Study of the enemy’s new weapons or vehicles is always one of the army’s highest priority objectives. The appearance of the Panther tank on the battlefields of WWII could not have gone unnoticed without the Allies’ knowledge, and the British were no exception. Information on this new tank was gathered in several stages.
Foreign sources
Rumours about a new German tank began to arrive in the UK in the summer of 1943. The British military attache in the USSR sent a translation of an article published in the Red Star newspaper on July 24th, 1943, describing the use of a new German tank called “Panterra”. There was little information on this tank, plus the author continuously mixed up the Panther and Ferdinand. More accurate information only arrived on September 7th. With hindsight, we can see that the 45 ton “German Heavy Tank, Mark V” armed with a 75 mm gun and equipped with eight interleaved road wheels per side is indeed the Panther.
These same characteristics were later published in the American Tactical & Technical Trends magazine, with one important distinction: the tank was now called a medium tank, a halfway point between the 22 ton Panzer IV and 57 ton Tiger. Despite the weight difference, the Americans considered this 45 ton tank to be an analogue of their own Sherman, which according to American sources was highly regarded by the Germans.
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| One of the first images of the Panther tank widely distributed among the Allies |
This new Panther tank allegedly reached the speed of 50 kph (31 mph) with its 640 hp engine, which indeed equalled it with the Sherman in terms of mobility. The armour and armament surpassed the Sherman considerably: the turret front and gun mantlet were 100 mm thick, the upper front plate was 85 mm thick and installed at an angle of 57 degrees from vertical, the lower front plate was 75 mm thick and placed at 53 degrees from vertical. The Americans decided that the 75 mm gun with a 5.5 meter long barrel must have been a variant of the 7.5 cm Pak 41 gun with a tapered bore. According to intelligence, this gun penetrated 112 mm of armour at 500 meters with a muzzle velocity of 1220 m/s, but the barrel lifespan was low, just 500-600 shots.
The Soviet article suggested hitting this tank from the sides. The turret side could be penetrated with a 54 mm gun (it’s unclear whether the author meant a 57 or 45 mm gun) from a range of up to 800 meters, and the sides of the hull could be penetrated with a 45 mm gun. Large caliber HE shells were also effective. The tank could also be knocked out with anti-tank mines or Molotov Cocktails and anti-tank grenades.
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| Early intelligence on the Panther’s armour protection. Later trials showed that this estimate was overly pessimistic. |
More information became available in the spring of 1944. By May, it was known that the gun was called 7.5 cm KwK 42 and had a muzzle velocity of 935 m/s. It could penetrate 110 mm of armour at 30 degrees at a range of 1000 yards. The armour thicknesses were also corrected: the turret front was 110 mm thick, the upper front plate 80 mm, the lower front plate 60 mm. Due to its sharp angle, American specialists estimated its effectiveness to be 121 and 91 mm respectively. The armour of this new tank was even more impressive than that of the Tiger. Preliminary information suggested that it was only vulnerable to the 17-pounder gun from the front, and even then only when firing at the turret.
The sides were not as tough: the superstructure sides were only 40 mm thick (45 mm effective due to sloping) and the lower part was 40 mm thick and vertical. This armour could be penetrated with any anti-tank weapon.
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| A Panther Ausf.D received from the USSR, three quarters view. |
The British did not have to work off rumours and hearsay for long. A Panther tank with serial number #213101 arrived from the USSR by the summer of 1944. This tank was gently used, having already traveled for 500 miles (800 km). Trials began on June 12th. Churchill VII, Sherman II, and Cromwell tanks were also used in the trials as a comparison.
The Panther could successfully drive up a gravel covered 22.5° slope and a concrete plate at 24°. Other tanks involved in comparative trials could also stop and start on these slopes, but due to the poor condition of the Panther’s hydraulics the testers decided not to do this. The hydraulic system sprung a leak when driving up Beacon Hill and had to constantly be topped up. The average ascent speed was 8.19 mph (13.2 kph), about the same as the Churchill, but worse than the Sherman (10.4 mph or 16.7 kph) or Cromwell (20.6 mph or 33 kph). A 40° grass slope proved too much for the Panther; the engine started misfiring and caught fire. The fire was quickly put out.
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| The same tank seen from the right side. |
Trials of the suspension also did not go off without a hitch. The bump stops for the seventh wheel on both sides came off during the cross-country course. The tank also dipped significantly when crossing large bumps, which was quite unpleasant for the crew.
The Panther was then sent to fuel economy trials, but they could not be finished. The tank could not remain in third gear due to slippage. The engine started giving trouble two laps in. The trials were cancelled and the Panther returned to repairs. One overhaul later, the tank returned to trials on June 28th. The third gear was still defective and thus not used. Things were going smoothly at first, but not for long. The tank developed engine trouble after one lap (giving a worse speed than even the Churchill, 9.5 mph or 15.3 kph vs 10.2 mph or 16.4 kph). The steering had to be adjusted one half-lap later, and the tank was temporarily taken out of trials for maintenance. The engine backfired after being switched off, which caused a considerable explosion in the engine compartment. The tank burned out completely this time and nothing else could be done.
