Notes: After the USN decided in 1993 that the expensive Seawolf class would end at just three hulls, work began on a follow-on to the Los Angeles class. Originally codenamed “Centurion”, and later “New SSN (NSSN) Project”, the leadship of these powerful submarines was named Virginia.
The type was to be proficient in both open-ocean and coastal operations, with an emphasis on SPECOPS. Most importantly, cost was to be a limiting factor. Early diagrams showed exotic features such as a sail resembling the Soviet Alfa class and an underwater vehicle hangar. None of these made it to the final design, which basically resembles a slightly larger Flight III Los Angeles class.
(early “Project Centurion” concept)
The internal pressure hull structure is centered around 19”x24” integrated enclosures, for modular replacement of equipment throughout the subs’ lifetimes. Sound isolation is extensive, for example the control room is a single rafted structure. Because of the non-penetrating masts, the designers were free to relocate the control room from underneath the sail. In contrast with all earlier SSNs, the Virginias are “flown” by a fighter-style joystick. Many controls are of the digital touch-screen type. The sonar room is eliminated and the operators are now stationed in the control room. The AN/BQQ-10 is a modified AN/BSY-1 as used on late-model Los Angeles class subs.
The hull returns to the HY-80 type of steel after use of HY-100 on the Seawolfs. The sub is coated in anechoic coating and the Virginias are said to be as quiet as the Russian Akula class. The sonar dome and much of the sail are constructed of composites.
A watertight compartment aft of the operations room encompassing the entire upper level is dedicated to SEAL operations. The entire compartment can be locked-out and flooded, and also houses zodiacs and swimmer delivery vehicles. Additional small lockers for commando gear are located in the sail. The entire torpedo room can be reconfigured into a berthing space for 30 troops, if so desired.
(A Virginia-class SSN under construction at Electric Boat in Groton, CT. Note the exposed spherical bow sonar array, open VLS launch tubes, exposed close-contact array in the sail, and the shrouded PJP at the stern.)
The ships are named after states of the union (previously, assigned to SSBNs and before that CGNs and BBs), however there is a movement underway to name one of the Virginia class subs “Monitor” to honour the Civil War duel between CSS Virginia and USS Monitor.
The major factor affecting the class is cost; by May 2007 it had risen from the initial $1.5 billion estimate to $2.3 billion (more than a Seawolf, which it was intended as a cheaper alternative to) each. To keep both Electric Boat and Newport News in the submarine business, production of each sub is split between the two companies; with primary responsibility alternating with each hull. The catch-22 is that the per-hull is too much to build more than one per year; yet; unless two per year are built, this expensive split arrangement must be maintained. The Tango Bravo project (see below) is addressing this. In late 2010, the USN claimed that it had successfully reversed the cost overruns, with USS New Hampshire and USS New Mexico being delivered beneath the builder's original estimates.
Displacement: 6950t surfaced, 7800t submerged Dimensions: 377’x34’x30.5’ Machinery: Nuclear: 1 General Electric S9G PWR, 2 reduction-geared steam turbines, 1 shaft with United Defense PJP. 1 Caterpillar 3512D diesel/lead-acid battery backup, 1 electric motor + 1 SPM (retractable outboard, max speed 3kts) Max speed: 32kts submerged, 25kts surfaced Diving depth: officially 800’, est. 1200’ max Range: essentially unlimited, avg. submerged endurance 90 days Complement: 134 (14 officers, 120 enlisted); typically only 113 embarked
x12 21” external VLS for UGM-109 Tomahawks + x4 21” tubes for 28 total internal weapons: Mk48 ADCAP torpedoes, Mk60 CAPTOR mines, I-SLMM mines (planned), UGM-84D Harpoon anti-ship missiles (not currently embarked) or additional UGM-109 Tomahawks. Boeing LMRS tube-launched minesweeping system currently being evaluated.
