Tiger II

Development

Development of a heavy tank design had been initiated in 1937; the initial design contract was awarded to Henschel. Another design contract followed in 1939, and was given to Porsche. Both prototype series used the same turret design from Krupp; the main differences were in the hull, transmission, suspension and automotive features.

The Henschel version used a conventional hull design with sloped armour resembling the layout of the Panther tank. It had a rear-mounted engine and used nine steel-tired, eighty-centimeter-diameter overlapping road wheels per side with internal springing, mounted on transverse torsion bars, in a similar manner to the original Henschel-designed Tiger I. To simplify maintenance, however, as when the same steel-tired road wheels were used on later Tiger I hulls, the wheels were only overlapping without being interleaved — the full Schachtellaufwerk rubber-rimmed roadwheel system that had been in use on nearly all German half-tracks used the interleaved design, later inherited by the early production versions of the Tiger I and Panther.

The Porsche hull designs included a rear-mounted turret and a mid-mounted engine. The suspension was the same as on the Elefant tank destroyer. This had six road wheels per side mounted in paired bogies sprung with short longitudinal torsion bars that were integral to the wheel pair; this saved internal space and facilitated repairs. One Porsche version had a gasoline-electric drive (fundamentally identical to a Diesel-electric transmission, only using a gasoline-fueled engine as the prime mover), similar to a gasoline-electric hybrid but without a storage battery; two separate drive trains in parallel, one per side of the tank, each consisting of a hybrid drive train; gasoline engine – electric generator – electric motor – drive sprocket. This method of propulsion had been attempted before on the Tiger (P) (later Elefant prototypes) and in some US designs, but had never been put into production. The Porsche suspension were later used on a few of the later Jagdtiger tank destroyers. Another proposal was to use hydraulic drives. Dr. Porsche's unorthodox designs gathered little favour.

Design

Henschel won the design contract, and all Tiger IIs were produced by the firm. Two turret designs were used in production vehicles. The initial design is often misleadingly called the "Porsche" turret due to the belief that it was designed by Porsche for their prototype; in fact it was the initial Krupp design for both prototypes. This turret had a rounded front and steeply sloped sides, with a difficult-to-manufacture curved bulge on the turret's left side to accommodate the commander's cupola. Fifty early turrets were mounted to Henschel's hull and used in action. The more common "production" turret, sometimes called the "Henschel" turret, was simplified with a significantly thicker flat face, no shot trap (created by the curved face of the earlier turret), and less-steeply sloped sides, which prevented the need for a bulge for the commander's cupola, and added additional room for ammunition storage.

The turrets were designed to mount the 8.8 cm KwK 43 L/71 gun. Combined with the Turmzielfernrohr 9d (German "turret telescopic sight") monocular sight by Leitz, which all but a few early Tiger IIs used, it was a very accurate and deadly weapon. During practice, the estimated probability of a first round hit on a 2 m (6 ft 7 in) high, 2.5 m (8 ft 2 in) wide target only dropped below 100 percent at ranges beyond 1,000 m (0.62 mi), to 95–97 percent at 1,500 metres (0.93 mi) and 85–87 percent at 2,000 m (1.2 mi), depending on ammunition type. Recorded combat performance was lower, but still over 80 percent at 1,000 m, in the 60s at 1,500 m and the 40s at 2,000 m. Penetration of armoured plate inclined at 30 degrees was 202 and 132 mm (8.0 and 5.2 in) at 100 m (110 yd) and 2,000 m (1.2 mi) respectively for the Panzergranate 39/43 projectile (PzGr—armour-piercing shell), and 238 and 153 mm (9.4 and 6.0 in) for the PzGr. 40/43 projectile between the same ranges. The Sprenggranate 43 (SpGr) high-explosive round was available for soft targets, or the Hohlgranate or Hohlgeschoss 39 (HlGr—HEAT or High-explosive anti-tank warhead) round, which had 90 mm (3.5 in) penetration at any range, could be used as a dual-purpose munition against soft or armoured targets.

