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Kinetic Projectile
A kinetic energy weapon (also known as kinetic weapon, kinetic energy warhead, kinetic warhead, kinetic projectile, kinetic kill vehicle) is a projectile weapon based solely on a projectile's kinetic energy to inflict damage to a target, instead of using any explosive, incendiary, chemical or radiological payload. All kinetic weapons work by attaining a high flight speedgenerally supersonic or even up to hypervelocityand collide with their targets, converting their kinetic energy and relative impulse into destructive shock waves, heat and cavitation. In kinetic weapons with unpowered flight, the muzzle velocity or launch velocity often determines the effective range and potential damage of the kinetic projectile. Kinetic weapons are the oldest and most common ranged weapons used in human history, with the projectiles varying from blunt projectiles such as rocks and round shots, pointed missiles such as arrows, bolts, darts, and javelins, to modern tapered high-ve ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Unpowered Flight
Unpowered flight is the ability to stay airborne for a period of time without using any power source. There are several types of unpowered flight. Some have been exploited by nature, others by humankind, and some by both. Unpowered aircraft are aerial vehicles that can fly without any propulsion mechanism. The ability to fly short or long distances without power has evolved many times in nature. Many creatures capable of sustained wing-powered flight also soar unpowered for much of the time they are airborne. Flight without power Classification of flight methods Pennycuick divides animal flight into three types: parachuting, gliding and powered. He observes however that these have no sharp boundaries. For example, at one point he sees parachutes as unpowered and as a primitive form of soaring, while soaring itself he sees as being powered by air movement (wind). Other methods, such as lighter-than-air flight, are used only by man. This article makes the following distinctions b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flechette
A flechette or flèchette ( ) is a pointed, fin-stabilized steel projectile. The name comes from French (from \''wikt:flèche, flèche''), meaning "little arrow" or "Dart (missile), dart", and sometimes retains the grave accent in English: flèchette. They have been used as ballistic weapons since World War I. Delivery systems and methods of launching flechettes vary, from a single shot, to thousands in a single explosive round. The use of flechettes as antipersonnel weapons has been controversial; however in war is not prohibited by the Hague Conventions of 1899 and 1907, Hague Convention. Air-dropped The weapons were designed to be dropped from an aircraft. They contained no explosive charge but as they fell they developed significant kinetic energy making them lethal and able to easily penetrate soft cover such as jungle canopy, several inches of sand or light armor. During World War I, flechettes were dropped from aircraft to attack infantry and were able to pierce helmets ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bullet
A bullet is a kinetic projectile, a component of firearm ammunition that is shot from a gun barrel. They are made of a variety of materials, such as copper, lead, steel, polymer, rubber and even wax; and are made in various shapes and constructions (depending on the intended applications), including specialized functions such as hunting, target shooting, training, and combat. Bullets are often tapered, making them more aerodynamic. Bullet size is expressed by weight and diameter (referred to as "caliber") in both imperial and metric measurement systems. Bullets do not normally contain explosives but strike or damage the intended target by transferring kinetic energy upon impact and penetration. Description The term ''bullet'' is from Early French, originating as the diminutive of the word ''boulle'' (''boullet''), which means "small ball". Bullets are available singly (as in muzzle-loading and cap and ball firearms) but are more often packaged with propellant as a cartri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Javelin
A javelin is a light spear designed primarily to be thrown, historically as a ranged weapon. Today, the javelin is predominantly used for sporting purposes such as the javelin throw. The javelin is nearly always thrown by hand, unlike the sling (weapon), sling, bow and arrow, bow, and crossbow, which launch projectiles with the aid of a hand-held mechanism. However, devices do exist to assist the javelin thrower in achieving greater distances, such as spear-throwers or the amentum. A warrior or soldier armed primarily with one or more javelins is a javelineer. The word javelin comes from Middle English and it derives from Old French ''javelin'', a diminutive of ''javelot'', which meant spear. The word ''javelot'' probably originated from one of the Celtic languages. Prehistory There is archaeological evidence that javelins and throwing sticks were already in use by the last phase of the Lower Paleolithic. Seven spear-like objects were found in a coal mine in the city of Schön ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dart (missile)
Darts are airborne ranged weapons. They are designed to fly such that a sharp, often weighted point will strike first. They can be distinguished from javelins by the presence of fletching (feathers on the tail) and a shaft that is shorter or more flexible. Darts can be propelled by hand or with the aid of a hand-held implement such as a blowgun. They can be distinguished from arrows because they are not used with a Bow and arrow, bow. Darts have been used since pre-history. The plumbatae were lead-weighted darts thrown by infantrymen in Antiquity and the Middle Ages. Darts can be propelled by a number of means. The atlatl uses leverage to increase the velocity of the dart, the kestros (weapon), kestros increases the range of propelled darts using a sling, and the exhalation of a person's breath through a blowgun propels small stone points or poisoned needles with pneumatic force. In the modern era, darts have been used for recreation in lawn darts and the game of darts. Histo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crossbow Bolt
