There may be rough seas ahead for the Navy's ballistic missile defense force.

Demands are high for the Navy's BMD-capable ships and, soon, land sites, and for good reason. More than 1,200 ballistic missiles have been added to the arsenals of potential adversaries in the past five years, according to the Missile Defense Agency.

North Korea, Syria and Iran are making strides in development and production, with Iran ready as soon as this year to test an intercontinental ballistic missile capable of reaching the United States, according to reports by the National Air and Space Intelligence Center.

As this new arms race threatens American allies, 33 ships — five cruisers and 28 destroyers — are standing on point to deter any such attack. Ships armed with ballistic missile defense radars and interceptors are among the fleet's most in-demand vessels, whether in the Asia-Pacific or European waters.

And those crews have paid a price. The former head of Fleet Forces Command, Adm. Bill Gortney, said the ballistic missile defense armada is "the most stressed [and has] the highest operational tempo of all our forces." The new FFC boss is working to cut deployments of stateside BMD-ships to seven-and-a-half months.

Despite the increasing threat, the Pentagon plans to lay up four of the fleet's newest ships, and the remaining gray hulls are faced with increasing maintenance issues.

Ships armed with ballistic missile defense radars and interceptors are among the fleet's most in-demand vessels, whether in the Asia-Pacific or European waters.

There are 16 BMD-capable ships on the West Coast, which includes five ships forward-deployed to Yokosuka, Japan. Another 17 BMD-capable ships are on the East Coast, which includes two destroyers forward deployed to Rota, Spain. Two more destroyers, the Carney and the Porter, will relocate to Rota by October, where ships will be set to go on four-month BMD patrols.

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But these BMD-ships are ships hardly immune from the upkeep problems that have hampered the rest of the fleet.

BMD ships are part of the 36-month Optimized-Fleet Response Plan, which is geared to cut deployments to seven months. It starts with a maintenance phase scheduled to last roughly 24 weeks. Maintenance periods on BMD ships are running anywhere from 20 to 51 weeks, according to Chris Johnson, spokesman for Naval Sea Systems Command. Ten of the 33 BMD ships are in availability periods in private shipyards, and half have been extended for reasons other than BMD upgrades. The extensions ranged from seven to 82 days, with some stretching longer.

Consider the cruiser Monterey, which entered BAE Systems Norfolk Ship Repair in 2014. The cruiser was supposed to come out of the yard in November and join the Eisenhower carrier strike group in the spring. But the issues ran deep , and the dry-dock period was extended through January. BAE Systems, which was awarded $57 million for maintenance and upgrades, found five cracks in the superstructure. The Navy now says the ship will be ready in March. Sailors working alongside shipyard contractors said they would be surprised if it leaves before summer.

Spokespeople for BAE Systems Norfolk Ship Repair did not respond to calls seeking comment by Jan. 30.

The deployment cycle is founded on predictable overhauls, after which the ship enters work-ups and then deployments. Overhauls missed or extended risk unraveling the predictability that is at the focus of the new deployment scheme .

Right now, BMD deployments are running about 7.5 months, which is better than carrier strike groups. The Theodore Roosevelt CSG, for example, will deploy for 8.5 months in the spring.

"These ships are getting older," said one chief, who asked to remain anonymous because he was not authorized to speak on the issue. "It is taking longer to fix them. It only takes one or two big issues to throw a wrench in the whole system, and that will affect every BMD ship down the line.

"This mission doesn't get a lot of headlines, but it is probably one of the most important ones out there," he added.

The Navy plans to increase the BMD fleet to 43 ships by 2019. But some of those ships will be sidelined as the Navy moves to put 11 cruisers into layup pierside, to include four BMD-capable cruisers: Shiloh, Lake Erie, Vella Gulf and Port Royal. Those would not return to service until 2024, 2026, 2027, and 2027, respectively. Late last year, the Navy got the go ahead from lawmakers to lay up two cruisers.

Only 18 BMD ships are needed to consistently meet current strategies and commitments, according to Bryan Clark, a senior fellow at the Center for Strategic and Budgetary Assessments who previously served as special assistant to the chief of naval operations. The Navy has just over 20 at any given time, so an increase of even six (instead of 10) would provide a considerable cushion. But demand is quickly increasing as foreign militaries spend billions to build larger ballistic and cruise missile inventories, and analysts are not confident an increase of six BMD ships would keep pace.

The magnitude of the threat led the Missile Defense Agency to boost procurement by one-third, to $2 billion, by 2019, but not all of this money will be funneled to the Navy. The Ballistic Missile Defense System also supports ground-based interceptors for homeland defense, forward-based Army-Navy Transportable Radar Surveillance & Control-Series 2 radars, and Terminal High-Altitude Area Defense, or THAAD, batteries.

Aegis ashore

As it turns out, it may be land-based systems that keep the BMD Navy from running aground.

The Navy's BMD-force is also setting up shore sites.

Aegis Ashore facilities will help meet the increasing demand in Europe, said Lt. Cmdr. Cate Cook, Fleet Forces Command spokeswoman. The first is Naval Support Facility Deveselu, Romania. The 430-acre site will be operational at the end of 2015 and manned by about 200 U.S. service members, government civilians and support contractors. It will be armed with SM-3 IB interceptors. The second site will be in Poland. It is scheduled to be operational in 2018, and will be armed with SM-3 IIA interceptors.

Still, the numbers are not in favor of a small BMD fleet. Each Aegis Ashore system includes a magazine of just 24 interceptors. Those could be overwhelmed if adversaries develop more advanced missile systems or if they fire large salvos, experts say.

One solution is siting more Aegis Ashore systems, according to Clark, the CSBA defense expert. An Aegis Ashore system costs $750 million, as compared to $1.6 billion for a Flight IIA destroyer or $1.9 billion for a Flight III. Fixed BMD sites will not only help meet this emerging threat, but will allow more ships to return to offensive missions that have become neglected, Clark argued in his Nov. 24 analysis, "Commanding the Seas: A Plan to Reinvigorate U.S. Navy Surface Warfare."

The Missile Defense Agency is looking to improve early intercept capabilities and bring more allies into the mix to help ease the burden. Officials are also investing in technologies like lasers that could one day prove integral to missile shields.