The 5/54 would outrange tank cannon, but only when you reach 17-18km and at that point existing 5in caliber ammunition from a single gun barrel would just not be effective against moving tanks. Tomahawk missiles are not suitable for attacking moving tanks ashore. Vague chances would exist to score hits, but the destroyer isn't equipped with the systems needed to make that useful. They would have value against artillery pieces, if said could be located, which is iffy since SPY-1 radar isn't designed for counter battery missions and has very limited if any ability to do so against cannon type weapons, locating rockets and missile launches is much easier as they have much larger radar signatures. A 155mm shell is almost a stealth target just from being small, missiles, as well as mortar rounds, have big fins which make them way easier to detect with an S-band radar.stardust wrote:What Jub said. Good to know.
I was more thinking if they could spot tank columns alongside a riverbank, that their missiles and gun system would outrange any tank based weapon. But feel free to prove me wrong!
The X-band SPY-3 does have a dedicated counter battery mode but that's only on the Ford class aircraft carrier, and to be but not yet fitted to the DDG-1000 hulls which are not yet operational. It may never see service on anything else as the USN is now designing a much more advanced radar for future Flight III DDG-51s in the mid 2020s with largely classified capabilities and design goals.
Now meanwhile the odds of the destroyer detecting a concealed tank on the shore are pretty damn low, a bit ironically the best USN optical fire control systems are actually on the ESSM illuminators for aircraft carriers and amphibious ships, and if the tank was not detected before it fired then unless the range is over 5,000m it would stand a high chance of scoring a first round hit on or near a specific vital spot on the destroyer, like the CIC or the Mk41 silos, or the 5in handling room, all of which are above the water line.
Seriously back in the cold war the USN assumed its 5in 54cal gun armed destroyers would loose to the Soviets 130mm S4 mobile coastal gun (a towed weapon no less) and modern mobile artillery pieces are far more capable. The original solution to that was a naval 175mm gun, as all the old cruisers and battleships were leaving the fleet, which morphed (due to army abandoning 175mm) into the 8in Mk71. But that things thunder was stolen by the short lived reactivation of the Iowa class... and after the Iowa class went away the present efforts for extended range guided ammo and the 155mm AGS began...and have all faltered in turn largely due to unrealistic and shifting requirements. Plus the lack of pressing need and the enormous leaps taken by guided artillery missiles like GMLRS, which work both ways too, anyone who can build a computer can build something like GMLRS. It might not work as well or be as cheap or reliable, but if just enough of them work that doesn't matter.
