why don’t people who disarm bombs (with wires) not cut all of them at once

1.00K views

Is it because, one of the wires when cut, makes the bomb explode?

In: Other

7 Answers

Anonymous 0 Comments

Bomb difusal in movies is very different from real life bomb difusal. Most bombs will be disarmed just by cutting a random wire and does not contain any traps for bomb disposal crews. However a big problem is that you might accidentally short circuit some wires so the bomb goes off unintentionally. The best way to prevent this is to cut one wire at a time and make sure it is safe before you cut the next wire. Cutting them all at once carries a huge risk of short circuiting them. There was one notable bombing in August 1980 which did look like a classic plot for a movie and did include traps for the bomb disposal team. Instead of trying to defuse the bomb using wire cutters and risking someone blowing themselves up in the process the FBI decided to cut all the wires at once using an explosive charge. Nobody knows exactly what went wrong, if they used too little or too much or if they placed their charges wrong. In any case it did not work as well as they had hoped an the bomb detonated.

Anonymous 0 Comments

Other reasons aside, cutting all at once is almost impossible when compared to the speed of electric current. So unless you’re lucky enough to cut them in correct sequence, you’re boomed.

Anonymous 0 Comments

Once it is set, the bomb is being prevented from exploding before the timer reaches 0 by a signal. As long as the detonator keeps receiving this signal, it will not detonate the bomb. If you cut the wire carrying that signal, the detonator will no longer receive the signal so it will think that the timer has reached zero and promptly detonate the bomb.

Anonymous 0 Comments

[removed]

Anonymous 0 Comments

Actual former bomb tech here (USAF EOD).

Some of the other things people are saying are right to varying degrees.

Another very important point I didn’t really see mentioned is that a bomb tech’s life is a valuable thing. The military spent hundreds of thousands of dollars and a solid year training me before I was considered anything more than an apprentice. So they wouldn’t risk my life over something trivial. If a job could be done remotely, by a robot, or by placing a tool and activating it after I was safely away, that would always be priority 1. My team leader in Iraq did a “hand entry” on a device that he really did not need to. He disarmed it successfully, and was thoroughly chewed out by leadership afterward. He was very nearly dismissed and sent home.

As a final fun fact, in one of our advanced IEDs classes, we learned a relatively simple way to make a firing circuit that could detonate a bomb through the wire that you just cut.

Anonymous 0 Comments

Long story short, because disarmament is dangerous and bomb disposal is not only easier, but safer. Its actually pretty rare to see true “disarmament.” Usually a bomb tech will elect to blow-in-place, or BIP the device after securing is under a blast shield, or use what’s called a disruptor charge which is essentially a shotgun shell filled with water to destroy the bomb’s trigger mechanism without causing detonation.

Anonymous 0 Comments

Most machines are made ‘fail safe’, meaning they will shut down if some part of the system fails. Think of a lawnmower – you have to hold down the handle for it to work. That’s so if the owner say collapses while using it, it doesn’t continue to spin it’s lethal blade. A bomb designer, depending on the level of evil, could have designed their bomb around the opposite principle. The circuit or mechanism is actually *preventing* the bomb from going off, so it will explode of the interrupted.

If this is the case, bomb disposal needs to be carefully planned and carried out. More likely, they will detonate it under controlled conditions.