The Missile Defense Spectator

At Sea on an Aegis Destroyer

By From the October 2010 issue

Send to Kindle

The attack, when it came, developed fast.

The left-hand radar screen was displaying the coast of China; the right one, our own ship offshore, near Taiwan. Suddenly a streak rose from the launch area on the left, inland from the coast, on which our radar was focused.

"Here it comes," said the skipper, as the streak soared up in an arc, bending to the right, toward the sea.

We were sitting in the combat information center, called "Combat," deep inside a ballistic missile defense (BMD) destroyer. Although conceptually we were positioned in the Pacific, actually we were under way off the east coast of the U.S. Down in the dimly lit environment of Combat it made little difference as we gazed at the huge, brightly colored radar screens and watched the attack unfold.

Combat contains some 50 consoles, many displaying changing columns of figures, which tell you how an attack, and the ship's response, are progressing. Some 20 officers and enlisted personnel sit before these consoles, most with dozens of switches and buttons. Not all relate to the BMD functions. Other sections of Combat cope with defending the ship itself against surface, air, and underwater attack, and also with launching Tomahawk missiles against land targets and hostile ships. Land attack is under Washington's, not the ship's, control, and is thus highly secret, secluded in a corner.

As we watched, the attacking missile's rise was both plotted on the radar and described numerically on consoles. In this exercise it rose to 400,000 feet before starting its descent toward Hawaii. (You can calculate the target only after the boost phase.) After some minutes an interceptor missile rose from our ship and duly crashed into the attacking missile, which vanished from the radar display and from the numbers on the consoles. It had taken our missile about a minute and a half, traveling at about Mach 20, to climb up and make its "kinetic" or collision interception.

The Aegis system that performed this astonishing feat is called the SM (for standard missile)-3. This whole operation was an exercise, conceptual, but the real thing would have looked the same, down there in the somber precincts of Combat. It all happens so fast that the decisionsdetecting the attacking missile's launch, calculating its trajectory, generating the firing solution, and launching the shipboard SM-3 missile to interceptare made at lightning speed by computers, not by the destroyer's commander, who could not possibly decide fast enough. So you put the necessary general instructions and specific intelligence into the vast "SPY 1B" radar system and the SM-3's program, and then sit back and watch things unfold. These days the real-life SM-3 almost invariably hits an incoming missile. You do need a good idea of the launch sites, which one trusts will be available from our satellite monitors.

Whoops! The radar displays a foreign warship launching an attack on our destroyer. The captain turns to the tactical action officer, who manages fighting, sitting next to him on the right. "Kill ship," is all he says. The officer instantly transmits the word to the surface warfare coordinator and thence to the five-inch gun on deck, which rapidly fires five shells at the attacking ship. It vanishes in turn.

As usual, there is the measures-countermeasures alternation. A recent, somewhat hostile study in Arms Control Today claimed that the SM-3's missile often hits the rocket body instead of the warhead. That should throw the incoming warhead off its track, however. The study also points out the -problem of differentiating between incoming missiles and decoys, and coping with countermeasures the attacking missile could deploy. I was told that these problems will be solved.

An attacking aircraft would get much the same treatment from the two astonishing Phalanx Gatling guns on deck, which have their own self-correcting radar control and, bobbing about as the target direction varies, pour an almost solid stream of tungsten shells into the plane or missile.

Destroyers were originally built to sink sub-marines and, in some heroic situations, to fire torpedoes at larger ships, and they still have that capability, although it has been largely assigned to attack subs and torpedo boats. A BMD ship's main duty is thus shooting down ballistic missiles with the interception missiles it has on board. There are 61 of them, about 33 feet long, stored in 20 square-topped vertical "cells" under the foredeck and 61 under the afterdeck. (An Aegis cruiser, somewhat larger than a destroyer, has the same radar and missile system, but with 61 cells under the foredeck and 61 more aft. It also has two five-inch guns rather than the destroyer's one.)

A DDG multi-mission destroyer is 505 feet in overall length and when fully manned has "racks" for 350 sailors, including a handful of women officers and several dozen women enlisted personnel. The bridge is 56 feet up, and the masthead 154 feet. In addition to the ballistic missile exercises there are periodic man overboard and similar drills. (The symbolic victim carries an "O" flag and is thus called "Oscar"). Recovery takes several minutes, while the ship maneuvers to windward of the victim to create a lee, for easier recovery. Falling into the drink in the North Atlantic in cold weather is a very poor idea. Other drills involve the whole ship, such as its being hit conceptually by enemy fire, resulting in a conflagration on board and human casualties. Not much can happen in real combat that has not been simulated many, many times.

A yachtsman out on a destroyer is struck by the sight of our old "Don't Tread on Me" ensign on the bow until the ship gets under way, and by a -helmeted SCAT (Small Craft Action Team) with 762 mm machine guns on each flying bridge to fend off hostile small craft. Also, to reduce ambiguity, one says, "Come Right" (as distinct from starboard) although it's still the starboard beam.

The ship's displacement is 8,800 tons, and its engines put out 10,000 horsepower. All over its interior, at every operating station, there are two- to three-inch-thick manuals describing what must be done.

WHAT LIES AHEAD? The missile component of the Aegis system the SM-3 is entering service in improved versions as testing and research evolve under a 10-year "Phased Adaptive Approach." There are 30-some at sea already, including the entire Arleigh Burke-class of destroyers and three Ticonderoga-class cruisers.

Phase one, being deployed by next year, should be able to defend an area comparable in size to that between Philadelphia and Washington, D.C.

Phase two, to be deployed around 2015, and perhaps including airborne sensors, would defend an area at least three times larger.

Phase three, around 2018, should defend an area equivalent to all of Europe.

Phase four, around 2020, should provide boost-phase intercept capabilities for ICBMs targeting the United States.

The actual achievement of an important part of the "Star Wars" program has come about without general public awareness. The crux of the matter is that the program really does perform, almost infallibly, at a current cost of somewhat less than $2 billion a year. There are still limitations, which should be worked out in the successive phases. Right now, the biggest is that you need adequate information on where an impending launch is coming from. Satellite surveillance and other intelligence must provide this. Later on there will be airborne sensors, with wider systems to come.

The theory of ballistic missile defense is not to provide a perfect shield, but to degrade an attack to the point where it becomes unprofitable, as our riposte will infallibly ruin the attacking country. Since our situation with Russia has become more or less stable, we have had an understanding with them against -ballistic missile defense, but not against the inter-mediate range missiles that Iran, for instance, might deploy. If Iran develops an intercontinental capability, the Aegis can be adapted to protect against that. Our sea-based interceptors will be harder to knock out than land-based installations in Central Europe.

We are sharing the Aegis with Japan and Israel, both of which operate the system successfully. Other countries are scheduled to follow. Let us hope that this prodigious weapon discourages some unstable states from bothering to develop an attacking capability, quite aside from using it. 

Like this Article

Print this Article

Print Article