Re: [DS2] Yet more firing arcs

----- Original Message -----
From: Bell, Brian K <Brian_Bell@dscc.dla.mil>
To: Gzg-L (E-mail) <gzg-l@CSUA.Berkeley.EDU>
Sent: Tuesday, March 21, 2000 12:07 PM
Subject: [DS2] Yet more firing arcs

> Greetings!

> In preperation for my planned game in GZG-ECC IV, I ran
> into a situation that the rules do not cover (or at
> least I was unable to find the appropriate rules).
>
> The area that the battle will take place in has some
> rather steep hills. As such, AFVs may end up on the
> side of a hill at the end of movement. This, obviously
> exposes thier top armor. But the question is -- What
> can they target?
>
> What is the maximum elevation for today's AFV main
> weapons (not including artillery or Anti-Air)? I do not
> have access to a reference such as Jane's at the
> moment. My guess would be that it would not extend to
> 45 degrees. If someone knows the real figures, it would
> be appreciated (may send to me off-list to avoid clutter).

This is probably on-topics enough to warrant a reply on list (it's as
on-topic as some other recent discussions ;-))

I can't find our company copy of Jane's AFVs, but I can remember from my
Modern micro-armour days that MBTs have fairly pitiful elevations /
depressions - in the order of +15º / -8º. Russian MBTs are even worse,
something like +10º / -4º. The main problem is the amount of breech
that
projects into the turret. On very low profile AFVs such the the T-55 /
T-62
/ T-72 there's almost no clearance for the gun to depress.

> And what is the best way to easily apply this to the game?
> I had thought about getting a small disk of styrofoam and
> cut a cone into the top at the appropriate angle for a
> visual aid.

Again harking back to my micro-armour days, I seem to remember that
vehicles
on hills would be considered to be horizontal. They then had a 'dead
zone'
in front of them into which they couldn't fire. Just doing a quick bit
of
maths, a vehicle on level ground 100m above the plain below (ie the
table)
would not be able to hit a target within 711m (8º depression) or 1430m
(4º
depression). This was intended for tables on which the terrain was
represented by stepped hills, so each hill level represented 25 or 50m
(can't remember exactly). This meant that you had to apply some major
thought to vehicle placement - a Russian tank company on a 4 level hill
couldn't hit any target within 1400m, or 28" using 1"=50m ground scale.

I don't think that attempting to physically measure angles will work -
we're
talking about very small angles, and a small piece of flock under the
rear
of your tank at this scale could make all the difference between being
able
to hit the target and not. Better to apply some abstract method (such as
outlined above) IMHO.

> What would be fair numbers for elevation/depression of
> AFV main armorment?
>
> Perhaps size would come into play in these calculations?
> Class 1s have 90 deg elevation
> Class 2s have 60 deg elevation
> Class 3+ have 30 deg elevation

If I can find our copy of Janes I'll look up some real numbers. However,
the
above are way too high for real-life MBTs. Actual elevation values
depends
on the use of the vehicle (IFVs sometimes have high elevations so that
they
can hit the upper floors of buildings in urban fighting), the size of
the
main armament (ie is there room to elevate / depress the gun inside the
turret) and the build of the vehicle (you could use the vehicle's
stealth
factor - higher stealth = lower profile = less room to elevate the gun).

Tony