has a dud detonator ever really gone off?

Supposedly, the worst thing that can happen when working with explosives is for nothing to happen when you activate the detonator, because then you have to check it, and it might go off while you’re in an unsafe position (e.g. right next to it, examining the detonator).

Has this ever actually happened? Or is this just a product of the paranoia that keeps explosives experts alive?

Secondly, how could this happen, aside from a fuse being unexpectedly slow (like several dozen times slower than expected)?

For the comedians: no, I don’t need an answer fast, that’s the problem*.

*just kidding about that part. I’m curious about explosives, not suicidal.

I don’t know about bombs, but it happens with guns.

We used to function test M16 “bouncing Betty” anti-personel mines (US version of the German original). Each production lot would get originally tested (sampled) then retested at multi-year intervals. The mechanical fuze could be activated by pressure or pull-wire. The function test used only the pull-wire function.
Procedure:
Set up mine in ground; attach pull-wire; retire to bunker; pull the wire. After a short delay (to allow a soldier/cow/farmer to move off the mine; it would erupt from the ground (black powder expelling charge) while another short delay in the mine body burned; then detonate at head high to kill or maim much of the squad/herd.

The testing was due to aging/moisture/corrosion affecting the spring release mechanism, the initial delay column in the fuze, the expelling charge, and/or the delay column in the mine as it ascended.

When a “dud” occured (no function), standard practice was to wait 30 minutes then investigate/blow up the dud. After one dud, one crew (not mine) got involved in a heated pinochle game and was just headed out the door at the 45 minute mark when the mine functioned:eek:. The SOP was changed to “wait one hour”.

Your answer is yes.

Also, the US inventory has artillery/rocket/air delivered mines with delays built in. There is alway some variance in the delay times +/- the desired time. And of course there are outliers. TRIPLER on the board can provide more detail / hair-raising stories.

Interestingly the link to hang fire made reference to a Dud as being a devise that;

and then the Wiki link for Dud states;

I am not an explosive expert although i have worked around Blasting for 35 years and on occasion we would spot an UN-detonated booster (used in Mine blasting) like in this video,
That video was taken at the Mine i worked in and this was a weekly event and then some.
A shovel runner from another nearby Iron (taconite) mine was injured when a booster
detonated as she was loading Ore into a haul truck.
So again yes they can unless the compounds that are explosive were never added like a rifle cartridge without gun powder. This last example “could” then set stage for an even greater explosion.
Never say Never :wink:

Hi, I’m an EOD Technician, and yes, it happens.

What is colloquially called a ‘dud’ is just something I call a ‘failure to operate within parameters’. In other words, it has “failed to function” and this encompasses a variety of reasons. It could be that a spring in a nose fuze didn’t snap to, to line up the firing system. It could be that a nose vane on a -904 fuse for some reason didn’t revolve enough times to put the mechanics in line to fire. In any case, a ‘dud’ normally results in an UneXploded Ordnance (UXO) situation that I’ve responded to many, many times.

Me and my EOD sisters and brothers are specifically trained for just this thing: approaches to the item, evaluation of it, and recommended safing procedures. We usually know what ordnance we’re dealing with, and have the procedures to render it safe enough to move to a disposal point.

In our cases, has a detonator ever gone off? I can’t think of one past the 50’s where an EOD Tech has inadvertently detonated a ‘dud’. We know what we’re doing, and our job is to let it ‘go off’ under our controlled circumstances.

Tripler
EOD, and a Doper; Proud of Both.

Thanks for the info, all. I’m specifically curious about the detonators seen on mythbusters and other shows, where it’s triggered manually by an operator (usually by flipping a pair of switches simultaneously).

How would something like that fail and still be capable of triggering the detonator? Or is it the detonator itself that can go off unexpectedly after being triggered? What about slow matches (the string that burns at a known, constant rate)?

Well - we all know about the fireworks that seem to have gone out…

“Detonators” (and the term is a loose one), can’t just simply go off unexpectedly either untriggered, or triggered. The whole point of a detonating system or firing train is to control the actual detonation. Consider this; if I fired my shock tube initiator, and it failed to initiate my main charge, I’d consider that think unreliable, wouldn’t buy the product, and that company would be quickly out of business. On the other hand, if I did fire the initiator, and nothing happened, the last thing I’d want is the main charge to detonate while I’m heading downrange to fix my misfire.

