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Message no. 1
From: Rand Ratinac docwagon101@*****.com
Subject: More story stuff - Rat, do NOT look
Date: Wed, 22 Sep 1999 16:46:14 -0700 (PDT)
Another question for another story...

Guys, how exactly do FAE (Fuel-Air Explosives) work?
Can I get an explanation in both technical and
layman's terms?

Thanks.

====Doc'
(aka Mr. Freaky Big, Super-Dynamic Troll of Tomorrow)

.sig Sauer
__________________________________________________
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Message no. 2
From: David Yiannakos yiannako@*******.edu
Subject: More story stuff - Rat, do NOT look
Date: Wed, 22 Sep 1999 19:48:15 -0400
| Guys, how exactly do FAE (Fuel-Air Explosives) work?
| Can I get an explanation in both technical and
| layman's terms?
|
| Thanks.
|
| ====| Doc'

IIRC, it permeates the air with an explosive gas, and then sets it off, but
I'm sure there's people on this list that know much more about it than
myself.

---Dave ('s not here man)
Message no. 3
From: Rand Ratinac docwagon101@*****.com
Subject: More story stuff - Rat, do NOT look
Date: Wed, 22 Sep 1999 17:39:07 -0700 (PDT)
> | Guys, how exactly do FAE (Fuel-Air Explosives)
work? Can I get an explanation in both technical and
layman's terms?
> |
> | Thanks.
> |
> | ====> | Doc'
>
> IIRC, it permeates the air with an explosive gas,
and then sets it off, but I'm sure there's people on
this list that know much more about it than myself.
>
> ---Dave ('s not here man)

Well, from what I've seen and heard it apparently uses
the fuel to ignite the air (or possibly the oxygen in
the air) itself - but that's really iffy and I need
much more concrete data than that - which is why I'm
asking.

Thanks anyway, Dave.

*Doc' points out that he did not say "spontaneously"...*

====Doc'
(aka Mr. Freaky Big, Super-Dynamic Troll of Tomorrow)

.sig Sauer
__________________________________________________
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Message no. 4
From: Xyron II markus.meisen@****.uni-muenchen.de
Subject: More story stuff - Rat, do NOT look
Date: Thu, 23 Sep 1999 03:13:54 +0200
Rand Ratinac wrote:
>
> > | Guys, how exactly do FAE (Fuel-Air Explosives)
> work? Can I get an explanation in both technical and
> layman's terms?
> > |
> > | Thanks.
> > |
> > | ====> > | Doc'
> >
> > IIRC, it permeates the air with an explosive gas,
> and then sets it off, but I'm sure there's people on
> this list that know much more about it than myself.
> >
> > ---Dave ('s not here man)
>
> Well, from what I've seen and heard it apparently uses
> the fuel to ignite the air (or possibly the oxygen in
> the air) itself - but that's really iffy and I need
> much more concrete data than that - which is why I'm
> asking.
>

<snippydip>

Well, iIrc, FAE's spread fuel (hence the "F") in very fine drops
over an area, thus creating an aerosol. So you got a really large
volume of air, mixed with fuel. This mixture is then ignited,
creating quite a big explosion.

The aftereffects are:
-Rapid contraction of the affected airmass afterwards
-Absence of almost all oxygen in the area
-(anything I might have missed above [which is probably a lot...])

Seeya,

/> Xyron II
/< (not the first, for whatever reason)
O[\\\\\\(O):::<==========================================-
\< "You always find something the last
\> place you look."
Message no. 5
From: Rand Ratinac docwagon101@*****.com
Subject: More story stuff - Rat, do NOT look
Date: Wed, 22 Sep 1999 19:44:00 -0700 (PDT)
> > > | Guys, how exactly do FAE (Fuel-Air Explosives
work? Can I get an explanation in both technical and
layman's terms?
> > >
> > > IIRC, it permeates the air with an explosive
gas, and then sets it off, but I'm sure there's people
on this list that know much more about it than myself.
> > > ---Dave ('s not here man)
> >
> > Well, from what I've seen and heard it apparently
uses the fuel to ignite the air (or possibly the
oxygen in the air) itself - but that's really iffy and
I need much more concrete data than that - which is
why I'm asking.
> <snippydip>
>
> Well, iIrc, FAE's spread fuel (hence the "F") in
very fine drops over an area, thus creating an
aerosol. So you got a really large volume of air,
mixed with fuel. This mixture is then ignited,
creating quite a big explosion.

