In 1936, a civil war erupted in Spain between the Republicans and Nationalists, those that backed General Franco. During this conflict, the country was a proving grounds of sorts, a place where new weapons were tested and new tactics were developed. Of course, things did not progress without tanks. Republican Spain received over 300 T-26 and BT-5 tanks from the USSR, and the Nationalists were reinforced with German PzI and Italian CV 35 tanks.
Spain is a very unique country, with many escarpments and highlands, separating it into half-isolated regions. In order to transport tanks in between battles, the Republicans actively used powerful German and American trucks. They had to be careful, as a deviation of several centimeters on the narrow mountain roads meant certain death. The risk gave a return, however, as tanks could be transported over 400 km in less than a day.
This was very important for the Republican army, which had to constantly plug holes in its front lines during Nationalist offensives. Tanks were used for this purpose, and could stay in battle for days. Crews were exhausted to their limits. Eyewitnesses record nervous breakdowns and hallucinations.
The tankers' courage was great: they attacked 10-15 times per day, fought with broken ribs, with burns and wounds. If necessary, they fought in tanks with holes in their armour. When it was necessary to replace a dead or disabled tanker, any soldier would do as a replacement. The crew would explain to him how to load the gun on the way to battle, and that was the end of training.
In these conditions, there was no cooperation among the tanks or with any other types of forces. In Spain, tanks fought in small groups, or even individually, without complicated maneuvers, firing their cannon at all targets. The tanks fired while stationary, as it was easier to hit that way. The crews didn't conserve ammunition; tanks shot up to 7 loads of AP shells per day. They weren't spared even when shooting at machineguns, as the precision of the T-26's gun allowed them to hit even small targets.
Local War School
Cooperation was a serious problem for the Republican army. In theory, tanks were to follow infantry, and when it arrived at the enemy lines, overtake it, attack the enemy, and again back out behind their infantry. In practice, tankers always complained about infantry that was "lying around sightseeing" instead of fighting.
Reconnaissance was also poor. At best, tankers knew the direction the enemy is in. Terrain was not observed, and tanks went into battle blind.
The Nationalists, on the other hand, fought in a more organized fashion. At first, defenders were "worked over" with bombs or artillery. Then, tanks with infantry attacked. Even well trained foreign volunteers (interbrigades) could not withstand such an attack. When the Nationalists captured even a scrap of land, they would dig in, and concrete fortifications would appear within two or three days. Artillery followed close behind infantry.
The T-26 was rightfully called the main strike force of the Republican army, equal to its aircraft. It was praised for its accurate and reliable gun, reliable engine, and respectable speed. The engines worked fro 100-150 hours, even in cases where they ran for nearly a whole day straight with no complaints. In tank on tank battles, German PzIs and Italian CV 35s were no match for the T-26. They were frequently referred to as tankettes instead of real tanks. This experience caused machinegun tanks to disappear quickly.
From a purely technical point of view, the Republicans surpassed the Nationalists. However, the latter fought these tanks even when they had no anti-tank guns. Improvised measures such as petrol bombs or barrels of sap dug into the ground were used.
Crews quickly learned to shoot off balconies where petrol bombs were thrown from. However, it was still hard to fight in populated areas. The enemy could be anywhere, and spotting him from inside the vehicle was a tough job. To make matters worse, Spanish settlements were built like miniature fortresses for centuries, with narrow winding streets, dead ends, and squares that were open from all sides. Walls could have houses with walls up to 2 meters thick, and 4 meter tall stone walls were common. After the first few fights, tanks were forbidden from entering towns, and ordered to surround them and shoot from a safe distance.
Armour lost to the shell
The main enemy of tanks in Spain were anti-tank guns. They appeared during WWI, but became very common in the 1930s. The USSR already developed methods of fighting them, and instructed Spanish tankers, but spotting a stout 37 mm gun from a T-26 was hard. Considering that the armour could be penetrated from 200-300 meters by an armour piercing bullet, the fate of a tank hit by a shell was not enviable. The Nationalists got more and more guns, and it was more and more important to find them.
The use of anti-tank guns in the Spanish Civil War put an end to tankette development and led to the appearance of tanks with shellproof armour. The idea of putting armour at an angle to ricochet shells was also born. An understanding evolved that tanks need improved optics so they could see better.
Only a short time remained before tanks built based on the experience in Spain would be tested by a large war.
Article author: Evgeniy Belash
Original article available here.