THE PANZER III

Germany’s Medium Tank

The Panzer III was the common name of a medium tank that was developed in the 1930s by Germany and was used extensively in World War II. The official German designation was Panzerkampfwagen III Sd Kfz. 141 (abbreviated to PzKpfw III) translating as “armored fighting vehicle number three”.

The Panzer III was purpose designed to create a breakthrough on the battlefield and also to fight other armored fighting vehicles. The performance of the Panzer III was adequate in the early years of the war; however as the Germans came to face faced the formidable T-34 and KV-1 in Russia, it was immediately obvious that a stronger main gun with a considerably enhanced anti-tank capability was now needed. The Panzer IV had a bigger turret ring and was capable of mounting a larger main weapon, the traditional roles were therefore reversed. The Panzer IV mounted the long barreled 7.5 cm KwK 40 gun was detailed to fight in tank-to-tank battles, the Panzer III became obsolete in this role and for most purposes was supplanted by the Panzer IV. From 1942, the last version of Panzer III, Ausf. N, mounted the 7.5 cm KwK 37 L/24 short barelled howitzer better suited for infantry support. Production of the Panzer III ended in 1943. However, the Panzer III’s capable chassis provided hulls for the Sturmgeschütz III until the end of the war.

The constantly changing role of the Mark III required close scrutiny from Allied intelligence services in order to keep the front line troops up to speed on the variants which they faced in the field.

This wartime military intelligence report on the German Panzer III was originally published in the US intelligence magazine Tactical and Technical Trends, No. 10, October 22nd, 1942.

A good study of the Panzer III Ausf.E. Note the two machine guns in the turret.

MARK III TANK - THREE BASIC DESIGNS

Tactical and Technical Trends, No. 10, October 22nd, 1942.

Close examination of a considerable number of photographs of Mark III tanks, together with those available for examination in the Western Desert, indicates that the Mark III fighting-type tank is found in three basic designs.

Of these, the first has an armor basis of 30 mm (1.18 in) all around. The front sprocket has eight spokes, and the rear idler, though having eight spokes, is almost solid. This type is known originally to have been produced mounting a 37-mm gun and either one or two machine guns coaxially in the turret, with one machine gun firing forward in the hull. Later, however, the 50-mm was substituted for the original principal armament, and this mounting has only one machine gun mounted coaxially in the turret, the hull machine gun being retained. Of the actual specimens examined, all mounted the 50-mm gun (many are now mounting the long-barrelled type), and in these there has invariably been a Variorex gearbox, the steering being hydraulically operated. This basic type, irrespective of armament, has not been found to carry any additional armor, improvised or otherwise.

The second type has an armor basis of 30 mm all around with additional 30-mm plates bolted on. This type has a six-spoke front sprocket, and the rear idler, although having eight spokes, is more open than the first type. An ordinary six-speed gear box and hydraulically operated steering gear are fitted. Neither photographs nor specimens of this type have shown any principal armament other than the 50-mm gun with one coaxial machine gun. Moreover, every individual tank of this type has had similar additional 30-mm plates on the front and rear, this additional armor not having been found on any other type of Mark III fighting tank. The inference is, therefore, that this additional armor is actually part of the design of the tank and probably incorporated during manufacture. There have been no indications that this type originally mounted a 37-mm gun, although this remains a possibility.

The third type has 50-mm armor on the front and rear, with 30-mm armor on the sides. No additional armor has been found on any tanks of this type, and the armament has always been found to be the 50-mm gun with a coaxial machine gun and one machine gun in the hull. The front sprocket and rear idler are similar to those in the second type, and an ordinary six-speed gear box is fitted, the steering being operated by mechanical linkage. The driver’s and hull gunner’s entrance doors have been changed from the former double doors to single doors hinged at the forward edge. In place of the normal mantlet protecting the hull machine gun, a more hemispherical mantlet is fitted.

The following minor differences of design between these three basic types have also been noted. Originally on the first type the armor protecting the driver’s visor consisted of two plates, one being raised, and the other lowered, to give protection. The third type, and probably the second type as well, have had a single hinged piece of armor which can be lowered to give protection. The third type has also had a slightly different design of the two shields protecting the exhausts from the steering tracks. In the first and second types the air filters were located between the rear bulkhead of the fighting compartment and the engine, air being drawn from the fighting compartment. These filters were believed to be an oil-soaked gauze type. On the third type this arrangement superseded by four oil bath filters, installed over the top of the engine blocks.

The suspension on all these types has been the same, the familiar six small bogie wheels with three return rollers, a front sprocket, and a rear idler. Two early types, however, are known to have had respectively five large bogie wheels and eight small bogie wheels. Both these types mounted a 37-mm gun. Nothing has been heard of either type over a considerable period, and it is probable that they were prototypes only and not produced in significant numbers.

It is known that Mark III fighting tanks have been produced in at least five models designated ‘E’, ‘F’, ‘G , ‘H’, and ‘J.’ These models have consecutive chassis number blocks, and it is logical to assume that they are successive developments. There should therefore be a link with the development shown above, but so far it is not possible definitely to say what each model designation represents. It is, however, known that the first type described above has included Model ‘G’ tanks, and the third type has included Model ‘J’ tanks. All three types are known to have been in existence early in 1941, the third type probably being at that time a very new production.

It should be specially noted that, in describing German armor thickness, round numbers are almost invariably given. Careful measurement, has shown that these figures are frequently incorrect. 30-mm, for example, should almost invariably be up to 32-mm.

* * *

The vulnerability of German Tanks was an obvious area for investigation by intelligence gathering services. This article, also taken from Tactical and Technical Trends, provides an interesting contemporary intelligence report on vulnerability of German tanks to short-range attacks with incendiary grenades. It was originally published in Tactical and Technical Trends, No. 11, November 5th, 1942.

A Pz.Kpfw.III Ausf.G captured by the British in North Africa, 1942.

VULNERABILITY OF GERMAN TANKS

Tactical and Technical Trends, No. 11, November 5th, 1942.

When enemy armored force vehicles are attacked at close quarters with incendiary grenades, the air louvres are very vulnerable. It is therefore important that differentiation be made between “inlet” and “outlet “ducts, since obviously a grenade thrown against an exhaust opening will be less effective than one aimed at an inlet, which will draw the inflammable liquid into the vehicle. If the engine is not running, all openings are equally vulnerable.

In general, it may be said that in the Pz Kw II and III tanks the best targets are the flat top-plates of the rear superstructures, since the air intakes are located there. The side louvres in these tanks are invariably protected by a vertical baffle. On the Pz Kw IV, the left side ports are intake and thus more vulnerable than the right-hand exhaust ports.

* * *

The following report on the new armament of the up-gunned German Pz.Kw. III originally appeared in Tactical and Technical Trends, No. 20, on 11th March 1943. This is how Allied troops were informed of the fact that the Panzer III was now operating in a more efficient form. American reports from the period invariably refer to the German tanks using Arabic rather than Roman numerals.

NEW ARMAMENT OF GERMAN PZ.KW. 3

Tactical and Technical Trends, No. 20, 11th March 1943

As previously reported in Tactical and Technical Trends (No. 4, p. 15) recent models of two German tanks, the Pz.Kw. 3 and 4, have been fitted with more powerful armament, as shown in the accompanying sketches. These sketches are based on photographs of German tanks captured by the British in North Africa.

Pz.Kw. 3

The principal armament of this tank is a long-barrelled 50-mm gun. It is reported that this gun bears considerable similarity to the 5-cm Pak 38 (50-mm antitank gun), except that there is no muzzle brake and that the mounting is, of course, different. The over-all length from the breech opening to the muzzle is 9 feet, 4 inches. The barrel overhangs the front of the tank by about 3 feet. The ammunition used is that of the 50-mm antitank gun with no adaptation or alteration apart from the fitting of an electric primer, the tank gun being electrically fired. The muzzle velocity of this tank gun has been estimated as a little over 3,000 feet per second. It has been reported that the performance of the tank gun should not be very different from that of the antitank gun, the estimated penetration figures for which are as follows:

· 79-mm (3.1 in) homogeneous armor at 300 yds at 30°

· 71-mm (2.8 in) homogeneous armor at 600 yds at 30°

· 63-mm (2.5 in) homogeneous armor at 850 yds at 30°

* * *

Advice on how to combat the Panzer III was required and the following article, from Tactical and Technical Trends, No. 22, April 8th, 1943, describes areas on German tanks vulnerable to attack with incendiary grenades or Molotov cocktails.

VULNERABLE SPOTS FOR INCENDIARY GRENADES ON GERMAN TANKS

In attacking enemy tanks at close quarters with Molotov cocktails or incendiaries, the air intakes are among the most vulnerable points. It is important, therefore, that the location of these intakes and outlets be known, as the flame and fumes of a grenade thrown against an intake while the engine is running will be sucked inside, but if the grenade lands on an outlet, they will be blown clear of the tank.

The best targets are the flat top-plates behind the turret. Side intakes are invariably protected by a vertical baffle. The accompanying sketches show the “soft spots” on German tanks Pz.Kw.3

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The response to these and other threats was to increase protection on the Panzer III. This U.S. intelligence report on the Panzer III and its increasing armor specification originally appeared in Tactical and Technical Trends, No. 25, May 20th, 1943.

INCREASED PROTECTION ON PZKW 3

Tactical and Technical Trends, No. 25, May 20th, 1943.

The history of the changes in the light medium PzKw 3 demonstrates how fortunate the Germans were in having a basic tank design that could be improved as battle experience indicated, for a basic design can be improved and still remain familiar to the users. Furthermore, the problems of maintenance and supply of parts are greatly reduced and these problems are a major factor in keeping tanks ready for operational use.

