Friday, 25 August 2017

Necessary Improvisations

The American movie Fury, which came out in 2014, was memorable, in part, due to the unusual exterior of the tank, which effectively became one of the main characters. Even though Fury's equipment was, at best, "based on a true story", and the M4A2E8 never fought with the American army, the creators of the movie managed to capture the overall idea of field improvisations. These modifications of American tanks in Europe were a widespread phenomenon, and came about out of necessity.

Falling behind

The first modifications to improve protection of the Medium Tank M4 were made in Italy, in the fall of 1943. It's hard to call them extensive; additional track links were attached to the front of the hull, serving as extra armour. Most likely, the Americans got the idea from German tankers. The idea of using spare track links to protect the front hull was not without merit. As trials performed in the spring of 1944 at the NIBT proving grounds showed, track links lowered the range at which a T-34 could be knocked out by a 7.5 cm KwK 40 from 1000 to 800 meters. This distance often made a difference in war. However, American T41 and T51 rubber-metallic tracks were poorly suited for this purpose.

Typical American tanks in Normandy: light M5A1 and medium M4 tanks. These tanks were good, but a little lacking for the summer of 1944. 

The landings in Normandy on June 6th, 1944, were followed by a boom of improvisations. The first alarm bell for the American tank industry sounded in early 1943, when the Americans first encountered Tiger tanks. By then, the Americans had GMC M10 tank destroyers with 76 mm guns, which could penetrate German heavy tanks. 

American tank designers reacted quickly to the appearance of heavy German tanks: the Medium Tank T20 with a 76 mm gun began trials in May of 1943. The issue was that work on the T20 and T23 medium tanks was running late, and then ran into a dead end. The only result of this project was the T23 turret, which was installed on the M4 chassis. The first such "hybrid" was the M4A1(76)W, put into production in January of 1944. These were the best tanks the Americans had in Normandy. However, the Germans weren't sitting still.

M4A3E8, the best out of all American mass produced tanks in WWII. These are the tanks that the Americans ended the war with.

Tigers usually act as the main enemies of American tanks in movies. In reality, the first heavy tanks (already knocked out) were encountered in August of 1944. There were only two heavy tank battalions in northern France, and they chiefly fought the British, the Canadians, and the Poles.

For the Americans, the scariest enemy was the Panther, which the German had in large amounts. The American 76 mm gun could confidently penetrate the Panther only through the gun mantlet, while the Panther could penetrate American tanks from a far greater range.

American tankers paid dearly for the slipping of their tank development program. A comparison of American and Soviet tank aces illustrates the situation. The Red Army had 4 aces that fought only in T-34-85s that scored 20 or more kills. The highest scoring American tank ace is Lafayette Pool, with 12 kills. The second highest is Creighton Abrams, with six. On VE Day, Abrams was on his seventh tank, and that's after less than a year of fighting!

The Americans had terrifying losses in materiel. Few vehicles that landed in Normandy survived until May of 1945. Of course, bragging of German tank aces about fleeing American tankers should be taken with a grain of salt. The Americans knew how the fight. The issue was that, due to the situation with the American tank industry and ambitions of some commanders, they had to do it on obsolete tanks. It's nor surprising that the tankers had to improvise to stay alive.

Battle with the Green Hell

The Americans fought not only with tanks in Normandy, but also with German anti-tank artillery. Infantry armed with RPzB. 54 (Panzerschreck) rocket launchers was also a serious opponent. The length of time the Americans spent fighting in a relatively small space can be explained by the terrain. Normandy is a hilly region with lots of fields, split up into many sections. The borders between these sections were a massive headache for tankers. Fields were separated by dirt mounds with a hedge planted along them: bocage. A bocage is 1-2 meters tall and seriously impedes visibility. With time, the growing trees and shrubs turn the mound into a formidable wall that even a tank might not be able to cross without special equipment.

Sgt. Curtis Cullen, the inventor of an anti-bocage device.

