Monday, 20 February 2023

Tiger, Tiger, Burning Bright

The British first encountered the Tiger tank on the battlefield towards the end of 1942 in Tunisia. Employment of Tigers in early 1943 resulted in a number of losses. The Germans were fairly diligent about demolishing tanks that could not be recovered, but an intact sample was found for study before too long. This vehicle and many others were studied thoroughly by British experts in order to build a complete picture of the first German heavy tank.

Man on the inside

As with the Panther, the captured Tiger tank was used for crew comfort trials. Preliminary information about crew comfort obtained during brief inspection in Tunisia was confirmed.

The commander’s workspace was tested first. The massive gun breech made his station quite cramped. From the right the recoil guard constrained his movements in every position, from the left his space was limited by either the turret traverse mechanism (in the lower and standing positions) or the turret wall (in the upper position). His seat lacked a back, and shocks during travel threw him against the hard gas mask rack. The commander had an auxiliary turret traverse flywheel, but it was poorly positioned and he had to twist his wrist to use it. His wrist also chafed against the turret travel lock as the flywheel turned. British specialists described the commander’s position as “cramped and uncomfortable”.

Tiger 131 at the start of crew comfort trials. Narrow transport tracks are installed. The British captured a full set of both transport and combat tracks.

The commander’s cupola was found lacking, and warranted separate criticism. According to British testers, it appeared that the designers did not consider near vision to be important. The commander’s cupola was placed off-center, unlike on the Pz.Kpfw.III and Pz.Kpfw.IV tanks, giving poor vision to the right and right-rear. Looking backwards was particularly difficult, as it was hard for the commander to turn around in his cramped workspace. The vision blocks theoretically gave the commander full 360 degrees of vision, but it was impossible to see one block’s entire range at once. The narrow fixed apertures meant that the commander had to move his head in relation to the vision block in order to get a full field of view. Head movement was also required to see the entire vertical range.

The commander’s station. The flywheel allowed the commander to traverse the turret himself. In practice, it was very difficult to use.

The gunner’s station was also cramped. He had to pull up his knees in order to sit down. It was impossible to use the aiming flywheels or gun sight without leaning forward, which made his position even less comfortable. The testers didn’t like the sight. Its rubber padding was too hard to protect the gunner’s forehead and the location made it difficult to use while wearing headphones.

Vision diagram of the commander’s cupola, showing blind spots. The commander had great difficulty seeing to the right and behind him.

The elevation flywheel handle was too small to grip properly. The traverse flywheel wasn’t much better. If the gunner used his right hand to turn it then he risked cutting himself on the clinometer, if he used his left hand then the wrist would chafe against the turret ring. Either way, he would have to turn it a lot, as it took two full rotations to turn the turret just one degree. The British described this process as “slow and tedious”. The commander could turn his flywheel to help, but then the gunner’s flywheel would begin to spin with such speed that it was impossible to hold on to. As the flywheel slipped out of the gunner’s hand, he released the safety, which locked both his flywheel and the commander’s.

Other crewmen could make up for shortfalls in the commander’s vision, but with the exception of the driver their observation devices were difficult to use.

Powered traverse was activated with pedals, but it was not simple to use. The pedals were placed poorly and the gunner tired quickly when using them. They often jammed and the turret would continue turning even after the gunner released the pedal. It was also easy to press the pedals by accident, for instance when firing the coaxial machine gun (which was also triggered with a pedal). It was impossible to quickly and precisely turn the turret using the pedal controls. British testers deemed the gunner’s position to be the least comfortable out of all the Tiger's crewmen.

The gunner’s vision facilities were also limited. In addition to his gun sight he could also look to the left through the vision port on the side of the turret. Much like the commander’s vision blocks, significant head movement was required to get the full range of view.

Gunner’s station with T.Z.F.9 (b) gun sight. This position was the least comfortable one in the tank.

The loader’s position seemed more comfortable. His seat was good and could fold under the gun so he could work while standing. However, reloading the main gun was difficult. The machine gun was also hard to load, as it was located too close to the main gun. Due to a lack of lighting the loader couldn’t see the ammunition in racks if it was a cloudy day. It was also easy to injure one’s fingers on the ammunition racks. Each British tester was “bitten” several times while loading.

