LAPD blast containment truck fails, seventeen people injured 6

[jrs87]

https://www.dailymail.co.uk/news/ar...illegal-fireworks-LA-goes-terribly-wrong.html

Someone did not read the manual.

 

[microwizard]

I guess the answer is if you have a hammer, you treat everything as a nail. If you have a box to safely blow stuff up, you put stuff in the box.

Operators are rarely like engineers with a curious mind, but people who want to get the job done, and in this case return the neighbourhood to the residents.

 

[Alistair_Heaton]

aye but you don't hit a picture frame pin with a sledge hammer

 

[RedSnake]

I would still like to know what is considered to be the volym of a soda can in the US

BR A

“Logic will get you from A to Z; imagination will get you everywhere.“
Albert Einstein

 

[JohnRBaker]

Your typical 'soda can' (where I grew-up we called them 'pop cans') in the US is 12 fluid ounces or 355 mL.

John R. Baker, P.E. (ret)
EX-'Product Evangelist'
Irvine, CA
Siemens PLM:
UG/NX Museum:

The secret of life is not finding someone to live with
It's finding someone you can't live without

 

[RedSnake]

Okey Tanks John.

“Logic will get you from A to Z; imagination will get you everywhere.“
Albert Einstein

 

[Alistair_Heaton]

In war zones they put some plastic in them and then fill them up with nuts and metal cutting in animal poo. Then use a drop hammer to fire a bullet percussion into the plastic which is triggered by a trip wire.

 

[IRstuff]

In the first article cited by the OP

However, 'improvised explosives' also were found that were too dangerous to move.

He described them as 40 home-made devices the size of Coca-Cola cans with simple fuses and 200 smaller but similar devices.

These IEDs were the ones being disposed of. The article claims 5000 pounds of fireworks, which obviously were not exploded in the containment vessel.

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert!

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[dik]

For that... they need a whole bunch of trucks.

Rather than think climate change and the corona virus as science, think of it as the wrath of God. Feel any better?

-Dik

 

[Alistair_Heaton]

I presume the guy they arrested is looking at a very long time in prison?

 

[Alistair_Heaton]

Must admit the burns and disposals of bulk the BDO's always did a test shot first with one or two then if that was fine doubled it until it got bum twitching.

But then again they never had anything as fancy as that contraption.

And they had us grunts to shift sand bags which they crafted into a pit which apparently was a special shape to focus the blast upwards.

 

[Artisi]

I showed this link and photos to a Thai police friend who was until very recently in command of the Northern region SWAT team, had to get my wife to translate a couple of the finer points into Thai and in turn translate a few questions back to me, his reaction was, a look of amazement, a shake of the head and x*"#*" in Thai.

It is a capital mistake to theorise before one has data. Insensibly one begins to twist facts to suit theories, instead of theories to suit facts. (Sherlock Holmes - A Scandal in Bohemia.)

 

[dik]

how about those that actually did the damage; is he responsible for that?

Rather than think climate change and the corona virus as science, think of it as the wrath of God. Feel any better?

-Dik

 

[MacGyverS2000]

how about those that actually did the damage; is he responsible for that?

It can (and has in the past) be argued in court that he is responsible... he created a dangerous situation by making the bombs, and the fact that someone else screwed up and made the situation worse doesn't necessarily absolve the original situation creator.

Dan - Owner

http://www.Hi-TecDesigns.com

 

[waross]

On the other hand may gross incompetence rise to the level of criminal negligence?
Not expecting that charge to ever be laid.

Bill
--------------------
Ohm's law
Not just a good idea;
It's the LAW!

 

[IRstuff]

No one died, so probably not. Plus, this might fall under the "qualified immunity," although that's a bit ironic.

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert!

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[spsalso]

If the police had been following proper protocol, I think it might make sense to hold the "owner" additionally responsible.

But they were not.

You might as well try adding charges for when a cop shoots himself while reholstering his weapon after arresting someone. Would a jury go for it?

Qualified immunity protects cops when they are attempting to do what a reasonable person would do, but turn out to be wrong. For this to apply, a reasonable person would have to have put 45 pounds of explosives in a container not designed for it, after being instructed not to. It would probably be argued that they THOUGHT they were not exceeding the weight limit.


spsalso

 

[MacGyverS2000]

I would be pretty surprised if someone doesn't have an order-of-magnitude rough feel for what 42 pounds feels like compared to 15...

Dan - Owner

http://www.Hi-TecDesigns.com

 

[RedSnake]

Not shore they actually got it that wrong, there is something not adding up here.

larger explosives — which were about the size of a soda can with a fuse — had about 1.5 ounces (42.5 grams) worth of flash powder.
Federal authorities who weighed the larger ones sade they were about 5 ounces (142 grams).

If the soda cans was the size JohnRBaker suggests 12 fluid ounces or 355 mL.
And the flash powder was 5 parts potassium nitrate, to 3 parts aluminum powder, to 2 parts sulfur
The cans would have contained approximately 49,7 gram potassium nitrate and sulfur approx. (2gram/cm3)
and 10,65 grams aluminum powder approx. (1 g/cm3).
Totally the cans would have contained around 60,35 grams of flash powder fully filled up.
That's more then 42,5 gr as was calculated by the people on site but it is definitely much less then the federal authorities calculation of 142 gr.

So either there wasn't flash powder in the cans, but something else, or the they use flash powder as a term for anything that can go bom!

/A



“Logic will get you from A to Z; imagination will get you everywhere.“
Albert Einstein

 

[waross]

I understand that there is a conversion factor involved and the value are equivalent weights rather than actual weights.

Bill
--------------------
Ohm's law
Not just a good idea;
It's the LAW!

 

[Auri]

there is something not adding up here.

cl = centiliter?

Then 1 cl = 10 cm^3

Your calculations were otherwise correct for the density of that mix. Keep in mind powder contains some air. It's typically 1-1.3 g / cm3 for blasting powders, 1.57 for C4.

I'm not sure how the bomb techs miscalculated by 3x after x-raying. It's possible x-ray was inconclusive and they overestimated the skill of the fireworks maker. Generally home-made/low-quality devices would be suspected to contain more functional material at the cost of safety & quality material. They knew the devices were leaking...

It also might reflect poorly on rigid police protocols if they could not take advantage of detonating a small sample to estimate yield.