The Germans, who spent many years building up defenses in Normandy, were perfectly aware of the bocage's defensive qualities, and used them well. American forces took heavy losses from tank destroyers hiding in the bocage. It was necessary to invent a measure against these obstacles in order to demolish them in dangerous places. Bulldozers were poorly suited for this task, since they they too vulnerable.

The first variant of the "rhino". Overall, there were three versions of these rams for light tanks.

The issue was solved in mid-July of 1944. Sgt. Curtis Cullen, a driver of a Light Tank M5A1 from the 102st Cavalry Reconnaissance Squadron, suggested an idea. Recalling his own experience in demolishing hedges, he designed a tool built out of German anti-tank hedgehogs. Blades were welded to a large beam, and the beam was welded to the lower hull. The tank dug into the bocage with the blades, and then tore it with its mass. A tank without Cullen's device simply rode up it without dealing any noticeable damage.

Cutting apart anti-tank hedgehogs. They were often used to build "rhinos". 

A demonstration to General Bradley, the commander of the 1st Army, held in mid-July, was successful. A tank equipped with the device demolished a bocage on the first try. 500 sets of these rams were ordered immediately. They were built out of anti-tank hedgehogs and steel obstacles that littered the beaches. By the start of Operation Cobra, which penetrated the German defenses around the Normandy foothold and broke through to operational freedom in north-western France, field workshops managed to make a large amount of them. A means of demolishing bocages made a significant impact on the success of the operation.

One of the most common kinds of ram for medium tanks.

Cullen's invention quickly gained several variants. M4 tanks used both the light tank type and a new design. Instead of four or five blades, there were only three, but the outer ones were much larger. They allowed the tank to dig into the bocage more effectively. There was also a version for M10 tank destroyers, with a different shape for the blades. Since the rams were made in field conditions and from various materials, their shapes could vary.

The rams were also installed on M7 SPGs. This photo was taken in early 1945.

After fighting in Normandy was over, there was no longer a need for "rhinos". Nevertheless, tanks and SPGs equipped with Cullen's device still cropped up in the spring of 1945. Sgt. Cullen himself survived the war, although he stepped on a landmine in the fall of 1944 and was left without a leg.

Force of the earth

Improvised armouring of American tanks that also appeared in the summer of 1944 became even more famous than Cullen's device. Later, it became the subject of many jokes, but their users weren't laughing. This improvisation was the use of sandbags to protect the front armour.

The most popular variant of the sandbag armour. The sandbags only protect the front of the hull.

Sandbags were initially attached to tanks in late June of 1944. It is not known who was the first to implement this innovation, but it clearly appeared for a reason. You often hear that American tankers were trying to protect themselves from anti-tank guns, but this opinion is baseless. Even on an M4 tank, the sandbags would work as well as spare track links, at best. In addition, you could see them on light tanks, which could be penetrated by nearly any anti-tank gun, sandbags or no. 

A more "advanced" variant that shielded the sides of the hull and the turret.

Sandbags were meant to protect from a different weapon: handheld rocket launchers. They fired HEAT warheads, and sandbags turned out to be an effective defense against them. The HEAT jet lost some of its force while passing through the sand. It's likely that a crew tried out this protection in battle and stayed alive, news of which spread across the front. As a result, a great deal of tanks, light and medium, were equipped with sandbags by July.

Of course, the tank didn't get any lighter as a result. In addition, tanks had many enemies other than rocket launchers. Nevertheless, this improvisation gained popularity.

The most "packed" variant, an M4A3E8. This is a tank from the 14th Armored Division.

Despite the drawbacks, this modification was not forbidden. Even the improved morale was a bonus. The design of this protection was improved with time.

Protection with logs. The creators of Fury were likely inspired by this image. Pictured is an M4A3(75)W from the 7th Armored Division.