I can’t talk to specific examples in Mythbusters without having really watched the show. I’ve seen a few episodes, but not that many. If people are flipping switches, then I would venture that electrical connections came loose, solder broke off, the battery was underpowered, etc.

The main charges are insensitive explosives–meaning, they are not so sensitive that an accidental bump or drop is going to detonate them. The Mk 82 GP bomb, with 192 lbs of ‘bang’ inside is insensitive, and there’ve been instances in crashes that the aircraft caught fire and burned, but the bombs did not detonate. Modern fuzing is specifically designed to fire after pre-set conditions or forces have acted on the fuze. For some of them to just randomly detonate is bad news for a lot of people concerned.

Tripler
You don’t wand ordnance randomly cooking off underneath the wing of an aircraft in flight. :smack:

Sounds like it’s just professional paranoia, then. And I can totally accept the idea that a “one in a million” chance is just too risky when you’re working with something that can kill (or even cause massive destruction) in an instant.

In my line of work in the oilfield (not explosive related) some people refer to this as chronic unease. if you never let yourself get complacent, and you keep that chronic unease, you’re always double-checking your double-checks, and you reduce the chances of missing something you oughtn’t have missed.

I don’t think your conclusion follows even a little bit from our experts’ comments. I also don’t think you have clearly explained what item(s) in the whole explosive train you consider to be the “detonator.” As such we probably have miscommunication contributing to misunderstanding.

I’m not sure of the “professional paranoia” you are referencing, and I did have to look back at your OP to get more context.

To answer your OP, yes the worst thing that can happen on a controlled shot is for a ‘misfire’. But that’s why I would wait a long length of time to make sure it wasn’t a ‘hangfire,’ or maybe a fault with a slow-burning M700 time fuze. I have methods to mitigate those dangers though, and I run through logical steps before I go, or send anyone downrange.

Satellite^Guy is absolutely correct. Every response is different. Just because two Mk 82s fell off the plane, one got jostled differently from the other. Just because Grandpa kept mortars from the war in his toolshed, one’s had some different thermal stress on the fuze, just based on position in the stack of them and exposure to sunlight*. When you let your guard down, your ass is toast.

But LSLGuy is correct. Granted, I don’t think you’re in the explosives field, so I give you a lot of leeway. However, if you say “detonator” to any random person on the street, here’s what they’d describe:
[ul]
[li]The silver box with an antenna and a toggle switch that the ‘bad guy’ holds.[/li][li]An electrical device that collects input from sensors, and sends a firing signal to the fuze’s firing system.[/li][li]Electrical devices on a weapon that initiate massive currents/voltage surges to exploding bridge wires or blasting caps.[/li][li]A mechanical device that strikes your primary, sensitive explosives to initiate detonation.[/li][li]Blasting Caps.[/li][li]A booster charge contained within a manufactured fuze.[/li][li]Any other combination of the above.[/li][/ul]

So, some of it is terminology of a manufacturer. Some of it is Hollywood gibberish. Can you be more specific on a particular fuze series?

Tripler
There’s a series of items in a firing train, and not all of them are ‘detonators.’

*Note: True story!

I like that term much better. It doesn’t have the implied judgement of “paranoia”, which I’ve apparently implied in my last comment, despite the disclaimer.

By detonator I am referring to the device one would place in a block of stable explosive (on Mythbusters, it’s almost always C4) to cause a proper explosion (vs. throwing bits of undetonated material all over).
**
More details:** [ol]
[li] These explosions are almost always done with the help of Sergeant J.D. Nelson, a bomb tech for the Alameda county sheriff’s department (his day job is “safing” suspected bombs). Sometimes they’ll have a retired FBI agent (Frank Doyle) helping out with the bigger explosions, or unusual explosives (e.g. when they tried to determine what farm chemical* was causing pants to spontaneously explode)[/li][li] As stated earlier, the explosive is usually a block of C4.[/li][li] Several shots include a spool of what looks like electrical wire, but could also be detcord (assuming that wasn’t dangerous, they’re very careful with explosives and even fireworks). [/li][li] Back in the bunker (or other safe location) the explosion is triggered by either:[ul][/li][li] flipping two switches on a control panel (first switch; say: “armed, (title of explosion) in 3, 2, 1”; second switch)[/li][li] simultaneously holding down two buttons on what looks like a radio transmitter [/ul][/li][/ol]

  • after some testing, they concluded the most likely culprit was sodium chlorate

Okay, then you’re talking about blasting caps.