(1) General

The Germans seem to be making a gradual increase in thickness of armor-plate as the guns used against it increase in hitting power and range. The PzKw 3 medium tank is illustrative of this trend in tank armor and design, and affords a remarkable example of what can be done to improve the armor protection and fighting efficiency of a tank without changing its basic design. The key of this basic design is the welded main structure which allows heavier plates to be used when desired. Also, operating components of the tank are not hung on the plates, likely to be changed to thicker ones.

A Panzer III packed with fifteen or more grenadiers conveys the impression of just how sturdy these machines were.

(2) Pre-War

The early model PzKw 3 (produced in 1936-38) had basic armor of .59-inch homogeneous plate. At this time there were only 5 bogie wheels on a side instead of the present 6. There is a gap in the formation until 1939, when the tank appeared with 1.18-inch face-hardened armor on the turret and front. This model had 6 bogie wheels on the side. The side armor which forms a great part of the chassis was of softer, machineable-quality plate, due both to necessities of manufacture and to the undesirable weakening effect on hardened plate of the necessary suspension and bracket holes. The model also had improved aperture protection in the form of an external moving mantlet, additional armor around the machine-gun port, and an improved double-flap driver’s visor. It appears that these features were added with the modification of but 2 plates on the tank.

(3) 1941 Changes

In 1941, as more powerful guns were being used against tanks, 1.20 inches of additional armor plate was bolted against the plates on the front of the superstructure and on the upper and lower nose-plates. The 1.18-in. basic plates were face-hardened to a Brinell hardness of 600 to 800 and 1.20-in additional plates were the same. About a year later, in January 1942, the tank appeared with a basic armor of 1.96 inches on the front and back, the side-armor thickness remaining unchanged at 1.20 inches. This armor was face-hardened and performed well against monobloc shot, but once the face-hardening was pierced, the shell fragments penetrated the remainder with ease.

(4) 1942

Therefore, in June 1942, a .79-inch additional plate was bolted on the gun mantlet and front superstructure as a means to defeat a shot with a piercing cap. Between this plate and the basic armor was an air gap or space, varying from 4 to 8 inches. The plate conformed roughly to the shape of the section covered. The spaced armor seems to have been a field expedient, resulting undoubtedly from the demonstrated fact that the spare section of track carried on the front of German tanks gave additional protection. This method of adding armor was officially recognized, as later models had brackets fitted for installing spaced armor when desirable.

* * *

Four photographs of German Panzer III tanks captured in North Africa were exhibited in Tactical and Technical Trends, No. 32, August 26th, 1943.

GERMAN PzKw 3

Tactical and Technical Trends, No. 32, August 26th, 1943

The accompanying photographs show four views of the German medium tank PzKw 3. Figures 2, 3 and 4 is the PzKw 3 with the long-barreled 50-mm gun. Figure 1 is essentially the same tank except that it is equipped with a short-barreled 50-mm gun.

***

The intelligence report on the German Panzer III Flammpanzer, entitled “German Flame Thrower on Pz Kw 3 Chassis” was originally published in Tactical and Technical Trends, No. 45, April 1st, 1944. As we have seen some 100 Panzer III were converted to perform this role. The initial report contained some errors and a later report in the July 1944 issue corrected some of the details given in this article.

GERMAN FLAME THROWER ON PZ KW 3 CHASSIS

Tactical and Technical Trends, No. 45, April 1st, 1944

a. THE TANK

German flame-throwing tanks were noted in Tactical and Technical Trends, No. 19, p. 9, and in No. 39, p. 9, a Pz Kw 2 tank was described, mounted with two small flame throwers on the front end of the track guards. At that time, it seemed odd that a more powerful projector should not be installed in the turret. Such a tank has now appeared. Flame-thrower Pz Kw 3 tanks were taken on the Italian front, some in good condition. A front view of this tank is shown in figure 1.

Fig.1: Flame-thrower tank

(1) External Appearance

The flame-throwing tank has a special type of flame thrower mounted on some available chassis. Reports indicate that flame-throwing apparatus is designed to be adaptable to any model of tanks, light as well as heavy. The tank here described is a standard Pz Kw 3 with six bogies and three return rollers. The chassis, hull and turret are identical with the ordinary tank. An additional armor plate 1.18 inch thick has been welded to the front of the chassis and another of like thickness forms the curved shield protecting the front of the turret and the flame gun. This shield is pierced for one coaxially mounted machine gun, and another is mounted in the usual position in the right front of the hull, opposite the driver’s vision slit. Smoke projectors of three tubes each are mounted on each side of the front edge of the turret. For comparison see figures 2 and 3. The markings are the standard black-and-white German crosses on the right rear of the chassis, and a little in front of the center roller. Organizational numbers appear on the two sides of the turret directly above the black-and-white cross. Two tanks captured in good condition were marked respectively, F. 23 and F. 24.

(2) Flame Gun

At first sight, the flame gun which projects 5.28 feet beyond the curved shield of the turret, has the identical appearance of the usual 50-mm tank cannon. Even the short reinforcing jacket is simulated. However, the barrel has no taper whatever, and if seen from the muzzle end, is thin-walled, like a shotgun barrel. This “gun” is actually the cover for the flame-projector tube. The muzzle end of the gun is detachable, forming a flame shield designed to facilitate the burning of the flame-oil by having four openings cut in the sides, .4 inch wide and 4.9 inches long, see figure 4. The top and side openings are shielded to prevent the dropping of unburned flame oil on the top of the tank.

Within the turret, a counter-balance weight is attached to the breech of the gun for ease in vertical alignment. Elevation and traverse are controlled by the tank commander through two hand wheels — the right controlling elevation, the left the swing of the turret. The maximum elevation of the flame gun is about 530 mils (30 degrees); the depression, 180 mils (10 degrees). The indicated horizontal traverse is approximately 800 mils (44 degrees) right and left of center. An indicator with a dial numbered clockwise from 1 to 12 to indicate the position of the turret with reference to the forward motion of the tank is placed near the hand wheels.

Comment: The turret does NOT have an all-round traverse and no machine gun fires rearward. This flame-thrower tank therefore appears to be more vulnerable to attacks of tank-destroyer squads than the gun-carrying model.

(3) Mechanical Operation

Pressure for the flame-thrower fluid is obtained by the operation of an auxiliary two-cylinder motor driving a rotary pump located in the left rear of the tank. Flame-oil pressure is indicated by a pressure gage directly in front of the tank commander, graduated from 0 to 250 units. The flame-oil release is obtained by the dual operation of a right-foot pedal and an electric control mounted above and behind the pressure gage. At the muzzle of the flame gun are two pilot jets; two electric, ground-return igniters, and one opening .394 inch in diameter for the ejection of the flame fluid.

(4) Sighting

Aiming is accomplished by the tank commander sighting through an improvised rear sight, two mm (.08 inch) square and mounted in the turret directly in the rear of the shatter-proof-glass vision slit, and aligning the target with an improvised front sighting device mounted on top of the exterior base of the flame gun (see figure 5). The elevation for estimated target range is obtained by elevating the flame gun so that the line of sight passes over the selected one of three metal horizontal projections, attached to the vertical bar of the front sight. Elevated to range, the gun is kept trained on the target as the tank approaches. As the sights are aligned, the commander presses the electric control and the right-foot pedal. In short bursts the flaming oil is sprayed upon the target, the liquid sticking and burning with intense heat upon the object it touches. The range is normally from 55 to 65 yards; maximum, 84.

(5) Fuel Tanks and Flame Oil

The flame-oil fuel tanks consist of two welded metal containers of approximately 40 to 50 gallons each, mounted beside the tank commander on the right and left of the chassis, set low enough to allow free rotation of the turret, and fitted with meter gages.

The fuel is a thin, black, sticky oil smelling strongly of creosote, which showed upon analysis the following composition by volume:

· Light oils up to 170° - 39.0 percent

· Medium or carbolic oils from 170 to 230° -17.4 percent

· Heavy oils or creosote from 230 to 270° - 4.2 percent

· Medium oils or (coal tar?) oils, 270° - 21.5 percent

· Residual difference at 100 - 17.9 percent

(6) Accessories

(a) Smoke Projectors

Two three-barreled smoke projectors are bolted to the forward sides of the turret and with the center barrel approximately aligned with it, all having an elevation of about 44 degrees. The two outer barrels fire laterally right and left from the center barrel at approximately 20 degrees. These are fired electrically from a lid-covered firing box on the inside of the turret. Each button of the box set is connected with one barrel of the projector. The projectile used is the standard smokepot weighing about five or six pounds, which can be projected an estimated distance of from 150 to 200 yards. The pot produces an opaque, light-gray cloud for about two minutes.

(b) Radio

A pair of radio head sets for intertank or interior communication are supplied to the driver and commander for listening, and connected parallel with the radio operator for inner-phone communication.

(c) Demolition Charge

For the destruction of the tank in case of imminent capture, a demolition charge is provided. The one examined weighed about 8.5 pounds, and was 15 inches long, 3.54 inches in diameter, containing a dense, white solid — perhaps nitro-starch. A fuze screwed into a booster, and a soft, gray-iron hanging strap for fastening the charge to an object were attached. The charge fitted snugly into a metal carrying case.

