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Continuation LAPD blast containment truck fails, the IG report is published

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I thought this was 'old news'. I could swear that we had already heard this story.

John R. Baker, P.E. (ret)
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
 
Events are quick, the investigations drag out, and sometimes find useful and new or not previously disclosed information.
This report dated March 1 2022 addresses some of the organizational failures leading to the event.

This is one tidbit
The IG report said:
The number of training hours for 2021 was 3,042 with six months of the year completed, which indicates the potential of a continued downward trend in the number of training hours completed by Bomb Squad personnel this year. The OIG believes that this reduction in overall training hours from year to year since 2016 is an issue that should be addressed by the Department.

There is some information about the explosive capacity, both from testing, and from the OEM manual.

The IG determined that there are a number of causes (there is never just one) Conclusion section page 41.

Screenshot_from_2022-02-26_13-58-05_luzktg.png
 
That's funny. So it hasn't happened yet? Call me in a few days.
 
The federal report came out last September, so probably old news; the referenced ET thread ended in August, so apparently people lost interest in the story here. The report seems to be hard to find

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! faq731-376 forum1529 Entire Forum list
 
My quick read-through has me thinking that the calculations for the disposal are based on weight of explosive material, but there was no scale available to use.

They actually opened up one each of the "IED"s, and had a sample they COULD have weighed.

So they apparently NEEDED a scale, but no one ever thought to actually get one, and install it in the special bomb-disposal vee-hickle.

For some reason, my inner 5 year old keeps hearing the word "stupid", over and over. But relatively highly paid, let's not forget.


spsalso



 
Holy moses.

Actually amazed it never blew up before.

The limit was 15 pounds of C4/ 19 lbs of TNT.

The bomb techs thought it was 40.

The charge they used was 9 lbs.

No one ever did any calculations or notes.

So the reported previous explosions could have
been a lot more.

Plus there doesn't seem to have been any maintenence procedures for the TCV.

I never liked the design of the closure mechanism as it isn't a fail safe design and could easily start to crack unseen.

Unbelievable really.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.
 
That was the craziest part. They thought they were overloading the unit and they did.

The supervisor's comments... I let them come up with the plan.

How did they get so many people of such high incompetence together in one group?
 
Ignorance and incompetence and a good deal of complacency. The containment had likely worked so effectively in the past it gave them too much confidence.

But as most of us would know and any bomb technicians SHOULD know that containing an explosive can be readily counter productive if the containment is not strong enough.

At least Finnish amateur with home made explosive containment vessels are more sensible.
 
The technicians HAD A SCALE, but didn't bother using it for the IEDs, only for the counter-charge, and only estimated the weight of the IEDs by feel, and guess and by golly. Seriously bad protocol, and the only reason they weighed anything at all, is their log sheets require them to enter the weight of the countercharges to prevent theft, presumably, but not the actual NEW of disposed ordnance.

Page 31 said:
Before the materials were placed into the TCV, Logistics Officer A used a scale to weigh th counter charge. This was a common practice utilized by the logistics officers because the information could be recorded on a post-blast log that tracks the amount of material taken from the Bomb Squad's explosives magazines.


TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! faq731-376 forum1529 Entire Forum list
 
Yes, it's like they expected the countercharge to somehow 'destroy' the IED without actually triggering its explosive material.

John R. Baker, P.E. (ret)
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
 
No, they understood that the countercharge's purpose is to ignite the explosive material in the IEDs, but the lead technician simply held the IED by hand and guessed at the weight by uncalibrated feel, which worked in the past, until it didn't this time. They simply got lucky that previous hand "measurements" didn't exceed the NEW limit of the vessel in prior disposals.

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! faq731-376 forum1529 Entire Forum list
 
Re: the scales, or lack thereof

I do confess to skipping a bunch of stuff in the middle. I was lured away by that "work" thing that Maynard Krebs has trouble with.

Here's what I read that lead me to believe they didn't have a scale available (next to the last page):

"2. The Department should require appropriate measuring scales to be included as mandatory equipment in each Bomb Technician utility truck as well as on the BAT."

Reading that, I assumed that line was generated due to a lack of scales wnen/where they were needed.


spsalso
 
Also makes you wonder if they overloaded it many times before which weakened the TCV.

They don't really seem to have picked up on this in the report.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.
 
The quote above is from the OIG report, so that says that the bomb techs had a scale, and always did, since every use is documented with the weight of the countercharge used. Presumably, they audit the weight used against the remaining weight of countercharge material.

Also makes you wonder if they overloaded it many times before which weakened the TCV.

They don't really seem to have picked up on this in the report.

That was covered in the failure analysis report commissioned by the LAPD, which concluded that there was only one over-spec explosion experienced by the vessel; whether that would be same conclusion that any another lab might might is unknown.

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! faq731-376 forum1529 Entire Forum list
 
I do now see that there was a scale available.

I wonder, then, why the entry I quoted was made.

Perhaps by having multiple scales in place, it would emphasize that they are there to be used, rather than not.



spsalso
 
Having a scale, and actually using it only changes the problem.

The containment vessel was rated for some weight of a KNOWN explosive. 15 pounds of C-4 or 19 pounds of TNT.

The containment vessel is used to detonate and contain UNKNOWN explosives.

How is the bomb squad supposed to figure out the weight of the UNKNOWN explosive that does not exceed the explosion power of the rated KNOWN explosive?

There are commercial explosives that are more powerful than C-4.

Sensitivity and stability are design criteria for commercial explosives. The designer of an IED may have different design priorities.

The decision chart for this doesn't seem like it offers any great outcomes:

1. Could it go boom? Yes, no, I don't know.
2. Could it make a bigger boom than C-4? Yes, no, I don't know.
3. Could it go boom if you try to move it? Yes, no, I don't know.
4. Wouldn't you rather go have a beer on the beach? Yes.
 
Having a scale would not improve on the ignorance and imcompetence shown.

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

-Dik
 
It's unclear what the techs had at their disposal ;-) with respect to identifying the explosive type. Certainly, a number of explosives can be identified by color or texture. There are gadgets that can determine the composition of some explosives.

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! faq731-376 forum1529 Entire Forum list
 
MintJulep,

If the techs don't know what they have, they might as well assume it's the worst case. I expect there IS an upper limit.

Decision chart:

1. Could it go boom? Sure. That's why we're here.

2. Could it make a bigger boom than C-4? Perhaps. What's the BIGGEST possible boom? If we go that route, we get to go home.

3. Could it go boom if you try to move it? Not likely, since this guy stored this crap behind his house, and obviously moved it around to do that. BUT. We will make every effort to be "user-friendly". IF, in our highly educated professional opinion it MIGHT go boom if we move it, we have those robot dog things and those AI tracked vehicle things and........

4. Wouldn't you rather go have a beer on the beach? Yes, but the pay is lower.


spsalso

 
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