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| The Panther tank on trials at the Fighting Vehicle Proving Establishment. Trials showed that this tank was extremely unreliable. |
The behaviour of the Panther tank did not impress the British commission. The tank was unreliable and needed repairs so frequently that it was carted around the proving grounds on a tank transporter to avoid running it needlessly. According to the British, the engine components were “of a sub-standard or obsolete type”, not a surprising conclusion considering that the tank performed worse than a Churchill VII with 3232 miles under its belt, more than 6 times as much as the Panther had driven. The suspension design was also deemed poor. It’s not surprising that the British testers judged the Panther’s reliability to be much worse than “any British tank now in the service”.
Lair of the beast
Luckily for British proving grounds staff, the army no longer had to rely on foreign sources to obtain Panther tanks. The Panther turned out to be a common sight in France, and getting intact specimens back to Shoeburyness was not difficult. Having already established the mobility limitations of the Panther tank, the British decided to evaluate another key aspect of this vehicle: its armour. These trials were held in October-November of 1944.
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| The Panther tank before trials. |
Firing at slits with 0.303 rifle rounds resulted in little effect. Splash could penetrate inside the tank, but not with enough energy to disable the crew. The most effective place to shoot at was the rear hatch, as it did not close properly. The testers assumed that the lock was bent.
Splinters from the 25-pounder gun proved more effective. At a simulated range of 5000 yards four out of five shots struck the tank’s radiators with splinters. The degree of damage was so severe that any one would have disabled the tank in battle. It was also possible to damage the radiators using a 20 mm aircraft autocannon firing at 27° from horizontal.
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| Damage dealt to the engine deck with 25-pounder HE shell splinters and 20 mm autocannon fire. |
The 57 mm 6-pounder gun could defeat the tank’s armour from the front only by ricocheting APCBC shot from the bottom of the gun mantlet. This resulted in the penetration of the driver’s compartment roof and would have led to an ammunition fire if the tank was fully stowed. Testers estimated that this kind of trick could be pulled off from 1270-1780 yards (1160-1630 meters). The 6-pounder could also penetrate the side of the turret from an angle as large as 50°. At this angle the superstructure side could also be penetrated at a range of 1020 yards (930 m), and even nonpenetrating shots caused cracks.
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| Results of firing the 6-pounder gun at the mantlet. Round #5 scooped downwards and penetrated the driver’s compartment roof. |
APDS shot could not penetrate the gun mantlet, but two hits jammed the turret so hard that they had to be cut out with a torch. This shot could also penetrate the side of the turret from 2500 yards (2290 meters) at an angle of 50° or from 700 yards (640 m) at an angle of 60°. This was the same range at which the lower front plate could be penetrated.
The 76 mm 17-pounder could penetrate the upper front plate from 1500 yards (1370 m) with APDS shot, but even regular APCBC could defeat the tank from 800 meters. The first shot resulted in a crack, the second knocked out a large chunk. An AP shot penetrated the upper front plate from 900-1000 yards (820-910 m) causing new cracks. The front of the hull was now in such poor condition that it was no longer fired upon.
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| The 17-pounder knocked out a large chunk from the upper glacis of the tank. |
Trials using the American 75 mm M61 shell were even more impressive:
“One round of American M.61 A.P.C.B.C. was directed at the lower half of the turret mantlet at the near side. The round detonated, scooped downward, shattered the roof plate behind the driver’s hatch, and passed into the hull with large pieces of the roof plate. Considerable internal damage was caused, and it is probable that severe injury would have incapacitated the driver even if a cordite fire did not occur in the damaged bin behind his back.”
75 mm HE shells could also shatter the roof of the turret if they hit close to the top of the side armour. One shell was fired at the rear turret hatch, and even though it was not torn off or jammed shell splinters damaged the radiators. A hit to the hull resulted in a crack, but no other damage.
A direct hit with 25-pounder HE managed to jam the hatch and damage the radiators. One shell that hit the turret side deformed the roof, another hit the side and made a 7 foot long crack and 2 inch wide breach.
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| Significant cracking of the side armour as a result of being hit with 6-pounder shot. |
The tank’s tracks turned out to be a tough nut to crack. A Mk.V H.C. anti-tank mine was needed to tear them, or three No.75 grenades.
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| Damage to the front road wheel and track as a result of detonating a Mk.V H.C. mine. |
The trials were later partially repeated by shooting up a turret from a Panther Ausf.G. The results were the same: APBCB and AP shells and shot resulted in cracks and spalling. The quality of German armour was much lower than that of the British.
