Ohio-class submarine

The Ohio class is a group of big boats.

They live deep under the sea. There are 18 boats in this group. Most of them carry big missiles.

Some boats carry many small missiles. They can also carry special sailors. These boats are very quiet in the water. They help keep the country safe. They stay at sea for many days.

These big boats are very important.

The Ohio class is a group of large submarines.

These boats are the largest ever built for the U.S. Navy. There are 18 boats in the group. Fourteen are ballistic missile submarines, called SSBNs. These boats carry big missiles to help keep the country safe.

Four boats are cruise missile submarines, called SSGNs. These four boats can carry up to 154 Tomahawk missiles. They can also carry 66 special sailors for missions.

Most of these boats are named after U.S. states. They are very quiet under the water. This helps them stay hidden. Each boat has two crews. One is the Blue crew. The other is the Gold crew. They take turns working on the boat. Each patrol lasts about 70 days. One boat once stayed at sea for 140 days. This was the longest patrol ever. The Navy will slowly replace these boats starting in 2031.

The Ohio-class submarines are a special group of large vessels.

They are the largest submarines ever built for the U.S. Navy. There are 18 boats in this entire class. Fourteen of them are ballistic missile submarines, or SSBNs. These boats carry large missiles to help keep the country safe.

The other four are cruise missile submarines, known as SSGNs. These SSGNs can carry up to 154 Tomahawk cruise missiles. They can also carry 66 special operations sailors for different missions.

These submarines work by staying hidden deep under the ocean. They are designed to be very quiet while they move. This quietness helps them stay hard to find.

Each boat uses two different crews to keep working. One is called the Blue crew and the other is the Gold crew. They take turns serving on the boat during long trips. Most patrols last about 70 days at a time. One boat, the USS Pennsylvania, once stayed at sea for 140 days. This was the longest patrol ever recorded for these boats.

Engineers began designing these boats in the 1970s. They wanted a way to carry the new Trident missiles. The first eight boats were built to use Trident I missiles. Later, the ninth boat and others used the larger Trident II missiles.

These newer missiles are much more accurate. They also carry more power than the older versions. The Navy even worked to upgrade older boats to use these better missiles. This big project was finished by the middle of 2008.

Building these huge boats is a very big job. The sections of the hull were made at a facility in Rhode Island. After they were made, the parts were moved to Connecticut. There, workers assembled the sections into a complete submarine. Most of the boats have names of U.S. states. This is a tradition that used to be for battleships. The boats are very heavy, weighing 18,750 tons when they are underwater.

You can think of these submarines like a silent, floating base. Just as a base stays ready for a mission, these boats stay ready at sea. They use special radio links to talk to leaders on land. These links use very low frequency systems to work through the water. This allows leaders in Nebraska to send targets to the missiles quickly. The Navy will slowly start to replace these boats in 2031. New boats will eventually take over their important jobs.

The Ohio-class submarine is a massive group of nuclear-powered vessels used by the United States Navy. These submarines are the largest ever built for the U.S. Navy. There are 18 submarines in this class in total. Fourteen of them are ballistic missile submarines, which are called SSBNs. The other four are cruise missile submarines, known as SSGNs.

These boats are vital for the United States' nuclear-deterrent triad. This triad includes strategic bombers, intercontinental ballistic missiles, and these sea-based submarines. They help maintain national security by providing a powerful presence under the ocean.

Each Ohio-class boat displaces 18,750 tons when submerged. The SSBNs are designed to carry large missiles for long-range deterrents. They can carry 24 Trident II ballistic missiles. Alternatively, they can carry 22 tubes that each hold seven BGM-109 Tomahawk cruise missiles. The SSGN versions have even more capacity for conventional weapons. An SSGN can carry up to 154 Tomahawk cruise missiles. They can also carry a complement of Harpoon missiles through their torpedo tubes.

This huge amount of weaponry makes them very versatile.

To keep the submarines working constantly, the Navy uses a unique crew system. Each submarine is assigned two complete crews, called the Blue crew and the Gold crew. These crews take turns serving on the boat during long missions. A typical deterrent patrol lasts between 70 and 90 days. One submarine, the USS Pennsylvania, set a record with a 140-day patrol.

To help with the change between crews, the boats have three large logistics hatches. These hatches allow for the rapid transfer of supply pallets and machinery. This design helps speed up replenishment and maintenance while in port.

Stealth is a very important feature for these submarines. They are designed to be extremely quiet while they move through the water. During sea trials in 1982, the USS Ohio was reported to be virtually undetectable. They are estimated to be as quiet at cruising speeds of 20 knots or more as previous submarine classes. This quietness allows them to operate as a clandestine presence. To receive instructions, they use secure and constant radio communications links. These systems use very low frequency signals to reach the boats deep underwater. This allows the United States Strategic Command in Nebraska to send targets quickly.

The history of the class began with designs in the 1970s. Engineers wanted to create a boat that could carry the new Trident missile. The first eight submarines were originally armed with Trident I C4 missiles. Starting with the ninth submarine, the USS Ohio, the boats used the larger Trident II D5 missile. The Trident II is more accurate and carries 12 reentry vehicles. This is more destructive power than the eight vehicles carried by the Trident I. Between 2000 and 2008, the Navy converted the older boats to carry these newer missiles.

In 1994, a study called the Nuclear Posture Review changed how the fleet was used. The Navy decided that 14 SSBNs were enough for strategic needs. They chose to convert the four oldest boats into SSGNs. These four boats were the USS Ohio, Michigan, Florida, and Georgia. The conversion process cost about $1 billion per vessel in 2008 dollars. These SSGNs can also carry up to 66 special operations personnel, such as Navy SEALs. They use swimmer lockout chambers to allow these sailors to exit the boat.

Building these massive vessels is a complex industrial process. The submarine hulls are constructed from large sections. Each four-deck section has a specific diameter. These sections were first produced at the General Dynamics Electric Boat facility in Rhode Island. After production, they were moved to a shipyard in Groton, Connecticut, for final assembly. Most of the submarines are named after U.S. states. This follows a tradition once reserved for battleships and cruisers. The Ohio-class will eventually be replaced by new submarines starting in 2031.