Sciencemadness Discussion Board
Not logged in [Login ]
Go To Bottom

Printable Version  
 Pages:  1  
Author: Subject: Two car bombs found in West End-detonation of propane possible?
tito-o-mac
Hazard to Others
***




Posts: 117
Registered: 30-6-2007
Member Is Offline

Mood: No Mood

[*] posted on 30-6-2007 at 01:29
Two car bombs found in West End-detonation of propane possible?


Police have confirmed they are now investigating the discovery of two car bombs in the West End of London.

Another Mercedes, with a bomb made up of 60 litres of petrol, gas cylinders and nails, had been found outside a nightclub in Haymarket at 0130 BST.

"There was a considerable amount of fuel and gas canisters, as in the first vehicle. There was also a substantial quantity of nails," he said.

Police also found a bag covered with a blanket, possibly containing high explosives.

A leading explosives expert also mentioned that such an explosion of a propane gas tank would create a fireball the size of a house.

I was pondering if ever, what could have made the propane gas detonate and create such a fireball?

I have read up on atomized particle explosions, but I am not convinced that is it the factor that could have caused such devastation?

I have looked up the internet and found this article, probably a cause : If a highly flammable substance is atomized, or, divided into very small particles, and large amounts of it is burned in a confined area, an explosion similar to that occurring in the cylinder of an automobile is produced. The tiny droplets of gasoline burn in the air, and the hot gasses expand rapidly, pushing the cylinder up. Similarly, if a gallon of gasoline was atomized and ignited in a building, it is very possible that the expanding gassed would push the walls of the building down. This phenomenon is called an atomized particle explosion. If a person can effectively atomize a large amount of a highly flammable substance and ignite it, he could bring down a large building, bridge, or other structure. Atomizing a large amount of gasoline, for example, can be extremely difficult, unless one has the aid of a high explosive. If a gallon jug of gasoline was placed directly over a high explosive charge, and the charge was detonated, the gasoline would instantly be atomized and ignited. If this occurred in a building, for example, an atomized particle explosion would surely occur. Only a small amount of high explosive would be necessary to accomplish this feat, about 1/2 a pound of T.N.T. or 1/4 a pound of R.D.X. Also, instead of gasoline, powdered aluminum could be used. It is necessary that a high explosive be used to atomize a flammable material, since a low-order explosion does not occur quickly enough to atomize or ignite the flammable material.

[Edited on 30-6-2007 by tito-o-mac]
View user's profile View All Posts By User
JohnWW
International Hazard
*****




Posts: 2849
Registered: 27-7-2004
Location: New Zealand
Member Is Offline

Mood: No Mood

[*] posted on 30-6-2007 at 02:39


There would have to be access to and sufficient mixing with oxygen, for incendiary materials like gasoline, natural gas, LPG, etc. to be explosively detonated by self-propagating combustion, as well as heating to above the flash point of the fuel-air mixture. The "conventional" explosive (e.g. TNT, nitroglycerin, RDX, nitrocellulose, TATP, NH4NO3, NH4ClO4, initially detonated with a heavy metal azide or fulminate set off by a current from a timing device) packed inside the gas bottles and gasoline containers and nails etc. would probably have provided the necessary heating and (on rupturing the gas bottle and gasoline containers) mixing with air.

The only thing worse would be if some of Lugovoi's left-over KGB-supplied polonium-210 had also been added to the mixture.
View user's profile View All Posts By User
Organikum
resurrected
*****




Posts: 2228
Registered: 12-10-2002
Location: Europe
Member Is Offline

Mood: fluffy!

[*] posted on 30-6-2007 at 04:04


Every car has about 60l of petrol. Wtf?

Looks like they got the car of a roofer. Nails for roofing, LPG for soldering and petrol to drive the fucking car. Roofers beware! You are terrorists.

To set off a bomb made of petrol and LPG it needs some sophisticated methods and I have not yet encountered any working descriptions on the net how to do this.
If this would be so easy the US army would be in for a hard time in Iraq and the rest of the world, taking in account the power which is theoretically in just one liter of petrol. But it isn´t as we know.

