Appendices

APPENDIX I – Panzers Versus American Armor

The M4 Sherman that we took into Normandy weighed thirty-two tons and had two and a half inches of armor, inclined at forty-five degrees, on its front glacis plate. It had a short-barreled, low-velocity (2,050 feet per second) 75mm gun. Later, about 15 percent of the tanks we received had the new 76mm gun with a higher muzzle velocity (2,650 feet per second).

When the war began in Europe, a confused debate was raging between American tank designers in ordnance and senior officers in the army ground forces. In the summer of 1939, when I was at Aberdeen Proving Ground as an ordnance cadet, our main battle tank was the M2A1 medium tank with a 37mm gun mounted in the turret. After the Germans invaded Poland in September, the debate became more intense. The armored and cavalry officers favored a large-caliber, high-velocity antitank gun mounted in the turret. The infantry officers still thought of the tank as an infantry assault weapon. The artillery officers thought that if a tank was going to carry a gun larger than a 37mm, the gun should conform to artillery specifications, which required a gun to be capable of 7,500 service rounds in combat. To meet this, a 75mm gun and larger would require a relatively low velocity. It apparently never occurred to the artillery officers that few tanks would ever survive in combat long enough to fire 7,500 service rounds. The result of this was the new M3 battle tank, designed by a committee.

This committee chose the new tank’s basic features. It had the M2A1 lower hull and track system, powered by the R975C1 400-horsepower radial engine, and a transmission and final drive similar to that of the old M2A1. The side and frontal armor were increased, and an angular-shaped hull was devised using riveted connections. The front glacis plate, approximately two and a half inches thick, started out at forty-five degrees where it connected with the transmission and extended about halfway up the front. It then had a knuckle riveted joint in the middle and extended upward at about sixty degrees. The riveted joint was used because some officers felt that the welding would weaken the armor plate. This decision was disastrous.

When a small-caliber, armor-piercing bullet struck the head of one of these rivets, it sheared it off and drove the internal part of it into the tank, where it ricocheted like a projectile and killed the crew.

The committee decided to put a 37mm antitank gun in the turret, coaxial with a .30-caliber machine gun. The 37mm was already obsolete and had practically no effect on the frontal armor of German tanks. The turret also had a .50-caliber ring-mount, dual-purpose machine gun. The main armament, conforming to the artillery board’s specifications, was a low-velocity 75mm M2 gun mounted in a barbette enclosure on the right side of the tank. With approximately forty-five degrees of lateral traverse and its low muzzle velocity (2,050 feet per second), it seemed to satisfy the infantry board as a good assault tank.

The tank had a much higher silhouette than any comparable German tank and could be easily spotted from a considerable distance. To make matters worse, the committee was apparently dominated by Yankees, who decided to name this tank the “Grant,” after the Union general and later president. The Southerners were aggravated further by the later naming of the M4, known as the “Sherman,” after the Union general who burned a path through Georgia.

Opposing us were three types of German panzers. The PzKw IV, which we usually called the Mark IV, weighed twenty-three tons and had four inches of vertical armor on the front and a high-velocity (3,000 feet per second) 75mm gun. Next came the PzKw V Panther, weighing fifty-three tons with three and a half inches of armor on the front glacis plate at thirty-eight degrees, below the critical angle of ricochet. The Panther carried a long-barreled, high-velocity (3,300 feet per second) 75mm gun. Finally came the PzKw VI King Tiger, weighing sixty-four tons with six inches of armor at forty-five degrees on the glacis plate and a long-barreled, high-velocity (3,250 feet per second) 88mm gun. The German tanks had a qualitative superiority of as much as five to one over our M4 Sherman.

The combination of superior firepower and heavier armor allowed the German tanks to engage and destroy the M4 Sherman at long range. There were many cases where Shermans would score multiple direct hits on the front of a Panther or a Tiger, only to see the shells bounce off harmlessly. In comparison, the German high-velocity guns could not only penetrate the lighter armor of the Sherman with a single shot at long range, they could knock out a Sherman even after shooting through a brick wall and, in at least one instance, by shooting through another Sherman tank:. Whereas the Sherman had to get within six hundred yards of a Panther and hope to catch it on the flank, the Panther could knock out a Sherman at two thousand yards head-on.

