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.

 

[jrs87]

https://patents.google.com/patent/US8621973B2/en?q=~patent/US20090044690A1

Quote from above patent (Read the entire patent please, this is for a competing device) >

A principal disadvantage of these prior art devices is that they are necessarily large and bulky because they rely for blast containment on a large internal chamber volume enclosed by a relatively thin spherical chamber body, often of aluminum. While providing greater physical volume can better contain and suppress a controlled detonation, it also requires a larger chamber opening. Such a large opening, while facilitating the loading of a threat device, necessarily results in a greatly increased door surface area. Thus the total separation force from a given internal explosion pressure are equally increased. When combined with relatively weak construction materials and unreliable door-sealing mechanisms, these prior art devices can become unreliable or even dangerous from a safety standpoint. Because of the stresses and deformation that necessarily accompany a detonation of any size (10 lb or TNT or more), certain of these aluminum-body spherical chambers are believed to be one-shot tools at best.

 

[spsalso]

Aluminum?

I'd go with styrofoam, with a heavy coating of enamel paint, inside and out, for added strength.

To secure the door, I'd use top quality twine, tied with a DOUBLE knot.


spsalso

 

[jrs87]

"Jiffy Pop" Containment Device

https://patents.google.com/patent/US7712405B2/en?q=~patent/US8621973B2

 

[jrs87]

One side of the clamping yoke can be seen in this still frame.

Half of clamp under tree

 

[jrs87]

Someone help me. Are these the soda can sized devices? They do not look home-made or improvised to me.

Source:

https://youtu.be/0HmmVgjOQfw

 

[jrs87]

The other side of the clamp was captured by the roof of the overturned car.

 

[Demented]

If those are homemade, then I am the queen of France.

https://youtu.be/0HmmVgjOQfw?t=143

So, how many boxes did they fit in there?

Precision guess work based on information provided by those of questionable knowledge

 

[TugboatEng]

I too am surprised to see a safety cap on an improvised explosive.

It does appear the door came off sideways and impacted the overturned car as the car is nearly cut in half through the b pillar. I'm sure the lid was deflected upwards and onwards by the car. I have seen the same thing happen with a bowling ball fires from an oxygen cylinder with 4 ounces of Pyrodex behind it.

 

[spsalso]

I think that's half the lock--two halve sliding open sideways--normally?

And I think the door flew WAY over to somebody's house.


spsalso

 

[jrs87]

spsalso,

I think you are correct. The hatch (without its hinge) flew blocks, struck a house and ended up in the yard. One half of the yoke clamp with the threaded rods still attached ended up under the tree as depicted. The other half hit the over turned car. The hatch/door did no strike the car.

 

[dik]

Over 50 years back they were doing experiments in explosive welding at the UofM. I was't involved with it at all, but they had a large sphere about 15' or 20' dia and they were using CIL sheet explosive for the welding. The sphere was sealed, and I'm pretty sure a partial vacuum was created to minimise the effects of the blast. They were just using small 'chunks' of the sheet explosive, about 3"x6"; it was about 3/16" thick if memory serves.

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

-Dik

 

[IRstuff]

They do not look home-made or improvised to me.

I expect that they labeled them as "improvised" because they had no markings and no manufacturing information. Doesn't mean they weren't "manufactured;" there were lots of garage shops in Iraq and Afghanistan that could crank out explosively formed projectiles (EFPs) that were both professional looking and effective.

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

https://www.youtube.com/watch?v=BKorP55Aqvg

faq731-376 forum1529 Entire Forum list

http://www.eng-tips.com/forumlist.cfm

 

[spsalso]

there were lots of garage shops in Iraq and Afghanistan that could crank out explosively formed projectiles (EFPs) that were both professional looking and effective.

It's not right to discount the many other professionals throughout the world,beyond Iraq and Afghanistan, that can do this kind of work. I think it's important to acknowledge that the world is full of people who are competent to assemble explosive devices.

Except, perhaps, the LAPD. Not that they WOULD, of course.....


spsalso

 

[waross]

world is full of people who are competent to assemble explosive devices.

Except, perhaps, the LAPD. Not that they WOULD, of course.....

They don't seem to be competent to even disassemble explosive devices. grin

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

 

[IRstuff]

They don't seem to be competent to even disassemble explosive devices. grin

I'd say they did a bang-up job ;-)

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

https://www.youtube.com/watch?v=BKorP55Aqvg

faq731-376 forum1529 Entire Forum list

http://www.eng-tips.com/forumlist.cfm

 

[TugboatEng]

Cover your ass. Always label as IED so that when something goes wrong you can blame the unpredictable nature of IED. The evidence destroys itself in either case so nobody will know.

 

[spsalso]

Are there ISO standards for IED's?

Might be time to write a proposal and kick it upstairs (did I get that right?). GOTTA bring the EU in on this!

We CANNOT have any fly-by-night group building these without conforming to international standards.


spsalso

 

[Alistair_Heaton]

Aye get the European commission on it.

No IDE parts can be used from main land UK for future IRA or unionist terrorism if they are smuggled in with chilled meat products.

 

[Alistair_Heaton]

There was a story of some sappers blowing some rocks and tree stump out down in a valley in Germany.

Bang ground goes up and suddenly they is loads of water appearing.

A muffled crump is heard at the top of the hill as a water tower tank implodes after 20 mins.

Hey boss I though you said we were blowing stuff up today not killing things by giving it a blow job.

The qmsi didn't even look at him... Start running son back to camp and don't stop until I find you. If you get there before us start coming back.

 

[RedSnake]

For the lid flying of look at post 4 Jul 21 07:40


Well at least the Canadians seems to have this under control.
If you want to find European specialist's go to Malta, there is a fire display home manufacturer i in almost every garage.

https://www.nrcan.gc.ca/sites/

http://www.nrcan.gc.ca/files/mineralsmetals/files/pdf/expl-expl/2015-G05-05E-IG.pdf

F.2 - Display Fireworks
The default NEQ of display fireworks that have been classified 1.3G for transportation is 75% of gross mass.
For display fireworks containing flash powder* that have been classified 1.1G for transportation (i.e. salute aerial shells), the NEEQ (TNT equivalency) must be used.
The NEEQ in this situation is 70% of NEQ.
The NEQ would be 75% of gross mass.
Otherwise, the NEEQ (TNT equivalency) for all other display fireworks classified
1.1G for transportation (i.e. shells with diameter size > 155mm) is 50% of NEQ.
Again, the NEQ would be 75% of gross mass.

It's typically 1-1.3 g / cm3 for blasting powders

So (355 ml x 1,3 gram/cm3 x 0,75)/2 = 173 gram TNT ekvivalens.

Federal authorities who weighed the remains after the blast calculated that the weight was actually more than 42 pounds (19 kilograms) in the standard measurement. The smaller explosives were actually 1.37 ounces (38.9 grams) and the larger ones were about 5 ounces (142 grams).

/A




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