As requirements grow for the proposed DDG-51 Arleigh Burke Flight III-class destroyers, so does concern that the U.S. Navy may try to pack too much into the ships and end up with a program that is behind schedule and over budget.

The ship was selected as the fastest and most affordable way to endow the Aegis defense system with enhanced ballistic missile defense (BMD) capability. And yet it is the need to field the radar necessary for BMD upgrades that is driving additional requirements for the DDG-51 Flight III.

The radar is the Navy's proposed Air and Missile Defense Radar (AMDR), which the U.S. Government Accountability Office says will cost the Navy $15.7 billion to develop and procure (DTI June, p. 28). The Navy needs the radar for simultaneous BMD and air defense at a level that is a magnitude better than what it will have with the Aegis upgrades planned through this decade.

The service conducted a hull-radar study that prompted it to reduce procurement of its most advanced destroyer, the DDG-1000 Zumwalt-class, to three from seven and restart the DDG-51 line. The Flight IIIs will be designed through the middle part of this decade because it is faster and more cost-effective to enhance the Aegis system and put AMDR on those ships than the Zumwalts.

“While our radar-hull study indicated that both DDG-51 and DDG-1000 were able to support our preferred radar systems,” Navy officials told Congress, “leveraging the DDG-51 hull was the most affordable option.” The estimated cost for two new DDG-51s is $3.5 billion, while the current price for each Zumwalt is a bit more than $3 billion.

The study is classified, but a former high-ranking Navy officer familiar with it said, “Some pieces of it got hijacked. People who had an agenda drove the study for a solution.”

Analysts and radar component competitors say the Navy pushed to restart the DDG-51 line because of pressure from Aegis supporters in the service to boost that program. Aegis contractor Lockheed Martin, though, denies that there was undue influence within the Navy. Moreover, as the Congressional Research Service (CRS) notes, Aegis warships are “suitable” for BMD because they carry a large arsenal of SM-3 interceptors—destroyers have 90-96 vertical launch system missile tubes, depending on their flight.

There's a growing worry, the CRS says, that the Navy will fall short of the number of Aegis-equipped ships it needs, especially for its BMD missions under the European Phased Adaptive Approach, which deploys vessels to European waters to defend allies from ballistic missile attacks.

There is also concern, CRS notes, “that demands from U.S. regional military commanders for Aegis ships for conducting BMD operations could strain the Navy's ability to provide regional military commanders with Aegis ships for non-BMD missions.”

The DDG-51 restart and Flight III procurement are intended to allay those concerns. The Navy's 30-year fiscal 2011-40 shipbuilding plan calls for procuring 24 Flight III DDG-51s from 2016-31.

“The 51 class is a top-shelf platform relative to other platforms,” says Mike Petters, CEO of Huntington Ingalls Industries (HII), which builds the ships. “It's such a good platform, the U.S. Navy decided to go back to it.”

But analysts, industry radar experts and even Navy officials acknowledge the Raytheon dual-band radar being developed for the Zumwalt (and for the Ford-class carrers) would have been tweaked just as easily for BMD. They also say the Zumwalt has other attributes—such as a lightweight composite deckhouse and integrated hybrid-electric propulsion system—that would have compensated for the AMDR's weight and appetite for power.

AMDR competitor Northrop Grumman is talking about using composites similar to those in the Zumwalt for its DDG-51 Flight III version. The company is teaming up with HII—the former Northrop Grumman shipbuilding unit building the DDG-1000 composite deckhouse as well as the DDG-51—for its AMDR bid.

And there is talk about developing a hybrid drive similar to the Zumwalt's to provide more power for the AMDR in Flight III.

Analysts and contractors say it's starting to appear that the Flight IIIs will be heavily modified to accommodate the AMDR. But the Navy's top shipbuilder executive warns against that course. “Sometimes we get caught up in the glamor of the high technology,” Petters says. “The radars get bounced around. They get changed. Their missions get changed . . . The challenge is if you let the radars drive the ships, you might not get any ships built.”