Did Eric and Dylan understand BLEVE?

Everyone knows that Columbine was supposed to be a bombing rather than a shooting. We also know that Eric and Dylan constructed BLEVE devices. This is a device where a flammable material (such as gasoline) is ignited to heat a metal propane tank until it explodes.

However, did Eric and Dylan realize that BLEVE was actually two explosions, the first a fireball of igniting gasoline, and the second the explosion of the propane (or of the tank itself, depending on the safety valve)?

Did they understand that it takes several minutes after the fire starts for the valve to open and release propane, and several minutes after that for the pressure to build to the point that it creates a huge explosion?

I want to say yes, they understood. After all, they built them.

But their plans (wait by hill, charge through school) seem to suggest that they thought it would all go up at once. Additionally, Eric goes running up the cafeteria steps shortly after a gasoline ignition, suggesting that he thought it was going to go all at once.

In my mind, this is a big question for understanding their behavior that day. I have more thoughts but I'll save them.

The bombs are one topic/debate that still drive me insane to this day and always have since I started researching Columbine. I do not think that Eric knew that the fire had to start, heat the tanks up for 20 minutes or so and THEN the tanks would explode. If they knew this, wouldn't they have realized that within seconds of that fire starting the sprinkler system would turn on and put the fire out? Preventing the tanks from heating up and exploding?

They planned this for over a year. And they didn't once think of this?

If they understood BLEVE, they'd have gotten the 250/500+ kill count they were aiming for and possibly more.

Everyone in the school that day should've been thankful that E and D didn't have that little bit more of experience.

-eulogy- wrote:

If they understood BLEVE, they'd have gotten the 250/500+ kill count they were aiming for and possibly more.

Everyone in the school that day should've been thankful that E and D didn't have that little bit more of experience.

Not true.

A BLEVE explosion happens in several stages, which take several minutes to unfold. First the gasoline ignites, then (depending on the propane tank) a safety valve may open (releasing propane, which will slowly burn), and finally, the propane tank itself might explode, depending on other factors.

If Eric's and Dylan's bombs had worked, they would not have killed anyone, because they would have first created a gasoline ignition, which would have burned for several minutes before igniting any propane at all. This would have given everyone time to leave.

Look at 0:01 in this video of a BLEVE system. It shows the first ignition and then the final one at 1:26: [You must be registered and logged in to see this link.]

11:46:11 camera time of this video corresponds to 0:01 in the above: [You must be registered and logged in to see this link.]

You can see that if Eric and Dylan's bombs had worked as designed, they would have first produced only a fireball, and not an explosion that threatened the lives of most students.

My question was: did Eric and Dylan know it was a multistage process that would take several minutes?

Jenn wrote:

They planned this for over a year. And they didn't once think of this?

There is a lot of evidence that they didn't understand it. The 300 body count prediction, Eric running up the stairs as soon as the thing lights on the cafeteria tape, all of that makes it look like they thought it would all go at once.

But is there any evidence that they did understand it, and realized it would take about ten minutes to go?

BLEVE does not contradict their initial plans. The first fireball would have sent every student in the cafeteria running for the nearest exits, including the doors covered by Eric and Dylan. So the "wait outside" plan is consistent with a two-step BLEVE.

There is other evidence, too. After the attack begins, Dylan goes in the cafeteria. Was he looking to see if the first ignition had happened? After they enter, they lob a bomb into the cafeteria at 11:28. Then they go into the library. While there, they tell people that the library is going to blow up, killing everyone. Did they think they had ignited the gasoline with the 11:28 pipe bomb, and that the propane was going to blow any minute, possibly while they were in the library (when Dylan tells Eric to shoot Bree Pasquale, Eric says no, telling him that the library is going to blow up anyway)? They return to the cafeteria and try to blow it up again at 11:38. Then they leave again and return after a 5-6 minute interval. At this moment, they actually ignite two containers of gasoline, but of course it doesn't heat the propane. They run out, but return again after another 5-10 minute interval, finally leaving at noon for good.

