This reply is dedicated to Numbers.
http://asymmetronix.livejournal.com/608.htmlPossible advantages of an auto-loading & -homing AAA-gun with guided shells and with a muzzle velocity of 1km/s (mach 3) over an AA missile with an acceleration of say 50g (max. ever was 100g !):
1) cheaper
2) "reload" time and mass storage
3) excluding drag (missile has much larger diameter), missile would overtake shell at not less than 4km.
Disadvantages:
1) IR sensor matrix just too expensive when crude guidance is factored in!
2) 100mm maybe too small for built-in guidance, 155mm (the Ground artillery standard!) too expensive
Auto-homing could be accomplished by extending either the spin stabilization (SS) technology -modified Base Bleed (moBB); or BB combined with foldout vanes on a slip ring (srBB)- or Smooth Bore foldout vanes (SB) technology. The latter would be less complex but would limit this type of artillery to SB shells only, apart from the fact that the vanes would need to be folded out as soon as the shell leaves the barrel (instead of in the terminal homing phase only), increasing air friction considerably.
At 4km range a competing 50g missile would have a velocity of approx. mach 7 (> 2000m/s) making it one of a select elite of state-of-the-art AA-missiles (S-300 e.g.)!
Summarizing, two or more of these "guided" shell AAA-guns (medium-range) with a Goalkeeper (short-range) would be a great point defense system against any ordnance with a substantial IR signature (dumb and smart bombs, AGM's, cruise- and possibly ballistic-missiles) with these advantages:
1) cheap
2) faster (automated) reload
3) more ordnance per storage unit
4) small RCS
5) no missile exhaust trail
The conjectures in the quote were inspired by a YouTube video of the AAA system mentioned in this thread, in which the shell seemed to autonomously change its trajectory towards the target. This video has been widely debated on military forums up till about a year ago when it was removed unfortunately.
Note:
The thing with Point Defense Systems is, they don't have to be camouflaged or to "scoot after shooting" unless you want to mask the importance of the site. So a
155mm multipurpose (Anti-Air
and Anti-Ground) gun with a long enough range, could remain stationary and still be used to engage ground targets as well, in coordination with other guns within its range. Another advantage could be that 155mm AA and AG shells are large enough to hold
sub-munitions.