The Navy Stealth Battleship Strike Force May Not be Seaworthy
October 22, 2013
David Axe / War is Boring
The Navy's newest warships are hard to detect on radar, heavily armed with super-accurate guns and missiles … and giganti -- 600-feet long and displacing 15,000 tons, these Zumwalt-class destroyers are actually as big as some World War I battleships. But even a $7-billion stealth battleship has weaknesses. if a big wave hits from behind the vessel is prone to tumble and could capsize. The Zumwalts' most dangerous enemy could prove to be the sea itself.
WASHINGTON, DC (October 21, 2013) -- The Navy's newest warships are hard to detect on radar, heavily armed with super-accurate guns and missiles … and gigantic. Six-hundred-feet long and displacing 15,000 tons of water, the DDG-1000 Zumwalt-class ships are designated as destroyers but are actually as big as some World War I battleships.
The lead ship in the class is slated to launch any day now -- a milestone briefly delayed by the recent government shutdown. The Navy is building three of the Zumwalts over the next five years and deploying them to the Pacific to counter China's fast-improving military.
That's assuming the $7-billion-apiece Zumwalts don't simply capsize the first time a powerful wave strikes them from behind. The high-tech battleships feature a novel, downward-sloping "tumblehome" hull that's optimized for stealth -- not stability -- and lacks the wave-resisting qualities of traditional ships with upward-flaring hulls.
"On the DDG-1000, with the waves coming at you from behind, when a ship pitches down, it can lose transverse stability as the stern comes out of the water-and basically roll over," naval architect Ken Brower told Defense News.
Even if they don't sink in heavy seas, the Zumwalts are controversial vessels. Besides being by far the biggest and most expensive surface combatants in memory, the Zumwalts are actually inferior to older, smaller ships in certain key stats, in particular radar performance and missile capacity.
But what they lack in weapons and sensors, the new battleships make up for with other enhancements, including space for their own robotic air forces plus massive electrical output that, in the near future, could support powerful laser weapons.
The Zumwalts began as a 1990s naval fantasy. The sailing branch wanted to revamp its entire fleet of 100 frigates, destroyers and cruisers with a single basic design that could avoid radar detection, carry new sensors and weapons and be operated by a greatly reduced crew. The stealth design would be scaled upward or downward to replace 10,000-ton cruisers and destroyers and 4,000-ton frigates.
As with other military techno-fantasies of the '90s, the 21st-Century Surface Combatant initiative collapsed under the weight of its mounting cost and complexity. All that survives at present are a couple dozen small Littoral Combat Ships currently under construction plus the three Zumwalts. To keep its surface fleet numbers up, the Navy has decided to keep building the same Arleigh Burke-class destroyers it has been buying since the late 1980s.
So few in number, the Zumwalts will be niche, practically experimental vessels -- albeit with potentially powerful combat abilities. "What a tremendous ship!" Rear Adm. Thomas Rowden, the Navy's top shipbuilder, crowed to Defense Media Network. He described the Zumwalt class as "unique because it incorporates several innovative technologies into a multi-mission warship, including integrated power distribution, signature reduction, active and passive self-defense systems and enhanced survivability features."
Building the Battleships
In addition to the hard-to-detect tumblehome hull, the Zumwalts have smooth, angular superstructures that, in two of the three vessels, are made of composites instead of steel, further enhancing their stealth qualities. To save money, the Navy decided last week that the third and final Zumwalt will have a steel deckhouse made in Maine.
Huntington Ingalls Industries makes the 1,000-ton composite superstructure deckhouses in a special facility in Gulfport, Mississippi and ships them by barge to Bath Iron Works in Maine, where the ships are assembled and where they will be launched, one every couple of years starting later this year.
Rather than packing the vertical-launch missile cells into tight groupings fore and aft, as is typical, the Zumwalts carry their missile cells along the edge of the hull, effectively adding heft to their outside lines that can insulate them against enemy strikes.
But the unique layout decreases the overall missile arsenal from 96 large munitions in an Arleigh Burke to just 80 in a Zumwalt. Granted, the Sea Sparrow short-range self-defense missile comes in four-packs that fit inside a standard launch cell, so in theory, a Zumwalt could carry 320 Sea Sparrows.
But in practice the vessels will carry a mix of munitions including larger, one-per-cell SM-2 long-range air-defense missiles. In a divisive move, the Navy has opted not to give the new battleships the radar enhancement for deploying all the SM-2's modes, in particular its ability to hit incoming ballistic missiles.
Cost is one reason. The other reason is that the Zumwalts are primarily bombardment ships meant for sneaking up on and smashing targets on land. And for that they will carry scores of Tomahawk cruise missiles plus other high-tech weapons.
Each Zumwalt comes equipped with two 155-millimeter cannons made by BAE Systems and installed forward of the deckhouse in "holsters" that help them avoid radar detection. The guns are fed by automatic ammo systems that can deliver a 225-pound shell to each gun every six seconds until the 600-round magazine is depleted.
Boosted by rockets in their bottoms and steered by small fins, the shells can fly 62 miles to precisely hit GPS coordinates. But it's the possible future weapons that have the Navy really excited -- and that's got everything to do with the battleships' electrical power generation.
"It has the power margin," Rowden said. "It's an electric drive-ship, and the power generation capability it has is huge." At cruising speed, the Zumwalts produce 58 megawatts of excess power for weapons, sensors and other gear.
That electricity could power a laser gun. In 2010 Boeing completed initial design work on the so-called "Free Electron Laser Weapon System," a weapons-grade light beam. "The Free Electron Laser will use a ship's electrical power to create, in effect, unlimited ammunition and provide the ultra-precise, speed-of-light capability required to defend U.S. naval forces against emerging threats, such as hyper-velocity cruise missiles," Boeing veep Gary Fitzmire said.
An officer in the Pentagon's Office of Net Assessment told War is Boring that the Zumwalts would be perfect test platforms for the laser.
Based in San Diego starting in 2014, the Zumwalts will reinforce the Navy's Pacific Fleet as it stands up to an increasingly aggressive and well-armed China. Rowden said the battleships could sail alone, in groups with other surface ships or alongside aircraft carriers.
In America's ongoing campaign against Islamic terrorists or, God forbid, in some future shooting war with China, the Zumwalts could send Navy SEALs ashore by small boat or by one of the two Seahawk helicopters each carries. With their 11,000-square foot flight decks, the vessels can also support up to three Fire Scout drone helicopters for recon missions.
The commandos and drones could spot the targets and the Zumwalts could hit them with missiles and guns?-?and then fire missiles and possibly lasers to defend themselves from counter-attack.
But if a big wave hits from behind -- watch out. Even a $7-billion stealth battleship has weaknesses. The Zumwalts' most dangerous enemy could be the sea itself.
First published on Medium.com's War Is Boring collection.
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