Bulletproof vest
A bullet-proof vest , also bullet-resistant vest , (ballistic) protective vest , Flakweste , colloquially bulletproof vest , bulletproof vest or after their material Kevlar vest called, serves to protect the wearer from the deadly effects of small arms projectiles and / or before shrapnel to protect and only Equipped with a stab-resistant plate also in front of stabbing and cutting weapons.
Development history
Protective vests are one of the protective weapons , the early development of which goes back to armaments made of various materials. Body armor, which offered the wearer protection against the effects of violence from cut, stabbing or projectile weapons, were already manufactured in antiquity. The earliest preserved bronze tanks date back to the 14th century BC. Dated, later pieces were made of steel. The first lamellar armor and scale armor , which offered more mobility compared to armor plates, are already known from China from this time. Early fiber composite armor can be found in the linen armor of ancient Greece. In the Middle Ages came Gambeson on. In the 4th century BC The ring armor that emerged in BC was used with modifications until the 20th century.
Contrary to popular belief, steel plate armor , such as those produced in Europe from the 14th century, were extremely effective at protecting against projectiles from both conventional bow and firearms. At the beginning of the 19th century, for example, Napoleon had breast and back armor made especially for his cuirassiers . The US Civil War Vest was used by the Union Army in the mid-19th century .
A well-known plate armor, the Ned Kelly armor , was used by Ned Kelly around 1880 .
The physician George E. Goodfellow (1855-1910) practiced in Tombstone in the final phase of the " Wild West ". He came into contact with many gunshot wounds , so he autopsied the victims of the shooting at the OK Corral . Goodfellow noticed that silk scarves , be it as a handkerchief or handkerchief , were not perforated by the projectiles. The energy of the impact often caused a life-threatening injury. Goodfellow published his observations in 1887. At the end of the 19th century, the Polish immigrant Casimir Zeglen developed a protective vest made of silk fibers in Chicago . However, it is unlikely that Zeglen was aware of Goodfellow's observations. Zeglen's vest provided effective protection against gunpowder- powered handguns with slow muzzle velocities , but failed with guns powered by nitrocellulose powder with higher muzzle velocities. Zeglen and Jan Szczepanik improved the fabric of the West. However, the material was very expensive. By 1914, Zeglen's vest cost around $ 800, which was about € 11,000 in 2011. Among the customers was the Spanish King Alfonso XIII. She helped survive a bomb attack.
It is often reported that the Austrian heir to the throne, Franz Ferdinand, wore a bullet-proof vest during the assassination attempt in Sarajevo , but this could not help him because the assassin's projectile hit Ferdinand's neck above the vest. However, it is not certain that Ferdinand even owned such a vest; under no circumstances did he wear them during the assassination attempt.
In the First World War , plate armor was used as protection against splinters and fire. In the 1930s, modern ballistic vests were tested by the Berlin police . The Soviet SN-42 , also a plate armor, is known from the Second World War .
In the second half of the 20th century, the development of protective vests made significant progress due to new materials. Advances in the development of new materials mean that a further increase in the protective effect of soft and hard ballistic protective vests appears likely in the near future. Here, for example, they reported on rayon and nanotechnology , including a composite material made of tungsten disulfide , which, according to the manufacturer, should withstand up to 250 tons per square centimeter. In return, however, an attacker can also use a larger caliber, armor-piercing ammunition , a stronger cartridge load or, if necessary, a new type of weapon.
American Civil War Protective Vest (1861-1865)
Splinter protection half-shell and M1916 steel helmet from the First World War
Soviet soldier with armor made of 2 mm armor plates (1942)
US soldier with flak jacket in Vietnam (1971)
The US Army's Improved Outer Tactical Vest (IOTV) since 2007
function
A bullet-resistant vest is designed to prevent a bullet from penetrating . The kinetic energy of the projectile is absorbed and distributed over the largest possible area. The bullet itself remains in the body of the vest, but can deform it. The impulse of the bullet is passed on to the wearer of the protective vest. Both lead to blunt trauma . Thus, protective vests do not make “bulletproof”, but protect the wearer from the lethal effect of projectiles up to the specified degree of protection.