The constant return to the cafeteria at roughly ten-minute intervals may have been evidence that they knew it would take a while to go.

If they did understand BLEVE, we have to conclude that their wandering was not "random." They were waiting out the ten-minute intervals they thought it would take for the thing to go.

lasttrain wrote:

Jenn wrote:

They planned this for over a year. And they didn't once think of this?

There is a lot of evidence that they didn't understand it.  The 300 body count prediction, Eric running up the stairs as soon as the thing lights on the cafeteria tape, all of that makes it look like they thought it would all go at once.  

But is there any evidence that they did understand it, and realized it would take about ten minutes to go?

BLEVE does not contradict their initial plans.  The first fireball would have sent every student in the cafeteria running for the nearest exits, including the doors covered by Eric and Dylan.  So the "wait outside" plan is consistent with a two-step BLEVE.

There is other evidence, too.  After the attack begins, Dylan goes in the cafeteria.  Was he looking to see if the first ignition had happened?  After they enter, they lob a bomb into the cafeteria at 11:28.  Then they go into the library.  While there, they tell people that the library is going to blow up, killing everyone.  Did they think they had ignited the gasoline with the 11:28 pipe bomb, and that the propane was going to blow any minute, possibly while they were in the library (when Dylan tells Eric to shoot Bree Pasquale, Eric says no, telling him that the library is going to blow up anyway)?  They return to the cafeteria and try to blow it up again at 11:38.  Then they leave again and return after a 5-6 minute interval.  At this moment, they actually ignite two containers of gasoline, but of course it doesn't heat the propane.  They run out, but return again after another 5-10 minute interval, finally leaving at noon for good.

The constant return to the cafeteria at roughly ten-minute intervals may have been evidence that they knew it would take a while to go.

If they did understand BLEVE, we have to conclude that their wandering was not "random."  They were waiting out the ten-minute intervals they thought it would take for the thing to go.

I guess this is all a matter of opinion, really. From what I've read about the bombs, and believe me, that has been a lot. It is the one thing I still obsess about. Mainly because, there are so many things about them I don't understand. I just think to myself, "what were they thinking" or "how did they think this was going to work?" And I try to think how they would have been thinking.

But back to your question. I have never read any evidence one way or the other that they knew or didn't know that for the bombs to blow up, there was a process. It is my personal opinion, that Eric thought that the alarm clocks would ring, the battery would cause a spark that would ignite the cannon fuse which would travel down to the gasoline can, it would start a fire and they would automatically explode. That they thought there would be this huge explosion that would kill just about everyone in the cafeteria and that they would stand outside and shoot the remaining students/teachers that ran out after the explosion.

You make some great points though. But honestly, I think that they thought it would be one big blast. I think they kept going back down to the cafeteria to try and get the bombs to explode. It seems to me, that is all Eric really cared about, was getting those bombs to explode.

IF they knew it was process, they would have known that it never would have worked because once the fire started, fire alarms would have went off, the sprinklers would have turned on and the fire would have been put out. Never giving the fire enough time to heat up the propane tank.

So, with that being said, I have come to the conclusion that they did not know. Again, this is just what I think, it doesn't mean I am right or wrong.

Quote :

IF they knew it was process, they would have known that it never would have worked because once the fire started, fire alarms would have went off, the sprinklers would have turned on and the fire would have been put out. Never giving the fire enough time to heat up the propane tank.

My best guess would be that they simply didn't account for the sprinklers. When you read Dylan's school planner with the schedule for the attack it reads:


Walk in, set bombs at 11:09, for 11:17

Leave,

Drive to Clemete Park.  Gear up.

Get back by 11:15

Park cars. set car bombs for 11:18

get out, go to outside hill, wait.

When first bombs go off, attack.

have fun!  


The thing is: we don't know if Dylan meant that the car bombs were the second bombs, or if the initial fireball was considered the "first bombs" and the propane tank explosion was supposed to come afterward. There's probably more evidence for the first, but if the latter were true then they did understand how BLEVE's worked.

