Mortar

A portable muzzle-loading cannon that fires shells indirectly at low velocities, short ranges, and high, arcing trajectories. Mortar is contrasted with larger artillery pieces, which fire at high velocities, long ranges, and low arcs. Present-day mortars consist of a lightweight tube that rests on a base plate and is supported by a bipod. The weapon is operated by dropping a mortar shell onto a firing pin in the tube that detonates the propellant and fires the shell.

Types of Ammunition

In modern warfare, mortars up to 81mm can be carried by infantry and used as a small-scale, limited-range substitute for artillery. Mortars have the advantage of portability due to their size, freedom of movement without the need for logistical support, and capacity to be fired from a trench or defilade—protecting the operators from direct return fire. Due to its high trajectory, mortar fire can be used against enemy positions not protected by overhead cover such as trench lines, gun pits, or fighting positions.

History

The need to attack enemy strongholds from a distance, combined with advances in the field of metalwork, resulted in the invention of increasingly complex siege devices. Mortars were first used as siege weapons around the year 1500. These simple devices consisted of a tube roughly one meter in length and weighing more than 100 kilograms. Inserted into the ground at an angle, a round was dropped down the tube and propelled upward by an explosive charge. These weapons were popular in early modern European warfare despite their inaccuracy.

Although crude, unwieldy ancestors of the modern mortar were employed by the armies of Napoleon and the North and South in the American Civil War. The progenitor of most present-day mortars is the Stokes Mortar developed by the British Army in World War I. Designed in January 1915 by F.W.C. Stokes, it was used to counter German superiority. This weapons system could fire up to 22 rounds per minute at a range of 1,100 meters. The Stokes would be standard issue for the British through World War II.

The mortar made its presence felt in the fierce ground fighting of World War II. Mortars cleared the way for advancing Allied armies from the fields of France to the rugged hills of Pacific island outposts. The mortar also served American and allied fighting forces in Korea and Vietnam, in which enemy forces took advantage of the hilly landscape for concealment and were not always easily dislodged by direct fire.

Insurgents in Iraq have effectively used the firepower and mobility of mortars against American and coalition forces. A mortar can be easily fired on a coalition position and be withdrawn by its operators before return fire can be directed. Insurgents have also used mortars against concentrations of civilians and civic leaders to cause terror and political instability.

Since their inception 500 years ago, mortars have provided commanders in the field with an increasingly mobile means of attacking protected enemy positions with indirect fire. Although possibly ill-suited to present-day urban warfare operations in which the risk of civilian casualties is high, mortars continue to be used by our armed forces in an age where national security demands mobility.

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