Either a roofer, idiots, or a scare to destroy our last liberties. I bet the on the last,




[Edited on 30-6-2007 by Organikum]




Restrict alcohol and Tobacco.
Legalize everything else.
Mandatory LSD for politicians and Franklyn.
View user's profile View All Posts By User
unionised
International Hazard
*****




Posts: 4123
Registered: 1-11-2003
Location: UK
Member Is Offline

Mood: No Mood

[*] posted on 30-6-2007 at 09:42


If there had only been one bomb then I might agree with you about the roofer.

"To set off a bomb made of petrol and LPG it needs some sophisticated methods "
A petrol bomb isn't that sophisticated.
The idea that petrol and propane are difficult to expolode seems at odds with the facts that petrol is used in engines specifically because it does explode and that gas explosions are fairly common.
View user's profile View All Posts By User
markgollum
Harmless
*




Posts: 46
Registered: 21-2-2004
Member Is Offline

Mood: No Mood

[*] posted on 30-6-2007 at 10:52


Bah, from the descriptions I have read it seems most probable that these "car bombs"
were useless garbage as far as doing any sort of damage.
Since when can you use a gaseous air/fuel mixture to convert bulk nails into deadly projectiles? you really can't especially if you are simply igniting the mix.
To really get some punch out of an air/fuel mix you need to use a good HE booster on the proper mix which for propane and petrol only works within a VERY narrow range.
The geometry of a car is completely unsuitable for this type of device and since the energy density is very low and the volume of detonating material is very high these devices are not intentionally used for accelerating pieces of metal.

[Edited on by markgollum]
View user's profile View All Posts By User
tumadre
Hazard to Others
***




Posts: 169
Registered: 10-5-2005
Member Is Offline

Mood: No Mood

[*] posted on 30-6-2007 at 10:55


well the only way to know is to do it yourself:D:D:D:D
View user's profile View All Posts By User
JohnWW
International Hazard
*****




Posts: 2849
Registered: 27-7-2004
Location: New Zealand
Member Is Offline

Mood: No Mood

[*] posted on 30-6-2007 at 11:30


But was it really Al Qaeda or the Taliban at work, in London? Who paid for those two spanking new Mercedes cars which, being undamaged, the pigs will presumably appropriate for their high-ranking officers to drive, and which (together with their cargos) must have cost hundreds of thousands of $s, assuming they were not stolen? I would have thought that Al Qaeda would have been too smart for something like that not to succeed, and too suicidal not to use suicide bombers instead, like what they do in Baghdad. It looks like another 911-style "own goal" to garner political support for the Government.

P.S. We may never really know for sure whether Al Qaeda was behind the 3 failed car bombs (all of which were rigged in the same way, copying those used in Iraq, but all had the same defect in the detonating mechanism) in London and Glasgow, for the simple reason that they would not want to be made to look silly by claiming responsibility for the 3 failed attacks. However, we do know now that the immediate perpetrators were Muslim criminals, in view of one of those caught in Glasgow screaming "Allah, Allah, Allah" as he was being arrested by a pig. So they did it in the name of and on orders from Dog-Spelled-Backwards, and on promises of a free and premature trip to Paradise with 72 virgins as their reward for killing themselves and as many other people as possible. But it has come out that the British Government received two weeks' warning of the attacks, including that London and Glasgow were to be targets, but failed to act upon it, so it does look like another 9/11-style "own goal".

[Edited on 2-7-07 by JohnWW]
View user's profile View All Posts By User
franklyn
International Hazard
*****




Posts: 2998
Registered: 30-5-2006
Location: Da Big Apple
Member Is Offline

Mood: No Mood

[*] posted on 30-6-2007 at 14:38


This latest car bomb in London marks a troubling trend. Since acquisition of
precursors for improvised explosives is closely monitored , the ever resourceful
urban terrorist adapts by fabricating fuel air demolitions. Producing a fireball
alone is hardly worth anyone's effort unless this occurs in an enclosed area
since most of the heat rises with the flame scarcely impacting the surroundings.
In the past ( going back years ago to germany ) acetylene had been used on
a small scale to enhance air blast in an enclosed place such as a dance club.

