panzer IV
models E/F were given additional armor and the 75 L/48 gun.
The aforementioned upgrades allowed the Panzer IV
to keep pace with newer designs such as the Sherman and the T-34.
Production continued and was stepped up even while the more
effective Panther medium tank was in service, because of the
Panzer IV's low cost and greater reliability; since the design was
already in use and tested in the battlefield they could be
upgraded and problems removed, while the Panther was a relatively
new model.
Small numbers of Panzer IV were supplied by
Germany to its allies. Hungary received ten and Romania eleven in
September 1942. Italy twelve and Turkey fifteen in May 1943. Spain
was gifted twenty in November 1943. From February 1943 to August
1944 Bulgaria received a total of 91 vehicles, enough to equip an
entire battalion, and used them against Germans in late 1944.
Romania was given a further 127 Panzer IVs in the same period as
the supplies to Bulgaria. In the final months of 1944 another 52
were sent to Hungary.
Finland bought 22 Panzer IV Ausf Js, of which 15
arrived, all too late to fight against the Soviets the
Continuation War (1941-44) or against German troops in the
following Lapland War (1944-45) and served as training vehicles
until 1962.
In 1950s/1960s Syria bought several dozens of
Panzer IVs from the USSR, France, Czechoslovakia and Spain and
employed them in the 1965 conflict over Jordan headwaters (often
referred to as Water War) and in the Six Days War (1967).
