[sci.military] Reactive armor

jonke@BRL.MIL (Patrick Jonke) (02/04/91)

From:     Patrick Jonke <jonke@BRL.MIL>
(Note: This is my first submission to sci.military so please forgive me
if I do something incorrectly!



> From:     "Larry W. Jewell" <JEWELLLW@VM.CC.PURDUE.EDU>

> Footage from Sandy Arabia shown M-60's with large flat plates attached
> to the turret.  Is this reactive armour?

Yes.

> Any idea how it works and how much confidence the tankers have in it? 

First generation reactive armor consists of two thin metal plates sandwiched
around a slab of explosive.  When a shaped-charge jet penetrates the outer
plate, it detonates the explosive filler which then propels the outer metal
plate away from the vehicle and the inner metal plate towards the vehicle.
Because the plates are (hopefully) at an angle to the jet, new metal is
continuously placed in the path of the jet.  Here is a crude diagram to show
how this works:

						    		 __
                                                   /            |\
                                /                 +               \
              /                +                 +                 \
JET t=0 ----->      JET t+1 --+-->     JET t+2 -+--->           Direction of
            /                /                 /                 plate motion
           /                /
          /

The greater the angle of incidence, the more metal that is placed in the path
of the jet.  If the jet strikes perpendicular to the plate, the reactive
armor provides negligible additional resistance.

brims@bnkl01.astro.ucla.edu (06/14/91)

From: brims@bnkl01.astro.ucla.edu


A lot of postings on tank technology mention reactive armor. What
nobody mentions is what it's like for the crew of a tank when an
incoming projectile is rejected by reactive armor. How loud does it get
in there? I imagine it must be pretty bad (yes I know it's infinitely
preferable to what happens if the shell penetrates :^) ). Is the crew
even functional after the concussion? Any figures on how likely a tank
is to survive after one unsuccessful hit? Any personal experiences?

George Brims
UCLA Astronomy Department
brims@bnkl01.astro.ucla.edu

bxr307@coombs.anu.edu.au (Brian Ross) (06/16/91)

From: bxr307@coombs.anu.edu.au (Brian Ross)


brims@bnkl01.astro.ucla.edu writes:
>A lot of postings on tank technology mention reactive armor. What
>nobody mentions is what it's like for the crew of a tank when an
>incoming projectile is rejected by reactive armor.

What is even more lightly passed over is the effects on your own
accompanying infantry.  You think what it would be like if your
standing near a tank which has ERA and it gets hit by an anti-tank
missile.  You not only have to contend with the fragments flying around
from the missile, but also from the ERA boxes which have exploded.
Even worse for the tankers is what happens to all that extra gear they
have stowed on the outside of the vehicle? ;-)

	[Still seems like a good deal for the tankers, considering
	 the alternative... 
	 But can anyone comment on Military Tactics for Infantry
	 accompanying tanks with Reactive Armor?  Do they change anything?
	 --CDR]

--
Brian Ross

amoss@cs.huji.ac.il (Amos Shapira) (06/19/91)

From: Amos Shapira <amoss@cs.huji.ac.il>
Brian Ross writes:
|A lot of postings on tank technology mention reactive armor. What
|nobody mentions is what it's like for the crew of a tank when an
|incoming projectile is rejected by reactive armor.

This issue has allready been addressed in this group a few months ago. The
consensus was that the crew almost doesn't know that the tank was hit and
that even firing the tank's own gun gives much more impact than a hit by a
shaped charge with a reactive armour.

Cheers,               | "We took of, flew, bombed, returned, landed".
Amos Shapira          |        The summery of the commander of the Israeli
amoss@cs.huji.ac.il   |        raid on the Osirak reactor in '82

patter@bellcore.bellcore.com (06/25/91)

From: mruxb!patter@bellcore.bellcore.com
Try a book called "Brazen Chariots". I think it's in the Bantam war series.
The author commanded Stuarts in North Africa. I don't recall the details,
but his tank was hit at close range by a German PAK gun. As I recall, the
water and gas cans on the back saved his but and he promptly departed the
scene - with some new air conditioning!