Controlled explosions

[Coldicote]

It is not unusual to read on the news that a bomb, grenade, mine etc from World War 2 has been found. Today's news carries information about a large WW2 bomb being found in Yorkshire and that it has been disposed of by a 'controlled explosion'. What actually is a controlled explosion? I've often wondered. Does any reader know?

[bookbinder]

"A controlled explosion" means that a group of experts (usually military bomb-disposal people) deliberately exploded the bomb. They examined the bomb, they identified its type, they figured out exactly what to do with it, they knew how much explosive to place on it, they knew just how far away they, and other people, had to be to be safe when the bomb exploded, and they knew exactly how many sandbags or how much earth to place around it. All this means that experts were in charge of exploding the bomb, and it didn't just explode on its own.

[saxy_jag]

I've been told that what they do is to put a measured amount of modern plastic explosive in beside the bomb and detonate that, and it takes the bomb with it.

Before that, as bookbinder says, they use all their gathered knowledge of WW2 bombs and explosives to work out exactly how much of everything to use.

Explosives deteriorate with age and can become very unstable, so I don't think it's possible to predict, 100%, what will happen, but it's far safer than if it were left or just detonated on its own detonator.

[webbo3]

i think they got it a little wrong, normally a controlled explosion is a lot smaller as they are only trying to destroy the firing and timing device, this explosion was far to big for that, it looks like some of the explosive went up as well.
bearing in mind these were 1 ton sandbags.

http://news.bbc.co.uk/1/hi/uk/8207831.stm

[Coldicote]

Many thanks for your replies. The BBC videos were particulary interesting, Webbo. Makes one think what it must have been like in WW2 with things like this blitzing the towns and cities.

[sag]

Pretty awful, Caldicote, and scary too!!!!

[anotheoldgit]

Yes it was very scary, these bombs where dropped on the civilian populations, and there were no inquiries regarding the amount of civilian deaths, such as there is now, in Iraq and Afghanistan.

If there are civilians in war zones then there in all probability there are going to be civilian casualties.