The loader’s side of the turret, front part. The loader could not make full use of the vision block due to the stowage box in front of it.

The balancing springs of the loader’s hatch ate up space in the already low fighting compartment, so the loader had to hunch down while he was working. He also had to expose his whole body if he wanted to close the hatch. The British tried to use the evacuation hatch in the side of the turret to throw out shell casings, but it was not suited for the purpose. It was too heavy for one man to close from inside the turret, and leaving it open impeded traverse of the turret.

Ammunition stowage in pannier racks. The ammunition was badly balanced, which made handling it difficult.

It took 7-8 seconds to load the gun from the ready racks. As ammunition was expended, it could take up to 24 seconds to retrieve a shell, as the loader’s access to other racks was blocked with various items including his own seat. It took 2.4 seconds to extract a spent casing after the gun fired. The British deemed the process of loading the gun to be “excessively long”.

The loader had a vision block in the side of the turret like the gunner did, but the location of stowage next to it prevented him from using the full range of view, as he could not position his head at a proper angle. The loader’s position was described as “uncomfortably blind”.

The loader’s side of the turret, rear part, showing the evacuation hatch. This hatch was unsuitable for discarding spent shell casings.

Compared to the turret crew, the hull crew worked in relative comfort. The British complained that the driver lacked legroom and that his seat could not be locked in a travel position to look out of his hatch while driving. Regardless, the driver was the only one to be described as having “good and adequate vision” thanks to his vision port in the front of the hull.

The driver’s station. According to British testers, this was the only crewman with adequate vision.

The radio operator/machine gunner had more legroom than the gunner did, although his seat was less comfortable. However, his machine gun was very difficult to use (the report author even underlined the word “very”). It was poorly balanced, and even the balancing spring didn’t help much. The British also questioned why the radio operator’s periscope was placed at an angle instead of looking straight ahead.

Both the driver and radio operator had fixed vision periscopes in their stations, but since the prisms were out of order their range of view could not be mapped.

Tiger in action

The gun was perhaps one of the most interesting features of the tank, and thus tested very thoroughly. Stripping the breech mechanism was deemed very easy. All moving parts could be removed without the use of tools.

Internals of the Tiger’s fighting compartment.

Gunnery trials showed that the accuracy of the gun was excellent. At 1200 yards (1097 m) a grouping of five shots fell into a 16” by 18” (41 by 46 cm rectangle). The tank also scored a hit on a moving target from 1500 yards (1371 m). A target at 1800 yards (1645 m) was hit on the fourth shot with the use of a clinometer. Although the gunner couldn’t see the target due to smoke, the commander could walk him onto it. The commander could also use his auxiliary traverse flywheel to aim the tank at targets the gunner couldn’t see through his gun sight, at least in theory. This was a useful feature, since the gun produced a large cloud of smoke when fired and it was impossible for the gunner to observe strikes at ranges less than 1600 yards (1463 m) due to how long it took for the smoke to clear. The commander could observe over the top of the smoke cloud using a binocular periscope. The testers noted that this method was similar to that used in British tanks, except the German binoculars had inferior light transmission to British ones. Another drawback of the gun was the large flash and flashback that occurred during firing. The normal rate of fire was measured to be 5-8 RPM, with the maximum attained rate of fire being 4 rounds in 39 seconds (timing started with one round already loaded). Ammunition was described as unbalanced, being projectile heavy, which made it harder to handle and reduced the rate of fire. With the engine off and ventilation fan running, the concentration of CO in the fighting compartment was dangerously high.

Recoil length was found to be 520 mm when firing HE and 530 mm when firing APCBC on average, up to 580 mm. The recoil mechanisms worked well, testers remarked that the gun recoils and returns smoothly. The light electric trigger was also praised.

Stability of the tank when firing was good, with the exception of the gun rising after firing for the first 2-3 shots after the tank changed positions. According to the testers, this was likely caused by the suspension settling.

The Tiger tank was a popular attraction for VIPs. Whitehall, London, 1944.

