"Pooh Bear" wrote in message
...
Ralph Nesbitt wrote:

"Scott M. Kozel" wrote in message
...
"Ralph Nesbitt" wrote:

"Duster" wrote

Holy **** and all I wanted was a video... hehe this is almost
better
though..

Tarver cannot get it through his head that having the air handling
units
operating under the CWT when the A/C is stationary is like putting a
pressure cooker with a small amount of fuel in it, on a stove at low
heat.

There have been several incidents world wide where Boeing A/C of
various
models have exploded sitting at gates, on ramps, taxing out, or
shortly
after take off after sitting with the air handling units running
under ~
empty CWT's.

There are now "Air Safety Directives" stipulating/requiring certain
operating protocols to minimize this hazard associated with the
"Boeing
CWT
Design Philosophy".

Splaps Boy is correct in that the A/C is not a "bomb" in the
conventional sense of large object full of high explosive that is
gravity-dropped on a target, but a Boeing 7x7 aircraft's CWT with the
right fuel-air mixture if detonated can equal several sticks of
dynamite
in explosive power.

Please note "Splaps Boy" is the one screaming "Bomb" not be. I am simply
pointing out "The Boeing CWT Design Philosophy" results in conditions in
the
CWT of Boeing A/C conducive to "Self Initiating FAE's (Fuel Air
Explosion)".

Self - initiating ? I've never known a fuel air mixture explode of its own
accord outside a diesel engine. Especially with quite low temps.

An ignition source is also required.


Certain specified operating protocols have become minimum SOP to limit
the
"Inherent Danger" associated with"The Boeing CWT Design Philosophy".

As in turning off the fuel pumps with the dodgy wiring when the tank is
low ?


Graham

For details regarding the "Self-initiateing" comment above see:
http://www.galcit.caltech.edu/EDL/pr...nceptions.html

There are references to several scientific papers here. Effectively it is
not uncommon for the "Air Temp" inside the "Vapour Space" of an A/C with a
"~ empty CWT" sitting on a ramp in high ambient temp conditions with the air
handling units running, to exceed the "Flash Point" of "Jet A Vapors" within
the ambient atmospheric conditions.

The upper & lower flammable limits of Jet A vapors vary with atmospheric
pressure & temp of the vapor. When Jet A Vapor that has been heated to a
Temp close to it's self ignition Temp at a given atmospheric pressure, a
change in the atmospheric pressure can result in self ignition resulting in
an FAE.
Ralph Nesbitt
Professional FD/CFR/ARFF Type