Powered turret traverse was provided by the variable speed Boehringer-Sturm L4S hydraulic motor, which was driven from the main engine by a secondary drive shaft. A high and a low speed setting was available to the gunner via a lever on his right. The turret could be rotated 360 degrees in 60 seconds in low gear independent of engine rpm, in 19 seconds with the high speed setting and engine at 2000 rpm, and within 10 seconds at the maximum allowable engine speed of 3000 rpm. The direction and speed of traverse were controlled by the gunner through foot pedals, or a control lever near his left arm. If power was lost, such as when the tank ran out of fuel, the turret could be slowly traversed by hand, assisted by the loader who had an additional wheel. Two full turns of the wheel were necessary for a one degree turn of the turret, with a total of 720 turns for a full circle.

Like all German tanks, the Tiger II had a petrol engine; in this case the same 700 PS (690 hp, 515 kW) V-12 Maybach HL 230 P30 which powered the much lighter Panther and Tiger I tanks. The Tiger II was under-powered, like many other heavy tanks of World War II, and consumed a lot of fuel, which was in short supply for the Germans. The transmission was the Maybach OLVAR EG 40 12 16 Model B, giving eight forward gears and four reverse, which drove the steering gear. This was the Henschel L 801, a double radius design which proved susceptible to failure. Transverse torsion bar suspension supported the hull on nine axles per side. Overlapped 800 mm (31 in) diameter road wheels with rubber cushions and steel tyres rode inside the tracks.

Like the Tiger I, each tank was issued with two sets of tracks: a normal "battle track" and a narrower "transport" version used during rail movement. The transport tracks reduced the overall width of the load and could be used to drive the tank short distances on firm ground. The crew were expected to change to normal battle tracks as soon as the tank was unloaded. Ground pressure was 0.76 kg/cm² (10.8 psi).

Command variant

The command variant of the Tiger II was designated Panzerbefehlswagen Tiger Ausf. B. It had two versions, Sd.Kfz. 267 and Sd.Kfz. 268. These carried only 63 rounds of 8.8 cm ammunition to provide room to accommodate the extra radios and equipment, and had additional armour on the engine compartment. The Sd.Kfz. 267 was to have used FuG 8 and FuG 5 radio sets, with the most notable external changes being a two metre long rod antenna mounted on the turret roof and a Sternantenne D ("Star antenna D"), mounted on an insulated base (the 105 mm Antennenfuß Nr. 1), which was protected by a large armoured cylinder. This equipment was located on the rear decking in a position originally used for deep-wading equipment. The Sd.Kfz. 268 used FuG 7 and FuG 5 radios with a two-metre rod antenna mounted on the turret roof and a 1.4 metre rod antenna mounted on the rear deck.

Production

The Tiger II was developed late in the war and built in relatively small numbers. Orders were placed for 1,500 Tiger IIs — slightly more than the 1,347 Tiger I tanks produced — but production was severely disrupted by Allied bombing raids. Among others, five raids between 22 September and 7 October 1944 destroyed 95 percent of the floor area of the Henschel plant. It is estimated that this caused the loss in production of some 657 Tiger IIs. Only 492 units were produced: one in 1943, 379 in 1944, and 112 in 1945. Full production ran from mid-1944 to the end of the war.

The Tiger II served as the basis for one production variant, the Jagdtiger casemated tank destroyer, and a proposed Grille 17/21/30/42 self-propelled mount for heavy guns which never reached production.

Proposed upgrades

The HL234, an engine born from the developments initiated by attempting to convert the Maybach HL230 to fuel injection, would have increased the power to about 800 to 900 PS (hp). The Entwicklungskommission Panzer unanimously decided that HL234 be immediately included in the engine design and procurement program. The AK-7-200 was also explored as an alternative to the Olvar-B drive train, but Waffenamt research and development department Wa Prüf 6 found that it offered inferior driving characteristics and so the Olvar-B was retained. Krupp proposed mounting a new main weapon, the 10.5 cm KwK L/68. Wa Prüf 6 was not supportive of this as the Heer had not accepted the cannon itself. Other suggested improvements included stabilised sights, a stabilised main gun, an automatic ammunition feed, a Zeiss stereoscopic range finder, heated crew compartment, stowage for an additional 12 rounds, and an overpressure & air filtration system to protect against poison gas. However, these also never got beyond the proposal stage or did not enter production before the war ended.

