One of the more advanced properties of being an explosives specialist is the capability to set off an explosive device exactly when it is required to detonate. Hypothetically speaking a time bomb could be setup to explode after four months during a change in season during which time the perpetrator could disappear with very little evidence associating him with the device. The science of time bombs is much more complicated than the use of conventional explosives. i.e anyone could put a fuse in a pipe bomb and blow it up but very few have the ability to control their explosions down to the minute or the second hours after the device has been deployed in its place.There are two types of technologies associated with time bombs; The electrical deals with the use of electronic circuits to time when the bomb will go off, this technology is very accurate and could be used to control an explosion down to the last second. The mechanical is the crude way of doing things, it is less precise but can be setup a lot easier than by using an electronic circuit. An additional technology is chemical which will also be discussed.
Fire plays a very important role in mechanical timed explosions. The very simple example is the cigarette; a cigarette burning itself out also has a moving flame, a fuse can be tied at the base of the cigarette where the flame ends up and this fuse has a good chance of being lit once the cigarette reaches that point. However with safety technology being applied to cigarettes it is very likely this will not work very well, even if the filter is removed to aid an air draft the heat of the cigarette will find difficulty in lighting the fuse. A much better alternative is to use a candle, simply a long candle placed flat on a non flammable surface with a fuse intersecting it at it’s base where it will ignite once the flame reaches the fuse. A cigarette can usually take four minutes to burn out and candle time varies from one type to another.
Probably the best overall type of time bomb technology. The easiest way to use this is to buy a time delay relay circuit from an electronics shop. The relay controls the connection between a battery and the detonator and the circuit controls the circuit. So if the circuit is set for one hour once the hour is up the relay closes connecting the battery to the electrical detonator causing an explosion. Only a basic knowledge of hobby electronics is required for use of a prebuilt relay delay circuit. A technician could also build a special purpose electrical circuit to this purpose including safety devices and indicators to prevent accidents. An electromechanical time bomb can be build using an analogue clock or watch; A small nail can be punched into the face and when the minute or hour hand contact the nail a circuit is closed between the axis of the clock and the nail which when are attached to wires, battery and detonators can be an effective and easy to contstruct time bomb.
Chemical delay initiators are very interesting and have their own special uses. Once being they cannot be easily detected by electronic equipment since they don’t use a battery or emit any radiation and they are also easily destroyed with the explosion preventing a forensics team from identifying the initiator. The reaction between Perchlorate or chlorate and sulphuric acid is explosive. if sulphuric acid is set to drip on aluminium foil it will eventually eat through the foil and could be setup to drip on chlorate powder on the other side causing an explosion on contact. Permanganate and Glycerol also form an interesting combination, once glycerol liquid is in contact with Pottassium Permanganate there is a delay of three minutes before the compound bursts into flame.
This device is extremely dangerous and should not be attempted.
This article is provided for information purposes only.