By Geoff Fein
Exercise Bold Monarch 08 not only offered the Navy an opportunity to collaborate with international navies on honing submarine rescue skills, but the two-week event enabled the Navy to conduct operational evaluation of the Submarine Rescue Diving Recompression System (SRDRS).
SRDRS is the newest platform for evacuating and rescuing sailors from downed submarines. It is replacing the more than 30-year-old Deep Submergence Rescue Vehicle (DSRV).
Unlike DSRV, which was an autonomous system, SRDRS will be tethered to a surface ship, and piloted from that ship, Capt. Gary Dunlap, program manager for the Advanced Undersea Systems Program office, told Defense Daily in a recent interview.
“That tether provides command and control, communications, and power down to the rescue vehicle,” he said.
Two sailors will be aboard SRDRS to assist with the final mating of the rescue vehicle and the submarine, and they will assist with the rescue of sailors, Dunlap added.
The decision to go from the autonomous DSRV to the tethered SRDRS will help reduce the rescue vehicle’s complexity to a large extent, Dunlap said.
“For instance, on the DSRV, it needed to have its own power source. When you went down and did a rescue you had to have a two-hour battery recharge,” he said. “[With SRDRS] you have none of that concern, so the cycle time is a bit quicker.”
SRDRS is part of a three phase acquisition effort. Phase one was called the assessment underwater work system–an atmospheric dive suit, Dunlap said.
“We fly that component of the system out first, and [divers] go down and localize the disabled submarine,” he said. “They make sure it’s a clear deck so that when the rescue capable piece shows up the mating surface is clear so that they can go ahead and mate and rescue.”
The suits are new, Dunlap explained. “In the past we had essentially an ROV (remotely operated vehicle) that would go down and verify that everything was clear before putting down the DSRV. We are transitioning from that to this manned suit to provide more capability in that area.”
The Navy has three of those suits, he noted. In a rescue, the Navy would deploy two suits for redundancy. “We have a maintenance plan that keeps them online where we roll one suit at a time back up to Vancouver for periodic maintenance.”
OceanWorks International, in Vancouver, Canada, won the competition to build the dive suits and SRDRS, Dunlap said.
“They worked on initial design and fabrication [of SRDRS]. We received the system last November and have worked through testing and certification as we went through Bold Monarch,” Dunlap said.
SRDRS has a lot of commercial-off-the-shelf components to the maximum extent possible, he added. “That allowed it to be more sustainable across its life. The system is expected to be online for a generation, like its predecessor.”
SRDRS is a bit less complex than DSRV because all of the command and control was moved into a control van that is located on the back of the support ship, Dunlap noted.
Another feature of SRDRS is the transfer skirt. The operator in the control van can rotate the transfer skirt 360-degrees to accommodate submarines that are on different angles at the bottom of the ocean, while at the same time keeping the rescue vehicle horizontal.
“This just simplifies the operation and makes it safer as the two sailors try to transfer the folks [into SRDRS] for return to the surface,” Dunlap added.
The third phase of the acquisition is a follow-on piece of the system, which is above and beyond the capability the Navy has today–a submarine decompression chamber, Dunlap said.
“One of the concerns when you have a disabled submarine is that the pressure tends to increase over time…you have air venting inboard, etc.,” he said.
The decompression system is being built by Hanover, Md.-based Oceaneering International.
The SRDRS program began back in 1998 and will end with delivery of phase three in 2012. “It’s going to have an estimated completion cost of $160 million, and that includes all the design, fabrication, test and fielding of this first system,” Dunlap added.
When SRDRS comes online, DSRV will be deactivated and maintained at the Deep Submergence unit at North Island, San Diego, he said.
Operation and maintenance will also change when SRDRS comes online. SRDRS will be government owned, but contractor operated and maintained. The new approach makes any idea of having both DSRV and SRDRS operational at the same time inefficient, Dunlap said.
“To try to have both of those [systems] online throughout the life would not be very cost effective,” he said. “And DSRV, from a logistics point, you reach a point where things are obsolete and just keeping her online becomes very cost [inefficient].”
There are two operational scenarios that SRDRS is out there to support, Dunlap said. “The first one is actually a heightened state of readiness, what we call [the] mod alert period.”
Whenever new construction submarines leave General Dynamics [GD] Electric Boat or Northrop Grumman [NOC] Newport News for their sea trials, or whenever an in-service submarine heads back out after a major depot maintenance level period, SRDRS is in a heightened state of readiness, Dunlap said.
“While that submarine is out doing that piece of work…[after] you have done so much maintenance…that is probably the most sensitive time in a submarine’s operational life,” he explained. “We plan the maintenance to be available for those mod alert periods. There are about six to eight of those a year.”
The second operational scenario for the overall rescue system is to just be ready for a rescue 24/7, Dunlap said.
“If [SRDRS] happened to be in a maintenance period when a real rescue would be required, in that case we would be accelerating action to get her back online, and really leverage our relationships with the international submarine rescue community,” Dunlap pointed out. “And that’s why it is so important to have these exercises. We’ll leverage the NATO system or others across the world and vice versa. It’s really an international action.”
NATO has the Submarine Rescue System (NSRS) that will also go online later this year (Defense Daily, June 16).
Having the ability to call on international rescue systems lessens the need for more than one U.S. system, Dunlap noted.
“It’s a great example to show where international cooperation…international capability is key to success,” he said.