How to build a $2.7B nuclear submarine

There's a lot going on with the Navy's next generation of nuclear subs, the Virginia class. Instead of traditional periscopes, think telescoping photonic sensors. Instead of blade-powered propulsion, think pump jets.

We've got a sneak peak of the construction going on for the next batch of Virginias in the works, Block III. That includes the USS Washington, which was christened earlier this year, but has yet to swim the high seas.

When complete, these submarines will be the latest in the Virginia class, joining the ranks of earlier-block vessels such as USS Texas (SSN 775).

A crawler transports a unit for the Virginia-class submarine Washington (SSN 787) after it arrives at Newport News Shipbuilding on a shuttle.

The Navy christened the ship in March and launched it in April, but the sub has yet to be formally commissioned.

Here is the newly completed pressure hull of the Washington. The periscope-replacing photonics masts will go outside this hull.

A photonics mast telescopes up above the water in the same manner as a car antenna. It delivers information through an array of sensors, including high definition low-light and thermographic cameras.

From above, the Washington will look much like this sub, the North Dakota, another Block III vessel commissioned in 2014.

Here's a piece of the Washington inside the 10-story Huntington-Ingalls Modular Outfitting Facility. The future of Navy subs is all about modular components.

A Virginia-class submarine propulsor bolting face is machined on a ring lathe at Newport News Shipbuiding.

In contrast to a traditional bladed propeller, Virginia-class subs use pump-jet propulsors, which are quieter and reduce the risk of unwanted gas bubbles.

The capabilities of next-gem subs are breathtaking. This handout image illustrates them all.

Newport News Shipbuilding is in charge of building the stern, habitability and machinery spaces, torpedo room, sail and bow for Virginia-class subs.

Newport News Shipbuilding welder Juna Claudio works on the Washington.

Newport News Shipbuilding riggers Christopher Parrish (in the gray sweatshirt) and Henry Dillard (in a red shirt) fit a charcoal filter to the fan room for the Virginia-class submarine Indiana. Ricky Campbell, inside the unit, waits to clamp the filter into position.

The Indiana was laid down in 2014 but has yet to be christened or officially commissioned.

Shipbuilders Nico Brinkley (left) and Andrew Yonta install a welding track on a unit for the Washington, launched in April.

The crest of the Washington features images of Mount Rainier, the Seattle skyline, evergreen trees and silhouettes of the previous two USS Washington ships.

The bow section of Virginia-class submarine Illinois (SSN 786) is moved to the river to be transported. It was christened in October 2015 by First Lady Michelle Obama, but it still officially under construction.

Tanya Downing inspects a label in the habitability space of Washington.

The bow units of Washington and Colorado (SSN 788) fill one side of the Supplemental Modular Outfitting Facility. The facility itself is impressive: 65,000 square feet of production area and four main bays for construction, as well as 17 specialized work spaces, offices and areas for lunch breaks.

A panorama of Newport News Shipbuilding taken from the Floating Dry Dock showing (left to right) USS Abraham Lincoln (CVN 72); the bow unit of Illinois being moved to a sea shuttle; Gerald R. Ford (CVN 78) undergoing final outfitting, and USS Enterprise (CVN 65) undergoing inactivation.

Shipbuilders work on a unit of Virginia-class submarine SSN 793.

Welder Jimmie Mosely works in the Supplemental Modular Outfitting Facility on the submarine Washington.

Mike Bishop, left, and Daniel Evans fit a plate on a diving plane for Indiana. Diving planes, sometimes called hydroplanes, allow the vessel to pitch its bow and stern up or down...all the better to surface or submerge.

John Schiavone applies the dye for a Dye Penetration Test on a South Dakota (SSN 790) torpedo tube shutter door. The tests suss out cracks or weaknesses in a surface.

Master Shipbuilder Elmer Lundy lays out the machining marks on a torpedo tube shutter door for South Dakota, which was laid down in April.