A tilt fuze or fuse is a device usually used in the operation of

car bomb A car bomb, bus bomb, lorry bomb, or truck bomb, also known as a vehicle-borne improvised explosive device (VBIED), is an improvised explosive device designed to be detonated in an automobile or other vehicles. Car bombs can be roughly divided ...

s and other such

detonator A detonator, frequently a blasting cap, is a device used to trigger an explosive device. Detonators can be chemically, mechanically, or electrically initiated, the last two being the most common. The commercial use of explosives uses electri ...

s, relying on the force of a jerk or similar movement for the triggering of the desired explosion.Wilkinson p. 137 The tilt fuze is typically a home-made

mercury switch A mercury switch is an electrical switch that opens and closes a circuit when a small amount of the liquid metal mercury connects metal electrodes to close the circuit. There are several different basic designs (tilt, displacement, radial, etc. ...

. It consists of a small tube no larger than a medical tablet bottle, made from plastic, glass or some other such material. At the bottom end of the tube, a certain volume of

mercury Mercury commonly refers to: * Mercury (planet), the nearest planet to the Sun * Mercury (element), a metallic chemical element with the symbol Hg * Mercury (mythology), a Roman god Mercury or The Mercury may also refer to: Companies * Merc ...

is placed, while at the cap end are wired two

live Live may refer to: Arts, entertainment, and media Films * ''Live!'' (2007 film), 2007 American film * ''Live'' (2014 film), a 2014 Japanese film *'' ''Live'' (Apocalyptica DVD) Music *Live (band), American alternative rock band * List of albums ...

electrical contacts linked to a battery and bomb.Cutterbuck (1994) p. 52 This apparatus is then fixed lengthwise to the target vehicle; most usually, the tube is attached to the underside, below the driver or passenger's seat (depending on the desired target and the strength and quantity of the detonators) or within the

mudguard A mudflap or mud guard is used in combination with the vehicle fender to protect the vehicle, passengers, other vehicles, and pedestrians from mud and other flying debris thrown into the air by the rotating tire. A mudflap is typically made fro ...

s. The function of the fuze is such that when it is tilted or moved, the mercury – a liquid metal – will slide down the tube and close the electrical circuit wired to the bomb. Once the circuit is closed, the

electric current An electric current is a stream of charged particles, such as electrons or ions, moving through an electrical conductor or space. It is measured as the net rate of flow of electric charge through a surface or into a control volume. The moving pa ...

will then be able to bridge the previously open gap and activate the bomb presumably concealed in another part of the vehicle. Such a tilting of the tilt fuze will likely occur over the regular bumps and jerks of the vehicle driving, ascension up the slope of a hill, or the depression of the brake or acceleration pedals, depending on the placement of the tube. Due to the volatility in the conduction of the operation, bombers often take precautionary measures to prevent accidental tilting of the fuze while they are setting up. These often include a timer incorporated with the electric current; the bomber may set a certain time period before the contacts become live, therefore ensuring that the bomb cannot be activated until the bomber is well clear of the area. Tilt fuzes sometimes meet use with the

anti-handling device An anti-handling device is an attachment to or an integral part of a landmine or other munition such as some fuze types found in general-purpose air-dropped bombs, cluster bombs and sea mines. It is designed to prevent tampering or disabling, o ...

s incorporated into munitions such as the

VS-50 mine The VS-50 is a circular plastic-cased anti-personnel blast mine that entered production in 1985. It was formerly made by the now-defunct Valsella Meccanotecnica SpA, an Italian high-tech defence company specialized in area denial systems. The com ...

. The

Luftwaffe The ''Luftwaffe'' () was the aerial-warfare branch of the German ''Wehrmacht'' before and during World War II. Germany's military air arms during World War I, the ''Luftstreitkräfte'' of the Imperial Army and the '' Marine-Fliegerabtei ...

World War II World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the vast majority of the world's countries—including all of the great powers—forming two opposin ...

are known to have made use of variants of the tilt fuze in their bomb fuzes. Tilt fuzes have been used extensively by the

Irish Republican Army The Irish Republican Army (IRA) is a name used by various paramilitary organisations in Ireland throughout the 20th and 21st centuries. Organisations by this name have been dedicated to irredentism through Irish republicanism, the belief tha ...

and

Irish National Liberation Army The Irish National Liberation Army (INLA, ga, Arm Saoirse Náisiúnta na hÉireann) is an Irish republican socialist paramilitary group formed on 10 December 1974, during the 30-year period of conflict known as "the Troubles". The group seek ...

since 1979.Clutterbuck (1990), p.181

Notes

References

* * * {{DEFAULTSORT:Tilt Fuze Improvised explosive devices Car bombs