Protection classes
The protective power of a vest is indicated with the so-called protection class. Several standards have been established here worldwide. In order to verify ballistic protection, several samples are subjected to a material test. The protection classes depend on the environmental conditions, number of test shots, caliber and bullet speed.
The most important standard is the BA 9000 , a quality management system for body armor, which was introduced in 2012 as an NIJ standard by the American National Institute of Justice , the research center of the Justice Department . Every authority or organization with such a need usually conducts its own fire tests according to its own requirements, as do the various armed forces. In Germany, the bullet test is carried out by the state firing offices according to the technical guidelines for protective vests of the police .
The type of base on which the protective equipment for the fire test is attached is also decisive for the outcome of the test. When attached to a hard surface, it is more easily penetrated than in practice, as the human tissue gives way and the protective equipment can form a dent. In order to simulate this, the modeling clay "Roma Plastilina" is usually used. This material is somewhat harder and less elastic than human tissue, but has the advantage that the dent caused by the impact of the projectile does not return to its original state. In this way, physical damage can be estimated that would occur even if the body protection equipment intercepts the projectile.
At the end of a bullet test, a piece of personal protective equipment is certified as having a certain protective effect. Whether this is constant in the entire production and how long it remains for the personal protective equipment is a matter for the manufacturer and the customer and must be tested by long-term tests and repeated checks of production copies. Most manufacturers guarantee the protective effect of their products for five or ten years.
The German and American protection classes are not easily transferable, although the calibres used are similar. The general conditions differ significantly. American samples are shot only once, but German samples three times, and the environmental conditions also differ. Nevertheless, the German protection class (SK) 1 is generally equated with the American NIJ level IIIA. Both define protection against common handguns , although the calibers used are similar. The German SK4 and NIJ Levels III and IV are also often compared. They define protection against fire from long guns .
The essential protection classes are:
- SK 1 and Level IIIA
- Protection against handgun ammunition with a soft core and round head or partial jacket or hollow point
- SK 2
- Protection against handgun ammunition with a hard core
- SK3 and Level III
- Protection against rifle ammunition with full jacket and soft core or partial jacket or hollow point
- SK4 and Level IV
- Protection against rifle ammunition with full jacket and hard core
Protection against stab weapons such as knives or needles, also known as stab protection , is not necessarily included in the first two protection classes and must be provided additionally. In the case of protective vests of protection classes 3 and 4, on the other hand, stab protection is also required in terms of design through ballistic plates. Protective vests of the respective class can, however, be penetrated by special projectiles with a penetrator or by ammunition with a higher projectile speed.
construction
Protective vests are made from different materials according to different construction principles. A general distinction is made between hard and soft ballistics. Certain protective effects can usually only be achieved by combining both principles. All-round protection according to protection class 1 can be achieved with a soft ballistic vest. Additional hard ballistic inserts on the front and back as well as on the sides guarantee protection according to protection class 4. Most protective vests are constructed in this combination. The hard ballistic plates used then only achieve their protective effect in combination with the soft ballistic vest body.
Protective vests differ not only in their protective effect, but also in the protected body area. Most vests only protect the areas of the body with the largest area and thus the greatest chance of being hit, mostly the torso . Depending on the type of vest, additional protectors can also protect the sides of the body, genital area, shoulders, neck, arms and legs. However, this protection limits the mobility of the wearer. Further differences arise from the construction of the vest body. In order to wear the ballistic protective inserts on the body and to protect them from damage in everyday use, they are sewn into protective vest covers made of heavy-duty textiles. These can then also offer attachment options for equipment with MOLLE loops or also enable concealed carrying, for example by matching the color to the rest of the clothing.
