Grenade
A grenade is a small explosive weapon typically thrown by hand, but can also refer to a shell shot from the muzzle of a rifle or a grenade launcher. A modern hand grenade generally consists of an explosive charge, a detonator mechanism, an internal striker to trigger the detonator, an arming safety secured by a transport safety. The user removes the transport safety before throwing, and once the grenade leaves the hand the arming safety gets released, allowing the striker to trigger a primer that ignites a fuze, which burns down to the detonator and explodes the main charge.
Grenades work by dispersing fragments, shockwaves, chemical aerosols, fire or a jet of molten metal. Their outer casings, generally made of a hard synthetic material or steel, are designed to rupture and fragment on detonation, sending out numerous fragments as fast-flying projectiles. In modern grenades, a pre-formed fragmentation matrix inside the grenade is commonly used, which may be spherical, cuboid, wire or notched wire. Most anti-personnel grenades are designed to detonate either after a time delay or on impact.
Grenades are often spherical, cylindrical, ovoid or truncated ovoid in shape, and of a size that fits the hand of an average-sized adult. Some grenades are mounted at the end of a handle and known as "stick grenades". The stick design provides leverage for throwing longer distances, but at the cost of additional weight and length, and has been considered obsolete by western countries since the Second World War and Cold War periods. A friction igniter inside the handle or on the top of the grenade head was used to initiate the fuse.
Etymology
The origin of the English word grenade is disputed. Some derive it from the French word spelled exactly the same, meaning "pomegranate", while others claim it is taken more directly from the Latin, meaning "filled with grain". The first use of the word for explosives comes from the August 1536 siege of Arles by the Emperor Charles V, while its first recorded use in English dates from 1591.History
Pre-gunpowder
Rudimentary incendiary grenades appeared in the Byzantine Empire, not long after the reign of Leo III. The Byzantine army learned that Greek fire, a Byzantine invention of the previous century, could not only be thrown by flamethrowers at the enemy but also in stone and ceramic jars. Later, glass containers were employed.Gunpowder
In Song China, weapons known as 'thunder crash bombs' were created when soldiers packed gunpowder into ceramic or metal containers fitted with fuses. A 1044 military book, Wujing Zongyao, described various gunpowder recipes in which one can find, according to Joseph Needham, the prototype of the modern hand grenade.File:FireLanceAndGrenade10thCenturyDunhuang.jpg|thumb|left|Earliest known representation of a gun and a grenade, Dunhuang, 10th century AD
Grenade-like devices were also known in ancient India. In a 12th-century Persian historiography, the Mojmal al-Tawarikh, a terracotta elephant filled with explosives set with a fuse was placed hidden in the van and exploded as the invading army approached.
A type of grenade called the 'flying impact thunder crash bomb' was developed in the late 16th century and first used in September 1, 1592 by the Joseon Dynasty during the Japanese invasions of Korea. The grenade was 20 cm in diameter, weighed 10 kg, and had a cast iron shell. It contained iron pellets, and an adjustable fuse. The grenade was used with a dedicated grenade launcher called a 'wangu'. It was used in both the besieging and defense of fortifications, to great effect.
There is a documented precedent for the use of hand grenades by Catalan troops. At the very least, they were already utilized during the Siege of Bonifacio in 1420. Another specific historical instance occurred in 1433: The fleet of Alfonso the Magnanimous, which set sail for Sicily, loaded 200,000 units of primitive "magranes de coure" in Barcelona. The historical account describes them as follows:
"...It also carried 200,000 copper pomegranates filled with gunpowder, and when they set fire to them they made a great noise, and, as the pieces shattered, they did so much damage that they knocked to the ground anyone they touched..." — Melcior Miralles: Chronicle and Diary of the Chaplain of Alfonso the Magnanimous.The key innovation here was the fragmentation effect. Older grenades relied mostly on fire to burn the enemy. The Catalan copper grenades were designed to explode and spray metal shrapnel, making them a true ancestor of the modern fragmentation grenade. Moroever the quantity indicates they were a standard issue munition, not just an experimental prototype
The first cast-iron bombshells and grenades appeared in Europe in 1467, where their initial role was with the besieging and defense of castles and fortifications. A hoard of several hundred ceramic hand grenades was discovered during construction in front of a bastion of the Bavarian city of Ingolstadt, Germany, dated to the 17th century. Many of the grenades retained their original black powder loads and igniters. The grenades were most likely intentionally dumped in the moat of the bastion prior to 1723.
By the mid-17th century, infantry known as "grenadiers" began to emerge in the armies of Europe, who specialized in shock and close quarters combat, mostly with the usage of grenades and fierce melee combat. In 1643, it is possible that grenados were thrown amongst the Welsh at Holt Bridge during the English Civil War. The word grenade was also used during the events surrounding the Glorious Revolution in 1688, where cricket ball-sized iron spheres packed with gunpowder and fitted with slow-burning wicks were first used against the Jacobites in the battles of Killiecrankie and Glen Shiel. These grenades were not very effective owing both to the unreliability of their fuse and the inconsistent times to detonation as a result, saw little use. Grenades were also used during the Golden Age of Piracy, especially during boarding actions; pirate Captain Thompson used "vast numbers of powder flasks, grenade shells, and stinkpots" to defeat two pirate-hunters sent by the Governor of Jamaica in 1721. By the 18th century, the popularity of hand grenades was declining
Mexican forces used grenades in the Battle of the Alamo.
Improvised grenades were increasingly used from the mid-19th century, the confines of trenches enhancing the effect of small explosive devices. In a letter to his sister, Colonel Hugh Robert Hibbert described an improvised grenade that was employed by British troops during the Crimean War : Hand grenades were used by French and Russian forces during the Siege of Sebastopol.
