"Gunner Asch" wrote in message
...
On Wed, 21 Dec 2005 04:28:30 GMT, Shmaryahu b. Chanoch
wrote:

Shades of Star Trek IV, "The Voyage Home", and the transparent aluminum
used to
create an aquarium for the whales on board the spaceship. Now it really
exists
and is coming into use for bulletproof vehicle windows. (Great for
embassies or
even aircraft).


Geostrategy-Direct
Week of December 20, 2005
MILITARY TECHNOLOGY

U.S. tests new ceramic armor made of aluminum oxynitride

The U.S. Air Force has tested a transparent armor that is stronger and
lighter than traditional materials and is capable of stopping
armor-piercing
weapons from penetrating vehicle windows. The armor is meant to replace
traditional multi-layered glass transparencies - thick layers of bonded
glass - installed in ground and air armored vehicles.

The Air Force Research Laboratory's materials and manufacturing
directorate
evaluated aluminum oxynitride, or ALON - a ceramic compound having high
compressive strength and durability.

First Lt. Joseph La Monica, an Air Force officer involved in the project,
said that ALON represents the premier transparent armor for use in combat
vehicles. La Monica said ALON is "light years ahead of glass" and offers
higher performance and lighter weight.

ALON is virtually scratch resistant, ensures substantial impact resistance
and offers better durability and protection against armor-piercing
threats.
The substance, which can also protect helicopters, is about half the
weight
and thickness of traditional glass transparent armor.

The new armor employs a transparent piece of ALON as a strike plate with a
middle section of glass and polymer backing. Each layer is visibly thinner
than traditional layers.

In a June 2004 demonstration, ALON withstood both a .30-caliber Russian
M-44
sniper rifle and a .50-caliber Browning sniper rifle with armor piercing
bullets. While the bullets pierced the glass samples, the armor withstood
the impact without penetration.


ALON was also tested against multiple hits from .50-caliber rounds. The
tests also sought to determine whether the substance could withstand
improvised explosive devices.


It would be nice if there was some info. on ALON thickness. Just to say it
can resist penetration from a .50 armour piercing loses meaning. Lexan at
some thickness can do the same. In fact ANY material at some thickness would
stop the .50 cal.
I agree it must be quite the material though. Just for reference, does
anyone know how thick a plate of mild steel would need to be to stop a .50
cal AP?

Dixon