The Navy officially accepted delivery of the USS North Dakota on Aug. 29, signalling the arrival of a new high-tech fast attack submarine equipped with improved missile tubes, computers, electronics and sonar technology.
Christened in November, the USS North Dakota will be the first of eight Block III Virginia-class boats delivered to the Navy, submarines engineered with a series of technological upgrades and innovations compared to earlier Blocks I and II boats, Navy officials said.
Blocks I and II, totaling 10 ships, have already been delivered to the Navy. All eight Block III boats are being built under a $14 billion Navy deal with General Dynamics’ Electric Boat from December of 2008.
The Block III subs are built with new so-called Virginia Payload Tubes designed to lower costs and increase missile-firing payload possibilities, Navy officials explained.
Instead of building what most existing Virginia-classsubmarines have — 12 individual 21-inch in diameter vertical launch tubes able to fire Tomahawk missiles — the Block III submarines are being built with two-larger 87-inch diameter tubes able to house six Tomahawk missiles each.
While primarily done to lower costs for the boat, this technical change will allow the possibility of future missiles and off-board sensors to be launched from the tubes, Navy officials said.
"North Dakota delivered ahead of schedule and under budget," Capt. David Goggins, Virginia Class program manager, said in a written statement. "When one considers the scope of design changes, this represents a tremendous achievement."
All Virginia-class submarines are also engineered with a computerized fly-by-wire touchscreen control system wherein boat operators use a joystick to navigate, unlike the mechanical hydraulic controls used on prior models.
The Block IIIboats also have a Large Aperture Bow array which places a conformal sonar system in the bow of the boat, Navy officials said.
“The LAB array provides improved passive listening capabilities over traditional spherical arrays employed on earlier submarines,” Rear Adm. Joseph Tofalo, director of undersea warfare, said in a written statement. “The LAB array includes a medium-frequency active array. The hydrophones used to determine a bearing of either incoming passive sounds or active reflected sounds are taken directly from previous design and technology advancements.”
Navy officials said that the North Dakota successfully completed Alpha, Bravo, and Board of Inspection and Survey trials, assessments which evaluate the submarine's seaworthiness and operational capabilities. During the trials, the crew took the submarine to test depth, conducted an emergency surfacing, and tested the submarine's propulsion plant, service officials said.
"North Dakota and her crew delivered an outstanding performance," Program Executive Officer for Submarines Rear Adm. David C. Johnson said in a written statement. "It was almost 10 years ago that the first ship of the class, USS Virginia delivered on Oct. 12, 2004. Since then, this program has delivered 10 ships, with North Dakota the latest. We continue to meet the Virginia Class standard of delivering submarines early, under cost, more complete and ready for tasking right out of the shipyard. North Dakota set a new benchmark for excellence in what is the arguably the best performing program in defense acquisition."
The Navy postponed North Dakota's original May commissioning date because of quality issues with vendor-assembled and delivered components that required an unplanned dry-docking to correct. Additional design certification work was also required on the submarine's redesigned bow, a Navy statement said.
"Now that certifications are complete, and we're armed with lessons learned," said Goggins, "we can move forward knowing that we are providing our fleet with the most capable, and battle-ready submarine possible."
The North Dakota is slated for commissioning on Oct. 25 in Groton, Connecticut.