The mobility of the tank was also put to the test. Mobility trials in soft soil were undertaken in December 1944. After driving only 30 yards through churned up loam, sand, and clay soaked by thawing frost, the tank’s nose dipped downwards and it became stuck. The Tiger could not move either backwards or forwards under its own power and had to be pulled out. This was by far the worst performance of all vehicles involved in the trial, even worse than a stock Sherman without extended end connectors. The Tiger fared little better in the second set of trials. In slope climbing trials the tank started slipping on the moist clay at an angle of only 13 degrees, again showing the worst performance of all vehicles tested. As a result of these trials, the Tiger’s mobility in mud was described only as “very poor”. This is not a surprising performance, as according to post-war inspections of German documents, Henschel had no formal soft soil mobility programme and advised the users of its tanks to simply avoid mud.

Cutaway drawing of the Tiger tank.

Further trials showed that the Tiger didn’t excel in dry conditions either. The air filter, tested separately from the tank itself, proved to be “considerably below the requirement of this Department [of Tank Design]” in both de-dusting efficiency and dust capacity. The poor filtration was only a portion of the problem. According to captured German documents, they were no strangers to problems with air cleaners, as they had considerable trouble maintaining an airtight joint between the cleaner’s air outlet and the engine.

Top speed in ordinary conditions was found to be 18 mph (29 kph).

Tiger’s thick skin

Since the British only had one intact Tiger tank, they were not keen on performing penetration trials, especially since there was already data available from trials performed in North Africa. Development of new anti-tank weapons required another set of trials, and so in March of 1945 a Tiger tank captured in Normandy was shot up at Shoeburyness. This tank was not in ideal condition: it was missing the driver’s vision device, turret observation devices and commander’s cupola periscopes, a pistol port plug, and one road wheel. Nevertheless, its armour was intact and ready for testing.

The Tiger tank chosen for penetration trials.

Attempts to jam the machine gun ball mount with .303 rifle fire proved fruitless. Only a little splash made it through and the machine gun remained operable, although AP bullets successfully jammed the ball mount. The first time it was loosened by hand, but the second time the machine gun was effectively put out of action. The driver’s visor proved an easier target. Splash from ordinary bullets made it through the closed visor, and AP bullets could jam it as well.

Armour thickness of the Tiger tank.

Bullets could not damage or jam the turret ring. The commander’s cupola hatch also proved resistant to rifle bullets, although the bullets successfully penetrated the rubber liner on the driver’s hatch, the slit between the gun mantlet and the turret, and gaps around the turret evacuation hatch. All of these hits could wound the crew inside the tank. When firing at a 30 degree angle, rifle fire could also hit the radiator through the engine deck. Splinters from a 25-pounder shell damaged the radiator to such a degree that the loss of water would lead to the tank overheating within five minutes. A second shot gave the same results.

 Location of 25-pounder shell bursts that penetrated the radiator.

20 mm AP shells imitating a ground attack aircraft also dealt fatal damage to the radiator as well as destroying the cooling fan. One shell pierced the fuel tank, although the gas did not ignite. AP-I shells could have set the tank on fire, although incendiary shells fired in this test did not hit the fuel tank. These types of shells also penetrated the engine deck and destroyed the radiator.

Firing at the front of the hull with 6-pounder APDS showed that penetration could be expected from about 1000 yards (914 m). The spare track links effectively worked as spaced armour, and APDS would only have penetrated the hull behind them at point-blank range. The same effect was observed with turret armour: the side of the turret could be penetrated at 40 degrees from a range of 1200 meters, but when firing through a Panther track link penetration could only be obtained at close range. A hit within 2.5” (63.5 mm) of the observation slit destroyed the welding seam. It would have knocked out the observation device, if it was present. Firing at the gun mantlet at an angle of 30 degrees showed that penetration could be expected at a range of 1200 yards (1097 meters).

British test team putting out a fire that broke out after the tank was hit with a 6-pounder shot.

6-pounder APCBC shot fired at a speed of 2595 fps (equivalent to a range of about 300 yards or 274 meters) penetrated the side of the turret at an angle of 20 degrees and destroyed the gun’s recoil brake. Another shot hit close to the roof and tore a chuck off it. At the same angle, a shell with a velocity of 2575 fps penetrated the hull side. Another shot with a velocity of 2534 fps penetrated the lower hull and started a fire. The report author doubted if such a should could be successful if all road wheels were in place.