Before the Normandy invasion, some U.S. armored commanders assumed that because the Sherman was lighter than the Panther, it would be more mobile. This assumption was incorrect. The key to a tank’s off-road mobility is its ground bearing pressure: how the weight of the tank is distributed over the ground. Because the Panther had a wider track than the Sherman, it actually had a lower ground bearing pressure and could go places where the Sherman could not. More importantly, the narrow track on the Sherman could not negotiate muddy terrain and snow.

The M4 Sherman’s inferiority was by no means predestined; we enjoyed a great superiority in other weapons systems. After a twenty-year period of isolationism between the wars, in just four years the United States was able to produce superior weapons in vast quantities, including rifles, artillery, motor transports, and aircraft.

As the only officer in the maintenance battalion who had been to the tank maintenance school in Fort Knox, I was knowledgeable about tanks, particularly their technical capabilities. At tank school, I took copious notes and read every field manual I could get my hands on. I also read any G2 ordnance reports we had on German tanks. Unfortunately, this information was limited. I saw no reports on German tanks larger or more powerful than the PzKw III and the PzKw IV with the short-barreled 75mm howitzer. We had no information about the German Panther tank, either, although I had read a newspaper account of the Tiger tanks that were used in North Africa against the 1st Armored Division. Because the M4 Sherman, with the 75mm gun in the turret, was far superior to the old M3, and because our knowledge of comparable German armor was limited, we felt that the M4 was a good tank.

Meanwhile, the Germans were replacing all the short-barreled 75mm guns on their Mark IV tanks with higher velocity guns, and they were developing the Panther and Tiger. The Sherman could not compare with these.

American tank designers also failed to give proper consideration to the latest Soviet advances in armor. Their medium T34 and heavy Josef Stalin tanks were both equipped with more powerful guns, heavier armor, and wider tracks than the M4 Sherman.

The U.S. Army did finally develop the M26 Pershing tank, with heavier armor and wider tracks than the M4, and with a long-barreled 90mm gun. This tank was far superior to the Sherman and would have placed us on a more level playing field with the German armor. However, due to the arrogance of certain high-ranking officers it was recommended that this tank be given a low priority, and production concentrated on the M4

Sherman. Many observers at the time believed that had we had the M26 Pershing during the November 1944 offensive east of Aachen, we might have been able to break through the last vestiges of the Siegfried line, exit onto the Cologne Plain, and outflank the German troops building up in the Ardennes. Had this occurred, the Battle of the Bulge might never have taken place and the war would have ended months earlier.

APPENDIX II – Adding More Protection

I first became aware of the deficiency in the M4 Sherman’s armor in England in November 1943. Major Arlington told me that ordnance had prepared a field service kit to put additional armor plate on all the M4

Sherman tanks, and I was to be in charge of the project. The work was to be performed at Warminster, the main British armored depot. Army ordnance, at Aberdeen, had sent over a technical observer (TO), who was an expert on welding armor. He was on loan from General Motors and had a good background in production welding techniques.

It was my job to work with the British depot commander and secure the necessary labor and facilities. The TO’s job was to work with the British foreman to figure out the necessary jigs and fixtures and welding procedures. After several screwups and near disasters, we finally got things worked out and the job went along smoothly.

From combat experience in North Africa, Sicily, and Italy, we had learned that the M4 Sherman had inadequate armor and was vulnerable in several critical areas. It was felt that the application of this additional armor would overcome some of its vulnerability. The tank carried a combat load of eighty-nine rounds of 75mm ammunition. It was stored with sixteen rounds in each of two racks in the right-hand sponson (the area that overhangs the track) and one rack in the left-hand sponson. There were thirty-two rounds stored in a rack under the turret, in the main fighting compartment, and nine rounds in ready rack clips in the turret itself.

If the tank was penetrated in any of these areas and a fragment penetrated the soft brass case of a 75mm round, the round was likely to detonate and set off the other rounds. A one-inch-thick patch of armor plate approximately eighteen inches by twenty-four inches was welded on the outside of the sponson immediately over the ammunition boxes. Inside the sponsons we fabricated small boxes of quarter-inch armor plate with doors to go around the ammunition, in case a fragment struck the ammunition from the inside. We fabricated another quarter-inch armor plate box with doors to go underneath the turret. On the right forward side of the turret, the cast armor had been thinned out to accommodate the control mechanism for the turret’s hydraulic powered traverse. We welded a two-inch-thick bulbous contoured patch approximately two feet square over this area. On the M4 Shermans with cast armor, the contour of the glacis plate changed radically to an almost perpendicular position right in front of the driver and assistant driver. We welded two large inch-anda-half-thick tapered patches over these areas.