So it's basically a hyped-up, out of control car
engine? :) Okay, more questions. Over what kind of
area is the fuel atomised? Depends on the size of the
bomb and how much fuel is in it? How big is the blast
itself? Does it exceed the area of the atomised fuel,
or is it contained to that area? Is it really the most
destructive non-nuclear explosive (I heard that
somewhere)?

> The aftereffects are:
> -Rapid contraction of the affected airmass
afterwards

Does this serve to contain the blast, or does this
only happen AFTER the blast has gone off (as opposed
to during - I know you said aftereffects, but unless
it's an absolutely instantaneous thing and it happens
everywhere all at once...)? What kind of damage (if
any) does this cause?

> -Absence of almost all oxygen in the area
> /> Xyron II

So anyone it doesn't char to a crisp will suffocate?
:) Or is that only a very short-term thing?

====Doc'
(aka Mr. Freaky Big, Super-Dynamic Troll of Tomorrow)

.sig Sauer
__________________________________________________
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Bid and sell for free at http://auctions.yahoo.com
Message no. 6
From: Iridios iridios@*****.com
Subject: More story stuff - Rat, do NOT look
Date: Wed, 22 Sep 1999 23:36:20 -0400
Rand Ratinac wrote:

> > Well, iIrc, FAE's spread fuel (hence the "F") in
> very fine drops over an area, thus creating an
> aerosol. So you got a really large volume of air,
> mixed with fuel. This mixture is then ignited,
> creating quite a big explosion.
>
> So it's basically a hyped-up, out of control car
> engine? :) Okay, more questions. Over what kind of
> area is the fuel atomised? Depends on the size of the
> bomb and how much fuel is in it? How big is the blast
> itself? Does it exceed the area of the atomised fuel,
> or is it contained to that area? Is it really the most
> destructive non-nuclear explosive (I heard that
> somewhere)?

The actual combustion is contained to the area of atomised fuel, but
the sudden ignition causes a blast wave that first blows outward past
the combustion area then blows in as air rushes in to fill the partial
vacuum created by the burning feul. The blast wave is what makes FAE
great mine field clearing devices, the same as every mine being
stepped on simultaneously.

I would say that yes it is the most destructive non-nuclear explosive,
or at least it is percieved to be. The only FAE that I know of is the
Mk-180 (IIRC) which is dropped from the back of cargo aircraft
(because it's too big to be carried by any "conventional" bomber or
fighter/bomber.

The Mk-180 (aka the Daisy Cutter), was/is used to clear dense
vegetation and/or clear and destroy airfields. That is, at least,
what I have been told.


>
> > The aftereffects are:
> > -Rapid contraction of the affected airmass
> afterwards
>
> Does this serve to contain the blast, or does this
> only happen AFTER the blast has gone off (as opposed
> to during - I know you said aftereffects, but unless
> it's an absolutely instantaneous thing and it happens
> everywhere all at once...)? What kind of damage (if
> any) does this cause?
>
> > -Absence of almost all oxygen in the area
> > /> Xyron II
>
> So anyone it doesn't char to a crisp will suffocate?
> :) Or is that only a very short-term thing?

Anybody near enough to fear suffocation, probably wouldn't get the
chance. If the actual fireball doesn't get them, the blast wave will
either a)pound their bodies into a pulp or b)blow their bodies around
so that they get pounded by the surrounding terrain.


>
> ====> Doc'
> (aka Mr. Freaky Big, Super-Dynamic Troll of Tomorrow)
>
> .sig Sauer
> __________________________________________________
> Do You Yahoo!?
> Bid and sell for free at http://auctions.yahoo.com


--
Iridios
"Accept what you cannot avoid,
Avoid what you cannot accept."
Message no. 7
From: Sommers sommers@*****.umich.edu
Subject: More story stuff - Rat, do NOT look
Date: Wed, 22 Sep 1999 23:49:53 -0400
At 07:46 PM 9/22/99 , Rand Ratinac wrote:
>Another question for another story...
>
>Guys, how exactly do FAE (Fuel-Air Explosives) work?
>Can I get an explanation in both technical and
>layman's terms?