Improvising an effective FAE ( fuel air explosion ) is technically hard to achieve
correctly for the desired result , requiring exquisite timing between the dispersion
of combustible fuel vapor and it's ignition; a matter of milliseconds over a narrow
window of time. The percentage of fuel vapor in air must be in the explosive
range in order to produce blast overpressure. When aerosolized , a liquid fuel
will drop the temperature within the cloud to freezing as it absorbs heat from
the air , hindering it's ignition , as it occurs when you try to cold start a car.
Dispersal of a liquified gas fuel such as propane or butane will be subfreezing
although these do have a lower flash point. For this reason ethylene oxide has
been tried for use in munitions.

I recall that a member of this forum posted video of their tribulations when trying
to achieve ignition of explosively aerosolized fuel. Not as easy as it seems.
Pre-heating the fuel to increase it's vapor pressure and ignition is the answer.
BLEVE ( Boiling Liquid Expanding Vapor Explosion ) is the result when a tank car
on fire ruptures from the internal pressure spewing the contents into the air.
Similarly certain munitions achieve preheating and igniton with thermite.

The vehicle in London aroused suspicion when it was observed to be emitting
vapors. Likely the preheating phase had begun. Gasoline , Propane , Butane ,
untold blended flamables and thermte are not materials that can be monitored
and the technical hurdles which do require sophisticated engineering are
surmountable. We can rely on experiencing more of this type of attack.

.
View user's profile View All Posts By User
Nerro
International Hazard
*****




Posts: 596
Registered: 29-9-2004
Location: Netherlands
Member Is Offline

Mood: Whatever...

[*] posted on 30-6-2007 at 14:46


Gentlemen please don your tinfoil hats!

It is awfully coïncidental for all this to happen in conjunction with Gordon Brown's assumption of power isn't it?




#261501 +(11351)- [X]

the \"bishop\" came to our church today
he was a fucken impostor
never once moved diagonally

courtesy of bash
View user's profile View All Posts By User
Organikum
resurrected
*****




Posts: 2228
Registered: 12-10-2002
Location: Europe
Member Is Offline

Mood: fluffy!

[*] posted on 30-6-2007 at 20:53


Propane and gasoline are cheap and abundant. If this stuff would make feasible explosive devices for "the urban terrorist" or anybody else we would see it every day everywhere. The fact that this just doesnt happen shows that gasoline and propane are NO feasible explosives. Point proven.
Doesn´t say that I could not make a nice bomb from the stuff as other members here could. But we are amateur scientists and no terrorists whatever Polysam may believe. At least not now.

When the cops raided my home they found some pipes and a lot of hexamine and they immediately asked me if I intended to build bombs. Wtf? Why should I want to blow somebody up? Is the whole world paranoid?

I am more and more convinced that the press and media at all, and the fucking politicians are doing way to much cocain, they are getting more and more paranoid every day. Somebody really has to spice the water supply of the parlaments and the press with LSD to set things straight again.
We need less psychopharmaca and more psychodelics.
Thats what I think.

Every car a rolling bomb?
Isn´t this going overboard here?
I mean WE know that you cannot explode AN and diesel just so without some special tricks & ingredients and now we set the world on fire with some LPG and gasoline?

I don´t get this anymore.

Sorry for the rant.

[Edited on 1-7-2007 by Organikum]




Restrict alcohol and Tobacco.
Legalize everything else.
Mandatory LSD for politicians and Franklyn.
View user's profile View All Posts By User
tito-o-mac
Hazard to Others
***




Posts: 117
Registered: 30-6-2007
Member Is Offline

Mood: No Mood

mad.gif posted on 1-7-2007 at 00:06


I totally agree with you organikum. THIS ENTIRE WORLD HAS GONE PARANOID. Friggin police arresting boys playing with sparklers, and now they are beginning to ban fireworks.. what's next? oh, being arrested for having a barbecue using a LPG gas cannister?
I guess the main idea was the detonate the high explosives and atomize the particles of the lpg(virtually imposible) to create a fire ball. I guess the petrol was just for havok. This is extremely similar to the recent Tokyo spa gas explosion. A better sauna than expected!
[Edited on 1-7-2007 by tito-o-mac]

[Edited on 1-7-2007 by tito-o-mac]
View user's profile View All Posts By User
unionised
International Hazard
*****




