Thursday, November 01, 2007

Reshaping the Destroyer

The American destroyer class of warship has undergone numerous changes since the first went to sea over a hundred years ago, especially in size. Notice the dramatic change in displacement weights for the following classes of Navy "tin cans" since the World War 2 era:

  • Fletcher (1942)-2050 tons
  • Gearing (1944)-2616 tons
  • Charles F. Adams (1958)-3277 tons
  • Spruance (1973)-6600 tons
  • Arleigh Burke (1989)-8230 tons
  • Zumwalt (2012?)-12,000 tons
Notice how the new destroyer is heading toward a ten-fold increase in size over its prewar ancestor. Generally, the explanation might be the need for newer weapons plus advanced propulsion and sensors expected from 21st century warships, but it also reveals how increasingly defensive the new ships are becoming as compared to their relative fighting power. The Aegis weapons system considered essential on US destroyers was created to track and defeat cruise missiles that are a threat to the battlefleet. Kevlar armor, armored missile launchers, and automatic guns are added to blunt the effects of a missile piercing the defensive screen.

History reveals that when a warship must carry so much defense in contrast to its offensive capability, it is headed toward obsolescence. The modern destroyer might be compared to the battleship, which by the Second World War loaded vast amounts of guns and ordinance specifically for defeating aircraft. Remarkably, between 1915 and 1945, the dreadnoughts doubled in size, with only a minor increase in the fighting power of its main guns.. Consider this example:
  • USS Wyoming 1910-Twelve 12"/50 guns in six twin turrets 26,000 tons
  • USS Iowa 1940-Nine 16"/50 guns in three triple turrets 45,000 tons
The difference in range of a 12 inch versus 16 inch gun is less than a few miles, while later aircraft and missiles could reach out in the hundreds of miles and more. Battleships were forced to load the extra protection because of its increased vulnerability to aircraft. Might we also draw the same conclusion, that if the destroyer is vulnerable to modern cruise missiles, her mission might soon be displaced by them?

In gun power, the 21st century destroyer is less well armed than its far less capable war era forebears, with two 5 inch guns against up to six on traditional vessels. It is in missile armament that the new ships shine, but it is questionable if they are more capable and cost efficient than other missile ships. A submarine carries numerous missile weapons as well as a destroyer, but is far less vulnerable to the same weapons. A submarine doesn't need Aegis, armor, or Standard missiles to defend itself. Likewise a small, stealthy attack boat, hiding in littoral waters could conceivably possess the same fighting power with long-range precision weapons as an 8000 ton destroyer.

Rather than adding the new weapons to our traditional warship designs, perhaps we should build around the new weapons. I'm reminded of the TV commercial in which a married couple asks a great architect to build a house around their unique looking bathroom faucet. We need to build ships to match their weapons, not new weapons for old ships.

The first US destroyer was the Bainbridge from 1903, weighing in at 420 tons. She was a single mission focused ship, designed to counter the threat new torpedo boats posed to the battlefleet. Later she proved an effective response to the submarine torpedo boat. Todays greyhounds are far removed from this essential duty, being so intent on defeating the air threat to herself or carriers, there is very little sea control duties left in her.

This is where the new littoral ships might come into favor. Going back to the drawing board, we would need a destroyer built to counter the threats of a new era, mainly that of terrorist pirates in littoral waters, and rogue states equipped with silent and deadly diesel/electric submarines, the latter possibly armed with cruise missiles. The 3000 ton American Littoral Combat Ship (LCS) is currently enduring many teething troubles trying to get it into service, but no more than any revolutionary weapon vying to prove its worth. A better and less costly design would be the Sea Fighter, at a third in price and size of the LCS which the Navy typically shows little interest in.

Numbers and affordability are the attraction of such small craft. Constructing them around new cruise missiles and unmanned vehicles, the Navy could go from there to build appropriate sized vessels that can keep up with the battlefleet, as long as we continue to adhere to a forward deployed, expeditionary strategy. My advice though, is keep it small and affordable.