The commission concluded that the tank burns easily as a result of hits to ammunition racks and fuel tanks. The quality of the Panther’s armour was unsatisfactory, same as with the tank received from the USSR. Study of Panther tanks on the battlefield showed that this problem was not unique to the tanks studied at the proving grounds. In many cases the weld seams were already cracked, and the presence of the Zimmerit coating served to mask these defects.
Post-war trials
The British did not abandon the Panther after the end of the war. Five vehicles were obtained to perform wide scale trials: two ordinary tanks, two Jagdpanther tank destroyers, and one Bergepanther ARV. The Bergepanther was supplied with a new engine (it needed one despite only having driven for 632 km) and the rest of the tanks were brand new, having been assembled at British Army of the Rhine (BAOR) workshops. Alas, even with five vehicles the testers could not complete their tests fully.
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| One of the BAOR-built Panthers at the Bovington Tank Museum. |
What little data was obtained was not kind to the German vehicle. Like the Soviet trophy, their engines self-ignited (multiple times on each tank) and broke down often. This time tests established that the turning mechanism was quite unreliable. It was so dangerous to turn at a high speed that fuel economy trials were never conducted. The seventh gear proved practically inaccessible, it could only be used in optimal conditions, on flat and smooth paved roads. Even in this gear the tanks would not accelerate to their claimed top speed.
The brakes were too weak to hold the tank on a 22° slope. One tank slipped off such a slope and the driver lost control of his tank, hitting a tree stump. The impact broke a torsion bar, which in turn punctured the gearbox. This was the last tank, as the others were cannibalized for parts to keep the trials going. As there was nothing left to test, the trials were closed.
Finally, the British decided to check how comfortable the tank was for its crews. These trials were also carried out in a tank assembled by the BAOR.
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| The same tank from the rear. Despite having four brand new vehicles and a refurbished one, the British could not complete trials of the Panther. |
The commander’s station was comfortable, but not without drawbacks. For instance, if he stood up to look out of the turret during movement his feet could easily slip. The rubber padding on the episcopes was too rigid and did not protect his face from impacts. The commander’s seat could not be adjusted.
The only element of the gunner’s station that was comfortable to use was the seat, although it was nearly impossible to work while sitting in. The turret traverse flywheel handle was deemed too short at 3 inches. The turret could also be traversed using pedals, but they were very badly placed. The gunner had to twist his whole body to the right in order to use them. The traverse pedals were also very stiff, and using them was difficult. The elevation flywheel was also quite stiff, as a result of which aiming the gun took a very long time. The gunner had no vision facilities aside from the TZF 12a sight, and so it could take up to 30 seconds to put the gun on target. It was also impossible to use the headphones and gun sight at the same time, as the right headphone fouled the side of the turret.
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| Breech of the 75 mm KwK 42 cannon. This was a powerful gun, but it was difficult to aim and load due to the design of the Panther tank. |
The loader’s station was only 5’3” high (about 160 cm), meaning that an average man would have to work hunched over, which tired him quickly. The loader had neither a seat nor headphones, so the commander could not give him orders. This was strange, as it was the loader’s job to not just load the gun, but also fire the smoke grenade launchers located on both sides of the turret. The ammunition racks were poorly designed. Effort from both hands was required to open the latches holding the rounds. It took about 10 second to open the latches, which reduced the rate of fire. Loading from the ready rack took 6 seconds on average.
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| The radio operator had to lean his entire body to the left in order to fire the hull machine gun. |
The driver’s station was cramped. The seat could be moved from travel to fighting position along the vertical axis, but the British determined that this took too much time and preferred the mechanism on the American Pershing tank. The driver’s visibility was very poor in the lower position, as he could only look through one periscope.
The radio operator’s station was also very cramped, especially around the knees. Using the machine gun was uncomfortable as his whole body had to lean to the left.
The results of British testing revealed many weaknesses of the captured German "big cats". The Panther had many advantages on the battlefield over lighter tanks, but these advantages were mitigated by a number of seemingly secondary factors. The powerful gun was hard to load and aim, the thick armour was of poor quality and spalled easily, and the unreliable engine and transmission meant that the tank could not be expected to arrive where it was needed. It is not surprising that even the British, who largely lost their lead in tank building, thought so poorly of this vehicle.
Sources
- The Chieftain's Hatch: Tigers and Panterras
- Tactical & Technical Trends №37
- Tactical & Technical Trends №40
- Fighting Vehicles proving Establishment Field Trials Report on German Panther (Pz.Kw.V) F.V.P.E. Report No.F.T.1391
- Armour Branch Report on Comprehensive Firing Trials against German Panther Pz.Kw. V.
- Fighting Vehicles Proving Establishment Automotive Wing Report On Panther – Performance Trials
- Military Operational Research Report No 61 Study No.11 issued by Motion Study Wing, Motion Studies of German Tanks