What that sounds like to me is, they set the first bombs(in the cafeteria) to blow up at 11:17 and then after it blew up, students would be running out to the parking lot, where one minute later their car bombs would blow up. And I think they were hoping the car bombs would kill whoever ran out into the parking lot.

Think about this. How much sense would it make to have the car bombs blow up at 11:18 while everyone was still in the school? Wouldn't it make much more sense that they wanted their car bombs to explode a minute after the first bombs were meant to explode at 11:17?

Again, taking all of this into consideration, I still do not believe they knew there was a process to blow up those propane tanks. I believe they thought once they ignited, they would blow up.

A side note: Does anyone know if BLEVE was even mentioned in the "cookbook" that Eric got the idea for the propane bombs?

lasttrain wrote:

-eulogy- wrote:

If they understood BLEVE, they'd have gotten the 250/500+ kill count they were aiming for and possibly more.

Everyone in the school that day should've been thankful that E and D didn't have that little bit more of experience.

Not true.

A BLEVE explosion happens in several stages, which take several minutes to unfold.  First the gasoline ignites, then (depending on the propane tank) a safety valve may open (releasing propane, which will slowly burn), and finally, the propane tank itself might explode, depending on other factors.

If Eric's and Dylan's bombs had worked, they would not have killed anyone, because they would have first created a gasoline ignition, which would have burned for several minutes before igniting any propane at all.  This would have given everyone time to leave.

Look at 0:01 in this video of a BLEVE system.  It shows the first ignition and then the final one at 1:26: [You must be registered and logged in to see this link.]

11:46:11 camera time of this video corresponds to 0:01 in the above: [You must be registered and logged in to see this link.]

You can see that if Eric and Dylan's bombs had worked as designed, they would have first produced only a fireball, and not an explosion that threatened the lives of most students.

My question was: did Eric and Dylan know it was a multistage process that would take several minutes?  

That ain't the damn point.

Everyone there on 4/20 were blessed that Dylan and Eric weren't just that little bit more knowledgeable about bomb making.

More evidence:

3/15

They then talk about Brandon Larson and how "you will find his body". The boys talk about the large propane bombs they plan to use on the unsuspecting students in the school cafeteria. They discuss bombs and two bags of "propane and napalm", and mention Mr. Stevens and the shotgun.


3/18

Eric and Dylan say that there are "only two weeks left, and one more weekend" and that "it is coming up fucking quick". They say the "napalm better not freeze at that certain person's house". They talk about "Chris' pizza's house" like they're trying to disguise a name and discuss "Yoshi" in a negative way. They say that they need a "lot more napalm" and may just use "gas and oil". They express concern that it will be tough, and opening the zipper may make it go off. They say they need some "back-ups". They talk about how the sprinkler system may "put out a fire" and Eric says he should possibly keep the battery out of the device, set the bag, put it in and leave so it doesn't "blow up in the commons".


They say they need "devices" for the propane tanks and they need more "bomb holders". Eric says they need to go to Radio Shack because he heard they had a "thing to increase the voltage" through a clock and speaker, igniting a solar igniter.

What are they talking about here?

lasttrain wrote:

BLEVE does not contradict their initial plans.  The first fireball would have sent every student in the cafeteria running for the nearest exits, including the doors covered by Eric and Dylan.  So the "wait outside" plan is consistent with a two-step BLEVE.

This is what I think also. Fits with their setting the car-bombs to explode so soon afterward. The big car-bomb explosions would then take place after LE and FD arrived. It's pretty obvious they were waiting for a propane bomb to go off after Dylan ignited one partially with a Molotov cocktail. Yes Eric runs away but anyone would run from even the partial detonation -- even if they were suicidal and knew about BLEVE because it is just an instinctive thing. The telling element is they waited several minutes before coming back down to see the sprinklers had put out the initial fire.    

