We previously discussed the general need for and benefits of armor. Now, let’s look a bit closer at the specific case of armoring weapons. The WWII ship designers recognized that it was pointless to build a ship whose main weapons could be easily disabled. Gun mounts, the main weapons of the day, typically had twice or more the armor protection of the rest of the ship. For example, the Fletcher’s 5” guns were protected by 1”-2” of armor while the rest of the ship had ½”- ¾”. Compare that to a modern destroyer whose 5” gun has absolutely no armor, just a thin weather covering. How long will a Burke’s 5” gun survive in combat? Yeah, not long.
|WWII 5"/38 Gun - The Last Part To Fail|
I know some of you are leaping for your keyboards, already furiously typing out a snarky reply pointing out that the 5” gun of a modern destroyer is not its main weapon. Well, hit the backspace key, relax, and keep reading. What is the main offensive weapon of a Burke DDG? For anti-ship work, it would be the Harpoon missile. The Harpoons are housed in totally unprotected quad launch racks out in the open on deck. Simple shrapnel can destroy them. For land attack, the Tomahawk is the main weapon and those are housed in VLS cells which I think have some degree of armor protection but I’ve been unable to determine how much protection they have. Further, the protection that the cells have seems to be designed to protect the rest of the ship from an explosion of the stored missiles rather than to protect the missiles, themselves, from incoming weapons. Thus, the bottom and sides of the VLS pit seem to be protected but the exposed deck face appears to have little protection.
What about the Burke’s main role of AAW? Well, the Standard missiles, like the Tomahawks, are housed in the VLS so, again, they may have a small degree of protection. However, the Standard missiles are only usable if they can be guided to their target. What provides the guidance? Three completely unarmored and unprotected SPG-62 illuminators with two of them clustered within about ten feet of each other on the aft superstructure.
So, we see that the guns and Harpoons are completely unprotected while the VLS missiles are protected to an unknown degree although the illuminators are vulnerable. Little can be done to protect the illuminators without impacting their performance although greater separation would be nice so that a single hit can’t take out multiple illuminators.
It is also technically possible to house the illuminators in armored recesses on retractable mounts. The illuminators could be exposed when needed and retracted if hits were imminent – for example, when incoming missiles reach the ESSM and SeaRAM range, the illuminators are no longer necessary. The Soviets and others have used retractable missile launchers so the concept is perfectly feasible.
This is also another reason for making extensive use of SeaRAM and Phalanx CIWS with their self-contained radars. A hit on any one unit does not disable the functionality of all the others.
While sensors and illuminators are somewhat challenging to protect, the guns and Harpoons could be easily protected. Armored mounts for the guns would be a simple and cost effective way of enhancing their survivability. As we’ve previously discussed, an inch or two of mount armor won’t protect against a direct hit from a cruise missile but it will ensure that a mount can’t be destroyed by simple shrapnel. Harpoon missiles can be placed in recessed “pits” with armored walls – not perfect but better than the current situation and analogous to the VLS protection. This would also somewhat enhance the stealth signature. Such weapon pits have been used on various ships such as the Egyptian Ambassador missile boats and the Absalon class although the degree of armoring of the side walls, if any, is unknown.
|Ambassador Mk III With Recessed Weapons Pit|
To be fair, the Harpoon is all but obsolete and any further effort at armoring is probably not worth the cost assuming the VLS-capable LRASM is deployed in the next few years. Also, the more recent Harpoon canisters are thicker walled to, presumably, provide a small measure of shrapnel protection although the degree of protection is questionable.
The overall conclusion is that the Navy no longer designs ships for sustained combat. Today’s design philosophy seems to view ships as short-lived, offensive launchers with no sustained combat capability in the face of damage. Indeed, the LCS is intentionally designed to be abandoned at the first significant hit! Recent grounding, explosion, and collision experience suggests that the Ticos and Burkes are extremely sensitive to even mild damage and will become one-hit mission kills in combat.
We need to return to the WWII design concepts where the main weapons are the last part of a ship to fail in combat. We need to design in a much greater degree of protection for our weapons and critical sensors than we currently have and there is no technical reason why we can’t. It just requires a combat mindset from the outset. The required changes and protections are not particularly difficult and require only the admission that our ships will take hits in combat and the determination that we should be able to keep fighting after taking hits.
Our ships have, for too long, been designed for peacetime operations instead of war. This must change.
The common twin 5” gun mount of WWII had protective mount shields that varied from ¼” thick to 2.5” thick, depending on the shield version and the specific location on the shield. The Mk28 shield, for example, was a uniform 2.0” thick. (1)