Posts: 4123
Registered: 1-11-2003
Location: UK
Member Is Offline

Mood: No Mood

[*] posted on 1-7-2007 at 10:52


"Propane and gasoline are cheap and abundant. If this stuff would make feasible explosive devices for "the urban terrorist" or anybody else we would see it every day everywhere. The fact that this just doesnt happen shows that gasoline and propane are NO feasible explosives. Point proven."
That only proves the point to people who have never heard of a petrol bomb (AKA a Molotov cocktail. )
http://en.wikipedia.org/wiki/Molotov_cocktail
I'm not saying that these are fully engineered fuel/ air bombs; just that they are very cost effective and practically impossible to ban.
If I got a good fire going round a propane cylinder then eventually the cylinder (or it's burst disk) would fail. At that point the propane would spew out rapidly and catch fire as it did so. A big cylinder could easily produce an impressive fire ball. Not technically a detonation but not something you want to be near. Something like this without the giggling people.
http://www.youtube.com/watch?v=0os7ECWrwtM
View user's profile View All Posts By User
Organikum
resurrected
*****




Posts: 2228
Registered: 12-10-2002
Location: Europe
Member Is Offline

Mood: fluffy!

[*] posted on 1-7-2007 at 11:41


A Molotov cocktail is no explosive device but a firestarter, a gascylinder doesn´t explode, the Hindenburg didn´t explode but burn down nicely (and most passengers survived).

What are you doing here on this board all the time actually?




Restrict alcohol and Tobacco.
Legalize everything else.
Mandatory LSD for politicians and Franklyn.
View user's profile View All Posts By User
evil_lurker
International Hazard
*****




Posts: 767
Registered: 12-3-2005
Location: United States of Elbonia
Member Is Offline

Mood: On the wagon again.

[*] posted on 1-7-2007 at 16:19


Ummmm what would happen if you got a propane cylinder, distilled the propane into a high pressure cylinder, hooked that cylinder to a high pressure oxygen cylinder, and opened up a valve between the two and put rigged up an electric ignitor to the whole bit?



Not all chemicals are bad. Without chemicals such as hydrogen and oxygen, for example, there would be no way to make water, a vital ingredient in beer.
View user's profile View All Posts By User
12AX7
Post Harlot
*****




Posts: 4803
Registered: 8-3-2005
Location: oscillating
Member Is Offline

Mood: informative

[*] posted on 1-7-2007 at 17:07


If you get the ratio right, then what happens depends on the peak pressure. If the mixture can detonate rather than deflagrate, it's probably not going to end well. Those high pressure cylinders are rated for thousands of PSI, so a mere deflegration, especially starting from one end (i.e., more burn time as opposed to burning from the center), may not cause enough pressure to explode one.

Tim




Seven Transistor Labs LLC http://seventransistorlabs.com/
Electronic Design, from Concept to Layout.
Need engineering assistance? Drop me a message!
View user's profile Visit user's homepage View All Posts By User This user has MSN Messenger
nitro-genes
International Hazard
*****




Posts: 982
Registered: 5-4-2005
Member Is Offline

Mood: No Mood

[*] posted on 1-7-2007 at 17:17


Making a true fuel-air-explosive (detonating fuel cloud) out of gasoline or a propane tank is next to impossible and would require more exotic fuels and/or additives to work reliably. To do so as an amateur you would need months of extensive experimentation and a lot of know-how to come up with something that actually works reliably.

BLEVE's by rupturing gas tanks can look pretty intimidating, though the overpressures produced are too low to be of any real threat, especially in the open. Adding nails sounds for this reason more like a bad episode of MacGyver than a terrorist attack. Maybe if someone would have felt the need to crawl inside the trunk and hug the propane tank at the time it "detonated" it would have made a casualty.

Still wondering if the propane mentioned by the media could have actually been propane-N2O, oxy-acetylene or oxy-MAPP gas, without a doubt it is all the same to them...

