Towed or Self-Propelled: U.S. Army Tank Destroyers on the Eve of Normandy

By Squire – major thanks!

As the United States Army contemplated shifting operations to western Europe in the waning months of 1943, confusion settled in about how to employ tank destroyers. The deserts of North Africa, it seems, steered thinking in a bizarre direction. Haunted by the poor performance of the half-track M3 while impressed by the British employment of dug-in anti-tank guns, the U.S. Army, under the influence of Lieutenant General Lesley McNair, began to value the towed tank destroyer over its self-propelled brethren.

According to a report of the General Board convened in 1945 to study the effectiveness of U.S. forces in the European Theater, “those officers who had been through the African Campaign, who had become indoctrinated with the British defense against armor, and who had seen the impossibility of concealing the self-propelled gun in open terrain, requested towed tank destroyer battalions.” Indeed, as late as December 1943, the U.S. Army issued an order converting twenty self-propelled battalions to towed to achieve a more balanced force. It also changed trans-Atlantic shipping priorities to increase the number of towed battalions in England in advance of the Normandy invasion. This change reflected a remarkable shift in emphasis just months before the Overlord campaign.

The decision, however, failed both to appreciate the latest developments in tank destroyer technology and anticipate the impact of terrain on tactical employment. By mid-July 1943, the M10 tank destroyer, equipped with a 3-inch gun, largely replaced the M3 halftrack Gun Motor Carriage, equipped with a 75-mm cannon. The M10 offered a protection and mobility with which neither the halftrack nor its towed counterpart could compete. Boasting the same 3-inch firepower, towed anti-tank battalions lacked protection and required considerable time to emplace and displace. Nevertheless, placed along predictable avenues of approach in the open desert, the towed guns could prove remarkably effective.

Perhaps predictably, the Louisiana maneuvers in 1943 and training in England in early 1944 exposed the flaws in this approach to tank destroyer employment. Requiring additional time to unload and enter action, the towed guns, along with their prime movers—the trucks responsible for transporting them—appeared excessively vulnerable to enemy fire. Reacting to these observations, planners reversed course and subsequently reduced the role of towed anti-tank units in the initial invasion force to just one battalion.

Combat in the hedgerow country quickly reaffirmed the value of the self-propelled tank destroyer, or at least the inutility of towed systems. The towed guns struggled to shoot direct fire engagements over the hedgerows and lacked the armor required to push forward aggressively where the vegetation and terrain allowed for fields of fire. Additionally, infantry commanders disliked the towed guns’ comparative lack of mobility once in position and their general lack of firepower.

Within a month of landing at Normandy, even the self-propelled M10 failed to meet commanders’ demands for firepower. Just two months prior, the U.S. Army in Europe had rejected offers to replace M10s with the newer M36 sporting a 90mm gun. By July 6, 1944, however, it requested that all M10 battalions be converted to M36s and asked that any future tank destroyer organizations be equipped with either the M18 or M36.

Two images are intended to show the difference in terrain:

German Panzers IIs in North Africa
German Panzers IIs in North Africa

The Bocage Country in France
The towed M3 37mm being emplaced
M10 Tank Destroyer in Normandy

Sources

The General Board, United States Forces, European Theater. Report on Study of Organization, Equipment, and Tactical Employment of Tank Destroyer Units. 1945.

Harry Yeide. The Tank Killers: A History of America’s World War II Tank Destroyer Force. Philadelphia: Casemate, 2007.

Steven J. Zaloga. U.S. Tank and Tank Destroyer Battalions in the ETO 1944-1945. Oxford: Osprey Publishing 2005.