(d) Very Pistol

A Very pistol was carried on the right side of the turret behind the commander’s right shoulder, with two boxes of 12 colored flares each, one in the rear of the commander’s seat, the other beside the turret machine gun. Red, blue or violet, green and white cartridges were provided. Their signal meaning is changed by order of the commanding officer, but it is believed the following apply:

· Red -  Enemy attacking

· Blue or violet - Attack by tanks

· Green - Help

· White - We are here

· Flares fired into the enemy’s lines - We are withdrawing

(e) Miscellaneous Accessories

Spare multi-layer vision-slit glasses for the commander and driver, totalling 3.34 inches in thickness, were stored in racks. There were also three fire extinguishers, standard gas masks for the crew, and a spare smokepot. In one tank a rack of black egg-grenades 3 inches long by 2 inches in diameter were found. Racks for four fire extinguishers were provided on Pz Kw 3 flame-throwing tanks, two for the tank commander, one for the tank driver and one mounted on the outside of the tank.

(7) Crew

The crew apparently consists of four — commander, driver, radio operator, and turret machine gunner.

b. TACTICAL USE

(1) Tank Attack

Two Pz Kw 4’s and a Pz Kw 3 flame thrower attacked a platoon position unsupported by AT guns in the following manner: the two Pz Kw 4’s opened fire at 400 yards with machine guns from a hull-down position. Still firing, they advanced to about 200 yards where they remained, continuously firing their machine guns.

At the same time, the flame thrower advanced between the two, actually reached the platoon in spite of machine- and Bren-gun fire, and sprayed the men at close range.

Other data indicates that the flame-throwers are usually attached to units of Pz Kw 4 tanks in the ratio of two or three flame throwers to 20 or 25 standard tanks. Their greatest value comes into play when darkness, smoke, or weather conditions make possible a close approach. Against woods, trenches, blockhouses or buildings, flame thrower tanks force defenders into the open where they can be attacked with small-arms fire. Buildings up to four stories in height can be successfully attacked. The Pz Kw 3 was extensively employed at the siege of Stalingrad.

(2) Target Area

The most vulnerable target areas are the vision slits of the tank commander and driver, the area of the center roller on the side, and the right side of the rear end of the chassis. This is also the best target for Molotov cocktails.

A Flammpanzer III demonstrates the effectiveness of it main armament.

Development History

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 kilometres per hour (21.75 mph). It was intended as the main tank of the German Panzer divisions, capable of engaging and destroying opposing tank forces.

Daimler-Benz, Krupp, MAN, and Rheinmetall all produced prototypes. Testing of the prototypes took place in 1936 and 1937, leading to the Daimler-Benz design being chosen for production. The first model of the Panzer III, the Ausf. A, came off the assembly line in May 1937, and a total of ten, two of which were unarmed, were produced in 1937. Mass production of the Ausf. F version began in 1939.

Between 1937 and 1940, attempts were made to standardize parts between Krupp’s Panzer IV and Daimler-Benz’s Panzer III.

Much of the early development work on the Panzer III was a quest for a suitable suspension. Several varieties of leaf-spring suspensions were tried on Ausf. A through Ausf. D before the torsion-bar suspension of the Ausf. E was standardized. The Panzer III, along with the Soviet KV heavy tank, was one of the first tanks to use this suspension design.

A distinct feature of Panzer III, influenced by British Vickers tanks, was a three-man turret. This meant that commander was not distracted with either loader’s or gunner’s tasks and could fully concentrate on maintaining situational awareness. Other tanks of the time did not have this capability, providing the Panzer III with a potential combat advantage. For example the French Somua S-35, had only one-man turret crew, and the Soviet T-34 (originally) had two-men. The practical importance of this feature is signified by the fact that not only all the further German tank designs inherited it, but also later into the war, most of the Allied tanks’ designs either quickly switched to the three-man turret, or were abandoned as obsolete.

The Panzer III, as opposed to Panzer IV, had no turret basket, merely a foot rest platform for the gunner.

An early 1941 image of the North Africa campaign - the crew are wearing the original tropical issue pith helmets.

The Panzer III was intended as the primary battle tank of the German forces. However, when it initially met the KV and T-34 tanks it proved to be inferior in both armor and gun power. To meet the growing need to counter these tanks, the Panzer III was up-gunned with a longer, more powerful 50-mm (1.97 in) cannon and received more armor although this failed to effectively address the problem caused by the KV tank designs. As a result, production of self-propelled guns, as well as the up-gunning of the Panzer IV was initiated.

In 1942, the final version of the Panzer III, the Ausf. N, was created with a 75-mm (2.95 in) KwK 37 L/24 cannon, a low-velocity gun designed for anti-infantry and close-support work. For defensive purposes, the Ausf. N was equipped with rounds of hollow charge ammunition which could penetrate 70 to 100 mms (2.76 to 3.94 in) of armor depending on the round’s variant but these were strictly used for self-defense.

The emergence of the Panzer III with 75-mm Gun signalled the fact that the Panzer IV had finally usurped the role of main battle tank relegating the Panzer III to its former role as an infantry support tank. By 1943 with Germany on the defensive there was always the possibility that the Panzer III would meet other tanks with better armor and a far better main armament. The Panzer III Ausf.N was not a success on the battlefield, technology had moved on and production ended early in 1943.

The following intelligence report on the German Panzer III Ausf. N armed with the short 75-mm gun was published in Tactical and Technical Trends, No. 21, March 25, 1943.

PZ. KW. 3 WITH 75-MM GUN

Tactical and Technical Trends, No. 21, March 25, 1943

Among enemy tanks recently examined in the Middle East was a Pz. Kw. 3 mounting a short-barreled 75-mm gun (7.5-cm KwK 38), identical with the short-barreled gun mounted on the Pz. Kw. 4. [Recently Pz. Kw. 4’s with a long-barreled 75-mm gun have been encountered by Allied forces (see Tactical and Technical Trends, No. 20, p. 10).] The tank had been demolished, but it appeared that the only alteration, apart from the substitution of the 75-mm gun for the normal 50-mm gun, was the fitting of the armored barrel-sleeve into the front plate of the recoil mechanism belonging to the 75-mm. (Compare accompanying sketch with sketch of Pz. Kw. 3 armed with the long-barreled 50-mm gun, appearing in Tactical and Technical Trends, No. 20, p. 11.)

The German nomenclature for this tank is not known, but recently the Germans have referred to an Einheitspanzer. This is said to be a new standard tank combining the best features of both Pz. Kw. 3 and 4, and to consist of a Pz. Kw. 3 chassis with a short-barreled 75-mm gun mounted in the turret. If this is true, the tank examined may be an Einheitspanzer.

Another Pz. Kw. 3 with the short-barreled 75-mm gun has been captured in Tunisia. Presumably this is the same model tank as that examined in the Middle East.

***

THE EVOLUTION ON THE PANZER III

Trials and tests of new prototypes took place from 1936 to 1937 on testing grounds in Kummersdorf and Ulm. They resulted in the Daimler-Benz design being chosen for full-scale production and in early 1937, Waffenamt ordered Daimler-Benz to produce the first series (0-Series) of their design.

Krupp’s ZW prototype, designated as MKA, featured leafsprings and bogie wheel mountings type of a suspension. In turn, many features of this vehicle were used in the design of Panzerkampfwagen IV, which was designed by Krupp.

The PzKpfw III design was composed of four sections - hull, turret, and front superstructure with the opening for the turret and rear superstructure with the engine deck. Each section was of a welded construction and all four were bolted together. The hull was divided into two main compartments divided by a bulkhead. The front compartment housed the gearbox and steering mechanism, and the rear one both the fighting and engine compartment. Basic hull, turret, superstructure and crew layout remained unchanged throughout the production life of Panzerkampfwagen III series.

After modifications, the first Panzerkampfwagen III Ausf A (1-Serie) was produced in May of 1937 by Daimler-Benz, with total of 10 produced until the end of 1937 (chassis numbers 60101-60110). Some sources state that as many as 15 were manufactured. Only eight Ausf As were armed (and equipped units of 1st, 2nd and 3rd Panzer Division and took part in the Anschluss, the take-over of Sudetenland and the Polish Campaign) and other unarmed Ausf As were used for further testing.

In 1937, the Ausf B (2-Serie) was produced by Daimler-Benz with total of 15 produced (chassis numbers 60201-60215). A number of Ausf Bs saw service during the Polish Campaign. In October of 1940, five Ausf B tanks were modified and used as prototypes of Sturmgeschutz III series.

A Panzer III advances along a railway line during the early stages of Operation Barbarossa, July 1941.

In June of 1937, the next variant Ausf C (3a-Serie) was produced by Daimler-Benz and its production ended in January of 1938, again with total of 15 produced (chassis numbers 60301-60315). A number of Ausf Cs saw service during the Polish Campaign.

In January of 1938, the next variant Ausf D (3b-Serie) was produced by Daimler-Benz and its production ended in 1939 with total of 55 produced (chassis numbers 60221-60225 and 60316-60340). Only 30 Ausf Ds produced in two groups of 15 were armed, and another 25 unarmed Ausf Ds were used for further testing. A number of Ausf Ds saw service during the Polish Campaign and in Norway.

The early models of Panzer III (Ausf A, B, C and D) were pre-prototypes of the entire series produced exclusively by Daimler-Benz. All were unsuitable for large-scale production but each new model was considered an improved version of the previous one. Each model featured different type of suspension e.g. Ausf A - individual coil springs, Ausf B - two sets of leaf springs, Ausf C - three sets of leaf springs and Ausf D - angled leaf springs.

Ausf A, B, C and D were powered by 250hp petrol Maybach HL 108 TR engines with a 5 or 6 speed Zahnradfabrik gearbox. All early models were armed with 37mm KwK 35/36 L/46.5 gun and three 7.92mm MG 34 machine guns (two mounted co-axially beside the main armament in the turret and one in the hull). Their armor protection ranged from 5 to 15mm, offering protection only against anti-tank rifles and machine gun fire. The reason behind the inadequate armor protection was a result of Daimler-Benz keeping the vehicle in its designated weight range of 15 tons. Some of early models were up-armored and had their maximum armor protection increased to 30mm. Ausf A, B, C had simple drum shaped “dustbin” commander’s cupolas, while Ausf D had cast cupolas similar to that of the PzKpfw IV Ausf B.

