FEATURE ARTICLE  

Navy Propulsion System Approaches Critical Stage 

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by Harold Kennedy 

Within the next 30 days or so, the U.S. Navy is scheduled to take a major step toward development of a futuristic new propulsion system that will substantially change the way that its ships are designed and built. That’s the plan, anyway, providing the Bush administration allows the controversial project to go forward.

By the first of April, the Navy intends to choose a single team of contractors to design and build the first of its Zumwalt-class 21st century land-attack destroyers (DD-21), which will include an electric-drive propulsion system, featuring an integrated power architecture.

The Navy decided last year to install electric drive in the DD-21. Making that change will be as important to the Navy as the transition "from sail to steam or from propeller to jet engines," according to Richard Danzig, who was Navy secretary at the time.

"Electric drive will reduce the cost, noise and maintenance demands of how our ships are driven," he said. "More importantly, electric drive—like other propulsion changes—will open immense opportunities for redesigning ship architecture, reducing manpower, improving shipboard life, reducing vulnerability and allocating a great deal more power to warfighting capability."

Because electric drive is significantly quieter than traditional propulsion systems, Navy officials explained, it increases a ship’s stealth capability, the ability to avoid enemy detection.

Electric drive is a transmission system, not an engine, Navy officials explained. The engine can be almost anything, a diesel, gas turbine or even steam turbine. Electric drive is a new way of transferring power from the engine to the rest of the ship.

A key design element of the new system is a single-source generator for all of the ship’s power needs—an integrated power system—including both propulsion and combat systems, officials said. This design eliminates the drive shaft and reduction gears found in traditional Navy ships, freeing up large amounts of internal space for other uses, such as habitat improvements.

Electric drive eventually will be used on most future Navy surface ships and submarines, officials said. Danzig announced last year that the first vessel to get the new system will be the DD-21.

The DD-21 is intended to be a multi-mission destroyer, designed specifically for land-attack warfare. One of its primary missions will be to support ground forces, the latest evolution in the way that destroyers have been used by the Navy.

Known as "greyhounds of the sea," destroyers first evolved a century ago to protect world shipping against an emerging class of small, fast torpedo boats. The first U.S. destroyer was the USS Bainbridge (DD-1), launched on August 27, 1901. In World Wars I and II, destroyers turned their weapons primarily against submarines. During the Cold War, guided missiles were added to their armament, greatly strengthening their ability to strike enemy aircraft, surface combatants and targets deep inland.

The DD-21 is intended to follow the Arleigh Burke (DDG-51) class of destroyers, which was first deployed in 1991. The Navy plans to build 58 of the DDG-51s, which feature the Aegis electronic combat system, before the end of the decade.

The DD-21 class of ships will be named for the late Navy Adm. Elmo Zumwalt, chief of naval operations from 1970 to 1974, the youngest man ever to hold that job.

The DD-21s are scheduled to replace the 1970s-era Spruance (DD-963) class of destroyers and Oliver Hazard Perry (FFG-7) class of frigates, both of which are reaching the ends of the service lives.

Blue and Gold
The Navy plans ultimately to build 32 DD-21s at an average cost of $750 million each for a total of about $25 billion. In coming weeks, the service aims to select a team of contractors to complete the design and build the first four ships. Construction of the lead ship is set to begin in 2005, with delivery in 2010. Two teams are competing for the contract:

Both teams are working separately to design their own electric-drive systems. The Blue Team’s effort is being led by General Dynamics’ Electric Boat shipyard, in Groton, Conn. The Gold Team is working with Newport News Shipbuilding, of Newport News, Va. Both teams are designing systems based upon permanent-magnet motors.

The two designs are being evaluated by the Navy’s Integrated Power System (IPS) Program Office, which is also working independently to integrate electric drive into the overall ship structure. "These systems have to be tailored to the ship’s design," IPS Program Manager Mike Collins, based in Arlington, Va., explained to National Defense.

Although electric drive has been used for years by cruise ships, the Navy has higher standards, Collins said. "DD-21 has to go further and quieter than any cruise ship," he noted.