I just think the boys were too smart and technically proficient to not know about BLEVE... That said I also believe they romanticized and over-estimated their capacities...

gustopoet wrote:

lasttrain wrote:

BLEVE does not contradict their initial plans.  The first fireball would have sent every student in the cafeteria running for the nearest exits, including the doors covered by Eric and Dylan.  So the "wait outside" plan is consistent with a two-step BLEVE.

This is what I think also. Fits with their setting the car-bombs to explode so soon afterward. The big car-bomb explosions would then take place after LE and FD arrived. It's pretty obvious they were waiting for a propane bomb to go off after Dylan ignited one partially with a Molotov cocktail. Yes Eric runs away but anyone would run from even the partial detonation -- even if they were suicidal and knew about BLEVE because it is just an instinctive thing. The telling element is they waited several minutes before coming back down to see the sprinklers had put out the initial fire.    

I just think the boys were too smart and technically proficient to not know about BLEVE... That said I also believe they romanticized and over-estimated their capacities...

I'm not sure I agree with you on them being "too smart". If they were really all that smart, wouldn't they have tested out this idea up in the mountains? I don't think they were that smart at all. I think they were young, naive and stupid. They really had no idea what they were doing. They got a recipe out of The Anarchist Cookbook and just assumed it would work, without testing it.

Don't get me wrong, I am not saying I think they were unintelligent and stupid as a whole. I am just referring to the bombs. I think they were very smart in other aspects, just not their bomb making skills.

Jenn wrote:

Don't get me wrong, I am not saying I think they were unintelligent and stupid as a whole. I am just referring to the bombs. I think they were very smart in other aspects, just not their bomb making skills.

Well you're right they were not good at building bombs. I still think it's likely they knew about BLEVE. Their timetables and actions seem to support the idea as does their OCD in regard to technical things. But I guess we'll never know for sure.

One thing that stands out in my mind is Eric telling someone at Blackjack that he had 15-16 propane tanks and wanted more. Nothing even close to that amount was found after the attack. Can we be sure they never tested one of the propane bombs?

gustopoet wrote:

Jenn wrote:

Don't get me wrong, I am not saying I think they were unintelligent and stupid as a whole. I am just referring to the bombs. I think they were very smart in other aspects, just not their bomb making skills.

Well you're right they were not good at building bombs. I still think it's likely they knew about BLEVE. Their timetables and actions seem to support the idea as does their OCD in regard to technical things. But I guess we'll never know for sure.

One thing that stands out in my mins is Eric telling someone at Blackjack that he had 15-16 propane tanks and wanted more. Nothing even close to that amount was found after the attack. Can we be sure they never tested one of the propane bombs?  

If Eric had tested the bombs and knew about BLEVE, then he'd know the bombs would have to heat up before explosion. IF he knew this, why was he worried that the bomb would blow up while unzipping the bag and setting the timer?

gustopoet wrote:

Jenn wrote:

If Eric had tested the bombs and knew about BLEVE, then he'd know the bombs would have to heat up before explosion. IF he knew this, why was he worried that the bomb would blow up while unzipping the bag and setting the timer?

Good point. Maybe he was worried that the pilot-blast would be enough to cause injury and totally screw up their plans?

It's possible, I suppose, but I still think, from everything we know, that they did not know about BLEVE. They set the timers to go off at 11:17 and that is when they expected them to blow up. (The time which Eric estimated there would be the most people in the Cafeteria). He was expecting an explosion, not a fire that had to burn for 20 minutes before exploding.

I'd still love to know, exactly how this alarm clock was going to start a fire? It's been nearly 2 years and I still haven't figured that one out yet.

Jenn wrote:

They set the timers to go off at 11:17 and that is when they expected them to blow up. (The time which Eric estimated there would be the most people in the Cafeteria). He was expecting an explosion, not a fire that had to burn for 20 minutes before exploding.

They said they thought that the sprinklers might put out the fire, so I think they did understand BLEVE. Another reason to think they understood is that they had to know the clocks were wired into the gas cans NOT directly to the propane tanks so there had to be some sort of delay. They had to know it wouldn't be instant. They may not have been sure of how long, but... I think they knew there would be a delay.

