By Geoff Fein

A major focus of the follow-on to the Trident (SSBN) submarines will need to be affordability, flexibility and underwater payload capacity, as well as taking lessons learned from the current Virginia-class build, according to a top Navy admiral.

"Clearly a major emphasis of the Sea Based Strategic Deterrent (SBSD), the follow-on to SSBN, will be affordability," Vice Adm. Jay Donnelly, commander of the submarine force, told Defense Daily, earlier this week at the annual Naval Submarine League symposium.

"The construction techniques we have developed and continue to hone on the Virginia-class, I think we’ll certainly apply those lessons learned to that next submarine class," he added.

Modular construction of the Virginia-class submarine has really worked well, Donnelly said.

"The ability to build those modules outside of the pressure hull and fully populate them, test them every way, and then insert them into a hull section, has saved us a lot of money and we are seeing greatly improved construction rates," he said. "The next design, whatever it turns out to be, we will try to leverage all of those good lessons we have learned from the Virginia class."

With the Navy’s focus on building modular ships that can be easily upgraded, and in the case of the Littoral Combat Ship, can be converted to carry out a number of different missions, could the Navy eye taking the SSGN concept and incorporate it onto SBSD? Donnelly said he wasn’t sure what lessons directly translate over to the next ballistic missile submarine.

But there is one lesson, he noted, that is very important-flexibility.

"Flexibility and underwater payload capacity are tremendous advantages," Donnelly said. "As we look at the AoA (Analysis of Alternatives) for SBSD and we begin to invest in 2010 in R&D (Research and Development), we will focus on flexibility for that platform…looking at various payload options and payload capacity for that platform, to give it as much flexibility as possible," he said.

Donnelly envisions SBSD having a service life of upward of 50 years. So with commissioning of the first SBSD in 2025, the first platform will likely last until 2075, he noted. "So flexibility and adaptability are going to be key to that platform."

While it’s impossible to determine with any certainty what the challenges are going to be to the nation out in the 2075 time frame, Donnelly said the Navy can make some reasonable assumptions. "The one thing that I think is for [certain] is the need for the platform [SBSD] is pretty well established."

"As long as nation states possess nuclear weapons, I think the U.S. will need a strategic deterrent to dissuade potential adversaries from using nuclear weapons against this nation," he said.

By basing those strategic deterrent weapons in a submarine, which has survivability, that gives the nation a much needed capability, Donnelly added. "I think with pretty good certainty, I can say we will need a SBSD."

Trying to determine what technologies will be out there 50 years from now that could threaten SBSD is difficult to say, Donnelly noted. But that’s why it’s important to build a submarine with flexibility.

"If you build a platform with some growth potential…with some flexibility, adaptability, we will cope with new technologies as they come along," he said.

With the Navy set to commission the USS New Hampshire (SSN-778) this weekend, and a contract for construction of the Block III Virginia-class boats expected by the end of the year, the Navy has been very, very happy with the progress of the program, Donnelly said.

"I think the beauty of that ship [is that] it was designed with a lot of capability. We have a fiber optic backbone that can carry a tremendous amount of information throughout the ship," he said. "We have that massive lock-in, lock-out chamber…we carry the ASDS (Advanced Seal Delivery System) and the dry deck shelter."

Changes to the torpedo room also demonstrate the advantages of flexibility in the Virginia-class ships, Donnelly noted.

"The reconfigurable torpedo room is a great example. You are no longer encumbered by the torpedo support facilities that we had on earlier classes," he said. "You have this large space in the torpedo room that you can use for a whole host of potential payloads that can go in and out of the torpedo tubes. Likewise on three of the Virginias, these large diameter tubes give you a lot of new payload capacity. It is very similar to what we can field on SSGN."

Each SSGN has one tube that can carry experimental payloads, Donnelly said.

"I think the potential of large diameter UUVs (unmanned underwater vehicles) is tremendous. We could put those in the large diameter tube on the SSGN," he said.

Those UUVs can go more than 1,000 miles out and for long periods of time, and are capable of conducting minefield reconnaissance or intelligence, surveillance and reconnaissance (ISR) operations, Donnelly said.

And UUVs could be used for harbor ISR too, he added. "You can let you imagination run with the payload that could go into very shallow water or areas a submarine just can’t go into," Donnelly said.

And if the Navy develops UUVs for SSGN, those systems would be adaptable to the same vertical launch tube found on the Virginia class.

"I think there is a future potential, especially with the reconfigurable torpedo room with those large diameter tubes," Donnelly said. "We could put new sensors on the ship that could give you a much greater awareness of the maritime domain."

One effort planned for the USS Florida (SSGN-728), one of four Ohio-class conversions from ballistic missile submarines to guided missile boats, is unmanned aerial vehicle operations from a submarine, Donnelly noted.

"We are modifying our [systems] so we can interface with Buster, a bungee cord-launched system that can reach an altitude of 1,000 feet. Buster will be equipped with an infrared (IR) camera and has a range of at least 20 miles, Donnelly told attendees at last year’s Naval Surface League conference (Defense Daily, Nov. 1).

Both the Florida and the USS Alexandria (SSN-757) have deployed Buster, Donnelly said on Wednesday.

"We don’t really need to launch it from a submarine as long as it’s in the air in an area where the submarine may be operating," he said. "If we can receive the down link…if we could re-task it to take a look at another area…and if we could use it in support of forces on the ground, and irregular warfare, and then when we are done with it we turn over control and another [station] can take it."

That concept of network centric operations, of controlling a UAV from a submarine, is the future the submarine force is looking at, Donnelly said.

"There’s no reason we couldn’t do that," he said. "We have actually proven that."

Donnelly pointed to the SSGNs. "We put a lot of communications capability on that ship. Now you’ll have to be at periscope depth with the current technology, and the mast has to be exposed, but that’s better than having to surface the ship and having to launch something with a bungee cord," he added.

Another area of focus for Donnelly is giving the submarine force to communicate at speed and depth.

"When I talk about communications at speed and depth , I would like to be to allow the submarine to operate at best depth necessary for its mission and still be able to share information," he said.

Having the capability to communicate at speed and depth would enable, for example, a Joint Task Force commander to tell a submarine [that is at depth] to stop what they are doing and re-task, because there is an aMQ-9 Reaper bound for their position that the submarine will need to take control of in support of ground operations that are currently in progress, Donnelly said.

"We could do that without having to wait for a very low frequency submarine broadcast, which is on a 12-hour schedule," he said.

Another more realistic scenario, Donnelly said, would be the ability of a Carrier Strike Group to notify a submarine at depth that an adversary has been detected and the submarine will need to reposition itself.

"They could immediately notify the submarine, and from depth [they could] acknowledge without having to come to the surface, stick up the mast, communicate and then go deep and reposition," Donnelly said. "It could really give the submarine a lot more agility without being forced to slow down to periscope depth."