Soft ballistics
The bullet hits a multi-layer net or foil structure made of tear-resistant fabric. The bullet energy is partially absorbed when the bullet sets the individual layers in motion in the direction of the bullet ( acceleration work ) and stretches the fibers ( tension work ). Most of the energy is still retained. The projectile forms a bulge in the shape of a truncated cone on the side of the tear-resistant fabric facing the body until the projectile and the body tissue hit move at the same speed ( inelastic shock ). Bulletproof clothing is considered unsuitable not only if the soft ballistic fabric is pierced by the projectile, but also if the penetration cone into the body is too deep. This is tested on a human body modeled from special modeling clay.
At the beginning of the twentieth century, protective vests made of silk fibers were developed. The very high price prevented mass use until aramid fiber fabrics became a viable and affordable replacement.
Today aramid fibers are mostly used under trade names like Twaron or Kevlar or other plastics such as PBO ( Zylon ) and highly crystalline polyethylene ( Dyneema ). These plastics are extremely tear-resistant, but lose their properties with the aging process. This takes place - depending on the material - over several years and is accelerated by the action of UV light . Moisture also usually leads to poorer properties. For these reasons, soft ballistic protective inserts of protective vests are welded into plastic film.
Theoretically, any floor can be stopped with a suitable number of layers. For practical reasons, however, soft ballistic protective inserts are only made to protect against handgun projectiles. In addition, pure fiber fabrics do not offer sufficient stab protection .
Hard ballistics
Here the bullet hits a plate made of a hard material and distributes its kinetic energy to it. The kinetic energy is absorbed by the plate and leads to deformations. The principle has been used in armaments for a long time. Metals (ballistic steel) have been used here for centuries, recently also oxide ceramic or polyethylene plates. Modern hard ballistic protection plates are made from a combination of different materials according to a layer principle and have a curve shape to better absorb the impact energy, but also to adapt to the body shape of the wearer. Theoretically, plates can be used to stop all types of projectiles, depending on the material thickness. For the reasons mentioned above, most protective plates only achieve their full protective effect in combination with soft ballistic protective packages.
The US military , as the world's largest purchaser of hard ballistic body protection plates, has ensured a certain standardization in the design. Most of the plates are 10 " × 12" (25.4 cm × 30.5 cm) in size with beveled upper corners and are then referred to as (E) SAPI plates ("Small Arms Protective Insert"). However, other plate shapes are also produced. Ensuring complete all-round protection with hard ballistic materials has long been considered impractical due to the weight of these protective inserts. Purely hard ballistic protective vests were therefore mostly implemented in the form of so-called plate carriers . Here only the front and back are protected with so-called stand-alone panels. These special plates can stop bullets even without an underlying soft ballistic protective package, but they are heavier.
Another approach is body armor, which is composed of numerous small elements like scale armor. The Red Army used such vests with titanium scales in the 1980s. Today, similar body armor with steel and silicon carbide inlays as Dragon Skin Body Armor is only produced by an American company. The advantage of this concept is the deformability of the ballistic inserts, which enables a larger area of the upper body to be protected and the wearer to move with less energy. In addition, despite its low weight, it has a better protective effect, since the body protection can be hit more often by hard ballistic materials without losing its effect.
Stab protection
When it comes to stab protection, the special mode of action of stab weapons must be observed. These can have a cutting, displacing or punching effect. A long cut with a knife can possibly be stopped by light protective fabrics. A stab with a needle will penetrate the body of a soft ballistic protective vest. In order to protect the wearer against stabbing weapons, additional inlays made of metal foils and interwoven metal rings are used in the lighter protective vests. The foils protect against particularly sharp objects with a punching effect, e.g. B. needles or cannulas of syringes. The interwoven metal rings, whose effect resembles a chain mail, are intended to counteract the displacing effect of knife blades or axes. In the hard ballistic protective inserts of the vests with protection classes 3 and 4, on the other hand, stab protection is already guaranteed by the plates. Since these systems usually only cover the front and back, the stab protection on the sides of the body may have to be additionally covered with the above. Funds are supplemented.