A few of the early Panzer IIIs saw actual combat (with units of 1st, 2nd and 3rd Panzer Division) during the Polish Campaign, others were troop tested (1937-February 1940). In February of 1940, existing number of early Panzer IIIs was handed over to NSKK for training purposes. Afterwards, only a few Ausf D saw service with PzAbt zbV 40 (along with PzKpfw NbFz VI) during fighting in Norway in April/May of 1940, followed by service with PzAbt zbV 40 in Finland, 1941/42.

Raw Materials Used in Production of PzKpfw III:

· Steel: 39000.00kg

· Tin: 1.40kg

· Copper: 60.10kg

· Aluminium: 90.40kg

· Lead: 71.10kg

· Zinc: 49.10kg

· Rubber: 125.00kg

In December of 1938, the Ausf E (4-serie) entered production, and 96 were produced by Daimler-Benz, Henschel and MAN when production ended in October of 1939 (chassis numbers 60401-60496). It was the first PzKpfw III that was produced in any significant number. The basic design remained unchanged from its predecessor, but it featured a new independent torsion bar suspension, designed by Ferdinand Porsche for the automotive industry in 1930s. It was composed of six roadwheels and three return rollers. The Ausf E was armed with a 37mm KwK 35/36 L/46.5 gun and three 7.92mm MG 34 machine guns (two in the turret and one in the hull). Its armor protection ranged from 12 to 30mm. During production, escape hatches were installed on both sides of the hull and a vision port was added on the superstructure side for the radio-operator. The driver’s visor was provided with an upper and lower sliding shutter, which could be closed together. Also two-piece side hatches were installed in the turret. Unlike its predecessors, the Ausf E was powered by new 300hp petrol Maybach HL120TR engine with a new Maybach Variorex 10 speed gearbox. It was also heavier than all previous models, which were in the 16 ton range but Ausf E weighted 19.5 tons. From August 1940 until 1942, all Ausf E tanks were rearmed with a 50mm KwK 38 L/42 gun mounted in an external mantlet also housing one MG. At the same time, armor protection was increased by the installation of 30mm armor plates to the hull, front and rear, as well as the superstructure front. During service, the number of Ausf E tanks was also reworked to Ausf F standard.

In September 1939, another new variant, the Ausf F (5-serie) entered production. Until July 1940, 435 were produced by Daimler-Benz, Henschel, MAN, Alkett and FAMO (chassis numbers 61001-61650). It was a refined version of the Ausf E and it did not feature any significant modifications or changes other than an improved Maybach HL120TRM engine and modified upper hull nose (with air intakes). The first 335 Ausf F tanks were armed with a 37mm KwK 35/36 L/46.5 gun and three 7.92mm MG 34 machine guns (two in the turret and one in the hull). The last 100 tanks were factory armed with a 50mm KwK 38 L/42 gun mounted in an external mantlet housing one MG. Ausf F vehicles were fitted with a hull rear mounted rack of five smoke generators remotely released from the turret. Some vehicles were also mounted with a stowage box at the rear of the turret. From August 1940 until 1942, all 37mm Ausf F, just as Ausf E tanks, were rearmed with 50mm KwK 38 L/42 guns. They also had their armor protection improved at the same time as Ausf E tanks. Only 40 Ausf F tanks with 50mm KwK 38 L/42 guns were rushed into service before the end of the French Campaign and saw little or no combat. There is still controversy surrounding this as it is reported that the first PzKpfw III armed with 50mm guns entered production in July of 1940. The first production of Sturmgeschutz III assault guns / tank destroyers were based on the Panzerkampfwagen III Ausf F chassis and components. In 1942/43, a number of Ausf F tanks were rearmed with a 50mm KwK 39 L/60 gun. Rearmed and up-armored Ausf F tanks remained in service as late as June of 1944 (e.g. 116th Panzer Division in Normandy).

An interesting fact is that the study report of the captured PzKpfw III Ausf F made by the British in 1942, was then sent to United States Army Ordnance Department where it was decided to utilize a copy of German torsion bar suspension system in future American tanks (e.g. M18 Gun Motor Carriage, M24 Chaffee, M26 Pershing etc.).

In 1940/41, attempts were made to standardize the production of Panzer III and Panzer IV. A few prototypes based on the Panzer III Ausf G/H with new large overlapping roadwheels and FAMO suspension were produced - PzKpfw III Ausf G/H mit Schachtellaufwerk. Since 1940, prototypes were used for testing and training purposes. Further development was halted and in 1943/44, prototypes were fitted with dozers and were used to clean up the streets of bombed cities. This suspension was later adopted in Tiger and Panther.

A Panzer III Ausf L with schurzen in Russia, 1943.

From April 1940 to February 1941, 600 new Ausf G (6-serie) tanks were produced by Daimler-Benz, Henschel, MAN, Alkett, Wegmann, MNH and FAMO (chassis numbers 65001-65950). The Ausf G was a slight improvement over previous Ausf E and Ausf F tanks. Some 50 Ausf G tanks were armed with 37mm KwK 35/36 L/46.5 guns mounted in an internal mantlet, while the rest were armed with a 50mm KwK 38 L/42 gun mounted in an external mantlet. Both 37mm and 50mm tanks had additional two MG 34 machine guns, one in the turret and another in the hull. Armor protection ranged from 12mm to 30mm, although the majority of the protection ranged from 21mm to 30mm. Also a new pivoting visor for the driver (Fahrersehklappe 30) was installed. The turret was modified and mounted on the roof with a fan exhaust and one signal port was eliminated. Mid-production vehicles were mounted with the new type of commander’s cupola as used in the PzKpfw IV Ausf E, F and G, which became standard on all later models of PzKpfw III. Late production vehicles had wider 400mm tracks instead of standard 360mm tracks. The Ausf G was the first to be mounted with the “Rommelkiste” (Rommelbox) - turret mounted storage bin (Gepack Kasten), which then became the standard on all PzKpfw IIIs. From August 1940 until 1942, all 37mm Ausf G tanks just as Ausf E and F tanks were rearmed with the 50mm KwK 38 L/42 gun. Vehicles sent to North Africa were equipped with additional air filters and a different cooling fan reduction ratio. They were designated Ausf G(Tp), Tp being short for Tropisch / Trop / Tropen - tropical. A small number of Ausf G tanks remained in service as late as September 1944.

In October 1940, the Ausf H (7-serie) entered production. It was produced by MAN, Alkett, Henschel, Wegmann, MNH and MIAG until April of 1941 with 308 produced (chassis numbers 66001-66650). The Ausf H featured a newly designed turret to mount a 50mm gun with a single 30mm armor rear plate. Armor protection ranged from 10mm to 30mm, but hull, front and rear, as well as the superstructure front had 30mm armor plates bolted on to them increasing the protection. The increase in armor protection in the Ausf H neutralized the threat of British 2pdr, Soviet 45mm and American 37mm anti-tank guns. The new six speed Maybach SSG 77 gearbox replaced the previously used Variorex. In addition, the suspension system was slightly modified and new sprocket and idler wheels were used in the Ausf H. Consequently, because of the weight gain to 21.8 tons, due to the increase in armor protection, torsion bars were strengthenedd. Originally, the Ausf H was armed with a 50mm KwK 38 L/42 gun and two MG 34 machine guns, but in 1942/43, they were rearmed with a50mm KwK 39 L/60 gun.

Ausf E, F, G and H were designated as Panzerkampfwagen III Ausf E, F, G and H / Sd.Kfz.141.

As of May 10th 1940, the Panzertruppe had only 381 Panzer III models in service, but 135 were lost during the Blitzkrieg in the west.

In March 1941, the last Sd.Kfz.141 and the first Sd.Kfz.141/1 Panzerkampfwagen III tank - Ausf J (8-serie) entered production. It was produced by Daimler-Benz, MAN, Alkett, Henschel, Wegmann, MNH and MIAG until July 1942 with 2616 produced (chassis numbers 68001-69100 and 72001-74100). The Ausf J had its armor protection significantly improved and it ranged from 10mm to 50mm. The increase in armor was accompanied by the installation of the new driver’s visor (Fahrersehklappe 50) and a ballmount (Kugelblende 50) for a 7.92mm MG 34 machine gun in the hull. A new type of front access hatch was installed along with new air intakes on the hull front. From April 1942, 20mm spaced armor was added to the gun mantlet and/or superstructure front. 1549 vehicles produced from March 1941 to July 1942 were armed with a 50mm KwK 38 L/42 gun and two MG 34 machine guns. Those vehicles were designated as PzKpfw III Ausf J / Sd.Kfz.141. 1067 vehicles produced from December 1941 to July 1942, were armed with 50mm KwK 39 L/60 and two MG 34 machine guns. Those vehicles were designated as PzKpfw III Ausf J / Sd.Kfz.141/1. The only difference between these models was the main armament and ammunition stowage for 84 rounds in contrast to the previous 99 rounds. When encountered in North Africa, the British nicknamed the 50mm L/60 Ausf J the “Mark III Special”. The 50mm L/60 gun was a significant improvement over the original 37mm gun, although it was still inadequate to deal with American M4 Sherman and Soviet T-34/76 tanks. In 1941/42, there was an unsuccessful attempt by Krupp to mount the Ausf J with Panzerkampfwagen IV Ausf G’s turret to create a new Panzerkampfwagen III variant designated Ausf K.

