Anti-tank Rockets - Development Between The World Wars

Development Between The World Wars

Lack of consensus on the design and use of the tank after the First World War also influenced the development of its anti-tank countermeasures. However, because Germany was restricted in its military capability, and there were no other challenges to France and Britain, very little development took place in anti-tank warfare until the 1930s.

The Interwar period was dominated by the strategic thinking with fortified borders at its core. These included obstacles consisted of natural features such as ditches, streams and urban areas, or constructed obstacles such as anti-tank ditches, minefields, dragon's teeth, or log barriers. The pinnacle of this strategic thinking was considered to be the Maginot Line which replaced infantry-filled trenches with artillery-filled bunkers, including casemates housing 37 or 47 mm anti-tank guns, and steel turrets armed with a pair of machine guns and a 25 mm anti-tank gun, although Germany was forbidden to produce tanks. The construction was partially based on the Allied experience with the Hindenburg Line which was breached with tank support during the battles of Cambrai and St. Quentin Canal, although German Command was more impressed by the surprise achieved by the Canadian troops at the Battle of the Canal du Nord. This came to influence their planning in 1940.

The Maginot line defenses - up to 16 miles deep from the forward positions to the rear line - were intended to prevent a surprise attack and delay any attack while the French Army was mobilized. With the relative numerical inferiority between the France and Germany, it was a more effective use of manpower. Within the line passive anti-tank obstacles were supported by anti-infantry and anti-tank bunkers. After Belgium declared neutrality in 1936, France began work on extending the line along the Belgium border.

Improved artillery was seen as the quickest solution to anti-tank defense, and one of the earliest post-war anti-tank gun designs was the 25 mm Hotchkiss model from France. It was intended to replace an Atelier de Puteaux 37 mm weapon designed in 1916 to destroy machine gun positions. Rheinmetall commenced design of a 37 mm anti-tank gun in 1924 and the first guns were produced in 1928 as 3.7 cm Pak L/45, later adopted in Wehrmacht service as 3.7 cm Pak 36. It made an appearance during the Spanish Civil War, as did the Bofors 37 mm developed in Sweden, and used by many early Second World War combatants. The British Army accepted for service the (40 mm) Ordnance QF 2 pounder which was developed as a tank gun. The Soviet Red Army after the Russian Civil War also begun a search for an anti-tank gun with a French Hotchkiss 37 mm L.33 tank gun, but soon upgraded this to a higher velocity L.45 Model 1935 while also making a licensed copy of the German 3.7 cm PaK 35. However, the Red Army was almost immediately taught a lesson about anti-tank warfare when a tank battalion sent to aid the Spanish Communists in the Spanish Civil War was almost entirely destroyed in an engagement.

At this time the predominant ammunition used against tanks was the armor piercing kinetic energy shell that defeated armor by direct pressure, spiking or punching through it. During the late 1930s shaped charge ammunition was experimented with that used chemical energy for armor penetration. More difficult to manufacture, its advantage was in that on impact it created a high-velocity jet of molten metal which created tremendously high pressures, hydrodynamically deforming the armor. The depth of the penetration, though proportional to the length of the jet and the square root of its density, is also dependent on the strength of the armor. With the development of this new ammunition begun more advanced research into steel manufacturing, and development of spaced armor that caused "jet waver" by detonating prematurely or at the wrong angle to the surface of the main armor.

The only significant attempt to experiment in the use of tanks in the late 1920s was that of the British Army's Experimental Mechanized Force that influenced future development of tanks, armored troops and entire armies of both its future enemies and allies in the next war.

In Spain the anti-tank defense of the Nationalists was organized by the Wehrmacht officers, and the anti-tank guns were incorporated into a system of obstacles that were constructed with the intent to stop an attack by tanks by slowing it down, separating them from supporting infantry (advancing on foot) with machine-gun and mortar fire, and forcing tanks to conduct deliberate head-on assaults with engineer support, or seek a less-defended area to attack. Minefields laid with purpose-designed mines were used for the first time, destroying tank tracks, and forcing combat engineers to clear them on foot. Delay meant that Nationalist field artillery could engage the lightly armored Soviet tanks. This meant a change in Republican operational and eventually strategic planning, and a more protracted combat operations, with more casualties at a greater cost.

The only change to the German anti-tank tactics of the First World War was that now an effective anti-tank weapon was available to support the defending infantry. However, the Soviet tanks armed with 45 mm guns easily destroyed the German light tanks.

Ironically, in the early 1930s until the Spanish War, German officers were conducting secret testing of a new way of employing tanks, infantry and artillery offensively in the Soviet Union with the cooperation of the Red Army. In Germany these developments eventually culminated in tactics that later came to be known as Blitzkrieg, while in the Soviet Union they formed the core of the deep battle operational doctrine. The successful test of the latter was during the Battles of Khalkhin Gol although the Red Army foundered on the Mannerheim Line in 1940, largely due to the purge in the Officer Corps, claiming many of the senior proponents of the new doctrine. Anti-tank artillery would be included in mobile tank-led Wehrmacht and Red Army units due to the possibility of encountering enemy tanks in a meeting engagement.

The new doctrines of using the tank, were divided into infantry and cavalry schools of thought. The former regarded the tank as a mobile artillery system to be used for infantry support. This suggested that the infantry needed to be armed with integral anti-tank weapons. The latter advocated use of tanks in the traditional cavalry way of high-tempo attacks intended to outflank the enemy infantry and sever its communication lines. This approach suggested that the tank was the best anti-tank system, and only limited anti-tank troops were required to accompany them. For this reason the late 30s tank configurations came in a great diversity, ranging from light tankettes and cavalry tanks to multi-turreted heavy tanks resembling bunkers, all of which had to be considered in training by the anti-tank artillery troops. The development of these doctrines was the most significant influence on the rapid development in anti-tank technology and tactics in the Second World War.