A bolt or quarrel is a dart-like projectile used by crossbows. The word ''quarrel'' is from the Old French ''quarrel'' (> French ''carreau'') "square thing", specialized use as ''quarrel d'arcbaleste'' (> ''carreau d'arbalète'') "crossbow quarrel", referring to their typically square heads. Although their lengths vary, bolts are typically shorter and heavier than traditional arrows shot with longbows. Parts of the bolt Point The point, also called the ''head'' or the ''tip'', is the pointed and weighted front end of the bolt, which is sharp and hard so that it can penetrate the target. Shaft The shaft is the main body of the bolt to which other parts of the bolt are attached. In modern times it is normally made of carbon fibre or aluminium alloy (or sometimes both aluminum and carbon fibre are used), and is very lightweight for its strength. Shafts come with varying degrees of stiffness — referred to as the " spine" of the bolt. The more resistant to bending a bolt ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arrow
An arrow is a fin-stabilized projectile launched by a bow. A typical arrow usually consists of a long, stiff, straight shaft with a weighty (and usually sharp and pointed) arrowhead attached to the front end, multiple fin-like stabilizers called fletchings mounted near the rear, and a slot at the rear end called a nock for engaging the bowstring. A container or bag carrying additional arrows for convenient reloading is called a quiver. The use of bows and arrows by humans predates recorded history and is common to most cultures. A craftsman who makes arrows is a fletcher, and one who makes arrowheads is an arrowsmith.Paterson ''Encyclopaedia of Archery'' p. 56 History The oldest evidence of likely arrowheads, dating to years ago, were found in Sibudu Cave, current South Africa.Backwell L, d'Errico F, Wadley L.(2008). Middle Stone Age bone tools from the Howiesons Poort layers, Sibudu Cave, South Africa. Journal of Archaeological Science, 35:1566–1580. Backwell L ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Round Shot
A round shot (also called solid shot or simply ball) is a solid spherical projectile without explosive charge, launched from a gun. Its diameter is slightly less than the bore of the barrel from which it is shot. A round shot fired from a large-caliber gun is also called a cannonball. The cast iron cannonball was introduced by French artillery engineers after 1450; it had the capacity to reduce traditional English castle wall fortifications to rubble. French armories would cast a tubular cannon body in a single piece, and cannonballs took the shape of a sphere initially made from stone material. Advances in gunpowder manufacturing soon led the replacement of stone cannonballs with cast iron ones. Round shot was made in early times from dressed stone, referred to as gunstone (Middle English: ''gunneston''), but by the 17th century, from iron. It was used as the most accurate projectile that could be fired by a smoothbore cannon, used to batter the wooden hulls of oppos ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rock (geology)
In geology, rock (or stone) is any naturally occurring solid mass or aggregate of minerals or mineraloid matter. It is categorized by the minerals included, its Chemical compound, chemical composition, and the way in which it is formed. Rocks form the Earth's outer solid layer, the Earth's crust, crust, and most of its interior, except for the liquid Earth's outer core, outer core and pockets of magma in the asthenosphere. The study of rocks involves multiple subdisciplines of geology, including petrology and mineralogy. It may be limited to rocks found on Earth, or it may include planetary geology that studies the rocks of other celestial objects. Rocks are usually grouped into three main groups: igneous rocks, sedimentary rocks and metamorphic rocks. Igneous rocks are formed when magma cools in the Earth's crust, or lava cools on the ground surface or the seabed. Sedimentary rocks are formed by diagenesis and lithification of sediments, which in turn are formed by the weathe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Human History
Human history or world history is the record of humankind from prehistory to the present. Early modern human, Modern humans evolved in Africa around 300,000 years ago and initially lived as hunter-gatherers. They Early expansions of hominins out of Africa, migrated out of Africa during the Last Ice Age and had spread across Earth's continental land except Antarctica by the end of the Ice Age 12,000 years ago. Soon afterward, the Neolithic Revolution in West Asia brought the first systematic Agriculture, husbandry of plants and animals, and saw many humans transition from a nomadic life to a Sedentism, sedentary existence as farmers in Civilization, permanent settlements. The growing complexity of human societies necessitated systems of accounting and writing. These developments paved the way for the Cradle of civilization, emergence of early civilizations in Mesopotamia, Ancient Egypt, Egypt, the Indus Valley, and History of China, China, marking the beginning of the ancient ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Terminal Ballistics
Terminal ballistics is a sub-field of ballistics concerned with the behavior and effects of a projectile when it hits and transfers its energy to a target. This field is usually cited in forensic ballistics. Bullet design (as well as the velocity of impact) largely determines the effectiveness of penetration. General The concept of terminal ballistics can be applied to any projectile striking a target. Much of the topic specifically regards the effects of small arms fire striking live targets, and a projectile's ability to incapacitate or eliminate a target. Common factors include bullet mass, composition, velocity, and shape. Firearm projectiles Class of projectile Projectiles are primarily designed for compatibility with the constraints of the device used to launch them, and secondarily according to some balance of logistical practicality, practicable accuracy, and terminal effect. Prior to the development of rifling, the majority of projectiles purpose-built for shooting ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