A Panzer III in action during the Demjansk pocket battle.

From August to November 1942, 81 Ausf J tanks were produced as command tanks - Panzerbefehlswagen III mit 5cm KwK L/42 / Sd.Kfz.141. From March to September 1943, an additional 104 Ausf J were converted as well. The vehicle was the basic Ausf J tank but it lacked a hull machine gun and carried less ammunition (75 rounds). It was fitted with additional radio equipment and periscope.

In June 1942, the Ausf L tank entered production. 653 were produced by Daimler-Benz, MAN, Alkett, Henschel, Wegmann, MNH and MIAG until December 1942 (chassis numbers 74101-75500). The Ausf L was armed with a 50mm KwK 39 L/60 gun and two 7.92mm MG 34 machine guns. Externally it was almost identical to the late model Ausf J as it was developed by modifying it. The main difference was the new torsion bar gun counter balance, which replaced the original coil spring gun recoil mechanism. Armor protection of the front turret was increased from 30mm to 57mm and 20mm spaced armor was installed on the superstructure front, and in many cases on the gun mantlet. The design of the vehicle was simplified as the rear deck was modified (air-intakes and hatches) and early in production the hull escape hatches, the loader’s vision port on the mantlet and turret side ports were removed. The Ausf L was also mounted with a new special system to transfer heated engine coolant from one vehicle to another. A single Ausf L was mounted with an experimental 75/55mm tapered-bore KwK0725 gun and was designated as PzKpfw III Ausf L mit Waffe 0725. Vehicles send to North Africa were equipped with additional air filters, modified oil filters, a different cooling fan reduction ratio and were designated as Ausf L(Tp). The Ausf L was also first to be mounted with an anti-aircraft machine gun mount (Fliegerbeschussgerat 41/42) on the commander’s cupola. This became standard on all new PzKpfw III tanks and was mounted on older models during service. Many were mounted with 5mm hull and turret armor skirts (Schurzen).

From October 1942 to February 1943, 250 new Ausf M (10-serie) tanks were produced by Wegmann, MIAG, MAN and MNH (chassis numbers 76101-77800). The Ausf M was a late production model Ausf L mounted with new wading equipment allowing wading up to depth of approximately 1.3m, in contrast to the previous 0.8-0.9m. This led to all air inlets and outlets as well as other openings and joints being sealed, while a modified muffler with closure-valve was installed high on the hull rear. The new system was developed and a modified version was used in Tauchpanzer III submersible wading tanks. The hull rear mounted rack of five smoke generators was replaced by three 90mm NbK dischargers mounted forward on both sides of the turret. The Ausf M just as the Ausf L was armed with a 50mm KwK 39 L/60 gun and two 7.92mm MG 34 machine guns. Vehicles produced in 1943 were factory mounted with 5mm hull and turret armor skirts (Schurzen). Large number of Ausf M were converted to either Sturmgeschütz III or Ausf N.

***

A report on mounting of 50-mm tank gun in German Panzer III tanks, from Tactical and Technical Trends, No. 33, September 9, 1943.

MOUNTING OF 50-MM KW.K 39 TANK GUN

Tactical and Technical Trends, No. 33, September 9, 1943

A preliminary examination in the United Kingdom of a captured PzKw 3 Model L (Tp)* has disclosed that the long-barreled 50-mm tank gun, 50-mm Kw. K 39, is balanced by means of a torsion-bar compensator.

As shown in the sketch overleaf, the torsion bar is mounted on the inside of the turret roof parallel to the trunnion axis and is anchored at each end. An arm is attached to the center of the bar which carries at its free end a pair of rollers. The bar is pre-set so that the rollers exert a downward force on a flat plate bolted to the gun cradle a few inches from the trunnion axis.

It will be seen from the sketch that, as this plate is fairly close to the trunnion axis, the maximum twist of the bar (from full depression to full elevation) is quite small.

The short tank gun, 50-mm Kw. K, in a captured PzKw 3 Model J previously examined was balanced by a coil spring in compression on the right of the mounting.

*The abbreviation Tp (Tropmunition) following the model-letter of the tank indicates that this tank is adapted for use in the tropics.

***

From February 1943 to April 1943, 100 Ausf M tanks produced by MIAG in Braunsweig (chassis numbers 77609-77708) were converted by Wegmann in Kassel to Flammpanzer - flame-thrower tanks. These new vehicles were designated as PzKpfw III (Fl) / Sd.Kfz 141/3. They were also commonly known as Flammpanzer III or Panzerflammwagen III. It was an unmodified Ausf M tank with an additional 30mm to 50mm armor plates welded on for protection to the hull front. This was done because Flammpanzer III tanks had to get closer to their targets and were more vulnerable to enemy fire. In contrast to regular tanks, it was operated by a three men crew composed of commander/flame gunner, radio operator/hull gunner and driver. The main gun and internal ammunition stowage were replaced with the flame-thrower and fuel tanks. This vehicle was armed with a 14mm Flammenwerfer flame-thrower and two 7.92mm MG 34 machine guns. The flame-thrower was mounted in place of the original 50mm gun and concealed in a thick 1.5m long pipe made to appear as standard armament. The flame-thrower could be lowered 8 degrees and raised 20 degrees. Each vehicle carried some 1020 liters of inflammable oil (Flammol) in two tanks inside the vehicle. Oil was pumped into the pipe by a Koebe pump driven by a two-stroke DKW engine, and was ignited by an electric charge (Smitskerzen). The supply of oil allowed some 125 one second or some 80 to 81 two to three seconds long bursts. The maximum range of the flame-thrower was 60m using ignited oil and 50m using cold oil. The range also depended on the weather conditions.

Panzerkampfwagen III Ausf E/F in Russian village.

The Flammpanzer III was designed in mind with fighting in the urban areas such as Stalingrad, but it was never to reach its destination. Eventually, the Flammpanzer III equipped the Panzer Regiment’s (Panzer Abteilung) Flame-thrower Platoons (Panzer-Flamm-Zug), each with seven vehicles. A report dated May 5th 1941 gives the following distribution of the vehicles, along with a single vehicle to Schule Wunsdorf:

A report from 1943, states that from March to December, Flammpanzer III tanks were serving with the following Panzer Divisions: 1st, 6th, 11th, 14th, 24th and Grossdeutschland in Russia and the 16th and 26th in Italy. In July 1943, 41 flame-thrower tanks were reported in service with the 6th, 10th and Grossdeutschland Panzer Divisions in preparation for the attack on Kursk. The Flammpanzer III’s design proved to be unsuccessful and vehicles returned for repair were rebuilt into standard combat tanks or Sturmgeschutz III assault guns / tank destroyers. In November 1944, only 10 out of original 100 were repaired and issued to Panzer-Flamm-Kompanie 351, which saw service as late as April of 1945 with Heeres Gruppe Sud. Today, a Panzerkampfwagen III (Fl) (chassis number 77651) captured in Italy can be seen in Koblenz Museum in Germany after being transferred to the museum from Aberdeen Proving Grounds in U.S.A.

Panzerkampfwagen III Ausf L

In June 1942, the last PzKpfw III model entered production. A new model Ausf N was produced until August 1943 by Henschel, Wegmann, MNH, MIAG and MAN (chassis numbers 73851-77800). Ausf N tanks were produced on Ausf J (3), L (447) and M (213) chassis with total of 663 produced. 37 additional Ausf N tanks were converted from rebuilt older PzKpfw III tanks. The PzKpfw III Ausf N was also known as Sturmpanzer III. The Ausf N was the same as Ausf J, L and M with the main difference being its main armament. It was armed with short 75mm KwK 37 L/24, originally used in PzKpfw IV Ausf A to F1 tanks, which then rearmed with longer 75mm guns. Additional armament consisted of the standard two MG 34 machine guns. The internal ammunition stowage was modified and 56 (based on Ausf L chassis) or 64 (based on Ausf M chassis) rounds were carried. The Ausf N did not have spaced armor as previous models because of the weight of the new 75mm gun. Late production vehicles were fitted with modified type of commander’s cupola with single hatch instead of two-piece one, as well as one-piece side turret hatches. A number of late vehicles were mounted with the commander’s cupola used in PzKpfw IV Ausf G tanks. Vehicles produced from March 1943 were factory mounted with 5mm hull and turret armor skirts (Schurzen). In addition, vehicles produced from early 1943 were factory applied with Zimmerit - anti-magentic paste. PzKpfw III Ausf N tanks were used for close support role. They were either assigned to Tiger Battalions (sPzAbt/sSSPzAbt) as a way to protect them from enemy infantry or to Panzer-Grenadier Divisions. Some sources also state that a variant designated Ausf O existed, although there is no proof of its existence.

The interesting fact is that in 1938, work began on the vehicles which were to replace newly introduced Panzerkampfwagen III and Panzerkampfwagen IV. Daimler-Benz was awarded the contract for a new tank, which was to replace Panzerkampfwagen III - VK 2001 (III). It was a completely new design with new chassis and hull layout. It was also designated as GBK - Kampfwagen des Generalbevollmaechtigen (Battle Tank for the Commission for Standardization of Automotive Designs). The work on this tank stopped in December of 1941 and all efforts were focused on the development of a heavier tank - the Panther.

