Your observation about stealth having potential cost advantages is right on. If you're stealthy EMCON is the way to go. A big cost saving if you use composites, you need a much smaller deck force to chip and paint :) I envision something that looks like the Confederate Merrimac. All those perpendicular surfaces on ships make great targets. A carrier is not bad, but an LHD/LHA is a big butt target. Fortunately I don't count them as front line. They go in after the stealth ships and aircraft have taken control. (goes back to my submarine rail gun)

The long range 5 inch gun is probably a bust. It is the reason someone said RAP is expensive. It isn't. But OUR fancy one is: they want to use the RAP as a guided missile - a smart shell that can even shoot down air targets! They cost over 60000 dollars, and still don't work right. This is not my meaning for RAP. If one uses base bleed, special shell shapes, and simple RAP, one can get ranges of interest - 39 to 52 km in the case of NON RAP shells - 50% more with it.

Hi, Can you suggest any sites that might bring me up to speed on things like base bleed etc? Al

The reason ERGM (the fancy 5-inch RAP shell you refer to) uses guidance, and is therefore expensive is that at 62nm there is simply no other way to get it within a useful distance of the intended target. ERGM is BTW, does not have an AAW capability as you claim. I'm curious about something. How does one use both RAP and base-bleed on the same projectile. You imply this is possible. How so?

Actually, couldn't we use a predator or a globalhawk to feedback to the gunners what corrections to make? This eliminates all need for any guidance. And on a cloudy day we shoot a GPS round every so often that tells the gunners where they are hitting.

How does that eliminate the need for guidance? All ballistic projectiles suffer from dispersion. It doesn't matter if the target is covered in flashing lights with a bullseye painted on it. At 63nm a ballistic projectile is going to have a CEP measured in kilometers. That's just physics. To illustrate what I'm talking about see the follwing link. Pay special attention to pages 10-13. http://www.dtic.mil/ndia/2002artillery/ocain.pdf

Sadly everytime I try to download that file, it seems to freeze my computer after 30+ minutes of loading. FWIW - I suspect the long range rounds will have some kind of simple GPS system.

It's a big PDF file, and if you don't have high-speed your probably out of luck. Curiously though, as I write this I can't get it to open either, while it opened right away the other day. Nor could I get another PDF from the same site to load. They may be having problems.

In the absence of being able to read that file, could you provide some insight? What factor is most significant in determining CEP? Is it the gun itself or the factors after it leaves the muzzle?

Dispersion is natural and lots of things are responsible for it. Projectiles never go "strait-and-true" for very long once leaving the muzzle. Weather, barrel wear, minor variations in velocity and so on affect overall accuracy. The PDF document (which is working now but slower to load than it used to be) indicates as an example that at 15 NM range typical dispersion for unguided artillery projectiles will account for a CEP of 320 meters. The CEP represents a circle in which one-half of the projectiles fired are expected to fall within. So draw a circle 320 meters in diameter and think about half the rounds you shoot landing inside of it, the other half outside of it. At 20 NM that CEP increases to 428 m. At 25 NM it increases to 535 m. At 35NM the CEP is a whopping 750 m! That means some projectiles are landing as far away as 1,800 m from the target! When you have a projectile with a lethal radius of say somewhere between 50-100 meters you can see how landing almost 2 km from the intended target can be a problem. It creates collateral damage, requires a lot more rounds fired for a given effect on target and increases the "danger-space" distance between the target and friendly forces. On another slide the effect of dispersion is shown on an aerial photograph of a nieghborhood, with dots overlayed on the photo to represent where each projectile might hit. At 10 km range it would take on average 68 unguided artillery shells to achieve 1 hit on a target building (like a house), with many of the misses landing blocks away. With a guided projectile (ERGM in the example) 6 rounds fired would achieve multiple hits with all rounds landing within lethal radius of the target - very little collateral damage, very small danger-space. Why? Because by adding guidance, in this case INS (Inertial Navigation System) backed up by GPS the CEP can be reduced at all ranges to between 10-20 meters, not 750! BTW Guided artillery rounds incorporating GPS such as ERGM and Excalibur are almost invariably referred to as "GPS-Guided". This isn't true. They rely on INS for navigation. GPS is there to provide position updates at various points in the flight. On INS alone (no GPS signal) considerable accuracy is retained.