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Technology
Thermobaric weapons
They're gaining cachet with large military forces, but what exactly are they?
September 14, 2007
By Peter Nowak, CBC News
What is a thermobaric weapon?
A thermobaric weapon disperses a fine cloud of particles of a solid or an explosive liquid, then detonates the cloud with a charge. The result is an explosion of heat and pressure, essentially a fiery shockwave. Such weapons are often synonymous with fuel air explosives, with differences between the two mainly stemming from how quickly the explosive cloud is detonated. Throwing an aerosol spray can into a fire would achieve the same explosive effect as a thermobaric weapon achieves, although obviously on a much smaller scale.
What does thermobaric mean?
The term comes from Greek, with therme meaning heat and baros meaning pressure.
What are the substances used in these weapons?
Finely powdered aluminum and magnesium are the materials of choice.
Where did these weapons originate?
Some historians believe the flamethrower, which dates to the 19th century, was the first thermobaric weapon. While early Greek and Roman versions of the weapon used hand-pumped ignited oil, it was the German military that first developed pressure-propelled flamethrowers during the First World War. The German flamethrowers were used to attack trenches and bunkers.
What forms do thermobaric weapons come in?
The weapons range in size. In one of its smallest versions, a thermobaric weapon can be fired from a rocket-propelled grenade launcher as a shell. In its largest form, it can be dropped from a plane as a bomb. The Russian military detonated such a bomb this week and said it was the biggest and most powerful thermobaric weapon developed to date, capable of levelling several apartment buildings.
How powerful was the Russian bomb?
According to the Russian military, the bomb tested this week was the most powerful non-nuclear weapon ever exploded. It contained about seven tonnes of high explosives with a blast radius of about 300 metres, making it four times more powerful than a similar bomb developed by the United States. The U.S. military first tested its bomb, officially named the Massive Ordnance Air Burst and unofficially nicknamed the Mother of All Bombs, in 2003. The Russian media dubbed Moscow's new weapon the "Father of All Bombs." The U.S. bomb has a destructive force equivalent to 10 tonnes of TNT, while Russia says its bomb is equivalent to 40 tonnes.
What effect do the weapons have?
At the centre of an explosion, pressures of 30 kilograms per square centimetre, or 427 pounds per square inch, have been recorded. Normal pressure at sea level is 14.7 pounds per square inch, so people caught in the blast are crushed to death. The blasts have also been recorded to reach temperatures of 3,000 degrees Celsius.
What do these bombs look like?
The U.S. MOAB is about the length of a semi-truck, is bright orange and weighs 9,500 kilograms. Russia has not yet disclosed detailed information on its bomb, but it is green and appears to be around the same size as its U.S. counterpart.
Why are thermobaric weapons gaining cachet with U.S. and Russian military forces?
The two countries say such bombs are capable of massive destruction yet do not harm the environment as nuclear weapons do. They are also useful for attacking underground and hidden targets because the explosive blast can spread through tunnels. While a deeply buried target may be immune to traditional bombs, a thermobaric weapon can penetrate through a tunnel system and damage any equipment or systems, thus effectively neutralizing — if not actually destroying — the target.
How are these weapons being used?
The U.S. military tested its MOAB for use in mountainous regions of Afghanistan, where it was believed al-Qaeda leader Osama bin Laden was hiding, and it has said a variety of the weapons have been "highly effective" in Iraq. The Russian military is said to have developed its bomb for use in Chechnya. Russian soldiers previously used smaller weapons there, from 500-kilogram bombs to rocket-propelled grenade-launched shells.
Who else uses them?
China and India are also known to possess thermobaric weapons.
How do these weapons figure into international treaties and what do rights organizations say about them?
Human Rights Watch objects to the weapons and says they have the potential to "kill and injure in a particularly brutal manner over a wide area." Russia says the bomb it tested does not violate any of the international agreements it has signed. The Arms Control Association says there are no treaties that prevent the development of thermobaric weapons, although they could conceivably fall under a protocol of the Convention on Conventional Weapons, which prohibits incendiary weapons.
