Artillery — large weapons such as cannons and rocket launchers — came in many forms during World War II and were widely used as offensive weapons of tremendous destructive power by both the Allies and the Axis on land and sea. Artillery weapons included:
Big guns, or cannons, that fire projectiles from a long barrel in a low, flat trajectory. A charge in the projectile detonates on impact. During World War II, big guns were widely used on warships, armored combat vehicles, and tanks to soften up an invasion site or eliminate enemy resistance. A prime example was the use of big guns against German fortifications along the Normandy coast before the Allied landing on D-Day.
Mortars are cannons that fire exploding shells in a high, arcing trajectory that lets them travel over obstacles such as hills or enemy defenses. Most mortars are drop-fire weapons, meaning that the shells were dropped into the barrel of the weapon and propelled via a charge. The standard U.S. Army and Marine Corps mortars were the 60-mm M2 and 81-mm M1, which could be disassembled and carried by backpack. Mortars could also be carried by and fired from half-track vehicles. The 60-mm mortar could fire a maximum of nearly 2,000 yards. The 80-mm mortar could send its projectiles more than 3,200 yards.
Howitzers fired a mid-velocity projectile along a curved trajectory. By firing at a low angle, they could achieve good range, like guns. When fired at a high angle, they could launch shells over obstacles as mortars do.
Rocket launchers, which fire unguided missiles as both weapons and signals.
During World War II, mortars were particularly useful in rough, mountainous terrain because they were easy to use and transport, extremely accurate, and very effective at inflicting damage. Mortars were commonly used by both sides.
Rockets were used by both sides because they were simple to make, easy to launch, and very effective. Ground and naval forces commonly used rockets to bombard enemy-held territory because, though they were unable to penetrate fortifications, they would easily saturate a specific area and inflict heavy casualties on unprotected troops. Rockets also provided excellent protection for troops during amphibious landings.
The United States relied on two main rocket launchers during World War II. One was the so-called calliope system, a sixty-tube launcher fitted on a Sherman tank. It fired 114-mm rockets individually or in a salvo. Sets of multiple 114-mm rocket tubes could also be attached to trucks for easy transportation.
Fire support ships used by American and British forces were usually converted landing ships. The finest of the line was the U.S. Navy's LSMR series, which had twenty automatic-loading, rapid-fire 127-mm rocket launchers in addition to a 127-mm gun.
Rockets were also launched from planes, primarily to attack ground troops and surface-riding submarines. American fighter planes typically used 5-inch (127-mm) rockets, as did Allied antisubmarine aircraft patrolling the Atlantic. The American 5-inch rocket had a 50-pound explosive charge, which created a huge crater when used against ground forces. In 1944, the navy introduced an 11-inch aircraft rocket known as Tiny Tim, which carried a 150-pound warhead.
Germany also made extensive use of rockets as ground artillery, air-to-ground, and air-to-air weapons. The most commonly used German rocket system was the six-tube smoke thrower. Originally created to launch blinding smoke shells, the system eventually became an antipersonnel weapon that was also effective against tanks and other armored vehicles. Americans came to refer to the rockets as “Screaming Meemies” because of the sound they made in flight.