Competition between the two teams is fierce. For the winning team, the contract "means significant income over the next several years," Thomas Bowler, BIW’s vice president for business development, told reporters at the recent Surface Navy Association symposium in Arlington, Va. The Navy plans to spend between $3 billion and $5 billion on research and development work for the DD-21.

After the first four ships are built, the Navy plans for the two teams to share the work of building the remaining 28 ships, as BIW and Ingalls have been sharing the construction work for the DDG-51s. Navy officials have concluded that such an arrangement is necessary to ensure the survival of at least two shipyards capable of building surface combatants.

With billions of dollars at stake, the two teams are playing their cards close to the chest. The Gold Team is saying little about its design until the Navy makes its decision. Because of the engineering requirements that the service is placing on both teams, however, the two designs look much alike, officials said.

Automation of many time-consuming crew assignments—such as maintenance, cleaning, damage control and even combat operations—will permit the crew to be reduced from 325 officers and enlisted personnel on DDG-51s to 95 or fewer on DD-21s, Bowler said.

Most of the reductions were made among junior enlisted personnel, he said. The DDG-51s have 250 E-5s and below, while the DD-21 will have less than 50.

Under the Blue Team concept, the DD-21 would be operated by four 15-person watch teams, working in a highly automated bridge and an advanced mission-control center (MCC), and using multi-modal workstations and task-managed prompting. The MCC would control the entire ship, replacing today’s combat-information center, sonar control, engineering-control center and damage-control center. The watch team could concentrate on strategy and tactics, making decisions on accurate and relevant information.

The four-section watch would provide "tremendous leverage in dealing with crew fatigue," Bowler said. It would enable all hands usually to get eight hours of uninterrupted sleep, even when the ship is underway.

The smaller crews and elimination of the ship’s drive shaft and reduction gears would open up more space that ship designers will be able to use to improve the quality of life for sailors on board.

"DD-21 will be the first ship designed for the sailor from the keel up," Bowler said. Traditionally, he noted, sailors on ships have been housed in large, open, poorly lit berthing compartments, with bunks stacked three or more high.

According to the Blue Team design, DD-21 sailors would live in staterooms, with a maximum of three people per room and individual privacy built into the design, Bowler explained. In these quarters, each sailor would have a personal computer, with e-mail, Internet connection and CD-ROM. In addition, each would have his or her own flat-screen television monitor mounted in the sleeping area.

The ship would have modern recreational facilities, including fitness centers, libraries and lounges. Drudge work, such as paint chipping and mess duty, would be eliminated.

The emphasis on individual privacy would make it easier to assign women to the DD-21, officials said. Women have served on surface combatant ships since the mid-1990s, they noted.

The smaller crews mean that fewer Navy personnel would be placed in harm’s way during combat. Because their role, during wartime, is to seek out and destroy enemy warships and other military targets, destroyers often suffer heavy casualties. During World War II, more than 70 U.S. destroyers were sunk. The USS Cole lost 17 sailors last year to a terrorist assault in Yemen.

Survivability
The DD-21 is being designed to increase its chances—and those of its crew—of surviving such attacks. Blue Team proposals, in addition to increased stealth, include a shock-resistant double hull, a robust electrical system and an integrated magazine protection system.

"Zonal distribution and redundancies will ensure that the loss of no single space will cripple the ship," Bowler said.

Automated damage-control operations would include robotic fire-fighting technology, with built-in sensors able to preconfigure and reconfigure systems for combat. They would monitor equipment status and detect smoke, fire and flooding.

In the event of damage, the first response would be through the Ship Systems Automation (SSA), Bowler explained. "SSA detects, isolates and contains damage much more effectively than conventional approaches," he said.

Automation would be augmented by rapid-response teams who will have the equipment and skills to handle any event, Bowler said. Guided by a readiness-control officer in the mission-control center, the teams would use sensors, wireless communication, wearable computers or mini-cams and personal location devices to gain and maintain situational awareness.

DD-21 will be the first class of destroyers designed "to operate in the littorals, rather than in blue water," and to concentrate on land targets, rather than ocean-going ones, Bowler said. Its weapons package will feature:

In addition, the Navy is making plans to insert new weapons systems, such as laser technology and electric guns, as they become available, noted Kendall Pease, vice president for communications at General Dynamics in Falls Church, Va.

