What Was the Point of Building the Zumwalt Destroyer?

Sebastien Roblin

Security, Americas

These stealth ships need to be revised and the Navy needs to finally decide what to do with them.

Key point: These ships cost too much and cannot do what they were promised they could. Can they find a new purpose?

In January 2019, the Navy will commission its second hi-tech Zumwalt-class stealth destroyer, the USS Michael Monsoor. The third and last, USS Lyndon B. Johnson was launched this December 2018 and will be commissioned in 2022.

Traditionally, warships are tailored to perform specific missions. But the cutting-edge Zumwalt has been a ship in search of a mission, especially since procurement of hyper-expensive ammunition for its primary weapon system was canceled. Years and billions of dollars later, the Navy may finally have found one.

In the post-Cold War 1990s, the U.S Navy lacked peer competitors on the high seas, so it conceived its next-generation surface combatants for engaging coastal targets. As the Navy phased out its last battleship, it decided its next destroyer should mount long-range guns that could to provide more cost-efficient naval gunfire support than launching million-dollar Tomahawk cruise missiles.

In the 2000s, development proceeded for a DDG-1000 destroyer integrating every next-generation technology then conceivable. The Navy promised Congress a larger destroyer requiring only 95 crew instead of 300 thanks to automation, with adequate space and power-generation capacity to deploy railguns and laser weapons. The new warships would be stealthier to avoid enemy attacks and pack rapid-firing 6-inch guns with a range of 115 miles for the sustained bombardment of land targets. Thirty-two DDG-1000s were to succeed the Arleigh Burke-class destroyer.

The lead ship USS Zumwalt took shape sporting a futuristic-looking tumblehome hull—wider below the waterline than above—helping reduce the 190-meter long vessel’s radar cross-section to that of a small fishing boat. The ship’s induction motors generated a whopping 58 megawatts of electricity while cruising, enough to power the entire 17,630-ton ship thanks to an Integrated Power System. The electrically-driven motors and chilled exhaust also reduce the destroyer’s infrared and acoustic signature. The vessel’s new Total Ship Computing Environment networked all the destroyer’s systems, making them accessible from any console throughout the vessel.

In addition to rapid-firing 6” guns, the Zumwalt had eighty Mark 57 missile vertical-launch cells dispersed across her bow and stern to minimize secondary explosions. These could target and launch Tomahawk land-attack cruise missiles, ASROC anti-submarine rockets, or quad-packs of Evolved Sea Sparrow medium-range air-defense missiles. The Zumwalt’s spacious landing pad and hangar could accommodate up to three MQ-8B helicopter drones or two MH-60R helicopters, which can carry Hellfire anti-tank missiles or torpedoes. The destroyers also boast a capable dual-bandwidth sonar for hunting submarines, but lack the torpedo armament found in Arleigh Burkes.

The destroyer’s crew of one-hundred-and-fifty—plus a twenty-eight-person air detachment—exceeded by over 50 percent the originally promised number, but remained half that of an Arleigh-Burke destroyer. However, some analysts fear the super-trim crew complement leaves too little redundancy should the vessels sustain battle damage.

Indeed, by 2008, the Navy was no longer highly concerned with bombarding militarily weaker countries. Rather, it contemplated the challenge posed by China’s rapidly expanding surface and submarine fleets, and the proliferation of deadly anti-ship ballistic and cruise missiles.

Worse, the Zumwalt’s Advanced Gun System didn’t even work that well, with two-thirds the forecast range (around 70 miles). Furthermore, its rocket-boosted LRLAP GPS-guided shells cost $800,000 dollars each—nearly as expensive as more precise, longer-range and harder-hitting cruise missiles. The Navy finally canceled the insanely expensive munitions, leaving the Zumwalt with two huge guns it can’t fire.

Downsizing and Downgrades:        

Despite the well-known difficulties of developing next-generation military systems, the Zumwalt had been sold to Congress based on unrealistic minimum-cost estimates. Eventually, program costs exceeded the budget by 50 percent, triggering an automatic cancelation according to the Nunn—McCurdy Act.

Already by 2008, the Navy sought to ditch building more than two Zumwalts in favor of procuring Arleigh Burke Flight III destroyers with ballistic-missile defense capabilities. Maine Senator Susan Collins nonetheless wrangled a third destroyer to keep her state’s Bath Iron Works shipyard in business.