[Edited on by nitro-genes]
View user's profile View All Posts By User
tito-o-mac
Hazard to Others
***




Posts: 117
Registered: 30-6-2007
Member Is Offline

Mood: No Mood

[*] posted on 1-7-2007 at 20:04


It is called "gas patio", used for cooking
View user's profile View All Posts By User
franklyn
International Hazard
*****




Posts: 2998
Registered: 30-5-2006
Location: Da Big Apple
Member Is Offline

Mood: No Mood

[*] posted on 1-7-2007 at 20:59
A lot closer than you think


http://www.pittsburghlive.com/x/pittsburghtrib/news/specialr...
Look at the right sidebar also

http://www.pittsburghlive.com/x/pittsburghtrib/train/

.
View user's profile View All Posts By User
tito-o-mac
Hazard to Others
***




Posts: 117
Registered: 30-6-2007
Member Is Offline

Mood: No Mood

[*] posted on 1-7-2007 at 23:43


I looked up the video and the results were devastating. Buildings within 200m of the blast radius were incinerated! " LPG is so flammable, a detonation of one railcar can cause second-degree burns more than a mile away. " "Detonating one LPG railcar can cause second-degree burns more than a mile away. A terrorist who explodes 18 LPG tank cars would unleash as much energy as the atomic bomb that was dropped on Hiroshima in 1945, according to federal reports. "

Worse than I thought so!

Anyway,The Straits Times, Monday 2 July,2007 reported:"On a slightly encouraging note, it is clear that those who perpetrated the two attacks were not very sophisticated. They do not appear to have high explosives. Instead, the attacks relied on a combination of large quantities of petrol and gas canisters, which could have been triggered of by a small explosive device. The aim was to create a masive fireball which would incinerate everything in sight, very similar to the spectacular "special effects" used in mnay Hollywood movies. But. although the technology is simple and the materials are both readily available and difficult to control(since they are in common daily use), exploding such incendiary devices is not as easy as it sounds. The highly violatile materials also need to be in the right amounts and the mixture of fuel and oxygen must be correct for a big fireball to develop." Maybe a deodorant can is one such simple example. It is aerosol, and is highly flammable. From there, one can think of more ideas to conduct an experiment.:o

BTW,Organikum,"What are you doing here on this board all the time actually?", is that I never logout, and I live in asia, so the timeline is diferent...

[Edited on 2-7-2007 by tito-o-mac]
View user's profile View All Posts By User
tito-o-mac
Hazard to Others
***




Posts: 117
Registered: 30-6-2007
Member Is Offline

Mood: No Mood

[*] posted on 2-7-2007 at 00:19


I get the point Unionised. The video propane vs. shotgun is probably the sort of thing those terrorists wanted, exept they had many propane tanks and loads of petrol. The idea is too set the propane tank on fire first(but not detonate it!), without allowing any explosion to occur. The ignition has to be done with the petrol. I think the terrorists thought the petrol was enough to set off the initial ignition and than the detonation, while triggered with the cellphone detonator. The reason why the police found the two phonecalls, were one, to set off a fire with a small amount of petrol, and the second phonecall, was probably to ignite the second load of petrol (most likely significantly larger than a first), to break the casing of the cylinder, allowing the pressurised propane gases to quickly escape. But the second petrol had not enough time to rupture the casing of the cylinder. If only a little ammonium nitrate was attached to each cylinder and detonated, only than would they produce a hell of a fireball. Even an axe could have done it. Point proven(though I'm not to sure). If anyone believes it is incorrect, than I suggest you go on ahead and prove it! I would like to here from your opinions. Nevertheless, M15 has the final verdict!

The car that crashed into the airport was rather a sily idea. They even forgot to survey to site firs. Even driving around aimlessly knocking down people could have resulted in more casualties than that burning molitov cocktail!

[Edited on 2-7-2007 by tito-o-mac]

[Edited on 2-7-2007 by tito-o-mac]
View user's profile View All Posts By User
Organikum
resurrected
*****




Posts: 2228
Registered: 12-10-2002
Location: Europe
Member Is Offline

Mood: fluffy!

[*] posted on 2-7-2007 at 01:01


The point is as we know here that this just doesnt work.

And yes, there is a bunch of wannabee terrorists out there. Muslims, highschool kids, idiots, sociopaths of any kind. Thats nothing new.
Luckily they are pretty uneducated and inept.
And you will not find me explaining and discussing HOW one could get things like this working, not me and not those others who have a clue. So these musings will be left to those who don´t know and thats good this way.