"As soon as the procurement process for this ship gets under way, they’ll be coming out of the woodwork with new weapons systems for it," Pease told reporters. "What makes all of this possible is electric drive."

What remains to be seen, however, is just how much support DD-21—and electric drive—will receive from the Bush administration. During his election campaign, President Bush promised to transform U.S. military services, placing "a new and greater emphasis on research and development (R&D)."

In a speech at the Citadel, in South Carolina, he pledged to increase spending for defense-related R&D by $20 billion "between the time I take office and 2006." He also promised to "earmark at least 20 percent of the procurement budget for acquisition programs that propel America generations ahead in military technology." In addition, Bush proposed "to skip a generation of technology" in order to introduce truly revolutionary weapons systems.

As a particularly promising idea, he singled out the arsenal ship, a discarded concept that shared many of the characteristics of the DD-21—a stealthy vessel, packed with long-range missiles to destroy targets from great distances.

Long List
The problem is that the DD-21 is just one of a long list of new weapons systems under Pentagon consideration. These include a national missile-defense system, three tactical fighter aircraft and new Army vehicles.

And the Navy wants to bolster its aging fleet by building, in addition to the DD-21, more Arleigh Burke-class destroyers and whole new generations of aircraft carriers, submarines and amphibious assault ships.

Developing all of this hardware, some officials have estimated, could add as much as $100 billion a year to the current $300 billion defense budget. Yet, in his campaign, Bush proposed defense-spending increases of only $4.5 billion per year.

This means, according to industry insiders, that some major programs may have to be canceled or postponed. High on that list, they said, is the DD-21.

For one thing, they noted, the DD-21 is still in the early planning stages, while the F-22 fighter, MV-22 Osprey tiltrotor and Joint Strike Fighter are already flying.

Also, some analysts have argued that the DD-21 is unnecessary. Navy Vice Adm. Arthur Cebrowski, president of the Naval War College in Newport, R.I., has proposed instead to build a class of small, heavily-armed ships called "street fighter," capable of speeds up to 60 knots. That is twice the planned speed of the DD-21. Such a ship, Cebrowksi said, would operate better in offshore waters than the DD-21.

Submarine advocates, such as Sen. Joseph Lieberman, D-Conn., have proposed giving the land-attack mission to Trident ballistic-missile submarines. They have suggested refitting four of them, which are headed for retirement, with Tomahawk cruise missiles, which can fire as far as 1,000 miles inland.

Retired Navy Rear Adm. Eugene Carroll, vice president of the Center For Defense Information, of Washington, D.C., questions the value of electric drive technology. "I have yet to be sold on it," he told National Defense. It seems to him, the former aviator said, that electric drive simply puts one more step "between the power and the screws."

Carroll also has deep reservations about DD-21, which he describes as "simply the Navy’s means of competing with the Air Force for the deep-strike mission."

The Navy "no longer has to fight for control of the sea," Carroll said. "There’s nobody out there to fight any more."

Navy officials, at press time, said they continue to support development of DD-21. The fiscal year 2002 budget request that the Navy plans to submit to Defense Secretary Donald H. Rumsfeld "contains full funding for DD-21," according to Jon Walman, head of public affairs for the Program Executive Office for Surface Strike, in Arlington, Va.

At the recent Surface Navy Association meeting, Navy Chief of Naval Operations Adm. Vern Clark renewed his commitment to the ship. "I want what DD-21 brings to us, and we need it," he told the audience.

Particularly attractive to the Navy is the Blue Team claim that its design will reduce operations and support costs for the ship by 42 percent.

"That’s billions and billions of dollars that the Navy and the taxpayer can use for other purposes," said Mike Hughes, a Lockheed Martin vice president.

For the time being, all that those involved in the DD-21 project can do is wait until the Bush administration’s 2002 budget request is released, perhaps as late as April, to see what happens.

"It probably depends on what the CNO wants to do," said Pease. "It all depends on the bottom line. Given a blank check, this is a super program. It needs real leadership."

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