Impact protection
Impact protection is not the direct task of a ballistic protective vest. Since the extremities and the head in particular have to be protected here, additional protectors and a helmet are necessary. These usually consist of plastics and are lined with upholstery fabrics. Such protectors usually have no ballistic protection, but are often part of the stab protection. The vests used in body protection equipment do not necessarily have to have a ballistic protective effect. The integration of a ballistic protective vest in body protection equipment is entirely possible.
application
There are civil as well as military areas of application for ballistic protective vests. People who are at increased risk, such as police officers, public figures or others, have a higher chance of survival in the event of an attack. The German police have now introduced protective under vests across the board: concealed protective vests of SK 1, which in some police forces (e.g. Hesse , Baden-Württemberg or the federal police ) can be worn with a tactical cover over outer clothing. For operations that are recognizable in advance, there are protective vests that cover a larger area of the body, can be expanded with additional protectors and their protection class can be adjusted. Ordnance clearers usually wear full protective suits that only leave their hands free. Hundreds of riot police usually do not wear ballistic vests, but punch and stab vests. In the German Federal Armed Forces , soldiers deployed abroad are equipped with SK 4 protective vests. There are no restrictions on the purchase of protective vests in Germany. Worldwide there are different regulations regarding the possession of protective vests. In some countries, private persons are prohibited from possessing or carrying, and in some cases also importing them. In addition, export restrictions usually apply . There are protective vests for service dogs and hunting dogs .
Limitations and disadvantages
Bullet-resistant vests are by no means "bulletproof". As described, there is no guarantee that the wearer will not suffer internal injuries such as broken bones or bruises in spite of a protective vest . It is also still possible for bullets to penetrate the vest if the protective effect is insufficient. Bullets with a soft jacket material are usually already mushroomed or fragmented and suddenly give off their residual energy to the wearer's body, which can lead to large and deep wounds. It is also possible that when the vest is perforated, parts of the protective packages, splinters of the ballistic plates and the material of the cover penetrate into the wound canal. Even if the projectile does not penetrate the vest, the impulse of a sufficiently heavy and fast projectile transmitted to the body can injure the internal organs and thus lead to death without visible external injury.
Furthermore, only a few vests offer complete protection, so that bullets can still injure extremities and through the openings, for example for the arms, can still penetrate the actually protected area of the body. Bottom vests, for example, offer their best protection when they are worn under uniform. If it is worn incorrectly (e.g. over the uniform), a transmission pulse will occur in the event of a bullet impact. This puts pressure on buttons, pens, etc., which can lead to serious injuries.
Another problem is the aging process described, which can reduce the protective effect of the protection packages. The case of the material Zylon from the Japanese company Toyobo should be mentioned here. With this material, particularly light protective vests seemed feasible at the end of the 1990s. During the long-term testing, however, it turned out that this material aged particularly quickly and lost its protective effect after just three years. The manufacturing company that supplied the police in Bavaria and North Rhine-Westphalia with vests made from this material went bankrupt due to the subsequent claims for damages.
Improper handling, such as incorrectly putting on or damage to the protective vest, can also reduce the protective effect. For example, before the Battle of Mogadishu , the US soldiers removed the rear panel from the protective vest to increase its mobility. In soldiers who were shot in the back, the front plate not only prevented the projectile (mostly in the 7.62 × 39 mm caliber ) from coming out of the body again, but the projectile ricocheted off the plate and was restored transported back into the body. This resulted in further injuries and may have killed some soldiers.
Further disadvantages are the fact that the vest body restricts the body's perspiration and can possibly lead to heat build-up, as well as the weight. Protective vests weigh between a few kilograms and 30 kg, depending on the protection class and size. Protective vests are also a psychological protection that gives a person a feeling of security in a dangerous environment, but also repeatedly leads to an overestimation of the protective effect of this equipment.
In some countries, protective vests may not be imported or only with a prior customs permit, as they are considered war equipment.