After several days of experimenting, we finally got a good assembly line set up. We were fortunate to have a large fabricated steel shop building with plenty of floor area, overhead cranes, and heat. The building was large enough to accommodate eight tanks at a time. This was unusual for us; we had been used to working in the fields in the rain, sleet, and mud up to our butts.

We would bring the tanks into the long bay and space them about thirty feet apart. Our tank maintenance mechanics got in the tanks and disconnected all the wiring and hydraulic mechanisms from the tank turret.

We removed the bolts from the turret rings, and the crane picked up the entire turret with its attached bottom cage and set it on a fabricated steel stand to one side of the tank.

Three welding crews started tacking the side patches into position, then the regular welders came in and finished the job. Welding armor plate is tricky, but our TO welding expert set up an efficient procedure and trained the British welders in effecting a good weld, using the right kind of alloy rod and making small multiple passes. The heat from each pass tended to stress-relieve the bead underneath to produce a relatively stress-free joint.

One of the first tanks off the assembly line ran over a six-inch timber used for blocking, and this slight jar caused one of the welded patches in front of the driver’s position to crack loose. The British welder had apparently made too large a weld, which built up excessive stress and caused the patch to crack. This condition was corrected, and we proceeded without further incident.

In the meantime, other crews fitted the preassembled ammunition boxes inside the tank sponsons and underneath the turret. Some crews repainted the interior and others repainted the exterior. The turrets were then reinstalled, and the wiring and hydraulic mechanisms were hooked up. Once the production problems were worked out, we were able to turn out eight tanks a day. By working around the clock, we completed the entire division in approximately one month.

Due to my complete ignorance, I got into a hassle with some of the British workmen; it was blown completely out of proportion and almost became an international incident.

Things were hectic during our first few days of operation. One morning, just as things began to settle down, I noticed that at about ten o’clock the lead British foreman signaled the men to stop working. At first I thought this was similar to the incident that happened on board our troop ship at Liverpool, when the stevedores went on a short strike and refused to unload the rest of the ship until a British dock officer got them straightened out.

When I asked the British foreman what was going on, he replied that the men were taking a thirty-minute tea break.

“I’ve got my men working around the clock trying to get these tanks out, and you guys are taking a damn break? Don’t you realize there’s a war going on?”

Here was a young American lieutenant who had just gotten overseas and was telling the British that a war was going on while they had already been in it for four years. Some of these men had had sons at Dunkirk and in North Africa; others had lost members of their family to the bombing.

The tension heightened as I continued to make a fool of myself. I could see that we were getting nowhere, and I walked away to report the work stoppage to the British base commander. The British foreman returned to his men and finished his tea break.

It was finally explained to me that these men worked ten-to twelve-hour shifts. There was insufficient labor in England for war workers to work three shifts, as they did in the United States. The men came to work at seven in the morning and finished at seven in the evening, when the night shift replaced them. The British had five meals a day: breakfast, morning tea, lunch, afternoon tea, and supper. They didn’t eat supper until about eight in the evening. Thus, tea was actually one of their regular meals. Once I understood this, work proceeded smoothly. I never apologized to the British foreman; however, we understood each other, and before the project was finished we became good buddies.

The entire project, involving more than 232 medium tanks, was finished in approximately a month. When we left Warminster, the assembly line was set up for the 2d Armored Division. In addition, several thousand tanks at Tidworth Downs came through the same assembly line that we had established. I recall being at Tidworth Downs when the sixty thousandth tank was unloaded from the transporter. Detroit had painted 60,000 in large numerals about two feet high on the sponson of the M4 Sherman tank. Everyone cheered as the tank was unloaded from the back end of the trailer. I was amazed that this many tanks had been built. The experience of learning how to weld armor plate became an invaluable one later on when we got into combat.

APPENDIX III – Field Deployment of an American Armored Division

During World War II, the U.S. Army had two types of armored divisions. The 1st and the 4th through the 20th Armored Divisions were “light” divisions, each with approximately 11,000 men and 168 medium tanks. The 2d and 3d Armored Divisions were “heavy” divisions, each with approximately 13,500 men and 232 medium tanks. Both types of division had a number of light tanks; because of their extremely limited capability, they were used primarily for reconnaissance. Some felt that the light divisions, based on the highly successful German panzer divisions, would be more effective than the heavy divisions. This was a highly controversial issue among the armored force staff. It was finally decided to leave the 2d and 3d as heavy armored divisions.