One last thing: if they thought the propane bombs were going to go off instantly, blow out the support pillars and collapse the library -- what survivors would be left to shoot at? The survivors would have been elsewhere away from where the boys positioned themselves. OTOH if they thought the first fireballs would send people running they were in a good position to put escaping students in a 9mm crossfire. The students would be forced to run back toward/in school.

Then when the big bombs went off...they charge in and clean up w/ shotguns.

gustopoet wrote:

Jenn wrote:

I'd still love to know, exactly how this alarm clock was going to start a fire? It's been nearly 2 years and I still haven't figured that one out yet.

--POST REMOVED--

Where did you get this from? The description of how to make the clock work? I looked on the internet and couldn't find it anywhere! Or is this just what you guessed would have to happen?

gustopoet wrote:

Jenn wrote:

I'd still love to know, exactly how this alarm clock was going to start a fire? It's been nearly 2 years and I still haven't figured that one out yet.

--POST REMOVED--

Gee, THANKSss for the directions..  ;)

gustopoet wrote:

Jenn wrote:

Don't get me wrong, I am not saying I think they were unintelligent and stupid as a whole. I am just referring to the bombs. I think they were very smart in other aspects, just not their bomb making skills.

Well you're right they were not good at building bombs. I still think it's likely they knew about BLEVE. Their timetables and actions seem to support the idea as does their OCD in regard to technical things. But I guess we'll never know for sure.

One thing that stands out in my mind is Eric telling someone at Blackjack that he had 15-16 propane tanks and wanted more. Nothing even close to that amount was found after the attack. Can we be sure they never tested one of the propane bombs?

Their obsessive disorder obviously didn't help them much since their bombs took zero victims, and if they tested the bombs nobody is ever going to find out.

InFiNiNcEX5 wrote:

gustopoet wrote:

Jenn wrote:

I'd still love to know, exactly how this alarm clock was going to start a fire? It's been nearly 2 years and I still haven't figured that one out yet.

--POST REMOVED--

Gee, THANKSss for the directions..  ;)

Yea, I might have to delete this post before some complains saying I am allowing bomb making directions on my forum.

Oh and no, Eric and Dylan wouldn't have known anything about these sophisticated bombs and equipment. They bought propane tanks for Godness sake and couldn't even get them to ignite or blow. If they knew the ins and outs of "BLEVE" then their plan would have been a success.

Ivan wrote:

If they knew the ins and outs of "BLEVE" then their plan would have been a success.

They could know about BLEVE and still make crappy bombs. The fact is, in the reading I've done on the propane bombs indicates they would have never functioned like Eric and Dylan envisioned and they had almost a zero chance of ever exploding under any circumstances. It's evidently not that easy to explode a propane tank.

Ivan wrote:

Their obsessive disorder obviously didn't help them much since their bombs took zero victims, and if they tested the bombs nobody is ever going to find out.

True enough.

Ivan wrote:

Oh and no, Eric and Dylan wouldn't have known anything about these sophisticated bombs and equipment.  

The circuitry and construction are actually frighteningly simple.

gustopoet wrote:

Ivan wrote:

Oh and no, Eric and Dylan wouldn't have known anything about these sophisticated bombs and equipment.  

The circuitry and construction are actually frighteningly simple.

It wasn't "frighteningly simple" for Dylan and Eric since they had to actually shoot the propane bombs in order for them to ignite. The circuitry is probably the most difficult part in bomb design and creation. Everything needs to be exactly right or else it won't work, it's applicable to several things including household utensils that cannot function properly due to an error in their circuitry or even gaming systems.

Construction of the bombs would be easier if you know what you are doing.

Ivan wrote:

It wasn't "frighteningly simple" for Dylan and Eric since they had to actually shoot the propane bombs in order for them to ignite.  

The circuitry to wire the clock to the gas tanks is very simple. It actually involves rewiring only a single wire. That doesn't mean that I'm saying Eric and Dylan were good at making bombs; I'm not. The device they were trying to construct was not sophisticated; it was simple. They still botched it.

