Sunday, May 11, 2014

The US Navy's escorts - where do we go from here?

Lazarus, one of the contributors at Information Dissemination (which is a must-read for naval and military pundits and ponderers), brings us an excellent overview of US naval escort design since World War II, and its implications for the fleet's current operational doctrine.  Here's a brief excerpt.

U.S. surface warships of all sizes from the 15,000 ton Zumwalt class destroyer to the 3000 ton Littoral Combatant ship are all descendents of the frigates (DLG) built just after the end of the Second World War. A combination of a new operational concept, new threats at sea, and rapidly advancing technology combined to create a persistent design in U.S. surface combatants that endures to the present day. The postwar surface combatant has been primarily assigned as a defensive platform based on the experience of World War 2 and those that followed in Vietnam. Its design features the primacy of sensory, communication and weapons control equipment over stout construction and armor. It was specifically designed to support defensive rather than offensive missions. These features have been a constant in a parade of ships that have entered the fleet from 1947 to 2014. If senior national security decision makers desire greater lethality and enhanced survivability in future surface combatants, the characteristics so prevalent in U.S. warship design since the late 1940’s must be re-evaluated.

There's more at the link.

I agree with many of his points.  For example, I want to see much more heavily armed smaller vessels than the current Littoral Combat Ship, which I think is woefully undergunned for its size (not to mention under-missiled and under-torpedoed).  It reminds me of the Royal Navy's then-new Battle class destroyers towards the end of World War II, of which the late Admiral Of The Fleet A. B. Cunningham complained that they were "too large" (at well over 3,000 tons) for their intended role in the Fleet and "had every damned weapon and gadget except guns".  (They had most of the electronics developed during World War II, but main armament of only four 4.5" cannon in two twin turrets.  They were much larger than - in some cases more than twice the displacement of - earlier classes of Royal Navy destroyers, most of which had been more heavily armed but with less electronics.)

Battle class destroyer HMS Lagos

For that matter, I think even the very successful Oliver Hazard Perry class frigates of the 1970's (at a little over 4,000 tons) could have done with more and better armament.

USS Oliver Hazard Perry

I like the Israeli approach, which crams lots of hitting power into even small hulls (see, for example, its Sa'ar 5 class corvettes, which as far as I know are the most heavily armed ships of their size [just over 1,000 tons] anywhere in the world, and on an armament-per-ton or tons-per-weapon basis might be the most heavily armed warships since the age of the dreadnought).

Sa'ar 5 class corvette INS Eilat

The article makes interesting and informative reading.  Recommended.



Angus McThag said...

It just hit me...

Zumwalt displaces more than CV-7 Wasp!


Sherm said...

I'm currently reading a joint biography of Admirals Nimitz, Halsey, Leahy, and King and how they ended up where they were for WWII. When I look up information about ships they commanded the specifications always talk about the belts armor protection. It's never mentioned on current ships. Even the CV7 Wasp mentioned earlier had three inches of armor around the conning tower. Maybe they're hoping no one shoots back.

scipioamericanus said...

You have to be really careful with just counting guns. In reality, the ship with many fewer weapons (Perry class, for instance) can prove the vastly superior warship. The difference comes down to all the things you can't see that get the guns to where they do their job, tell them what to shoot, and protect them while they shoot it. Sensors, systems, damage control, propulsion, etc.

It's a commonplace in the maritime defense analysis community that good modern warships often look undergunned. Unfortunately, then some company builds an export-market ship festooned with weapons and the government goes gaga for it, saying "why can't we make ships as fearsome as that!?" They do this in ignorance of the fact that the ship has a 3rd rate sensor suite, no redundant systems or extra crew for damage control, burns like touchpaper, and maneuvers like a garbage scow on the East River.

All of these compromises allow the weight, volume, and crew savings that are used for those fearsome turrets and missile batteries. In a real fight that ship would be reduced to a flaming wreck in minutes, hit by half a dozen enemy air and naval units it never even detected.

As I mentioned, most such ships are built for the export market, to be sold to those who don't know any better. Others are just a case of lack of naval engineering tradition or a government overruling its navy because they're overawed by all the shooty bits in the PR photos. the Israelis are actually famous for building ships like this, IIRC.

Rolf said...

Scipio - I think what many would contend is that guns and sensors are not mutually exclusive. Having multiple independent gun systems, missile systems, torpedo systems, sensor systems, etc., seem like common sense to me. The weight savings in going from five to two CWIS mounts, for example, is trivial. The logistics overhead for mounting two twin-turret 5" guns vs one single gun mount is relatively trivial, but it greatly increases redundancy and offensive capacity. A couple of lucky shots from a rifle (like an M1 Garand) can cripple significant capabilities on some of today's lightly armored ships. A (former) Navy friend of mine, an electronics guy, said five shots from close range (say, dockside) could reduce a destroyer's electronics (specifically radar) utility by nearly 100% if the shooter knew where to shoot.

I know some trade-offs are unavoidable, such as armor/speed/weight/fuel efficiency, but shifting too far one way is just as bad as shifting too far the other. Yes, electronics are force multipliers - they are also a weak point if you have no manual or properly redundant backup systems. Unless you are willing to bet your life your electronics are unhackable, or cannot be compromised (cough-Snowden-cough), having old-fashioned things like armor and guns on warships would seem prudent.

scipioamericanus said...

I'm sorry if my comment wasn't clear enough. I never said ships shouldn't have armor and guns, in fact I'm very adamant that they should be more survivable than they are now. While armor is one of the less effective ways to do that in the modern threat environment, protection against at least small arms and shell splinters is a must. Nor was I arguing for the primacy of electronics over other systems (i.e. I wasn't defending the Battle class) . My argument is that the number of weapons on a hull that can adequately be supported by the ship's infrastructure is often less than might seem appropriate to visual inspection.

The design overhead for things like putting in a pair of double-gun turrets instead of a single on-gun turret is enormous, not trivial, resulting not in quadruple the design resources (weight, volume, etc.) but typically much more as the increased requirements propagate nonlinearly through the rest of the ship.

There are all sorts of things, like survivably redundant wiring systems, increased internal subdivisions, and better protected magazines and fuel bunkerage, that ships like the Eilat sacrafice to free up the weight and volume for all those guns on the deck. Things that mean the difference between survival and death for the men who crew them.

Larry said...

Sadly, with the LCS, we're getting the worst of all worlds. Not enough endurance, very little armor, no redundancy, unable to survive a hit, not enough crew to even keep up with routine maintenance while underway, let alone enough to perform damage control after losing some percentage of the crew following a hit, none of promised mission modules, and yet they're still too big, AND hugely expensive. WTF?

scipioamericanus said...

Larry, all the things you mention LCS missing were sacrificed to the one factor you didn't mention, a factor which was pursued with singleminded (and some would say boneheaded) intensity by its designers: speed. The machinery to shove a 3000 t hull through sea-state 3 waters at 45+ kts takes up a completely disproportionate proportion of the LCS hull. With a design speed just 10 kts lower, it would have been a very different ship.

I have yet to hear a justification for that extra 10 kts, relevant to the modern threat environment, that justifies losing endurance, protection, weapons, sensors, crew capacity...

Larry said...

Yeah, that's the one thing it can do well: go fast -- when it's working. Methinks someone liked the opening scenes of Miami Vice too much. :)