Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!sdd.hp.com!zaphod.mps.ohio-state.edu!pacific.mps.ohio-state.edu!linac!att!cbnews!cbnews!military
From: thos@softway.sw.oz.au (Thomas Cohen)
Newsgroups: sci.military
Subject: Re: loose threads
Summary: Base bleed Vs Rocket assist
Message-ID: <1991Feb9.025436.29635@cbnews.att.com>
Date: 9 Feb 91 02:54:36 GMT
References: <1991Feb7.013344.1181@cbnews.att.com>
Sender: military@cbnews.att.com (William B. Thacker)
Organization: Softway Pty Ltd, Sydney, Australia
Lines: 40
Approved: military@att.att.com



From: thos@softway.sw.oz.au (Thomas Cohen)
In article <1991Feb7.013344.1181@cbnews.att.com> wilkinson@PICA.ARMY.MIL (CCL-C) writes:
>
>On another subject, someone posted the "fact" that Iraq has
>base-bleed artillery projectiles and can therefore out-range
>our guns.
>Well........base bleed is basically just a much cheaper way
>of achieving the same results as rocket assist. And since we

Not at all!  Base bleed simply cancels out the base drag by
burning a low grade propellant and allowing the gas to occupy
the area of low pressure behind the shell's blunt end. This
area of low pressure causes drag (and probably turbulence).
So the projectile is aerodynamically shaped at both ends, but
no extra propulsion has been added.

Rocket propelled/assisted shells have more propulsion than
the normal shell, and a greatly longer range. They also have
a greatly reduced accuracy, even if (as is usual) the rockets
give some form of spin to the shell.
The accuracy of base bleed shells is not diminished, in fact
if anything, it's probably increased from the loss of drag and
(probably) turbulence. Of course, since the shell is travelling
further, it is more likely to be affected by wind etc over its
trajectory.

>Iraq has nothing even approaching this.

But do you/we have any divisional arty which can shoot to the
ranges of the South African designed 155mm? (~45km, or thereabouts)
Wasn't Dr G Bull involved with the development of these field
pieces? And is the phenomenal range (for the calibre) due to 
the propellant, the charge, the projectile or the gun?
-- 
thos cohen  				       |Softway Pty Ltd
"Stopping to pick up passengers would disrupt  |ACSnet:         thos@softway.oz
 the timetable"    - Alderman Cholerton, on why|UUCP: ...!uunet!softway.oz!thos
 the council's buses didn't stop for passengers|Internet:    thos@softway.oz.au