Whether they were working with simple or complicated devices is a separate question from whether they understood BLEVE, which is itself a separate question from whether or not the propane bombs as designed could have worked at all. I think it's unlikely that the bombs could work. From what I understand there are valves built into the propane tanks that make them very hard to detonate. Shooting the tank would not ignite it. But Dylan's Molotov cocktail set off the gas-tank that was attached to the propane tank which was put out by the sprinklers.

It's obvious the boys were bad bomb-makers. The pipe-bombs mostly failed as well due to the kind of powder they used, which burned too slow.

So, yes you are right they were not skilled at making bombs. And this could be a circumstantial indication that they didn't understand BLEVE.

Some info on BLEVE and propane bombs:

"Propane tanks do not explode. They do not implode and nor do they rupture or come apart on their own. In fact, bringing a propane tank to the point of "explosion" is a tremendously difficult and time consuming task that's not as simple as most people think. Many people believe that a propane tank "explosion" can occur with the slightest of ease. This is not the case whatsoever and people should understand that a propane tank, operating under normal circumstances will not explode or rupture. Safety devices and mechanisms are in place to prevent explosions, accidents and propane tank ruptures or breaches."


"A propane tank BLEVE will occur when the container is subject to extreme heat, such as in a fire. While the tank is being heated, the liquid propane inside is being heated causing it to expand. The safety relief valve will open allowing pressure to vent to the outside atmosphere. If the pressure inside the tank grows to a level exceeding that at which the safety relief valve can expel it from the tank, the propane tank may rupture. If flames or a source of ignition is present, the propane will ignite resulting in an explosion. It's important to know that a BLEVE will occur only if the conditions are right, such as being subject to continuous flame impingement over a period of time. The possibility of a propane tank explosion (BLEVE) is extremely remote."

[You must be registered and logged in to see this link.]

One more thing about BLEVE: if the boys didn't understand it, then why did Eric stay so far away when he shot at the propane bomb? If they thought the tank would blow up all at once and they were suicidal, then why not walk RIGHT UP to the tank, shoot it, and be sure of hitting it?

OTOH if you thought the pilot-blast would merely cause injury not death, you would stay back from the initial blast.

Yet another factor that makes me think Eric and Dylan knew about BLEVE is the mechanism of dry-ice bombs. Eric and Dylan are known to have made and detonated dry-ice bombs. The way that dry-ice bombs work is similar to the propane bombs with a slow build of pressure.

From wikipedia:

"Dry ice bombs are commonly made from a container such as a plastic bottle, water, and dry ice. The bottle is filled about quarter full of water. Some broken chunks of dry ice are added and the container is shut tightly. As the solid carbon dioxide warms inside a bottle, it sublimates to a gas. The pressure inside the bottle increases as the quantity of gas increases with limited room to expand. Bombs will typically rupture within 30 seconds to 30 minutes, dependent largely on the temperature of the air outside the bottle.

Dry ice bombs have some serious risks:
Premature explosion. Burst pressure can occur within seconds, injuring the handler.
Dry ice is very cold: −78.5 °C (−109.3 °F). The explosion can carry shards of dry ice that had not sublimed.
The shock wave can be extremely loud and hearing damage can occur even at substantial distances.
The blast can propel fragments of the container at very high speeds causing cuts and puncture wounds.
Added shrapnel such as nails, marbles, and metal fragments can cause blunt force trauma to the body.
Dud bombs which fail to explode are a major safety problem. They cannot be left, yet cannot be safely approached. Unexploded bombs can be shot or otherwise ruptured from a safe distance. Injuries are common, with glass bottles in particular posing a risk of serious injury or death."

I think this clearly shows that the boys were treating the propane bombs throughout the attack like they expected them to function similarly to dry-ice bombs.

best video I cold find explaining BLEVE (Boiling Liquid Expanding Vapor Explosion):

[You must be registered and logged in to see this link.]