PS: And to those who never get it right, it is a COMBUSTION engine in your car not an EXPLOSION engine. Got it? The gasoline does not explode but burns in a controlled manner. Explosion of the fuel is called "knocking" and is to be avoided by all means as it ruins the motor.



[Edited on 2-7-2007 by Organikum]




Restrict alcohol and Tobacco.
Legalize everything else.
Mandatory LSD for politicians and Franklyn.
View user's profile View All Posts By User
tito-o-mac
Hazard to Others
***




Posts: 117
Registered: 30-6-2007
Member Is Offline

Mood: No Mood

[*] posted on 2-7-2007 at 02:13


Here we have it, a closed chapter. As Organikum has said it, neither of us should want to know the theory behind such a unfeasible feat, nor shall we continue the endless arguement on the theories, the end remains a mystery no one will know...

[Edited on 2-7-2007 by tito-o-mac]
View user's profile View All Posts By User
Organikum
resurrected
*****




Posts: 2228
Registered: 12-10-2002
Location: Europe
Member Is Offline

Mood: fluffy!

[*] posted on 2-7-2007 at 03:19


I tell you a story from a long long time ago, before the internet and before electronics and plans were so easily available. I am an old fart,

Long long ago Organikum was member of some civil resistance against nuclear armament and such things. And we did not only demonstrate and hold hands. No, no. For special occasions we resorted to other means of direct action and that with good success.
Then we sat together, mostly students and pupils and workers from social professions, almost nobody skilled in something useful and know what? We came up with many ideas in a short time. We spent hours and hours not searching for ideas to wreck havok but to work out ways to do our thing WITHOUT hurting anybody, as violence against people, causing harm to somebody not involved was completely out of question.
It is so easy to flatten a pylon, but it is hard to figure out how to do it in a way which makes sure nobody gets hurt, no traffic lights go out during rush hour, no hospitals are cut off etc. And our tools were no explosives but not more then hacksaws and stuff. Thats enough.

And now we have some idiots who want exactly this:
Hurting as many people as any possible.
And they are not able to get anybody?
But somebody gave them plans for how to make a wireless ignition from a mobile.
And somebody gave them plans to make a bomb from propane and gasoline which does not work.
And they went and did it.
And got immedeately discovered, their names are known and they are hunted down now.

Something stinks to heaven here.

This is not about politics.
This is about my youth, about not working explosive devices and about our freedom which is on stake.

regards
/ORG

PS: An industrial society is not to protect. An industrial society is always vulnerable. People who spend their time searching and publishing ways how to do big damage to a country and the people are criminal minds who are in dire need of some professional help preferably in a closed institution.

[Edited on 2-7-2007 by Organikum]




Restrict alcohol and Tobacco.
Legalize everything else.
Mandatory LSD for politicians and Franklyn.
View user's profile View All Posts By User
Boomer
Hazard to Others
***




Posts: 190
Registered: 11-11-2005
Member Is Offline

Mood: No Mood

[*] posted on 3-7-2007 at 04:49


Did someone verify the "second degree burns from over a mile away" statement? Sounds like media hype, but wait!

I just calculated the energy of 18 railcars each holding 70 metric tons of LPG (at approx. 85 tons total per railcar). Came up with 1260 tons. At 42.000 kJ/kg for LPG and 4000 for TNT, that's 13 kilotons QED.

We better look out for Bin Laden trying to get a drivers licence, no need to learn flying a jet.
View user's profile View All Posts By User
Organikum
resurrected
*****




Posts: 2228
Registered: 12-10-2002
Location: Europe
Member Is Offline

Mood: fluffy!

[*] posted on 3-7-2007 at 06:21


Quote:
Originally posted by Boomer
.....
We better look out for Bin Laden trying to get a drivers licence, no need to learn flying a jet.
Good one. Reminds me somehow on the old german joke (which brought one into a concentration camp instantly in these bad days): "Der Führer war ein armes Schwein, er hatte keinen Führerschein!" ;)
Referring to the fact that Adolf Hitler ("Der Führer") had no driverslicence which in german aciidentially is called "Führerschein".

Completely off topic. Sorry.




Restrict alcohol and Tobacco.
Legalize everything else.
Mandatory LSD for politicians and Franklyn.
View user's profile View All Posts By User
 Pages:  1  

  Go To Top