See also
- Target ballistics and wound ballistics deal with the behavior of projectiles when they hit a target
- Interceptor Body Armor is a protective vest used by the American armed forces
- Lamellar armor as a modern version of protective vests that adapt to the body
- CRISAT ( Collaborative Research Into Small Arms Technology )
literature
- Stephan Restle: Ballistic protective vests and stab protection options. Kabinett Verlag, Bischofszell 1997, ISBN 3-906572-03-X .
- Association of test centers for attack-resistant materials and constructions (VPAM) (publisher): Test guideline "Stab and impact protection". Status: May 18, 2011 ( PDF; 185.37 kB ). Retrieved December 23, 2013.
Web links
- A picture and its story: Shoot! Solveig Grothe on the development of bulletproof vests in the USA. Spiegel Online from August 29, 2017, accessed on February 13, 2020.
Individual evidence
- ↑ a b c Martin J. Brayley : Modern Body Armor , 2011, Crowood Press, ISBN 978-1847972484 , p. 6
- ↑ John K. Lee: Bulletproof Silk: Observations of Dr George E. Goodfellow, the Gunfighter's Surgeon in: The Journal of the American Osteopathic Association November 2016, Vol. 116, No. 11 ( online )
- ↑ George E. Goodfellow: Notes on the impenetrability of silk to bullets in: The Southern California practitioner , March 1887, Vol. 2, No. 2, pp. 95-98 ( online )
- ↑ Sławomir Łotysz : Tailored to the Times: The Story of Casimir Zeglen's Silk Bullet-Proof Vest. In: Arms & Armor , Vol. 11 No. 2, autumn 2014, pp. 164–186 ( online )
- ↑ Sławomir Łotysz: Tailored to the Times: The Story of Casimir Zeglen's Silk Bullet-Proof Vest. In: Arms & Armor , Vol. 11 No. 2, autumn 2014 ( online )
- ^ Sara Malm: Could this bullet-proof vest have changed history? In: Daily Mail , August 3, 2014
- ↑ Maev Kennedy: Tests prove did a bulletproof vest silk Could have stopped the first world war. In: The Guardian , July 29, 2014
- ↑ NIJ portal: Body Armor ( Memento of 9 January 2010 at the Internet Archive )
- ↑ Technical Guideline "Ballistic Protective Vests". ( Memento from March 22, 2013 in the Internet Archive ) In: pfa.nrw.de (PDF)
- ↑ Lisa Traynor: The Archduke and the Bullet-Proof Vest: 19th-Century Innovation Versus 20th-Century Firepower. In: Arms & Armor , Vol. 11 No. 2, autumn 2014 ( online )
- ↑ Ashok Bhatnagar: Lightweight Ballistic Composites: Military and Law-Enforcement Applications , Woodhead Publishing, 2016, ISBN 9780081004258 , pp. 122–123 ( online )
- ↑ mvs.de ( Memento from September 28, 2007 in the Internet Archive ) Mehler VarioSystems:
- ↑ Dragon Skin® from Pinnacle Armor
- ↑ dailynightly.msnbc.com ( Memento of March 4, 2016 in the Internet Archive ) Lisa Myers report
- ↑ PTIOnline ( Memento from May 22, 2013 in the Internet Archive )
- ↑ PTIOnline ( Memento from May 22, 2013 in the Internet Archive )
- ^ Hunters' Association Northeim: First aid for hunting dogs
- ↑ Hells Angel shoots police officers despite a protective vest. In: Abendblatt.de , March 18, 2010, accessed on January 7, 2018
- ↑ GdP: ( Memento from August 16, 2010 in the Internet Archive )
- ↑ Jörg Diehl: Police protective vests with holes in the lifesaver. In: spiegel.de , April 18, 2005, accessed on January 7, 2018
- ↑ Clifford E. Day: Critical analysis on the defeat of task force ranger, (online PDF 175 kB) ( Memento from September 30, 2019 in the Internet Archive ), document no. "AU / ACSC / 0364 / 97-03", Biblioscholar, 2012, ISBN 1-249-84225-5 , page 32.