AN/BPS-16 (X) 35NM surface search/19NM low-alt air search (range, bearing)
x2 AN/BVS-1 photonic non-penetrating masts
AN/BLQ-10 integrated EW/ESM/ELINT/SIGINT system
AN/BQQ-10(V) combined active/passive suite: (spherical AN/BQQ-6 array, chin-mounted AMDS active array, close-contact sail array, WAA passive hull arrays) Range classified.
TB-16 towed array
TB-29A “thin line” towed array
AN/BRA-34 (x2) comms mast, OE-315 towed wire antenna
“TANGO BRAVO” PROJECT
To achieve the desired two-hull-annual build rate, the USN began “Project Tango Bravo” in 2005. Three areas were identified: 1) Reducing the number of systems, 2) Reducing the complexity of systems, and 2) Reducing the overall amount of metal used (HY-80 has tripled in price since Virginia was designed); all of which would reduce construction costs; and overall reductions in the life-cycle costs of the sub. The results were to be applied to the final Flight III hulls (SSN-784 through SSN-791). The study recommended several extreme modifications to the Virginia class:
1) Replacing the PJP with propellers from decommissioning Los Angeles class units. The advantage would be construction cost savings. The disadvantage would be a much louder submarine.
2) Electric engine. By far the most radical idea is replacing the engine room with a non-penetrating electric motor located outside the pressure hull. The advantages would be elimination of the reduction gears, shaft, bearings, valves, and shaft seals resulting in both lower construction and life-cycle costs; plus a shortening of the aft compartment resulting in less metal for even more construction savings. Manning could be reduced as well. The extreme disadvantage is that if the external motor failed, the crew would have no way of repairing it. This idea is extremely controversial. In July 2006, Electric Boat was awarded a contract to begin design on such an engine.
3) Eliminating the SPECOPS compartment. The advantages would be lower construction costs due to metal savings because of the shorter hull. This would be an extremely hard pitch to Congress, as the SPECOPS compartment was the main “selling point” of the Virginia in the first place, now the USN would have to find a way to explain it away as unnecessary.
4) Replacing the spherical array with conformal arrays wrapped around the bow. This would result in significant construction and life-cycle costs, the USN is definitely proceeding with this item (see below).
5) Eliminating one of the towed arrays. The advantage would be lower construction costs. The disadvantage would be loss of some sonar abilities.
6) Transitional Technology Core. Currently, refueling is the single-largest life-cycle cost; so much in fact that the USN prematurely retired several Los Angeles class units rather than pay for their refueling. Powered by recycled nuclear weapons Uranium, the TTC reactor design is intended to give 30 years’ (the Virginia’s estimated max hull life) steaming with no refueling. Additionally, it’s intended to be paired with an electro-centric ship (as in the Zumwalt class destroyers); replacing many pneumatic and hydraulic valves, vents, and fixtures with small electric motors. There is no real disadvantage to this, assuming the TTC can be perfected.
7) External weapons. It has been proposed to replace the torpedo room with modular launchers located outside the pressure hull. The advantage would be reduced construction (tubes, flood down tanks, doors) and life-cycle (maintenance and manning) costs; additionally, the former torpedo room could be used for other tasks. In June 2005, Newport News began work on such a system, the prototype of which was completed in March 2007 (see below). Later in 2007 Newport News was awarded $12.7 million for advanced trials of the system.
It now appears that some of the more exotic features will not be proceeded with. However in May 2008 the USN announced it had decided to use the conformal bow array in place of the sonar sphere; as described above. Also announced was that the Flight III subs would have their VLS replaced by two SSBN-sized vertical tubes housing the multiple-round UGM-109 Tomahawk launchers, as carried by the Ohio class SSGN conversions. Together, these two changes will shave $19 million off the cost of each Flight III sub and also lower the life-cycle costs. In November 2010, the USN announced it had achieved funding and planning to do a 2-per-year build for the remaining Virginia class subs even without the Tango Bravo changes.