This is a very strong bomb. 

This is a special kind of bomb. 

A thermobaric weapon is a special kind of explosive. 
Most bombs use a mix of fuel and an oxidizer. An oxidizer is a substance that helps things burn. Thermobaric weapons are different. They use only fuel. They get their oxygen from the air around them. This makes them very powerful for their weight.
These weapons work in a few steps. First, a small charge hits the target. This opens the container. It lets the fuel spray out as a cloud. This cloud can flow into tunnels or buildings. 
As the gases cool, the pressure drops fast. This can create a partial vacuum. 
A thermobaric weapon is a special type of explosive munition. You might hear people call them aerosol bombs or vacuum bombs. The name thermobaric comes from two Greek words. The word "thermos" means hot. The word "baros" means weight or pressure. These weapons are very different from regular explosives. Most normal explosives use a mix of fuel and an oxidizer. An oxidizer is a substance that helps things burn. Thermobaric weapons only use fuel. They get their oxygen from the air around them. This makes them much more energetic than regular explosives of the same weight. 
These weapons work through a specific way it works. First, a small explosive charge hits the target. This charge breaks open the container. It spreads the fuel out as a large cloud. This cloud can flow around objects and into buildings. The fuel can be a gas, a liquid, or even a powder. Some fuels use metal powders like aluminum or magnesium. After the cloud forms, a second charge sets it on fire. This creates a massive blast wave. This wave lasts much longer than a normal explosion. The flame front grows to a huge volume. This creates pressure in the fuel and the surrounding air. 
People have been trying to make these weapons for a long time. During World War I, Germans used incendiary shells. These used tar and gunpowder dust to burn for two minutes. In World War II, a physicist named Mario Zippermayr led work on these weapons for the German Wehrmacht. Later, the United States developed fuel-air explosives for the Vietnam War. The US Naval Weapons Center at China Lake helped develop the CBU-55 bomb. After the US started using them, Soviet scientists also made their own versions. Today, many different countries have developed their own types of these weapons. 
There are many specific types of these weapons used today. The US uses the BLU-73 and the BLU-95. They also use the XM1060 grenade in places like Afghanistan. The US Marine Corps uses a round called the SMAW-NE. In Russia, soldiers use the RPO-A rocket. There is also a pump-action launcher called the GM-94. This grenade weighs 1.5 kilograms and has a lethality radius of 15 meters. Another Russian tool is the TOS-1, which is a vehicle with 24 tubes. It can cover a large rectangle with its rockets. Some missiles, like the Kornet, can even carry these warheads. 
These weapons are very effective in enclosed spaces. This includes places like tunnels, bunkers, caves, and foxholes. The blast wave can destroy strong buildings and heavy equipment. Because the cloud flows into spaces, it is hard to hide from. Regular protection like sandbags or armor does not work well against them. As the gases cool, the pressure drops very quickly. This creates a partial vacuum, which is why they are called vacuum bombs. This sudden change in pressure can be very dangerous. 
A thermobaric weapon is a specialized type of explosive munition. These weapons are often called aerosol bombs or vacuum bombs. The name "thermobaric" comes from two Greek words. "Thermos" means hot, and "baros" means weight or pressure. Unlike conventional explosives, which use a pre-mixed fuel and oxidizer, thermobaric weapons use only fuel. They rely on the oxygen found in the surrounding atmosphere to complete the chemical combustion. Because they do not carry their own oxidizer, they can be significantly more energetic than standard explosives of the same weight. 
The mechanism of a thermobaric weapon involves a two-step process. First, an initial explosive charge, known as a scatter charge, detonates upon impact. This charge breaks open the munition's container and disperses the fuel as a large aerosol cloud. This cloud can consist of gas, liquid, or even powdered materials. The fuel might be organic materials or powdered metals like magnesium or aluminum. This cloud is capable of flowing around obstacles and into enclosed structures. 
Once the fuel is dispersed, a second charge ignites the cloud. This creates a massive, sustained blast wave. In a conventional explosion, the blast comes from a single point. In a thermobaric explosion, the flame front accelerates to a massive volume. This creates pressure fronts within both the fuel mixture and the surrounding air. The blast wave often lasts much longer than a typical explosion. In some confined settings, reflective shock waves can extend the fireball's duration to between 10 and 50 milliseconds. As the gases cool, the pressure drops sharply. This creates a partial vacuum, which is the reason for the name "vacuum bomb."
Thermobaric weapons are most effective in enclosed or semi-enclosed spaces. This includes tunnels, buildings, bunkers, caves, and foxholes. The fuel cloud can seep into these areas before the ignition occurs. Because of this, traditional countermeasures like sandbags or personal armor are often ineffective. A study by the US Central Intelligence Agency suggested a unique danger to people in these areas. The shock and pressure waves might cause minimal damage to brain tissue. This could mean victims are not knocked unconscious but instead suffer from suffocation for several minutes. 
The history of these weapons began with early German attempts. During World War I, incendiary shells used tar-impregnated tissue and gunpowder dust. These shells could burn for about two minutes. In World War II, the physicist Mario Zippermayr directed research into these weapons for the German Wehrmacht. Later, the United States developed fuel-air explosives (FAE) for use during the Vietnam War. The US Naval Weapons Center at China Lake was involved in developing the CBU-55 cluster bomb. Following these developments, Soviet scientists also created their own versions of FAE technology.
Modern technology has produced many different types of these munitions. The United States uses various models, including the BLU-73 and the BLU-95. They also use the XM1060 40-mm grenade, which was used in Afghanistan to target caves. The US Marine Corps uses the SMAW-NE, a "Novel Explosive" round for the Mk 153 SMAW launcher. Russia has also developed a wide array of third-generation warheads. For example, the RPO-A is an infantry-portable rocket. The GM-94 is a pump-action grenade launcher that fires a 1.5-kilogram grenade. This grenade has a lethality radius of 15 meters. 
Advanced systems provide even greater scale and range. The Russian TOS-1 is a dedicated vehicle with 24 launch tubes. A single full salvo from this system can cover a large rectangular area. Other sophisticated tools include the RShG-1, which is a powerful variant of the RPG-27. The RMG uses a tandem-charge system. This features a high-explosive anti-tank warhead that blasts an opening for the thermobaric charge to enter. Some anti-tank missiles, like the Kornet, also feature thermobaric variants. The Kornet-EM can reach a maximum range of 5.5 kilometers. 
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