What if Eric had done a practice test beforehand ? What if it was successful?
Just say Eric went up into the mountains and used a smaller propane tank for the test?
He may have been afraid of using a large tank due to the size of the explosion which would occur and the massive noise it would create. He obviously wouldn't want to attract attention to himself.

Just say the tank was a small one that are used for cooking while camping out.
a 1 or 2 kg tank. It would heat up quicker and require less heat than the tanks that were used during the massacre. 

The test may have been successful and maybe Eric presumed that a larger propane tank would work too. If it took 5 minutes to blow a small tank ( i can only guess ) Eric may have believed that would apply to any size.

I find it hard to believe that ( during the 12 month planning ) Eric would just presume that a naked flame would cause a propane tank to immediately explode. He must have had some knowledge of the process and must have tested it in some way.
What do you think about this? 
Could Eric have tested a smaller tank and been successful in blowing it up?

rik75 wrote:

Could Eric have tested a smaller tank and been successful in blowing it up?

I think it is very likely for the following reasons:

1) Chris Morris describes the boys telling them about exploding a bomb in the mts that left a HUGE blast hole behind -- one that was way too big for a pipe-bomb to make.

2) Eric bought a lot more propane tanks than what were discovered.


They pretty much had to know about BLEVE at least to some degree because they wired the bombs and knew nothing was wired directly into the propane tanks.  I bet Eric spent a LOT of time researching bombs, not just the ones he could make and test, but bombs of all kinds.

Remember: even knowing about the technical aspects of bombs (or guns) is a power-totem for many people and not just disgruntled kids! So I think Eric was probably pretty serious about his technical knowledge of bombs.

If they were making and detonating dry-ice bombs at work it seems very likely to me that they tested a small propane bomb at some point. They may have done so even before they formally decided to carry out an attack on the school -- just for kicks.

gustopoet wrote:

rik75 wrote:

Could Eric have tested a smaller tank and been successful in blowing it up?

I think it is very likely for the following reasons:

1) Chris Morris describes the boys telling them about exploding a bomb in the mts that left a HUGE blast hole behind -- one that was way too big for a pipe-bomb to make.

2) Eric bought a lot more propane tanks than what were discovered.


They pretty much had to know about BLEVE at least to some degree because they wired the bombs and knew nothing was wired directly into the propane tanks.  I bet Eric spent a LOT of time researching bombs, not just the ones he could make and test, but bombs of all kinds.

Remember: even knowing about the technical aspects of bombs (or guns) is a power-totem for many people and not just disgruntled kids! So I think Eric was probably pretty serious about his technical knowledge of bombs.

If they were making and detonating dry-ice bombs at work it seems very likely to me that they tested a small propane bomb at some point. They may have done so even before they formally decided to carry out an attack on the school -- just for kicks.

I have been looking through the 11K again. 

 Pages 7689 - 8274 Bombs/1st responders/First aid/Weapons.

According to the reporting officer M Guerra : " A device with a clock timer pipe bomb and a propane tank was identified inside the Harris vehicle. I could see a clock timer and a two inch pipe bomb laying next to a propane tank. "

Also inside the car : 2 large black containers that were labeled " lane conditioner " believed to contain petrol.
2 five gallon petrol cans.
2 two gallon petrol cans.
2 one gallon petrol cans.
A white plastic gallon jug believed to contain a home made napalm substance. 
A 1 pint bottle of Clorox and a metal can of charcoal lighter.

Was the pipe bomb set up to blow up the propane tank?  

  INSTANT EXPLOSION! ! !


The report doesn't gone into a great deal of info regarding this.
If Eric wanted his car to instantly explode , why didn't he use the same method with the cafe bombs? 

You can't detonate a propane tank with a pipe-bomb. Everything they added to the propane-bombs was meant to keep a fire burning and/or cause immediate injury while the BLEVE was building up.

There is in fact no way to "instantly" detonate a propane tank. The boys wired the electric alarm clocks into solar-igniters that were wired into the gas-cans. The idea is that the alarm clock sends an electrical impulse to the solar-igniter which then causes a spark that detonates the gas-can which then causes a fire that causes the propane to boil. When the pressure builds to a high enough point, the propane tank will detonate. Under even the best circumstances, the propane tanks still have only a very slight chance of detonating.