One shot hit the lower part of the gun mantlet at a speed of 2398 fps (just under 1000 yards or 914 m), ricocheted downwards, knocked a 7.5” by 4” (190 by 100 mm) chunk out of the roof, destroyed the gearbox and smashed the mannequin representing the driver. It’s likely that other crewmen would also have been killed or wounded by such damage.

Severe damage to the ammunition rack as a result of a shot to the side. This damage would have destroyed the tank if live ammunition was present.

17-pounder APDS shot managed to penetrate the side of the turret at an angle of 40 degrees from 1300 yards (1189 m). This armour was also penetrated at longer distances and at a higher angle (50 degrees). At 41 degrees APDS shot could penetrate the driver’s visor at 800 yards (732 meters). Penetration of the gun mantlet was likely at 40 degrees at a range of up to 1500 yards (1372 m).

AP shot penetrated the side armour at a velocity of 2900 fps (point blank range). At 2983 fps the armour was not penetrated, but the welding seams holding the plate burst. Hitting the front plate guaranteed a penetration. Shots impacting at velocities as low as 1923 fps (2000 yards or 1828 meters) resulted in cracking seams, torn out chunks of armour, and would likely have put both the tank and crew out of action. The armour was difficult to penetrate at an angle of 50 degrees, but a hit close to the roof resulted in a chunk torn out from it. The location of the hit meant that ammunition stored in the pannier would have detonated. Unlike the smaller 6-pounder shot, 17-pounder ammunition freely penetrated the tracks and wheels, successfully destroying the running gear and final drives.

The pannier floor was blown out by a 75 mm HE shell. If the tank was filled with real ammunition, it would have burned up.

A 75 mm M61 shell fired from the Sherman’s 75 mm gun did not penetrate the upper side armour, but it penetrated the lower hull and knocked out a large chunk of armour, which would have killed the driver and radio operator. An HE shell that hit the gun mantlet widened existing cracks in the roof and caused a new one. Another HE shell that hit under the pannier caused a greater effect: the pannier floor was knocked out and the tracks were destroyed. If any ammunition was carried on board, it would have detonated and the tank would be destroyed.

The PIAT anti-tank grenade launcher could penetrate the side of the hull and turret at 30 degrees, but could not penetrate the hull behind two road wheels. The 102 mm thick front was also penetrated. The hit would have killed the driver and destroyed the final drive.

The Tiger’s track was a tough nut to crack. Just one mine or anti-tank grenade would not be enough. Only a pair of mines that exploded underneath the center of the track could destroy it.

Result of detonation of 15 Hawkins grenades under the tank. Road wheels, ## 5, 6, and 7 were torn off by the explosion, with wheel #7 displaced to a considerable distance.

Metallurgical analysis showed that the armour was softer than expected. The report author theorized that this was done in order to reduce the amount of cracking and spalling. As with the Panther, the tank had numerous small cracks around the welding seams that were covered up with Zimmerit. The layer of Zimmerit was 3/16th of an inch thick (4.67 mm). Trials showed that it was equivalent in function to British anti-magnetic coatings. It chipped away easily when bullets hit the hull and an HE shell could clear a large section.

These trials showed that while the Tiger was an impressive fighting machine, it was not without weaknesses. Close inspection revealed issues with the fighting compartment that limited the effectiveness of its high velocity 88 mm gun, and penetration trials showed that the armour was not only vulnerable to new anti-tank weapons, but also those already in the field when the Tiger first saw battle. Trials held at the end of the war in Europe showed that front line troops already knew: the German heavy tank was far from indestructible.

  • Armour Branch Report on Firing Trial against German Tiger Pz.Kw.VI. Military Operational Research Report No.61 Study No.11 Motion Studies of German Tanks.
  • Tactical & Technical Trends №№ 18, 20, 24, 30, 34.
  • FVPE Report No. F.T.1553 Comparative Trials of Various AFVs in Soft Ground Conditions
  • Canadian Military Headquarters, London (1939–1947) RG 24 C 2;

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