In movies, whenever anyone has to disable a bomb, they have to remember
which color wires to cut. Are real bombs built this way? It would seem to
me that a slightly imaginative bomb maker could simply use different color
wires from the standard, foiling the hero’s plan.
I’m pretty sure it’s just a plot device. Wouldn’t simply locating the battery and disconnecting it be enough to defuse most bombs?
In the movies I’ve seen, the guy doing the wire cutting NEVER can remember which wire to cut, he just takes his chances. The reality of course is that there is no colour coded scheme for bomb making.Thats why sappers (bomb technicians) analyze the threat level of the device before deciding on whether to disarm it ,explode it in place, or move it to a bomb containment tank and detonate it there.
‘. Wouldn’t simply locating the battery and disconnecting it be
enough to defuse most bombs?’
Not if it has a detect low voltage switch, you know, like your smoke alarm does.
Not all bombs use electricity to detonate them. Some use chemical reactions like acids eating through a copper disc. Below that disc awaits a reactive agent which either heats up or explodes into the secondary and more powerful charge.
The bombs that do use electricity can be wired to detonate on movement or opening for inspection, by various types of switch mechanisms, Hence the reason to analyse them before taking a course of action to neutralize them.
Has there ever been a movie where the guy who anguishes over which wire to cut actually cuts the wrong one and detonates the bomb? I don’t think I’ve seen that.
I think if I were a terrorist(give it a little time) I would make all of the wires in my bombs red. Let’s see them diffuse THAT!
I think that was used in the first season finale of “Sledge Hammer.” It was a nuclear bomb Sledge (“Trust me. I know what I’m doing.”) was trying to disarm.
Riggs did it in LW3, also.
Watch your PBS stations for the next run of UXB. Disarming real bombs is not that fun. The bombs that guys are shown defusing by color code are ones that are mass produced (like aerial bombs) that need color codes so that the manufacturer does not mis-wire it to explode in a plane’s bomb bay. When the Germans recognized that the Brits were defusing a number of unexploded bombs in Britain, they started playing head games by changing the wiring of bombs for the expicit purpose of killing the bomb squad. (I have no reason to believe that the allies did not follow similar psychological warfare practices, but I have never seen that we did.)
Disarming a home-made bomb would require examining the actual wiring, regardless of wire colors.
[rant]My most hated of the movie bomb clichés is, “a mercury switch, we’re dealing with professionals here, probably CIA.” Auuuugh! Any dork who hangs around Radio Shack could easily use one to make a bomb defuse reistant or set the bomb off when the package is handled. Sometimes they even find the switch in the debris (Lethal Weapon). A mercury switch is a glass vial, one of the least likely things to survive a blast. [/rant]
I’ve a friend who was in the Army bomb disposal squad, mostly WWII stuff and his biggest headache was not the bomb going off but rather the collapse of the sides of the hole that usually has to be dug to get at the thing.
They usually lift them out cart them off and blow them on a range, sometimes though rarely they will steam out the explosive and leave the fusing mechanism alone.
Ironically the Germans have the worst problem from a disarming point of view. The stuff they dropped on us has fairly stable and better quality fuse mechanisms so they are more predictable unlike the less reliable and somewhat scary nature of the ones we dropped on them.
Even after all this time quality still counts.
My father was a naval bomb disposal officer in WWII. He’s told me stories about the crazy risks he and his buddies used to take simply because the Germans were so predictable in how they planted their boobytraps.
For example, if the retreating Germans put a boobytrap on a staircase they always placed it under the third riser. If my father was ordered to clear a building with a staircase he always walked up the first two steps then reached under the third to feel for the device.
Similarly he said the Germans could always be counted on to lay their landmines on a one meter grid. So after he found the first few mines he could mark off the whole field and walk freely down the rows … .