Some of the later Panzer III variants were fitted with turret mounted storage bins (Gepack Kasten). The canister racks mounted on the turret and/or at the rear of the hull were very common. During the early stages of Operation Barbarossa in 1941, Panzer IIIs were equipped with single-axle trailers carrying extra fuel in order to increase their radius of operation. During production, the PzKpfw III’s design underwent many changes including various modifications made on the turret (e.g. cupola, gun mantlet, vision slots, hatches, armor skirts) and hull (e.g. escape hatch, armor skirts) and superstructure (e.g. air intakes, spaced armor, headlights arrangement) components. Since mid 1943, Panzer IIIs were mounted with Schurzen - 5mm armor skirts. During service and repairs, many Panzer III tanks were up-armored, rearmed and re-equipped with new equipment and components creating completely non-standard variants. Vehicles send to North Africa were equipped with additional air filters and different cooling fan reduction ratio. They were designated as (Tp), Tp being short for Tropisch / Trop / Tropen - tropical.

PzKpfw III Ausf N / (Sturmpanzer III) / Sd.Kfz. 141/2

Panzerkampfwagen III saw action in small numbers during the invasion of Poland in September of 1939. The Panzer III was designed as platoon commander’s vehicle (Zugfuhrerwagen) and was Germany’s first true main/medium battle tank. The design of Panzer III came from lessons learned from the combat tested Panzer I and Panzer II. The Panzer III formed the bulk of the Panzer Divisions’ strength during early years of war. By October 1943, only five Panzer Divisions on the Eastern Front had one or more Panzer Company equipped with Panzer IIIs. By late 1944, only 79 Panzer IIIs were in service with frontline units on the Eastern Front. A number of PzKpfw IIIs remained in service until the end of the war in places like Norway and Holland.

The Panzerkampfwagen III’s production was slow and ceased in August of 1943. In the early years, gaps were filled with the Czech PzKpfw 35(t) and PzKpfw 38(t), which possessed a similar combat value. Its design was also a great help in the development of its bigger brother Panzerkampfwagen IV and shared many common parts with it.

Types Ausf A-J(early) (1936-1941) of Panzer III were called “Short” and types Ausf J(late)-N (1941-1943) were called “Long”. Overall around 6000 Panzerkampfwagen IIIs (long and short) were produced. The majority of PzKpfw IIIs were produced by Alkett along with Daimler-Benz, FAMO, Henschel & Sohn, MAN, MIAG, Waggonfabrik Wegmann and MNH.

Panzer III saw an extensive service on all fronts until late 1943, when it was totally replaced by Panzerkampfwagen IV. As a common practice, the Panzer III’s chassis/components became a base for a few conversions and prototypes. By 1943 standards, the Panzer III was obsolete and lost its combat effectiveness which resulted in many being converted to perform various functions.

From February 1942 to April 1944, 262 Panzerkampfwagen III Ausf E/F/Gs were up-armored and converted into Artillerie Panzerbeobachtungswagen III (Sd.Kfz.143) - observation vehicles which served with Wespe and Hummel batteries until the end of the war. Panzerbeobachtungswagen III had a dummy gun mounted and in the place of original gun, Kugelblende (ballmount) for a 7.92mm MG34 machine gun was installed. The Sd.Kfz.143 had a crew of five and was equipped with powerful radio equipment.

Minenraumpanzer III / Minenraumgerat mit PzKpfw Antrieb.

In 1943, some Ausf L and Ms were converted into turretless Pionierpanzerwagen III - engineer tanks mounted with additional equipment. In mid 1944, 176 Panzer IIIs (including Ausf E, F and G) were converted into Bergepanzer IIIs - recovery vehicles fitted with additional equipment. Also in 1943/44 a number of early Panzer IIIs was converted into Schlepper - artillery tractors and Munitionspanzer - ammunition carriers.

One of the most interesting prototypes based on the Panzer III’s chassis was the Minenraumpanzer III - a mine clearing/mine destroyer tank developed by Krupp. It proved to be unsuccessful and never entered production.

In October of 1943, a prototype of PzKpfw III Ausf N als Schienen-Kettenfahrzeug was tested. Three Ausf Ns (mounted with railway suspension by Sauer Werke of Vienna) were converted to travel by rail at maximum speed of 100km/h. They were to be used to protect the rail network behind the frontlines in the East. Only three prototypes were produced but further development of this project was cancelled.

From June 1938 to February 1943, a number of Panzer IIIs were converted by Daimler-Benz to Panzerbefehlswagens III Ausf D1 (30), Ausf E (45) and Ausf H (175) (Sd.Kfz.266-268) command tanks equipped with extra radios and additional equipment and saw active service until the end of the war. Command tanks were mounted with a dummy gun and were armed only with a single 7.92mm MG machine gun. 185 Panzerbefehlswagen III mit 5cm KwK L/42 (based on Ausf J) and 50 Ausf K (based on Ausf L) were armed with 50mm L/42 and 50mm L/60 guns respectively.

Turrets removed from PzKpfw IIIs converted to other vehicles were used in fortifications of the Atlantic Wall and Hitler’s Line in Italy. In 1945, it was decided to utilize the obsolete PzKpfw III and mount it with Wirbelwind or Ostwind turrets, designated as Flakpanzer III. 90 were ordered but the end of the war terminated the production.

PzKpfw III Ausf G and IV Ausf F1 of Lt. N.Baryshev’s platoon from 107th Independent Tank Battalion, Volkhov Front, July 6th of 1942.

The most interesting field conversion was created by the field workshops of the Afrika Korps in North Africa, who converted a damaged Panzerkampfwagen III Ausf H to 150mm s.I.G.33 gun carrier by using components (such as gun itself, gun shield, superstructure sides with tool stowage and ammunition racks) from Sturmpanzer II Bison (lengthened version).

The Panzerkampfwagen III was also exported to other nations, especially Germany’s Allies or pro-German states. The first country to receive the PzKpfw III was Hungary (10), followed by Romania (11 Ausf N), Bulgaria (10 Ausf N) and Slovakia (7 Ausf N). A small number of Ausf L and N tanks was also exported to Croatia. A large number (56) was ordered by Turkey but the transaction was never finalized due to the war situation, although supposedly some (20-22?) were delivered.

From 1941 to 1943, Russians captured large numbers of PzKpfw III, Sturmgeschutz III and PzKpfw IV. Some were pressed into temporary service (e.g. being used as “Trojan Horses” or as “bait”) , while some were converted to assault guns designated SU-76i and SG-122A.

An interesting fact is that the Polish Tank Platoon of the Carpathian Lancers received captured PzKpfw III for training purposes, while in Egypt in August of 1942.

The most successful conversion based on the Panzerkampfwagen III’s chassis was the Sturmgeschutz III - assault gun/tank destroyer series - which remained in service with the Finnish Army as late as 1967.

After the war ended, some 32 PzKpfw III were used by Norway along with Stug III Ausf Gs.

A small number of PzKpfw III tanks was also used by Czechoslovakia, including four rebuild Flammpanzer III tanks.

The Panzerkampfwagen III gained a reputation for being a highly reliable and effective vehicle, which shaped tank development plans of both German and Allied tank builders. It was the best German tank in the first part of the war, but by 1943 it was largely obsolete.

This U-Panzer belonged to the 18th Panzer Division’s 18th Panzer Regiment. This photo was taken during the crossing of the River Bug at Patulin on 22nd June of 1941. During the preparation for the invasion of England - Operation Seelöwe (Sealion) - Panzer IIIs and Panzer IVs were converted into submersible tanks able to travel on the bottom of a body of water at the depths of 6 to 15 meters. From June to October of 1940, 160 Panzer III Ausf F/G/H and 8 Panzerbefehlswagen III Ausf E along with 42 Panzer IV Ausf Ds were converted into U-Panzers / Tauchpanzers. After extensive tests and modifications U-Panzer were ready for action. Since Operation Sealion was never realized, Tauchpanzer IIIs and IVs were used during Operation Barbarossa (crossing river Bug at Patulin), in service with 3rd (6th Panzer Regiment) and 18th Panzer Division. It was also planned to use U-Panzers in the aborted invasion on the island of Malta.

Specifications

Conversions

· PzKpfw III (Flamm) Ausf. M (Sd. Kfz. 141/3) - flame-thrower tank,

· Befehlswagen III Ausf. D1 (Sd.Kfz 267-268) - command tank,

· Befehlswagen III Ausf. E (Sd. Kfz. 266-268) - command tank,

· Befehlswagen III Ausf. H (Sd. Kfz. 266-268) - command tank,

· Befehlswagen III Ausf. K - command tank,

· Beobachtungswagen III - observation vehicle (Sd.Kfz.143),

· Bergepanzer III (Sd. Kfz. 143) - recovery vehicle,

· Sturmgeschütz III Ausf A to E (Sd.Kfz.141),

· Sturmgeschütz III (40) Ausf F/G (Sd.Kfz.141/2),

· Sturmhaubitze 42 (Sd.Kfz. 142/2) 105mm L/28 (L/30) - assault howitzer,

· Stug 33 - 150mm howitzer carrier - infantry support,

· Munitionspanzerwagen III Ausf E/F/G - ammo carrier,

· Munition Schlepper - ammo carrier for Ferdinand/Elephant units,

· Pionierpanzerwagen III - engineer’s tank,

· Panzer III Ausf N Schienen-Kettenfahrzeug - rail tank,

· PzKpfw III Ausf G/H mit Schachtellaufwerk - prototype / dozer tank,

· Panzer III Ausf. E(U) (37mm gun) - submersible tank,

· Panzer III Ausf. F(U) (50mm L/42 gun) - submersible tank,

· Panzer III Ausf D1(U) - submersible command tank,

· Panzer III Ausf H(U) - submersible command tank,

· Minenraumpanzer III - mine clearing vehicle (prototype),

· Flakpanzer III (planned),

· Artillerie Schlepper - artillery tractor.

***

An engineering report on samples of German natural and artificial rubber from a Panzer III, appeared Tactical and Technical Trends, No. 33, September 9, 1943.

