Tracked or Wheeled

[angevin@juno.com (Joseph P Benedetto)]

>I have a couple of questions about this:  For MARS combat units would
>tracked vehicles be useful?  How much of an improved cross country 
>ability do you get for a tracked vehicle as opposed to a 4-6 or 8
>wheeled combat vehicle?

Tracked vehicles as a rule put down less weight per square foot in their
"footprint" then wheeled vehicles do.  This is one reason why tracklayers
can move across broken or unstable (soft, muddy, etc) terrain that would
bog down a wheeled vehicle.

Conversely, it IS possible to mount larger weapons on wheeled vehicles;
you just can't get the same armor protection due to weight
considerations.  Still, many armored cars today can mount the 90mm
cannon, which gives them firepower close to that of main battle tanks. 
(But they just don't have the same survivability--remember, a lot less
armor is riding above those wheels!)

Most armored cars have less cross-country capability than a tracklaying
vehicle, which is one reason to use tracks: better off-road capability. 
HOWEVER, the Brits got around this with their excellent 6-wheeled Alvis
FV 600 line of vehicles (an APC, an 76mm armored car and a cargo carrier
all built on the same chassis).  The Fv 600 6x6 series had a
cross-country capability close to a tank, and saw service in numerous
British countries (some of which are still using it!). The 76mm gun,
which dates back to the late 1950's, has been upgraded using a HESH
shell, which gives it a credible tank-killing capability.  You don't need
a tracklayer, save if you want a rolling pillbox.

And the argument for wire-guided AT missiles like the TOW series are also
very valid, and these weapons DON'T require a large chassis to mount
them.  The M113 has not much more armor than a MP armored car, yet it can
carry the twin TOW launching pod and has an excellent tank-killing
capability.  Of course, it can't slug it out with a tank--it's designed
to ambush one, hopefully from several kilometers, and let it have it
before it knows it is in trouble!  So the TOW missile is a very viable
option to the 90mm gun on an MPV, and it IS possible to develop a wheeled
vehicle capable of excellent cross-country handling.
 
Joe
angevin@juno.com