The thinking behind the light armored divisions was based on quantitative numbers instead of the qualitative capability. In relative qualitative comparisons of the strength of the main tank forces, the Germans held an edge of at least five to one. Although the light armored divisions did an excellent job, it was soon discovered, after the Normandy invasion, that they did not have the staying power to take horrendous casualties and recover as rapidly as the heavy divisions. As a result, it was decided that in assault operations the 2d and 3d Armored Divisions had to be used to a much greater degree than the lighter units.

Armored Force Tactical Doctrine called for the operation of two types of armored units. The first was the GHQ tank battalion, designed to work with and support infantry divisions. The second was the armored division, a completely self-contained unit containing tanks, self-propelled artillery, and mechanized infantry.

In addition, the armored division contained all the necessary support arms, including reconnaissance, combat engineers, supply, medical, and maintenance. This provided a single unit with the firepower, mobility, and shock capability necessary for independent combat operations. The mission of the armored division was not to make the initial breakthrough but rather to exploit the breakthrough made by the GHQ tank battalions and infantry divisions.

The armored division had the capacity to supply itself for three days without outside assistance. Its immediate objective was not to engage other enemy armored units but instead to bypass them and attack artillery and supply units and destroy enemy infantry reserves before they could deploy. By not dissipating its armored striking power by engaging enemy tanks, the division would maintain its full capability.

This tactical doctrine was developed simultaneously by a group of young British and American officers in the late 1920s and early 1930s. By adopting the tactics and basic mission of horse cavalry and modernizing it with tanks and other mechanized units, an entirely new type of combat unit was created. The Germans obviously came upon the same idea.

An American heavy armored division deployed in the following manner: The basic unit consisted of a division headquarters, three combat commands, and the division trains. The division headquarters consisted of the headquarters company, a reconnaissance battalion, and a signal company. Each combat command consisted of a headquarters, a recon company, two tank battalions with two medium tank companies and one light tank company each, an armored infantry battalion, an armored field artillery battalion with eighteen M7 self-propelled 105mm howitzers, an armored combat engineer company, an ordnance maintenance company, a medical company, and a supply company. The division trains consisted of their headquarters, the ordnance battalion headquarters company, the medical battalion headquarters company, and the supply battalion headquarters company. In addition, a heavy armored division had attached to it an antiaircraft battalion, a tank destroyer battalion, and a heavy artillery battalion of 155mm GPF rifles mounted on an M12 tank chassis. This gave the division a total strength of approximately 17,000 men and 4,200 vehicles. Had the division ever gotten on the road in single file, in normal march order interval, it would have stretched 150 miles from the head of the column to the end.

Once the division deployed to exploit a breakthrough, it moved out with two combat commands abreast and one in reserve. Each combat command contained two separate task forces, moving as much in parallel as the contours of the land would permit. The front of a heavy armored division could vary in width from several hundred yards up to twenty miles depending upon the terrain. During the daylight hours, each task force had available four P47 fighter-bombers under the direct control of an air force liaison officer who rode in the lead half-track with the task force commander. The task force’s mission was to advance rapidly toward its objective, leaving any resistance to be cleaned up later by the infantry, which might arrive within the next few hours to two days.

At night the combat elements would coil off the road and form a circular perimeter. The tanks and infantry would form the outer perimeter, and the maintenance, medical, and supply units would be inside, where they could do their work. At daybreak, when the combat units moved out, the maintenance unit commander had to make certain critical decisions. All vehicles repaired and ready for action would be returned to their units. All others would be towed to the next stopping point. If there were more vehicles than the wreckers could accommodate, a vehicle collecting point (VCP) was established. The ordnance company commander would detach a maintenance platoon to establish the VCP and repair the vehicles that were left behind. This could take several days. During this period, the maintenance platoon would be completely isolated behind enemy lines and be responsible for its own security.

After the vehicles were repaired, they returned to their original units, and the maintenance platoon went forward to rejoin the ordnance company. In some instances, there would be several VCPs along the route of advance. As soon as any platoon finished its repairs, it would leave the others and return to the company. By utilizing this system, plus the replacement vehicles brought up each day by the ordnance liaison officer, the combat command was able to maintain its effectiveness during long, continuous operations.

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