GERMAN TANK RUBBER ANALYSIS

Tactical and Technical Trends, No. 33, September 9, 1943

Analysis by British engineers of samples of natural and artificial rubber taken from the PzKw 3 tanks discloses some interesting points which are worth recording.

Two very similar articles, i.e. a vision forehead pad and a cupola pad of a 1940 model of this tank proved to be very different when analyzed. The former was made of natural rubber and was secured to the metal by the brass plating process. The cupola pad, on the other hand, was made from synthetic rubber and was attached to the metal by an adhesive paint. These samples confirm the previous supposition that the Germans have not yet learned how to make an efficient joint between synthetic rubber and metal.

The most interesting sample, however, was a section of a bogie wheel tire from a PzKw 3 tank (probably 1942). This sample proved to be made of synthetic rubber. This is said to be the first evidence received by the British authorities of this material being used by the Germans for solid tires. It seems to show that the Germans have made sufficient technical progress to overcome the heating difficulties previously arising when synthetic rubber was used for this type of work. The method of adhesion to the metal band was by means of an intermediate layer of hard, probably natural rubber.

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Panzerbefehlswagen (command tank) III ausf E or F in Greece, fitted with a 37 mm gun and two coaxial machine guns (1941).

ARMOUR

The Panzer III Ausf. A through C had 15 mm (0.59 in) of homogeneous steel armor on all sides with 10 mm (0.39 in) on the top and 5 mm (0.20 in) on the bottom. This was quickly determined to be insufficient, and was upgraded to 30 mm (1.18 in) on the front, sides and rear in the Ausf. D, E, F, and G models, with the H model having a second 30 mm (1.18 in) layer of face-hardened steel applied to the front and rear hull. The Ausf. J model had a solid 50 mm (1.97 in) plate on the front and rear, while the Ausf. J¹, L, and the M models had an additional layer of 20 mm (0.79 in) of armor on the front hull and turret. This additional frontal armor gave the Panzer III frontal protection from most British and Soviet anti-tank guns at all but close ranges. The sides were still vulnerable to many enemy weapons including anti-tank rifles at close ranges

The Panzer III was intended to fight other tanks; in the initial design stage a 50-mm (1.97 in) cannon was specified. However, the infantry at the time were being equipped with the 37-mm (1.46 in) PaK 36, and it was thought that in the interest of standardization the tanks should carry the same armament. As a compromise, the turret ring was made large enough to accommodate a 50-mm (1.97 in) cannon should a future upgrade be required. This single decision would later assure the Panzer III a prolonged life in the German Army.

The Ausf. A to early Ausf. F were equipped with a 3.7 cm KwK 36 L/46.5 which proved adequate during the campaigns of 1939 and 1940 but the later Ausf. F to Ausf. J were upgraded with the 5 cm KwK 38 L/42 and the Ausf. J¹ to M with the longer 5 cm KwK 39 L/60 cannon in response to increasingly better armed and armored opponents.

By 1942, the Panzer IV was becoming Germany’s main medium tank because of its better upgrade potential. The Panzer III remained in production as a close support vehicle. The Ausf. N model mounted a low-velocity 7.5 cm KwK 37 L/24 cannon - the same used by the early Panzer IV Ausf. A to Ausf. F models. These guns had originally been fitted to older Panzer IV Ausf A to F1 models and had been placed into storage when those tanks had also been up armed to longer versions of the 75mm gun.

All early models up to and including the Ausf. F had two 7.92-mm (0.31 in) Maschinengewehr 34 machine guns mounted coaxially with the main gun, and a similar weapon in a hull mount. Models from the Ausf. G and later had a single coaxial MG34 and the hull MG34.

MOBILITY

The Panzer III Ausf. A through C were powered by a 250 metric horsepower (183.87 kW), 12-cylinder Maybach HL 108 TR engine, giving a top speed of 32 kilometres per hour (19.88 mph) and a range of 150 kilometres (93.21 mi). All later models were powered by the 300 metric horsepower (220.65 kW), 12-cylinder Maybach HL 120 TRM engine. Top speed varied, depending on the transmission and weight, but was around 40 kilometres per hour (24.85 mph). The range was generally around 155 kilometres (96.31 mi).

Combat Use

The Panzer III was used in the campaigns against Poland, France, the Soviet Union and in North Africa. A handful were still in use in Normandy, Anzio, Finland and in Operation Market Garden in 1944.

In the Polish and French campaigns, the Panzer III formed a small part of the German armored forces. Only a few hundred Ausf. A through F were available in these campaigns, most armed with the 37-mm (1.46 in) gun. They were the best medium tank available to the Germans and outclassed most of their opponents such as the Polish 7TP, French R-35 and H-35 light tanks.

The crew of a Panzer III of the 2nd SS Panzer Division Das Reich rest after heavy fighting in the Battle of Kursk.

Around the time of Operation Barbarossa, the Panzer III was numerically the most important German tank. At this time the majority of the available tanks (including re-armed Ausf. E and F, plus new Ausf. G and H models) mounted the 50-mm (1.97 in) KwK 38 L/42 cannon which also equipped the majority of the tanks in North Africa. Initially, the Panzer IIIs were outclassed and outnumbered by Soviet T-34 and KV tanks. However, the most numerous Soviet tanks were the T-26 and BT tanks. This, along with superior German tactical skill, crew training, and the good ergonomics of the Panzer III all contributed to a rough 6:1 favourable kill ratio for German tanks of all types in 1941.

With the appearance of the T-34 and KV tanks, rearming the Panzer III with a longer, more powerful 50-mm (1.97 in) cannon was prioritised. The T-34 was generally invulnerable in frontal engagements with the Panzer III until the 50 mm KwK 39 L/60 gun was introduced on the Panzer III Ausf. J¹ in the spring of 1942 (the gun was based on infantry’s 50 mm Pak 38 L/60). This could penetrate the T-34 frontally at ranges under 500 metres (1,600 ft). Against the KV tanks it was a threat if armed with special high velocity tungsten rounds. In addition, to counter antitank rifles, in 1943 the Ausf. L version began the use of spaced armor skirts (schürzen) around the turret and on the hull sides. However, due to the introduction of the upgunned and uparmored Panzer IV, the Panzer III was, after the Battle of Kursk, relegated to secondary roles, such as training, and it was replaced as the main German medium tank by the Panzer IV and the Panther.

The Panzer III chassis was the basis for the turretless Sturmgeschütz III assault gun, one of the most successful self-propelled guns of the war, and the single most-produced German armored fighting vehicle design of World War II.

By the end of the war, the Pz.III had almost no frontline use and many vehicles had been returned to the factories for conversion into StuG assault guns, which were in high demand due to the defensive warfare style adopted by the German Army by then.

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The following report written by Hauptmann Oehme, the commander of the 8.Kompanie/Panzer-Regiment 3, relates his experience in attempting to knock out T34 and KW-I tanks:

Combat Report for the Period of 11 through 17 August 1942

At about 1800 hours, I received the order to drive to Jelnja to support the Gruppe von Bisehoffshausen with the Panzers that had just been repaired and the four Pz.Kpfw.IV (7.5 cm Kw.K.40 L/43) that had just arrived.

The Panzer-Kompanie counterattacked JeInja, which was surrounded by our Panzers and taken under heavy fire by all of the Panzers. The front elements of the Russians pulled back and most of the houses in the village went up in flames. It was observed that two T-34s drove off in reverse out of burning sheds.

As dawn broke, the Russians renewed the attack with tank and infantry forces. The tanks were immediately spotted and two T-34s on the road were knocked out at a range of about 300 meters. The rest of the tanks must have quickly retreated, as determined by the noise from their engines.

During the evening hours of 13th August, the Russians again attacked with tanks and a few infantry riding on them. In spite of night falling, a further two T34s and a KW-I were knocked out of which two enemy tanks brightly burned, upon which the rest of the tanks turned back. The attack was repulsed.

Panzer III advancing deeper into Russia, during 1941.

During the night, the opponent with tanks took up positions in the depression by Shulebino and at dawn attempted to break through the woods by Point 208. At the same time eight to ten KW-I attacked on the road. Of these, two were knocked out in our position by the Pz.Kpfw.IV with a long gun at a range of 15 to 20 meters. The rest were convinced to turn back. It should be noted that it was necessary to use about eight Hohlraumgranaten (shaped charge shells) to set each of the KW-I on fire. At Point 208, three T34s managed to break into the position but didn’t exploit the opportunity any further. The company commander of the infantry urgently requested Panzer support because these enemy tanks had hidden in the woods. One Pz.Kpfw.IV (7.5 cm Kw.K. L/24) and two Pz.Kpfw.III (5 cm Kw.K. L/42) were sent to the area where the enemy tanks had broken in.

In the afternoon, the Russians again attacked with strong tank forces. This time his attempt occurred south of the road. Several tanks landed in the swamp and remained stuck there. In the evening, these tanks were knocked out by the 5.Kompanie/Panzer-Regiment 3, while on the road four additional KW-I were knocked out by the 8.Kompanie. An 8.8 cm Flak gun had a large part in this last defensive battle. This gun was located in an alley south of the road, fell out when damaged by gun fire, and was pulled back.

On this day, several smaller Russian tanks were knocked out that had attacked separately. In addition a Pz.Kpfw.IV (7.5 cm Kw.K.40 L/43) was knocked out by a KW-I. One of the crew was killed, two severely wounded, and one lightly wounded.

Another Pz.Kpfw.IV (7.5 cm Kw.K.40 L/43) fought still another T34 but was itself knocked out. The Pz.Kpfw.IV immediately burned out. The commander and gunner were wounded, three of the crew were killed immediately. During these defensive actions from 11 to 17 August 1942, the 8.Kompanie knocked out 45 enemy tanks, of which 11 were T60s, and the rest T34s and KW-Is.

