# I need an explosion to take place



## courtneyv (Sep 6, 2012)

I have a scenario in which I need a car to explode, where remains would be miniscule or hard to identify, and it needs to look like an accident. In my book a gasoline tanker hits the car (explained) and they go over a cliff. But actual cliffside explosions are rare. Is this enough to cause such an explosion? Do I need something additional to create one. I really want to avoid explosive devices or traceable incendiaries if I can.


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## j.w.olson (Sep 6, 2012)

Have a plane crash into it? Have it be a hollywood explosion? (Cars explode in movies just from driving off cliffs all the time.)
I can't actually help, as I know little in this area, but I'm posting mainly to find out the answer myself, when someone else gives it.


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## Potty (Sep 6, 2012)

The driver looses control and smashes into a petrol station.


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## Terry D (Sep 6, 2012)

Gasoline tanks on cars do not explode.  There isn't enough oxygen in a gas tank (even one which is mostly empty) to support an explosion.  If the tank ruptures exposing the gas to air and there is a source of ignition, then the fuel will burn very quickly, but, since in is not enclosed any longer, it will not explode with enough force to shred a car to the extent you are describing.  The gas tanker is the same situation -- lots of burning, but no explosion.  The burning associated with a gas tanker would be extensive enough to destroy everything but the steel components of the car, but things like the Vehicle Identification Number, the steel body panels and the frame would survive.

To completely destroy a car you would need a secondary explosive device.  A very powerful one.  Even after the Oklahoma City bombing, the VIN on the rental truck was still usable.


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## Bloggsworth (Sep 6, 2012)

If you happen to have a 5 kilotonne bomb handy, you might have miniscule remnants, but failing that... Timing mechanisms at the centre of terrorist bombs leave parts large enough for analysis, there is no way anything short of a small nuclear weapon is going to dismantle a cast-iron engine block to the extent that it would resemble a micro jigsaw puzzle. Planes impacting the ground at 1,000MPH leave readily identifiable pieces.


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## Sam (Sep 6, 2012)

Here's another thread on a related question: http://www.writingforums.com/research/118152-how-blow-up-vehicle.html

Terry pretty much said all I would have. Cars don't explode unless they're carrying something explosive. By itself, the fuel tank is not enough.


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## courtneyv (Sep 6, 2012)

Thanks. That's what I figured. If not an explosion, would this kind of crash cause on extensive fire, so that an ME  would have a difficult time identifying the remains? It's mostly the  bodies I'm concerned about. I'm trying to fake a death with a car crash  while killing people at the same time.


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## Terry D (Sep 6, 2012)

Oh, yes. A gasoline fueled fire could easily incinerate a body to the point of unrecognizability (is that even a word?).  There would still, probably, be enough DNA available from bone marrow, or tooth pulp, for a DNA identification.  Also dental records; prosthetic, or surgical implants would also survive.


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## Kevin (Sep 6, 2012)

Cars often catch fire. Once you get them lit, with all the synthetics like the seats, dash and the tires...even the hoses and insulation on the wiring, they'll burn for a long time.


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## courtneyv (Sep 6, 2012)

Thank you so much. That's helpful!


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## The Backward OX (Sep 7, 2012)

[The technician and the Commander have some final words in the well of the crew-deployment hatch.]

“You know your orders, 015TY?”

“Yes, sir. When we come in close to the blue planet, I open this door and seek a suitable target on which to test our new intergalactic incendiary device. Using the ship’s portable aiming mechanism, I transmit the device directly to the target.

“If all goes to plan – *‘KER-BLUEY!’* No more target.

“We return immediately to Worm Drive Seventy Seven, and no one on the blue planet will be any the wiser.”


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## Cran (Sep 7, 2012)

courtneyv said:


> Thanks. That's what I figured. If not an explosion, would this kind of crash cause on extensive fire, so that an ME  would have a difficult time identifying the remains? It's mostly the  bodies I'm concerned about. I'm trying to fake a death with a car crash  while killing people at the same time.


So, it's not the car, but the bodies which need to be reduced beyond identification? 
And it's a deliberate act, not an improbable accident - ruling out meteor strike or aircraft emergency landing on the highway; a handy tornado leading to an electrical substation or high voltage tower collapse; bridge collapse, temporary earthquake rift opening or landslide that buries everything for years? 

To go beyond any recoverable DNA is a tall order; how about switching the medical records so that the dentals and DNA match the found remains?


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## courtneyv (Sep 7, 2012)

All the bodies can be identified accurately, I don't care about that, but a child was removed from the car just before the accident. I need it to be believable (to readers and the general public in the story) that she was in the crash and died, even though there are no remains of her found. 

The killers have limitless connections, so they could put another child in the car as a replacement and even tamper with results. Is that necessary?


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## Cran (Sep 7, 2012)

courtneyv said:


> All the bodies can be identified accurately, I don't care about that, but a child was removed from the car just before the accident. I need it to be believable (to readers and the general public in the story) that she was in the crash and died, even though there are no remains of her found.


OK - narrowing down even further; that's good. So, for how long must the girl be presumed dead?

If downslope of the cliff is difficult enough terrain, with plenty of scree or talus (loose rocks and other accumulated detritus that collects at the base of cliffs and very steep slopes), and if the cliff is less than vertical, and the girl's body is not found, then there is the possibility that, during the vehicle's crashing descent, the girl or her body was thrown free and may be buried beneath the wreck and any recently disturbed talus, or may have landed in another part of the virtually inaccessible rubble. 

Search and rescue can be further hampered by another (conveniently arranged) rockfall or slide, turning the media and authorities away from the hunt for bodies and onto the more immediate task of rescuing the searchers. 

The more material that can fall to bury the evidence, the longer it will take to safely investigate the scene. Long enough, and other priorities will claim their resources; it becomes a cold case. 



> The killers have limitless connections, so they could put another child in the car as a replacement and even tamper with results. Is that necessary?


Only if "missing, presumed dead" is not enough for the time required.


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## dolphinlee (Sep 29, 2012)

Just to clear up a point in this discussion.

"In today's cars, the petrol tank is usually housed deep between strong lumps of steel. But the 1970s American small car, the Pinto, suffered from very bad design. As a result, it could burst into flames when it was hit from behind. First, the pipe that joined the petrol cap to the petrol tank would easily tear loose in a rear-end collision. Second, in such a collision, the petrol tank would get squashed against the differential - that big pumpkin of metal in the middle of the back axle. This meant that liquid petrol could spill out onto the ground. If a spark (from bare wires or from scraping metal parts) were to occur where the petrol vapour level was between 2% and 8%, the vapour would ignite and explode. About 500 people died, and another 400 were badly burnt, as a result of petrol fires caused by rear-end collisions in Pintos."

Exploding Car › News in Science (ABC Science)


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