Goto this page: http://www.nawcwpns.navy.mil/clmf/faeseq.html.
Its an animation of one exploding.

This is from a US military website:

CBU-72 Fuel/Air Explosive (FAE)

The the 550-pound CBU-72 cluster bomb contains three submunitions known as
fuel/air explosive (FAE). The submunitions weigh approximately 100 pounds
and contain 75 pounds of ethylene oxide with air-burst fusing set for 30
feet. An aerosol cloud approximately 60 feet in diameter and 8 feet thick
is created and later ignited. The main destructive force of FAE is very
high overpressure, useful against soft targets.

BLU-82 bomb: a 10,000 to 15,000 pound fuel-air-explosive. It is a near
nuclear explosive that covers an area about 1000 feet long with blast
overpressures of 200 - 1000 psi. Humans can tolerate up to 40 psi. It has
been used since the Vietnam War to blast out landing pads from the jungle.
Those near ground zero are obliterated while those on the outskirts of the
blast suffer numerous burns and internal injuries.

Generally its not a pretty thing. In the last 20 years, since Vietnam, its
only been used in the Gulf War. It was used then to clear out minefields
and similar targets.

Sommers
Insert witty quote here.
Message no. 8
From: Steve Collins einan@*********.net
Subject: More story stuff - Rat, do NOT look
Date: Thu, 23 Sep 99 00:28:29 -0400
On 9/22/99 9:13 pm, Xyron II said:

>
>
>Rand Ratinac wrote:
>>
>> > | Guys, how exactly do FAE (Fuel-Air Explosives)
>> work? Can I get an explanation in both technical and
>> layman's terms?
>> > |
>> > | Thanks.
>> > |
>> > | ====>> > | Doc'
>> >
>> > IIRC, it permeates the air with an explosive gas,
>> and then sets it off, but I'm sure there's people on
>> this list that know much more about it than myself.
>> >
>> > ---Dave ('s not here man)
>>
>> Well, from what I've seen and heard it apparently uses
>> the fuel to ignite the air (or possibly the oxygen in
>> the air) itself - but that's really iffy and I need
>> much more concrete data than that - which is why I'm
>> asking.
>>
>
><snippydip>
>
>Well, iIrc, FAE's spread fuel (hence the "F") in very fine drops
>over an area, thus creating an aerosol. So you got a really large
>volume of air, mixed with fuel. This mixture is then ignited,
>creating quite a big explosion.
>
>The aftereffects are:
>-Rapid contraction of the affected airmass afterwards
>-Absence of almost all oxygen in the area
>-(anything I might have missed above [which is probably a lot...])
>

/delurk

Ok if you take a barrel of gasolene outside and take the cover off then
throw in a lit match what happens? Maybe you start a fire but there is no
explosion, more likely the match just goes out. Why? there isn't enough
gasoline, heat and oxygen conatined at any point to cause one. Now take
ordinary flour and pour some into a bucket and shake it up, then before
all the dust settles throw in a match. Be quick to get back though unless
you want to loose your eyebrows because if you do it right it will
explode.

Things is a gasseous or aerosol state are much more explosive than the
same material in a liquid state (not including explosives that provide
their own oxidization agents). An explosion of any type is basically just
a REALLY fast fire. The problem you get into when trying to ignite a
liquid is that as the first molecules combust and create heat they tend
to push the surrounding oxygen away from the fuel source preventing more
molecules from reacting with it and damping the explosion (possibly even
extinguishing it before it gets started).

In a fuel Air Explosive this problem is solved by filling the air with a
large volume of fuel vapour then igniting the center. Now as the heatwave
expands there is still fuel there to be reacted with the oxygen creating
even more heat until ALL of the fuel is combusted gettng maximum
efficiency in the explosion.