The detonation can't be instant in any BLEVE device.

gustopoet wrote:

You can't detonate a propane tank with a pipe-bomb. Everything they added to the propane-bombs was meant to keep a fire burning and/or cause immediate injury while the BLEVE was building up.

There is in fact no way to "instantly" detonate a propane tank. The boys wired the electric alarm clocks into solar-igniters that were wired into the gas-cans. The idea is that the alarm clock sends an electrical impulse to the solar-ingiter which then causes a spark that detonates the gas-can which then causes a fire that causes the propane to boil. When the pressure builds to a high enough point, the propane tank will detonate. Under even the best circumstances, the propane tanks still have a very slight chance of detonating.

The detonation can't be instant in any BLEVE device.

I understand BLEVE ,i'm not sure how the pipe bomb comes into the equation ? I would like to know what was the purpose of having a PB sitting next to the propane? Was the PB expected to be detonated by the propane blast?

No, I think they were just adding as much as possible to the mix to make the fires hot enough and sustained enough to cause the BLEVE. They had a lot of pipe-bombs to spare... The pipe-bombs in the cafeteria propane-bombs were meant to injure as many people as possible when the pilot-blast went off. The ones left in the cars were just for added ooomph and kicks since they had quite a few more than they needed. The pipe-bombs would have been detonated by the initial gas-can explosion, or shortly thereafter would be my guess. They would pack added shrapnel.

sorry to bring up an old thread about this BUT

I have never believed that Eric/Dylan were planning on a BLEVE explosion for their cafeteria/car bombs.

I believe that they planned for there to be an 'instant rupture/explosion' of the propane tanks and everything else at the same time.

Of course that never happened but I am sure that is what they wanted to happen.

sorority, I agree with you, because Eric and Dylan never referred to a two-step explosion in their comments.

And when they were trying to detonate the bomb on surveillance camera they reacted as if they feared immediate global detonation.

But I'm just curious--is there any other evidence that's led you to this conclusion?

Bumping this thread since the topic has been a point of contention recently.

There is some initial plausibility in Guest's position, such as the gas can attached to the bomb, or the gas cans set haphazardly throughout the cars, and their starting fires but not having the propane tank go off in both the cafeteria or diversion. It does make sense for those to be prior to the bomb, not after.

But I'm more or less with sororityalpha, in that none of their actions make sense with the understanding that the bombs were going to cook for several minutes. Why ignore the sprinklers? Why have timers on it if you can't make it go off at a certain time? To echo lasttrain, shooting at the bomb was obviously meant to make it go off.  Also, they go for setting a fire after trying pipe bombs and shooting at it; they don't just set a fire. They don't wait around on the stairs or in the library for the bomb to cook.

I think what really seals it is the car bombs, if the cafeteria didn't already. Without the element of surprise those things seem pointless. I guess you can say the pipe bomb explosions in the mean time would be enough before the BLEVE went off, but it's still absurd to have a car light on fire and have everyone get away from it. Especially if intended for first responders, meaning a fire truck would be near by. Hard to disagree that cafeteria and car bombs that simply go off are ten times better than ones that cook. All their writings seem to suggest that. It's not like Dylan wrote "Set bombs for 11:16, then wait for ten minutes, HAHAHAHA"

Also, correct me if I'm wrong, but I don't recall pipe bombs being with the cafeteria bombs, rather only with the car bombs and diversions. And these they weren't going to ever see again. However, they throw pipe bombs into the cafeteria as soon as they enter. That seems to me significant.

So, my best attempt to reconcile what both sororityalpha (or me) and Guest is seeing, is that they thought if they could pierce the propane tank with a pipe bomb or bullet, then they thought that would make it soon to go off from the fire. It's certainly possible they just picked a gas bomb because they wanted a fiery explosion like Duke Nukem 3D rather than a big hole like OKC, and didn't know any more than that.