Each Zumwalt now costs $4.5 billion—in addition to the $10 billion spent on development. Like the troubled F-35 and Littoral Combat Ship, the Zumwalt’s spiraling costs were due to the Navy’s ambition to integrate completely new technologies still being concurrently developed. The final design was not even stabilized by the time construction began in 2009. The hybrid electrical system has proven especially challenging to integrate, leading the Zumwalt to break down while crossing the Panama Canal in November 2016.

Nearly decade after she was laid down, a 2018 Government Accountability Office report stated only five of the Zumwalt’s twelve key technologies was “mature.” Farcically, the ships were even officially “delivered” without combat systems. The lead ship, commissioned in 2012, won’t be ready for operational deployment until 2021.

The need to curb runaway costs led to crippling downgrades. Instead of fitting combining a powerful SPY-4 volume search radar with a SPY-3 hi-resolution targeting radar, the Navy ditched the former and rejigged the SPY-3 to handle volume-search as well. This saved $80 million per ship but significantly degraded air-search capabilities.

However, the Zumwalt currently only has Evolved Sea Sparrow air defense missiles with a range of thirty miles—adequate only for local coverage at best. Though the Zumwalt’s missile cells are compatible with longer-range Standard Missiles, those depend on the Aegis Combat System for guidance, which the Zumwalt lacks. And the Zumwalt’s last-ditch Close-In Weapon Systems were downgraded from 57-millimeter to much less capable 30-millimeter cannons.

Even the destroyer’s radar cross-section has been degraded to cut costs, with the adoption of cheaper steel for the deckhouse and the incorporation of non-flush sensor and communication masts.

Ship-Hunting Stealth Destroyers?:

What were merely three DDG-1000s good for, despite their nifty stealth features and propulsion? The advanced destroyers lacked ammunition for their guns, anti-ship missiles, anti-submarine torpedoes, and long-range area-air defense missiles. Furthermore, the Zumwalt had fewer cells to pack land-attack missiles than Arleigh-Burke destroyers (96), Ticonderoga-class cruisers (122), or Ohio-class cruise-missile submarines (144)—all of which were cheaper, and the last of which is stealthier.

Even the destroyer’s stealthy hull did not offer a clear advantage if it had to escort—or required an escort from—un-stealthy warships. And keeping a class of just three vessels operational meant very high overheads expenses in training and sustainment per individual ship. Thus, many analysts speculate the Zumwalt’s operational career could prove short-lived.

The Zumwalt needed a new mission—even if that meant tweaking its capabilities at an additional cost. Finally, in December 2017 the Navy announced the class would specialize in “surface strike”, i.e. hunting down other ships.

The destroyers will be modified to fire new Maritime Tomahawk Block IV subsonic anti-ship missiles and SM-6 active-radar-homing missile. The latter can provide longer-range air defense missile (up to 150 miles) and has a secondary ground or naval attack capability. Compared to the Tomahawk, the SM-6 has a much smaller 140-pound warhead, but its maximum speed of Mach 3.5 makes it much harder to intercept. Eventually, cheaper ammunition may be developed for the presently-useless guns, or they may be swapped out for additional missile launch cells or even future railguns or directed-energy weapons.

This surface warfare role may best leverage the Zumwalt’s stealth capabilities, allowing it to range ahead of the fleet and penetrate “anti-access” zones threatened by long-range anti-ship missiles. It could creep closer to enemy warships before launching its own missiles, giving adversaries little time to react.

The Navy is also working on networking sensors between its submarines, surface warships, helicopters, patrol planes and attack jets through “Cooperative Engagement” technology. Thus one strategy could see distant “spotter” generating targeting data using active radar, then transmitting it to a sensor-ghosting Zumwalt to perform the strike.

The cost of the current upgrades is reportedly $90 million—a sum which may prove worthwhile if it helps recoup some value after the $22 billion sunk into the ambitious but failed ship concept.

Sébastien Roblin holds a master’s degree in conflict resolution from Georgetown University and served as a university instructor for the Peace Corps in China. He has also worked in education, editing, and refugee resettlement in France and the United States. He currently writes on security and military history for War Is Boring. This first appeared earlier and is being reposted due to reader interest.

Image: Reuters.