The net result in a well constructed one is to create a tremendous shock
and heatwave very similar to the one created by a small nuclear blast,
and because nearly all of the air in the blast area has been blown out in
that shockwave a near vaccum is left behind creating another shockwave a
second or two later as the air rushes back in. If I remember correctly
the ones the US uses are in the 6 to 15 Kiloton range but are too large
to be dropped by anything smaller than a C-130. That would put them close
in destructive power to Hiroshima which was about 20Kt. The thing is that
a cheap inefficient yet effictive one can be made by anybody with a
little knowledge. You just need a gasseous or dust like fuel source, a
reasonably enclosed envrionment, and some kind of ignition device (remote
is prefered unless Suicide is acceptable). Release the fuel and wait a
few minutes for it to disburse fully then set off the ignition device.
Depending on the specifics of the situation getting an explosion the
equivilant of 1 to 2 tons of TNT shouldn't be that hard. Easily enough to
destroy just about any small to midsized building.

I'll hold off on reactivating lurk mode for a while as I will actually be
playing SR for the first time in a while soon.

Steve
Message no. 9
From: Starrngr@***.com Starrngr@***.com
Subject: More story stuff - Rat, do NOT look
Date: Wed, 22 Sep 1999 23:13:54 EDT
In a message dated 9/22/99 16:35:14 Pacific Daylight Time,
docwagon101@*****.com writes:

> Guys, how exactly do FAE (Fuel-Air Explosives) work?
> Can I get an explanation in both technical and
> layman's terms?

Sure.... Layman's explaination: Its a really nasty F@** that gets ignited.

Technical explaination: The Weapon holds a large amount of highly explosive
gas under preassure. When the weapon is triggered, first the fuel gas is
relased into the surrounding atmosphere. After a short delay (time depends
on the device) the bomb sets off a spark which ignites the gas (which by now
has diluted to burnable proportions with the oxygen in the air) and
detonation occurs. the name comes from the fact that the bonb only carries
the fuel, and uses the air in the area its dropped to ignite the fuel. For
an example of this: check out Clancy's "Hunt for Red October" (the last few
chapters) or there is also a scene in his "Red Storm Rising" where the air
force drops a couple near the key russian charecters.
Message no. 10
From: Starrngr@***.com Starrngr@***.com
Subject: More story stuff - Rat, do NOT look
Date: Thu, 23 Sep 1999 00:26:00 EDT
In a message dated 9/22/99 19:33:36 Pacific Daylight Time,
docwagon101@*****.com writes:

> Does this serve to contain the blast, or does this
> only happen AFTER the blast has gone off (as opposed
> to during - I know you said aftereffects, but unless
> it's an absolutely instantaneous thing and it happens
> everywhere all at once...)? What kind of damage (if
> any) does this cause?

I dunno if his books have made it to Oz, but in addition to the two I cited
earlier, in Dale Brown's book "Sky Masters" the lead charecter drops a FAE
for evaluation. The bomb does most of its damage due to heat and
overpressure (Ie shockwave). The bomb in question was 2600 lb model and
tossed tanks around inside of 500 ft of ground zero. It knocked down wooden
fences up to a mile from GZ. Its also of interest to note that this weapon
would be delivered in much the same manner as a nuclear device... a bombing
tactic known as a lob or toss. Otherwise the deliver vehicle would be so
close when the bomb goes off that it would be destroyed as well.

From a Physics point of veiw two things would happen. The fuel air mixture
would combust extremely rapidly. This would cause a wave of heat and
pressure from the expanding gasses of combustion (this is how all bombs work,
btw) Once the fuel had been expended, there would be an area of low pressure
left behind, and the air would flow back in to fill this vacuum. The net
result of this (IMO and depends on the force of the blast) would tend to
extinguish remaining fires, and since the air that flowed back into said
vaccum was not used in the combustion process, there would still be enough
oxygen to support life (assuming they survived the blast somehow)

And yes, I feel that describing said bomb as pond for pound the most powerful
of any short of a nuclear device is quite accurate.
Message no. 11
From: Arclight arclight@*********.de
Subject: More story stuff - Rat, do NOT look
Date: Thu, 23 Sep 1999 11:55:30 +0200
And finally, Rand Ratinac expressed himself by writing:

> -----Original Message-----
> From: shadowrn-admin@*********.org
> [mailto:shadowrn-admin@*********.org]On Behalf Of Rand Ratinac
> Sent: Thursday, September 23, 1999 1:46 AM
> To: shadowrn@*********.org
> Subject: More story stuff - Rat, do NOT look
>
>
> Another question for another story...
>
> Guys, how exactly do FAE (Fuel-Air Explosives) work?
> Can I get an explanation in both technical and
> layman's terms?