Specifications

Organisation

Apart from research, training, and a five-tank attachment to the Panzer Lehr, the Tiger II was only issued to heavy tank battalions (schwere Panzer-Abteilungen) of the German Army (Heer), or Waffen-SS.

A standard battalion (Abteilung) comprised 45 tanks:

Units that used the Tiger II were as follows:

Reliability and mobility

Early Tiger IIs proved unreliable, owing principally to leaking seals and gaskets, and an overburdened drive train originally intended for a lighter vehicle. The double radius steering gear was initially particularly prone to failure. Lack of crew training could amplify this problem; drivers originally given only limited training on other tanks were often sent directly to operational units already on their way to the front.

The Schwere Heeres Panzer Abteilung 501 (s.H.Pz.Abt. 501) arrived on the Eastern Front with only eight out of 45 tanks operational; these faults were mostly due to drive-train failures. The first five Tiger IIs delivered to the Panzer Lehr Division broke down before they could be used in combat, and were destroyed to prevent capture.

The introduction of modified seals, gaskets and drive train components, as well as improved driver training and sufficient maintenance improved the tank's mechanical reliability. Statistics from 15 March 1945 show reliability rates of 59 percent for the Tiger, almost equal to the 62 percent of the Panzer IV and better than the 48 percent of the Panther were operational by this period.

Not withstanding its initial reliability problems, the Tiger II was remarkably agile for such a heavy vehicle. Contemporary German records and testing results indicate that its tactical mobility was as good as or better than most German or Allied tanks.

Combat history

The first combat use of the Tiger II was by the 1st Company of the 503rd Heavy Panzer Battalion (s.H.Pz.Abt. 503) during the Battle of Normandy, opposing Operation Atlantic between Troarn and Demouville on 18 July 1944. Two were lost in combat, while the company commander's tank became irrecoverably trapped after falling into a bomb crater created during Operation Goodwood.

On the Eastern Front, it was first used on 12 August 1944 by the 501st Heavy Panzer Battalion (s.H.Pz.Abt. 501) resisting the Lvov–Sandomierz Offensive. It attacked the Soviet bridgehead over the Vistula River near Baranów Sandomierski. On the road to Oględów, three Tiger IIs were destroyed in an ambush by a few T-34-85s. Because these German tanks suffered ammunition explosions, which caused many crew fatalities, main gun rounds were no longer allowed to be stowed within the turret, reducing capacity to 68. Up to fourteen Tiger IIs of the 501st were lost in the area between 12 and 13 August to ambushes and flank attacks by Soviet T-34-85 and IS-2 tanks, and ISU-122 assault guns in inconvenient sandy terrain.

On 15 October 1944, Tiger IIs of 503rd Heavy Panzer Battalion played a crucial role during Operation Panzerfaust, supporting Otto Skorzeny's troops in taking the Hungarian capital of Budapest, which ensured that the country remained with the Axis until the end of the war. The 503rd then took part in the Battle of Debrecen. The 503rd remained in the Hungarian theater of operations for 166 days, during which it accounted for at least 121 Soviet tanks, 244 anti-tank guns and artillery pieces, five aircraft and a train. This was set against the loss of 25 Tiger IIs; ten were knocked out by Soviet troops and burned out, two were sent back to Vienna for a factory overhaul, while thirteen were blown up by their crews for various reasons, usually to prevent them from falling into enemy hands. Kurt Knispel, the highest scoring tank ace of all time (162 enemy AFVs destroyed), also served with the 503rd, and was killed in action on 29 April 1945 in his Tiger II.

The Tiger II was also used in significant numbers, distributed into four heavy panzer battalions, during the Ardennes Offensive (also known as the Battle of the Bulge) of December 1944. At least 150 Tiger IIs were present, nearly a third of total production, and most were lost during the course of the offensive. During the Battle of St. Vith a M8 Greyhound armoured car destroyed a Tiger II after getting in behind it on the Schonberg Road, though the commander tried to traverse his turret to engage the M8. The M8 fired three 37 mm rounds into the relatively thin rear armor of the Tiger from only 25 yd (23 m), setting it on fire: There was a muffled explosion, followed by flames which billowed out of the turret and engine port.