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AMMUNITION STORAGE

The ammunition were laid out vertically except for those located under the seat of the gunner. The base of the round was laid out in a cavity in the floor of the rack and the point was maintained in place by a spring clip. This provision was effective in general except for certain rounds, difficult to reach. The right lower rack and two back-left racks had sliding doors (sensitive to the sand grains) then the left lower rack was equipped with an articulated door. The tanks armed with the 50mm KwK L/60 50mm laid out their ammunition in a horizontal disposition, which was easier for employment. The rounds used by L/60 were longer, which limited the number of rounds carried in the tank to 78 rounds.

A Panzer III in action during the Demjansk pocket battle.

For the vehicles armed with the gun of 50mm KwK L/42 the provision of the ammunition was 99 rounds stored as follows:

· 5 rounds under the seat of the gunner

· 22 rounds in a rack located in the back-right corner of the compartment

· 12 rounds in a rack located above this last

· 36 rounds in a rack located in the back-left corner of the compartment

· 24 rounds in a rack located above this last.

VARIANTS

· Panzer III Ausf. A - Prototype; 10 produced in 1937, only 8 armed and saw service in Poland.

· Panzer III Ausf. B, C - Prototype; 15 of each produced in 1937, some of each saw service in Poland.

· Panzer III Ausf. D - Prototype; 55 produced in 1938, only 30 armed and saw service in Poland and Norway.

· Panzer III Ausf. E, F - Production models 1939-1940. Armed with 3.7 cm KwK 36 L/46.5 (later 5 cm KwK 38 L/42) guns. 531 produced.

· Panzer III Ausf. G - More armor on gun mantlet. Armed with 3.7 cm KwK 36 L/46.5 (later 5 cm KwK 38 L/42) gun. 600 produced in 1940-1941.

· Panzer III Ausf. H - Minor modifications. Bolt-on armor added to front and rear hull (30 mm + 30 mm plates). 308 produced in 1940-1941.

· Panzer III Ausf. I - Variant mentioned in Allied intelligence reports but not an actual existing vehicle.

· Panzer III Ausf. J - The hull was lengthened. Front armor increased to 50 mm plate. 482 produced in 1941.

· Panzer III Ausf. J¹ - Equipped with the longer and more powerful 5 cm KwK 39 L/60 gun. 1,067 produced in late 1941 to mid 1942.

· Panzer III Ausf. K - Panzerbefehlswagen command tank variant with a modified turret. Carried actual main armament rather than a dummy gun as found on other Panzer III command versions.

· Panzer III Ausf. L - Uparmored to 50 mm + 20 mm plates. 653 produced in 1942.

· Panzer III Ausf. M - Minor modifications such as deep-wading exhaust and schurzen. 250 produced in 1942-1943.

· Panzer III Ausf. N - Armed with a short barreled 7.5 cm KwK 37 L/24 gun, due to 7.5 cm gun’s ability to fire HEAT rounds. 700 re-equipped J/L/M models in 1942-1943.

CONVERSIONS

· PzKfw III (Flamm) Ausf. M (Sd. Kfz 141/3) - flame-thrower

· Befehlswagen III Ausf. Dl (Sd. Kfz 267-268) - command tank

· Befehlswagen III Ausf. E (Sd. Kfz 267-268) - command tank

· Befehlswagen III Ausf. H (Sd. Kfz 266-268) - command tank

· Befehlswagen III Ausf. K - command tank

· Beobachtungswagen III - observation vehicle (Sd. Kfz 143)

The Tauchpanzer was developed in mid-1940 for the proposed invasion of England (Sea Lion). The Pz Kpfw III were modified and provided with a submersion kit. Air-intakes were fitted with locking covers, and the exhaust was fitted with non-return valves. The cupola, gun mantlet and hull MG were sealed with waterproof fabric covers. An inflatable rubber tube surrounded the turret ring. While submerged, the tank drew air through a pipe from a float carrying a snorkel device and radio antenna which remained on the surface. A gyro-compass was used for underwater navigation. The Tauchpanzer could operate in depths of up to 15 metres. A vessel with a hinged ramp was used to disembark the Tauchpanzer at a suitable distance from the shore. With the cancellation of ‘Sea Lion’, the Tauchpanzer were no longer required in quite the same form. At Milowitz near Prague, in the spring of 1941, most of the tanks were modified to make them suitable for river crossing, with a fixed snorkel pipe attached through the commander’s cupola.

Grenadiers and Panzer III in the snow during the winter of 1942.

From July 1940, four sections of volunteers from existing Panzer regiments were trained on the Island of Sylt, and the Tauchpanzer were to be ready for operations at Putlos by 10 August. In mid-October, three of these sections were attached to the 18th Panzer Division, and the remainder went to the 6th Panzer Regiment of the 3rd Panzer Division. On 22 June 1941, the Tauchpanzer of the 18th Panzer Division crossed the River Bug at Patulin.

During September and October 1940 volunteers of the 2nd Tank Regiment in Putlos were formed into Tank Battalion A and trained for Operation Sea Lion, the invasion of Great Britain. Two other special formations, Tank Battalions Band C, were being raised at the same time and the same place. These units later formed the 18th Tank Regiment of the 18th Panzer Division and adapted the Pz Kpfw III and IV for submerged wading. The following measures were taken. All openings, vision slits, flaps, etc, were made watertight with sealing compounds and cable tar, the turret entry ports were bolted from the inside and air intake openings for the engine completely closed. A rubber cover sheet was fixed over the mantlet, the commander’s cupola and the bow machine gun. An ignition wire blew off the covering sheet upon surfacing and left the vehicle ready for action. Between the hull and the turret there was a rubber sealing ring which, when inflated, prevented the water from entering. The fresh air supply was maintained by a wire-bound rubber trunk with a diameter at about 20 cm, 18 metres long. To one end of this tube was fitted a buoy with attached antennae. The exhaust pipes were fitted with high-pressure non-return relief valves. When travelling submerged sea water was used to cool the engine and seepage was removed by a bilge pump. The maximum diving depth was 15 metres. Three metres of the air tube’s 18 metre length was available as a safety measure. These submersible tanks were to be launched from barges or lighters. They slid into the water down an elongated ramp made of channel plates. Directing was achieved by radio orders from a command vessel to the submerged vehicle. Underwater navigation was carried out by means of a gyro compass and the crew was equipped with escape apparatus. The submerged machines were relatively easy to steer as buoyancy lightened them. After Operation Sea Lion was abandoned these vehicles were eventually used operationally during the Russian campaign in 1941 for the crossing of the River Bug.

A Panzer III with the 37mm main armament rolls past a blazing British tank North Africa, 1941.

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A short intelligence report on German tanks modified for submersion, from Tactical and Technical Trends, July 29, 1943.

GERMAN SUBMERSIBLE TANKS

Tactical and Technical Trends, July 29, 1943

The delays and difficulties involved in the transport of tanks across the rivers of Eastern Europe have no doubt forced the Germans to consider very seriously all possible devices for enabling their standard tanks to cross such water obstacles under their own power.

By the summer of 1941, the weight of the PzKw 3 had already been increased by the fitting of additional armor, and it must have been clear that future developments in armor and armament would necessarily involve still further increases in the weight of this tank. While the trend towards increased weight was in many ways disadvantageous, it was definitely helpful in overcoming one of the major difficulties hitherto encountered in adapting standard tanks for submersion, namely the difficulty of obtaining sufficient track adhesion.

Prototype development of large interleaving road wheels, using a Pz Kpfw III Ausf H (7 ZW) as the basis of the conversion. The three prototypes were built late in 1940 was used for training purposes after testing had been completed. Further development was halted and in 1943/44, prototypes were fitted with dozers and were used to clean up the streets of bombed cities. This suspension was later adopted in the Tiger and Panther.

It is therefore not surprising that the Germans, in the early stages of their campaign in Russia, were actively experimenting with standard PzKw 3’s modified for submersion. These experiments met with a certain degree of success, and under-water river crossings are reported to have been made with these modified tanks under service conditions. The measures employed, according to a Russian source, included the sealing of all joints and openings in the tank with india rubber, and the fitting of a flexible air pipe, the free end of which was attached to a float. The supply of air for the crew as well as for the engine was provided for by this flexible pipe. The maximum depth of submersion was 16 feet and the time taken by trained crews to prepare the tanks was about 24 hours.

In April 1943, a PzKw 3 Model M examined in North Africa was found to be permanently modified or immersion, if not submersion. There was no mention in the report on this tank of a flexible pipe with float, but this may have been destroyed, since the tank, when examined, had been completely burnt out.

The engine air louvres were provided with cover plates having rubber sealing strips around their edges. These cover plates, which were normally held open by strong springs, could be locked in the closed position before submersion. After submersion, the springs could be released by controls from inside the tank. When submerged, air for the carburettor and for the cooling fans was apparently drawn from the fighting compartment. If, therefore, a flexible pipe were used with this tank, no doubt its purpose would be to supply air to the fighting compartment to replace that withdrawn for the carburettor and cooling fans. The two exhaust pipes led to a single silencer mounted high on the tail plate with its outlet at the top. This outlet was fitted a spring-loaded non-return valve, which during normal running could be secured in a fully open position.

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The Japanese government bought two Panzer III’s from their German Allies during the war. This was for reverse engineering purposes, since Japan put more emphasis on the development of new military aircraft and naval technology and relatively little on the development of new tanks. The vehicles apparently weren’t delivered until 1943 by which time much of the Panzer III’s technology had arguably already become obsolete.