The fact that sandbags were meant to protect from HEAT warheads is highlighted by its further development. By 1945, additional protection was added on the sides, due to the fact that tanks were knocked out from ambushes more and more often. German infantry was also saturated with anti-tank rocket launchers, including single use Panzerfausts. It's not surprising that more effective protection was needed. Around this time, the logs that are so well known from Fury turned up. Tankers discovered experimentally that wood protects from HEAT warheads and weighs less than sandbags. They didn't look as good, but got the job done. 

Cementing the front of an M4A3(105)W from the 2nd Armoured Division.

Sandbags and logs weren't the only types of improvised protection. American tankers got the idea of cementing the front of their tanks from the Germans. This was a common practice on StuG 40 SPGs. The technique was more effective than sandbags, could hold more hits, and stayed on better. However, due to the difficulty of the process, cementing was less common and only encountered towards the end of the war.

Prestidigitation with a welding torch

Sandbags weren't the end of it. By early 1945, work on more radical improvement of armour began in some units. German tank and anti-tank guns could easily penetrate American tanks, and something had to be done. Since the percentage of well armoured T26E3 Pershing tanks was miserly, the tankers fended for themselves. Someone had the bright idea of installing additional armour on existing tanks.

Missing parts of the hull indicate that the tank was a "donor" for applique armour.

There was no shortage of armour in early 1945, just the opposite. In addition to knocked out American tanks, the Germans left many vehicles after a failed counteroffensive in the Ardennes. These were put to good use. Photos from 1945 show tanks with missing side or front hull plates lining the side of the road. These missing pieces were used to unarmour tanks. There were, however, other sources of armour.

An M4A1(76)W from the 3rd Armored Division with atypical applique armour. Instead of several small plates, the tank has a doubled up large plate.

Most commonly, the M4A3E8, the most advanced of the M4 tank family, was the recipient of additional armour. The new HVSS suspension was more suitable for the additional load. 

Usually, only the front part of the hull received applique armour. Additional armour was bolted to the upper front plate and the transmission block. There were also plates that were welded to the hull. The method of attachment depended on the unit doing the job. The thickness of the armour also depended on the donor. If the sides of a Panther were cut up, then the total thickness of the armour could be over 100 mm.

Typical applique armour on an M4A3E8. In this case, the plates are welded on, no bolted.

The most famous variant was designed by the repairmen of the 4th Armored Division. This is largely connected with the fact that Creighton Abrams' M4A3E8 was converted this way. His tank, the Thunderbolt VII, was not unique. Other tanks from the division received this upgrade too. There waw also spaced applique armour on the sides. This was the most advanced type of applique armour.

Thunderbolt VII, Crichton Adams' tank.

It's worth noting that the applique armour was a lot less common than sandbags in the American army. This is because this kind of armour took much more time and complex equipment. Finally, heavy additional armour reduced the tank's mobility.

Applique armour was removed as soon as the war was over, but sandbags and logs made a comeback. These improvisations turned up again during the Korean War for the same reason, to protect against HEAT warheads. Even in our time, techniques first invented during WWII are commonly used in small scale conflicts. As we all know, everything old is new again.

4 comments:

  1. "The Red Army had 4 aces that fought only in T-34-85s that scored 20 or more kills. The highest scoring American tank ace is Lafayette Pool, with 12 kills. The second highest is Creighton Abrams, with six."

    I imagine this has a lot to do with a relative lack of opportunity on the Western Front as well. Tank v tank engagements were a lot rarer than in the East.

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  2. The logs shown on the M4A3 hull sides may not be intended for additional protection, even if they are serving that purpose.

    A standard US Army method for quickly creating improvised corduroy roads was to wire together bundles of relatively small logs. These were carried on tank and halftrack sides as an easier means of transporting them frontward. So at some point, upon striking a patch of soft ground that needed corduroying, the tanks would drop the logs.

    There are lots of photos of M4s from e.g. the 7th Army carrying log bundles on their bows. Same purpose.

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    Replies
    1. Also logs can be use for unsticking tanks. BTDT

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  3. 2 nd note. perhaps the E8 designation/standardization was not around but 76 HVSS M4A2's were, which same thing

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