Some Tiger IIs were also present during the Soviet Vistula–Oder and East Prussian Offensives in January 1945, as well as the German Lake Balaton Offensive in Hungary in March 1945, the Battle of the Seelow Heights in April 1945, and the Battle of Berlin at the end of the war.

The 103rd SS Heavy Panzer Battalion (s.SS Pz.Abt. 503) claimed approximately 500 kills in the period from January to April 1945 on the Eastern Front for the loss of 45 Tiger IIs (most of which were abandoned and destroyed by their own crews after mechanical breakdowns or for lack of fuel).

Gun and armour performance

The heavy armour and powerful long-range gun gave the Tiger II an advantage against all opposing Western Allied and Soviet tanks attempting to engage it from head on. This was especially true on the Western Front where, until the arrival of the few M26 Pershings in 1945, neither the British nor US forces brought heavy tanks into service. A Wa Prüf 1 report estimated that the Tiger II's frontal aspect was impervious to the 122 mm D-25T, the heaviest although not the best penetrating tank gun on the Allied side. On the other hand, an R.A.C 3.d. document of February 1945 estimated that the British QF 17-pounder (76.2 mm) gun, using armour-piercing discarding sabot shot was theoretically capable of penetrating the front of the Tiger II's turret and nose (lower front hull) at 1,100 and 1,200 yd (1,000 and 1,100 m) respectively although, given the lack of a stated angle, this is presumably at the ideal 90 degrees angle. As a result of its thick frontal armour, flanking manoeuvres were most often used against the Tiger II to attempt a shot at the thinner side and rear armour, giving a tactical advantage to the Tiger II in most engagements. Moreover, the main armament of the Tiger II was capable of knocking out any Allied tank frontally at ranges exceeding 2.5 kilometres (1.6 mi), well beyond the effective range of Allied tank guns.

Soviet wartime testing

During August 1944, two Tiger Ausf B tanks were captured by the Soviets near Sandomierz, and were soon moved to the testing grounds at Kubinka. During the transfer, the two tanks suffered from various mechanical breakdowns; the cooling system was insufficient for the excessively hot weather, where the engine tended to overheat and cause a consequential failure of the gearbox. The right suspension of one of the tanks had to be completely replaced, and its full functionality could not be re-established. The tank broke down again every 10–15 km. The 8.8 cm KwK 43 gave positive results in penetration and accuracy, which were on par with the 122 mm D-25T. It proved capable of passing completely through its "colleague", a Tiger Ausf B's turret at a range of 400 m. The armour of one vehicle was tested by firing at it with shells between 100 and 152 mm calibre. The welding was, despite careful workmanship, significantly worse than on similar designs. As a result, even when shells did not penetrate the armour, there was often a large amount of spalling from the inside of the plates, which damaged the transmission and rendered the tank inoperable. Further testing showed that the armour plate itself exhibited deficiencies in quality compared to earlier German tanks such as the Tiger I and Panther. Analysis of the Tiger Ausf B armour plate showed an absence of molybdenum (ascribed to a loss of supply, being replaced by vanadium), giving the armour low malleability.

The expanded firing test states that the АР projectiles from the 100 mm BS-3 and 122 mm A-19 gun penetrated a Tiger Ausf B's turret at ranges of 1000–1500 metres, which suggests a quality factor of 0.86 for the Tiger Ausf B's turret. The firing test against the Tiger B turret front, however, was conducted after removal of the gun and mantlet, and resulted in penetrations close to armour openings, such as vision slits and gun location. The penetrations to the right gun opening were influenced by previous 100 mm projectile penetration hits or armour damage. The tank's hull and turret side plates were penetrated by АР shot from domestic 85 mm and American 76 mm guns at ranges of 800–2,000 m (2,600–6,600 ft). The 100 mm BS-3 and 122 mm A-19 could also penetrate the weld joints of the front hull at ranges of 500–600 metres after 3–4 shots.

Despite the wartime testing, there is no reliable evidence that the front armour of the King Tiger had ever been penetrated in combat.

Surviving vehicles

The only working example is displayed at the Musée des Blindés, Saumur, France. It has the production turret and is accessible to the public. Other survivors include: