Posted on 06/29/2007 1:42:54 PM PDT by HarmlessLovableFuzzball
The “patio gas” bomb defused in Haymarket would have generated a fireball the size of a house and a shock wave spreading out over a diameter of at least 400 yards, explosives experts said today.
The propane cylinders and petrol used in the device would have triggered a huge conflagration, as well as causing shrapnel and blast injuries from the exploding car chassis and the nails packed around the bomb, according to Hans Michels, Professor of Safety Engineering at Imperial College, London.
Just one 13kg propane canister — the type sold by Calor under the brand name “Patio Gas” — would release a highly flammable cloud of vapour that would spread over an area of 50 to 60 cubic metres before igniting into a still larger fireball, he said.
“The vapour cloud from one cylinder would fill the order of a big room, and when it ignited the effect would be even bigger,” Professor Michels said. “In addition to the power of the explosion and the shrapnel, you would get a fireball the size of a small house.”
As several propane or butane cylinders were recovered, the volume of the fireball would have been greater still, though it is impossible to calculate the size without knowing how much gas would have been involved.
Professor Michels, who has been an expert witness in explosives trials, said that although the police did not say whether high explosives were found in the car, another charge would probably have been used to ignite the petrol and gas.
An initiator such as triacetone triperoxide or TATP could have been used to detonate a main charge, such as the flour and hydrogen peroxide mixture allegedly used in the failed attacks of July 21, 2005. This would have blown up the car, scattering nails and shrapnel, as well as igniting the petrol and puncturing the gas cylinders.
The gas-fuelled fireball would have followed, though the timing of ignition would have affected the ultimate extent of the blast. It is possible that the petrol was intended as the main charge, but if so this would have resulted in a smaller explosion than if high explosive had been used.
The original explosion would have had to be large to penetrate the propane canisters, which are designed to withstand high-speed traffic accidents and fires.
Professor Michels said: “It is almost certain that the explosive device itself would have been sufficiently powerful not to just fragment the gas cylinders, but to destroy the car and possibly the front of buildings, with missiles, shrapnel, nails and burning petrol flung at very high velocity in the wake of the shock wave and the whole surrounded by a massive fireball resulting from the instantly evaporated and exploded propane and/or butane.
“It is also likely that the source of ignition and the explosive that should have set off the device was of the home made type, consisting of household materials now most commonly used by terrorists.”
Other experts suggested that the total blast could have been bigger still, depending on how many propane cylinders ignited and on whether high explosive was also used.
Andy Oppenheimer, editor of Nuclear, Biological and Chemical International, said the blast radius could have been anything from 200 years to half a mile. “It would have been a devastating explosion,” he said.
“With that amount of petrol and an unknown quantity of pressurised gas, the blast would have been about 200 yards. If high explosive was involved, the blast could have reached half a mile.
“Hundreds of people could have been injured if they had been in the area at the time. The knock-on effects of breaking glass are particularly devastating, for example.
“This would have been an explosion on the scale of those seen in the Middle East, although not as big as some that have been seen in Baghdad recently.”
The recovery of the intact bomb will also help forensic scientists to trace the bomb-makers, Professor Michels said. Propane cylinders carry a serial number which can be used to find the point of sale, and isotopic analysis could be used to trace any flour used in the main explosive charge.
Propane cylinders contain liquified propane, a volatile hydrocarbon, which would rapidly be transformed into a gas occupying 200 to 400 times the volume when released. This would mix with between 15 and 20 times that volume of air to produce an inflammable vapour cloud.
Brian Baker, director of the Association For Petroleum And Explosives Administration, said: “Propane is liquefied petroleum gas and patio heater gas is usually 97 per cent propane. Cylinders of this type of gas are readily available to the public and can be bought in places such as petrol stations and iron monger in particular.
“Propane is heavier than air when released, highly flammable and easy to ignite. When released in to the atmosphere and only a small amount is a required to cause an explosive condition and this is worse in a confined space when subject to an ignition source. Its explosive properties mean that 10 litres of the gas is equivalent to 2770 litres of flammable gas and air mix. There are controls on using this type of gas and this is why the industry gives lots of safety advice about use.”
...200 years...yeah that's devastating!
...it blowed up REAL good!
Methodists from Phoenix?
= =
Yeah, they were having a real row
with the . . . uhhh . . . the . . . uhhhh
Amish from the hills.
Evidently a horse bisquit went splat on a white Mercedes in the wrong place at the wrong time and they were off and running.
Of course, it took the Amish some time to get the 2 Mercedes in place with their plow teams.
STTM [Sar To The Max]
“It is obvious that if the device had detonated there could have been serious injury or loss of life.”...
= = =
Aparently not OBVIOUS enough . . .
given the genetic Chamberlains rushing to appeace and kiss Jihadi rears over there.
Isnt it time to go tit for tat for each incident? I would end the DOLE tonight and close down the beehives tomorrow.
LOL!
Our dear and true friends, the Brits, might want to reconsider their benign tolerance of Islamic extremism. It’s really not sophisticated to sit idly by while suicidal nut cases plot mass murder; it’s equally suicidal and serious negligence for the government.
“I’m starting to get the impression that these people aren’t at all concerned about their carbon footprint.”
Doesn’t matter, the lefties still love ‘em anyway/s
I’m starting to get the impression that these people aren’t at all concerned about their carbon footprint.
= =
Glad I wasn’t drinking any beverage over this college keyboard! LOL.
Methinks they’d ignite all the carbon in the planet even if it meant their own extermination . . . just out of blind spite.
Isnt it time to go tit for tat for each incident? I would end the DOLE tonight and close down the beehives tomorrow.
= = =
But you don’t understand. You’re not compassionate and sensitive enough.
THAT would mean that the good guys want to SURVIVE and act SANE! We can’t have that! The WEST HAS TO BE SUICIDAL!
THE PUPPET MASTERS HAVE DECREED IT!
And the Pied Piper pipes on . . . and the lemming adults follow lock-step while the children shake their heads.
STTM
“That cop who took the cell phone from the first vehicle is more of a hero than anybody knows”
Execellent point, HOA. God Bless him/her.
This is something I've been trying to get clarification on.
I wanted to find out the time and date of the calls they report, to know if they were called after the driver ditched the car, of if they were called before this to test device before the trigger went live.
As they were most likely using a clean prepaid cellphone with no history, "two missed calls" on the screen may not reveal the whole picture without the specifics.
If anyone has more info, please fill me in.
~snip~
“British police have a “crystal clear” picture of the man who drove the bomb-rigged silver Mercedes outside a London nightclub, and officials tell the Blotter on ABCNews.com he bears “a close resemblance” to a man arrested by police in connection with another bomb plot but released for lack of evidence. Officials say the suspect had been taken into custody in connection with the case of al Qaeda operative Dhiren Barot (pictured), who was convicted of orchestrating a vehicle bomb plot involving targets in London, New York, Newark, N.J. and Washington, D.C.
~snip~
U.S. and British law enforcement officials tell ABC News it is increasingly clear Friday’s bomb plot in London involves multliple vehicles, and is described by a senior official as a “terror plot involving lslamic extremists.”
http://blogs.abcnews.com/theblotter/2007/06/terror-plot-inv.html
flour and hydrogen peroxide?????
I don't, USF. I saw the report posted here earlier that the phone had been called twice, but that article gave no details as to what that report was based on.
“the blast radius could have been anything from 200 yards to half a mile. “It would have been a devastating explosion,” he said”....
That’s pretty big. And to have two vehicles (maybe more?)... Fuel Air....
The flammable (explosive) limits for propane are 2.3 to 9.5%. If there was “too much” propane no explosion. If you were in a room with 15% propane and lit a match, nothing would happen! (Well, you’d pass out from breathing all the propane).
The intent of the designers may have been a vapor explosion, but it takes some careful design to actually get one. The vapor must be mixed with air so that the above limits are met, then set off with multiple sources.
The device would have made a big fire for absolute certain, but the huge vapor explosion is speculation.
My intent here is not to make light of the situation, but the “journalist” is inflating the magnitude of the threat unless he has some detailed information on the car bomb’s design, which has been labeled “crude”. The professor quoted in the article does not even know if there was any high explosive in the car, or a detonator, yet he assumes huge FAB- type explosions.
OK, if it's really Islamofascists who are behind this as they are hinting, and if we are to believe them, we now have a whole new perspective on the situation.
"Show me just what Mohammed brought that was new, and there you will find things only evil and inhuman, such as his command to spread by the sword the faith he preached." - Manuel II Palelologus
Fuel-oxidiser. They don’t mean the 3% drugstore peroxide.
Pure hydrogen peroxide (not the 3% stuff in the drug store) is nasty stuff that decays to water and pure oxygen. Mix pure oxygen with something flammable and powdered like flour and your get a big boom.
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