“By the numbers,” as one of my instructors would say:

1.a. Sergeant Nelson, on a day-to-day basis is ‘rendering safe’ suspect packages for evidence collection and/or disposal. The Police have a slightly different set of criteria to operate with: they need evidence. Me? I’m military, I don’t care so much about prosecution. I just need to make the thing go away. The Police save everything they can for later court cases.

1.b. I :heart: C-4. And Comp-B too. :slight_smile:

1.c. ‘Bang’ is, like any other commodity, expensive. So, detcord, by the foot, has a cost, which is expended when the shot goes off. Electrical cord, however, is relatively cheap: it can be reused over and over again after every shot, assuming one still has continuity between the wires for the electrical power (you always test your wire before every shot). Again, not having seen the episode, he probably used several feet of detcord, tied a blasting cap to the end of it, connected his ‘firing wire’ to the blasting cap, then ran the firing wire back to his safe area. You may lose up to a foot or so on each shot, but just trim the insulation back and your wire is as good as new. It’s a matter of economics.

1.d, 1.e, and 1.f: Again, I’m normally in an expedient situation on a response, and while I have safeties, they’re not always churched up like that for a camera. I suspect there’s a bit of Hollywood goin’ on there for the T.V.

Well, if they were suspecting sodium chorate, they may have been using an brand different than what I’m used to using. I have two types of blasing caps at my disposal [sub]get it?[/sub]: electrical, and non electrical. The electrical comes with two wires that I connect to my firing wire to complete a circuit. The non-electrical is an open base, that I crimp on to detcord. I don’t know what commercial caps the Sergeant is using, so I can’t discuss the materials that are inside the cap.

That being said, electrical caps, by the physics of electricity and magnetism are susceptible to stray electromagnetic impulses. When you connect a 6’ lead of a cap’s wires to 500’ of firing wire, you now have a 605’ ground antenna. Lightning, or a random stray massive burst of RF radiation has the potential on paper to create enough voltage and thus current, over an ‘open’ (unshunted) line to initiate the blasting cap. This is a big “has the potential” though. Caps, since the 50’s, have been designed with bridge wires to avoid this, and have their leads shunted to prevent this. Even up to this day, they are handled with precautions we learn to minimize static (from our bodies–yes, the same kind that zap you when opening a door), are insulated out the wazoo to block any random RF interference, and are checked and re-checked for potential faults before I shove it up the butt end of my beloved plastic explosive.

It has happened in the past that a sensitive explosive in the cap didn’t detonate, but deflagrated in the cap, but still had enough power to detonate the main booster in the cap. So yes, statistically speaking, there are a few hangfires out there. However, everyone (who’s alive, that is) knows not to go running downrange the second your electrically initiated shot doesn’t go ‘bang’.

Specific examples? I have none. But I do know it has happened in the past, based on statistics, and what we learned in school. That’s why we have an art and science with rules on this sort of thing.

I am a trained professional. I am not on TV, but do not try this at home.

Tripler
Call me, I’ll bring you a popsicle while you wait.

Yeah, but probably a good idea for this show. Most episodes include at least one explosion, and they joke about and clearly have fun with the explosions, so they have to do something to remind the stupid people that this stuff is serious.

Okay, so the cautious approach (I assume they edit out waiting period) makes a lot more sense, now. Chances of a delayed explosion (after a suitable wait) are very slim, but still non-zero.

It’s like infection for surgeons, aircraft failures for pilots, drug side effects for pharmacists; you know it’s incredibly unlikely, but you still watch for and guard against it every time.

Sure. . . if that’s the way you want to frame it.
Tripler
Misfires suck.

It’s much quicker than " It may be unlikely*, but the experts also (seem to) spend a lot of time worrying about it, and go to (again, seemingly) great lengths to prevent it happening at the wrong place/time. The professionals know a lot more about this than I do. All things considered, their care is probably justified"

*based on your earlier comment that you’ve not heard about anybody accidentally detonating a presumed dud since the 50’s.