A camouflet, in
military science, is an artificial
cave
A cave or cavern is a natural void in the ground, specifically a space large enough for a human to enter. Caves often form by the weathering of rock and often extend deep underground. The word ''cave'' can refer to smaller openings such as sea ...
rn created by an
explosion
An explosion is a rapid expansion in volume associated with an extreme outward release of energy, usually with the generation of high temperatures and release of high-pressure gases. Supersonic explosions created by high explosives are kno ...
. If the explosion reaches the surface then it is called a
crater.
The term was originally defined as a countermine dug by defenders to prevent the
undermining of a fortress's walls during a
siege
A siege is a military blockade of a city, or fortress, with the intent of conquering by attrition, or a well-prepared assault. This derives from la, sedere, lit=to sit. Siege warfare is a form of constant, low-intensity conflict characterize ...
. The defenders would dig a tunnel under the attackers' tunnel. An
explosive
An explosive (or explosive material) is a reactive substance that contains a great amount of potential energy that can produce an explosion if released suddenly, usually accompanied by the production of light, heat, sound, and pressure. An exp ...
charge would be detonated to create a camouflet that would collapse the attackers' tunnel.
More recently, the term has been used to describe the effects of very large bombs like the
Grand Slam bomb, which are designed to penetrate next to a large target structure and create a camouflet to undermine the foundations of the structure. It has been observed that it is more efficient to penetrate ground next to the target than to hit the target directly.
A camouflet set describes a system used in the
British Army
The British Army is the principal land warfare force of the United Kingdom, a part of the British Armed Forces along with the Royal Navy and the Royal Air Force. , the British Army comprises 79,380 regular full-time personnel, 4,090 Gur ...
for cratering tracks and other routes. A tube is driven into the ground using a manual post driver. The end of the tube is a disposable steel point. A small charge connected to a detonator is lowered down the tube. The tube is then removed, and the hole tamped. The charge is then blown, leaving a void and a hole to the surface. This void is then filled with a much larger charge, which is also tamped, and then blown when required to create a crater as an obstacle. A refinement was introduced in the 1980s, with the use of a
shaped charge
A shaped charge is an explosive charge shaped to form an explosively formed penetrator (EFP) to focus the effect of the explosive's energy. Different types of shaped charges are used for various purposes such as cutting and forming metal, init ...
to create the initial hole.
Because of the presence of high levels of toxic fumes from the explosive, including
carbon monoxide
Carbon monoxide ( chemical formula CO) is a colorless, poisonous, odorless, tasteless, flammable gas that is slightly less dense than air. Carbon monoxide consists of one carbon atom and one oxygen atom connected by a triple bond. It is the si ...
, and the weakness of the soft earth overlying the cavern, camouflets are extremely hazardous to
bomb disposal
Bomb disposal is an explosives engineering profession using the process by which hazardous explosive devices are rendered safe. ''Bomb disposal'' is an all-encompassing term to describe the separate, but interrelated functions in the militar ...
personnel.
See also
*
Canadian pipe mine
References
{{reflist
Siege tactics
Military engineering
Military strategy
Bomb disposal
Strategic bombing