A howitzer is a type of artillery piece for indirect fire at covered targets, with the projectile flying in an arc (lob) trajectory. It was designed to attack enemy positions hidden and protected behind low hills and fortifications, in forests, and in trenches, with the shell falling from above. Thus, the main characteristic of a howitzer is its high-angle maximum elevation, which is between 65° and 70°, while its barrel is usually shorter than that of a cannon. It also has a lower muzzle velocity than a field gun. Therefore, a howitzer is not used as an anti-tank weapons.
World War I trench warfare forced European armies to massively produce and employ howitzers as the field gun (cannon) was only able to shoot in direct fire fashion (horizontally), aiming directly at the enemy troops, which could be seen at the horizon. At the beginning of the 20th century, new weapons, such as the machine gun and breech-loading artillery, with hydro-pneumatic recoil systems, wiped out the cavalry from the battlefield, forcing the infantry to hide in deep trenches to protect themselves from machine gun and field gun fire. This new battlefield landscape forced armies to massively use howitzers.
Howitzers are part of troop artillery (field artillery in foreign armies). They have a caliber of 100 mm or more, a relatively short barrel (from 15 to 30 calibers), a multi-section charge, a range of fire of up to 17 km, and a relatively high rate of fire (a round every other minute or every minute to six rounds per minute depending on the caliber). Most modern howitzers are self-propelled, while the old systems use mechanical traction. Siege howitzers were super heavy artillery pieces, which were especially designed and used to attack reinforced concrete fortifications and bunkers; one example was Big Bertha, which was a 420-mm howitzer employed by the Germans in World War I.
The first howitzers were built in Europe in the 15th century (Italy and Germany) and were used for firing stone-filled canisters. In the second half of the 16th century, howitzers began firing explosive shells. In Russia the first howitzers were built in the middle of the 16th century. They were called gakovnitsy, gaufnitsy, and gafunitsy. In the 1760’s Russia developed longer howitzers, which were named unicorns. The change from smooth-bore to rifled guns in the 1860’s led to the building of rifled howitzers. The greater use of field fortifications in the wars in the second half of the 19th century increased the need for howitzers. They were widely used in all armies in the two world wars. During the Great Patriotic War (1941-45) the highest performance indexes were displayed by the Soviet 122-, 152-, and 203-mm howitzers.
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| A World War 1 Italian howitzer: Obice da 149-mm. |