File:Ketchum cs.jpg|thumb|A cross-section of a Ketchum grenade, used during the American Civil War
During the Battle of Fort Sumter, grenades were kept at critical points of the fort such as the room over the gateway. About 93,200 Ketchum grenades were procured by the Union Army throughout the American Civil war; those weapons were used in the sieges of Vicksburg, Port Hudson and Petersburg. Grenades were issued to United States Ram Fleet and Union Navy vessels to repel boarders.The Augusta Arsenal manufactured around 13,000 hand grenades between 1863 and 1865, Confederate troops also used improvised grenades made from artillery shells to defend their positions.
In March 1868, during the Paraguayan War, the Paraguayan troops used hand grenades in their attempt to board Brazilian ironclad warships with canoes.
Hand grenades were used on naval engagements during the War of the Pacific.
British troops used hand grenades in Sudan between 1884 and 1885. By 1890, the British Army had totally removed grenades from its inventory
During the Siege of Mafeking, in the Second Boer War, the defenders used fishing rods and a mechanical spring device to throw improvised grenades.
Improvised hand grenades were used to great effect by the Russian defenders of Port Arthur during the Russo-Japanese War. At first, they were improvised from old iron cases or mountain gun shells. Later, they were replaced with cut down hell casings from quick-firing artillery; filled with dynamite or gun-cotton, and fitted with safety fuses. The workshops in Port Arthur could turn out 2,500 grenades in 24 hours. In the month of August alone 18,000 grenades were prepared.
Japanese forces also used grenades during the Russo-Japanese War. The first Japanese grenades were made from tin cans or bamboo tubes filled with gun-cotton, and fitted with fuses; they were lit with matches but later on a percussion arrangement was improvised by means of a rifle cartridge and steel wire.Japanese cavalry was also armed with grenades and threw them under the horses of the enemy when pursued.
Development of modern grenades
Around the turn of the 20th century, the ineffectiveness of the available types of hand grenades, coupled with their levels of danger to the user and difficulty of operation, meant that they were regarded as increasingly obsolete pieces of military equipment. In 1902, the British War Office announced that hand grenades were obsolete and had no place in modern warfare. But, within two years, following the success of improvised grenades in the trench warfare conditions of the Russo-Japanese War, and reports from General Sir Aylmer Haldane, a British observer of the conflict, a reassessment was quickly made and the Board of Ordnance was instructed to develop a practical hand grenade. Various models using a percussion fuze were built, but this type of fuze suffered from various practical problems, and they were not commissioned in large numbers.In 1904, Serbia adopted a grenade designed by Major Miodrag Vasić; it was partially inspired by copies of Bulgarian grenades manufactured by the Serbian Chetnik Organization.
Marten Hale, known for patenting the Hales rifle grenade, developed a modern hand grenade in 1906 but was unsuccessful in persuading the British Army to adopt the weapon until 1913. Hale's chief competitor was Nils Waltersen Aasen, who invented his design in 1906 in Norway, receiving a patent for it in England. Aasen began his experiments with developing a grenade while serving as a sergeant in the Oscarsborg Fortress. Aasen formed the Aasenske Granatkompani in Denmark, which before the First World War produced and exported hand grenades in large numbers across Europe. He had success in marketing his weapon to the French and was appointed as a Knight of the French Legion of Honour in 1916 for the invention.
The Royal Laboratory developed the No. 1 grenade in 1908. It contained explosive material with an iron fragmentation band, with an impact fuze, detonating when the top of the grenade hit the ground. A long cane handle allowed the user to throw the grenade farther than the blast of the explosion. It suffered from the handicap that the percussion fuse was armed before throwing, which meant that if the user was in a trench or other confined space, he was apt to detonate it and kill himself when he drew back his arm to throw it.
An improved version of Vasić's design was adopted by the Serbian Army in 1912; the grenade provide very useful during the First Balkan War, specially during the Siege of Adrianopole.
Before the beginning of the Second Balkan War, Serbian General Stepa Stepanović ordered that bomb equipped squads should be formed in all companies of the 4th, 13th, 14th, 15th and 20th Infantry Regiments of the Timočka Division.
The German Army adopted the Kugelhandgranate in 1913; it was meant to be used by pioneers to assault enemy positions.
Early in World War I, combatant nations only had small grenades, similar to Hales' and Aasen's design. The Italian Besozzi grenade had a five-second fuze with a match-tip that was ignited by striking on a ring on the soldier's hand.
File:N°36+ plaque de base.jpg|thumb|left|upright|The Mills bomb the first modern fragmentation grenade was used in the trenches from 1915.
William Mills, a hand grenade designer from Sunderland, patented, developed and manufactured the "Mills bomb" at the Mills Munition Factory in Birmingham, England in 1915, designating it the No.5. It was described as the first "safe grenade". They were explosive-filled steel canisters with a triggering pin and a distinctive deeply notched surface. This segmentation is often erroneously thought to aid fragmentation, though Mills' own notes show the external grooves were purely to aid the soldier to grip the weapon. Improved fragmentation designs were later made with the notches on the inside, but at that time they would have been too expensive to produce. The external segmentation of the original Mills bomb was retained, as it provided a positive grip surface. This basic "pin-and-pineapple" design is still used in some modern grenades.
After the Second World War, the general design of hand grenades has been fundamentally unchanged, with pin-and-lever being the predominant igniter system with the major powers, though incremental and evolutionary improvements continuously were made. In 2012, Spränghandgranat 07 was announced as the first major innovation in the area of handgrenades since the Great War.
Developed by Ian Kinley at Försvarets Materielverk, shgr 07 is a self-righting, jumping hand grenade containing some 1,900 balls that covers a cone 10 metres in diameter with the centre about 2 metres in height. This minimize the dangers outside the lethal zone as there is little to no random scattering of fragments from the blast.