Artillery Bombardment

Artillery Bombardment, full-scale attack by large guns used in military operations on land. The first cannons, which were used in battle in the 14th century, were crude wrought-iron tubes that fired large stones. The English are reported to have used cannon at the Battle of Crecy in 1346. Between 1450 and 1850 cannon were made from cast bronze, iron, or brass. By 1500 metal shot had become widely adopted. Fortifications changed to face this new threat, high walls could be battered down by siege artillery and so deep, rather than high, defences were introduced. In the late 17th century the French engineer Vauban pioneered huge star-shaped fortifications which allowed the defenders to use their artillery and muskets in interlocking fields or fire. In 1784 the shrapnel shell was developed, which contained musket balls or small pieces of scrap metal and was highly lethal against infantry or cavalry. The 19th century saw rapid changes in artillery design: with the introduction of rifled guns, breech loading, smokeless powder, and the long recoil cylinder, guns could be fired faster and more accurately and battlefields were no longer covered in clouds of white smoke. Field telephones and later radio allowed guns to be used in indirect fire, with an observer correcting their fall of shot while the guns remained behind cover. Until then direct fire had been used, where crews could see their target and correct their aim accordingly.

In World War I artillery was used extensively for long-range bombardment and in 1918 the Germans fired shells from distances of more then 120 km (74.5 mi) at Paris. World War I also saw the development of modern mortars and the use of elaborate massed artillery barrages. Guns were used to fire shells containing toxic chemicals (see Small Arms). In World War II tank and anti-tank guns were developed and artillery was mounted on tracked chassis to give it greater battlefield mobility. Artillery is normally divided into two groups: tube and rocket. Tube artillery comprises conventional guns with rifled barrels which in the West are usually 105-mm or 155-mm calibre weapons. There are guns with larger calibres, but these are less common. Rocket artillery may comprise a single surface-to-surface missile (SSM) travelling on a ballistic path to hit targets on the battlefield, but is more likely to take the form of multibarrelled rocket launchers firing a barrage of unguided rockets into a target area (see Ballistics).

Artillery can be very accurate, but because the shells may pass into the atmosphere and are subject to drag and the forces of gravity, there is always a degree of inaccuracy. Firing must therefore be corrected by a forward observation officer, who can see the target and where the shells have landed, and who sends corrections back to the guns by radio. Indirect fire is made when gunners are unable to see their rounds landing on the target. Direct fire is less common; here the gunners may be engaging enemy tanks or a fortified position. Artillery shells damage or destroy the target by the force of the explosion and by the fragments or shrapnel produced when the shell case shatters. Shells can be fused to explode on impact, with a delay or in the air above troops or vehicles. Shells may contain high explosive (HE) or white phosphorus (WP) which produces white smoke and will also burn men and buildings (see Explosives).

Rocket artillery tends to be more destructive than tube artillery as it has a thinner casing and therefore carries more explosive. Multiple launchers deliver a salvo of rockets into the target area which can be very destructive. Modern rockets carry warheads designed to explode at a predetermined height and scatter smaller submunitions over the target. Satellite navigation systems, laser rangefinders, and secure radios have ensured that both tube and rocket artillery are more accurate. Advanced fuses and warheads have made both forms of artillery bombardment highly destructive.