Submarines rank among the most advanced and intricate machines ever built, engineered to function for extended periods beneath the ocean while remaining largely undetected. Within their reinforced hulls, crew members navigate narrow corridors and live without sunlight, completely cut off from the natural cycles of life on the surface.
Daily life on board is highly regimented, shaped by rotating watch duties, shared berthing, and strict routines that leave little room for privacy or personal comfort. Even so, strong bonds frequently form among submariners. The demands of prolonged isolation, cramped conditions, and constant operational risk require endurance and absolute reliance on one another, fostering a distinctive sense of unity among those who serve in the ocean’s silent depths.
Overview of how submarines have developed over the years
Nuclear-powered submarines integrate nuclear storehouses, launch platforms and weaponry to present an elusive and formidable package. Before the New Strategic Arms Reduction Treaty (START), the US Navy's 14 Ohio-class ballistic missile submarines were armed with 24 submarine-launched ballistic missiles, each carrying multiple warheads. As per the treaty, each is now limited to a maximum of 20.
Typically, submarines embark on 77-day sea patrols, equipped with a 90-day food supply, before returning to port for just over a month. The Navy's ballistic missile submarines operate with two alternating crews - Blue and Gold - maximizing their operational efficiency and minimizing the number of vessels deployed.
The inaugural combat submarine, designed during the American Revolution, was the Turtle. This roughly eight-foot spherical vessel held a single individual and was manually powered. Shortly after her development, Turtle executed the world's first submarine attack by stealthily navigating underwater, penetrating the HMS Eagle (1774) and installing explosives in her hull.
In contemporary times, submarines like the Ohio-class boast an impressive length of 560 feet and a weight exceeding 18,750 tons when submerged. The Navy's submarine fleet comprises 53 fast-attack submarines, 14 ballistic missile submarines (holding more than half of the American nuclear arsenal) and four guided-missile submarines.
Personnel stationed on these submarines undergo rigorous training, including exercises like Ice Exercise (ICEX) 2022, preparing them to navigate complex and potentially perilous environments. Such training is crucial given the uncertainties associated with serving beneath the ocean's surface.
What is downtime like inside a submarine?
Serving aboard a submarine presents challenges that are rarely encountered in other areas of military service. Like sailors assigned to surface ships, submariners live in cramped spaces with little opportunity to move freely and only a limited variety of meals. Unlike those on surface vessels, however, they spend long periods without natural sunlight, and even their exercise equipment must operate quietly to prevent revealing the submarine's position.
Despite these demanding conditions, submarine crews frequently form strong and enduring bonds. Living and working together for months in such confined spaces fosters teamwork and trust, both of which are essential for successfully completing their missions.
Life underwater also follows a carefully structured routine that differs from the schedule used aboard surface ships. Crews typically operate on a repeating cycle of three six-hour shifts: six hours on watch, six hours for personal time, and six hours of sleep. This system keeps the submarine operating around the clock while maintaining efficiency in its restricted environment.
Dealing with deadly weapons onboard the vessel
Taking care of weapons is one of the most important responsibilities for submariners. Although submarines often focus on patrol and surveillance, their missile systems are a vital part of military operations. To stay prepared, the crew must regularly check and maintain their weapons and other equipment so everything is ready to go at a moment’s notice.
The U.S. Navy plans to expand its fleet by adding up to three Virginia-class fast-attack submarines each year through 2043. Still, some experts—like former Submarine Forces Commander Vice Adm. Michael Connor—say that won’t be enough. He believes the Navy needs 66 more submarines to meet the rising need for strong underwater military power.
Looking ahead, the Navy is also working on replacing its aging Ohio-class submarines with the new Columbia-class. The first of these advanced submarines is expected to join the fleet by 2031.
Submarines play a critical role in deep-sea rescue
Submarines are not solely tools of naval warfare; they also serve as gateways to some of the ocean’s most remote and extreme environments. These sophisticated vessels enable humans to reach great depths and remain operationally prepared for emergencies occurring far below the surface.
In such scenarios, Deep-Submergence Rescue Vehicles (DSRVs) are essential assets. Though compact, these advanced U.S. Navy submersibles are engineered to dive beyond 1,000 meters, attach to disabled submarines, and extract stranded crews. They are deployed from specialized support ships known as MOSUBs, purpose-built to endure extreme underwater pressures and facilitate rapid-response rescue missions.
Similar capabilities exist in other countries as well. Nations including the United Kingdom and France maintain their own deep-sea submarine rescue systems, underscoring a shared international commitment to protecting submariners operating in some of the most dangerous environments on the planet.
Life inside a submarine means dealing with navigational challenges
Despite seeming complex, steering a submarine is relatively simple—even though the person at the helm can’t actually see where they’re going. Instead of vision, submarines depend on sonar to identify nearby objects and hazards in the water. They’re also equipped with an inertial navigation system (INS), which tracks the sub’s position by measuring its motion over time.
Because GPS and radio waves don’t penetrate water, the INS plays a crucial role in navigation while helping the submarine remain undetectable to adversaries. This high-tech system uses gyroscopes and accelerometers to determine speed and direction.
One of the most iconic pieces of submarine equipment is the periscope. This tall, narrow instrument allows the crew to observe the surface while staying hidden beneath the waves. Some models can extend as high as 60 feet!
Has much has changed over the years?
When comparing older submarines to their modern counterparts, it's striking how similar they are, especially when looking at those used during World War I and II. Though these early subs were slower and couldn't stay submerged for as long as today's vessels, they still played a crucial role in reconnaissance and providing support at sea.
The most significant leap in submarine technology came after the war with the introduction of nuclear-powered submarines in 1954. Unlike their diesel-powered predecessors, these nuclear submarines marked the dawn of a new era. Their ability to remain submerged indefinitely, thanks to nuclear power, made them the first true submarines in terms of endurance and operational capabilities.