There was a thread about this some time
(about 2 month) ago. As there were a lot more
things discussed than just how it goes bang,
you might search the archive for the posts.
Topic was "Fuel-Air Bombs", among others. If
you cannot find them, ask me privately

arclight
Message no. 12
From: Sebastian Wiers m0ng005e@*********.com
Subject: More story stuff - Rat, do NOT look
Date: Fri, 24 Sep 1999 08:43:11 -0500
> > | Guys, how exactly do FAE (Fuel-Air Explosives)
> work? Can I get an explanation in both technical and
> layman's terms?
> > |
> > | Thanks.
> > |
> > | ====> > | Doc'
> >
> > IIRC, it permeates the air with an explosive gas,
> and then sets it off, but I'm sure there's people on
> this list that know much more about it than myself.
> >
> > ---Dave ('s not here man)
>
> Well, from what I've seen and heard it apparently uses
> the fuel to ignite the air (or possibly the oxygen in
> the air) itself - but that's really iffy and I need
> much more concrete data than that - which is why I'm
> asking.
>
> Thanks anyway, Dave.
>
> *Doc' points out that he did not say "spontaneously"...*

No, Daves right. The basic point is to liberate all the fuels energy
(which is a LOT- fuel is, by definition, energy dense) at once (which is
sometimes hard to do- fuels are fairly stable, which is why they are not
explosives). There was a HUGE thread about this a while back, but maybe
that was on rec.games.frp.cyber.
To this end, FAE's genrally use a charge to quickly distribute (and
atomize, in the case of liquids) the fuel, mixing it with atmospheric oxygen
and possibly oxidizers from the bomb itself. Microseconds later (this
timing being the tricky part), another charge evenly ignites the whole
cloud. In short, what happens in a cars engine is made to happen in the
atmosphere on a large scale (at least, that's the goal).
FAE's are nice because the damage is widely distributed and even
throughout the area of effect. They are potentially more powerful than
normal explosives of the same mass (because they use outside oxygen to
detonate, as opposed to fueling their own explosion). They can be made from
cheap materials and even improvised (open up a propane tank and let it mix
into a volume of air, then ignite, or add fuel around a normal explosion),
but to have maximum effect (the "baby nuke effect"), they need some heavy
duty engineering and special chemicals. On the other hand, a propane
explosion is nothing to sneeze at...

Mongoose

P.S. Oxygen does not burn, and cannot be ignited. It is, by definition,
and
oxidizer, and its presence in large amounts makes other things burn somewhat
more easily. It is NOT explosive, nor is pumping a bunch of oxygen into a
room liable to cause an explosion. That's why fuel gasses are scented
unpleasantly (to prevent explosions from accidental release of gas); oxygen
not intended for breathing use is not so scented.
Message no. 13
From: Aaron saarons@*****.colostate.edu
Subject: More story stuff - Rat, do NOT look
Date: Fri, 24 Sep 1999 07:45:24 -0600
>Mongoose
>
>P.S. Oxygen does not burn, and cannot be ignited. It is, by definition,
>and
>oxidizer, and its presence in large amounts makes other things burn somewhat
>more easily. It is NOT explosive, nor is pumping a bunch of oxygen into a
>room liable to cause an explosion.

"Large amounts" = O2 levels are raised to make it about 25% of the
atmosphere, then the conditions become *much* more explosive.




S. Aaron Spriggs, Bugologist
Entomologists know how to spread 'em and pin 'em.
Message no. 14
From: David Yiannakos yiannako@*******.edu
Subject: More story stuff - Rat, do NOT look
Date: Fri, 24 Sep 1999 12:13:17 -0400
| "Large amounts" = O2 levels are raised to make it about 25% of the
| atmosphere, then the conditions become *much* more explosive.
|
|

Very true. Ask the elderly lady here in Rochester a couple of months ago who
had been on oxygen for twelve years, living in the same house and one day
decided she wanted a cigarette....

*Very Bad Things*

---Dave ('s not here man)

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