How the Navy SEALs Work

The SEAL acronym stands for Sea, Air and Land, which identifies the elements in which they operate. SEALs work in small units, and sometimes in a platoon of up to 16. They are trained to perform specific tasks under any type of circumstance and in any environment. Their training takes place in water, and in extreme hot and cold environments.

SEAL missions require detailed planning and precise execution. SEALs are trained to perform missions that fall into five main categories:

When SEALs aren't deployed, they're in constant training, both to hone basic skills and to learn new skills and techniques that will make a difference when they are deployed.

The above categories overlap when it comes to actual missions, but these are the basis of SEAL training: to be expert in the skills required to perform these various tasks.

In 1941, after the Japanese bombed Pearl Harbor, U.S. troops were forced to invade Japanese territory by sea, often facing landmines and attacks from unseen enemies. As a countermeasure to these hazards, the U.S. Navy began creating teams that were specially trained to go safely ashore and clear the path of obstacles and other hazards and return intelligence on enemy locations. These teams were called Naval Combat Demolition Units. Their training was heavy in physical strengthening and included carrying heavy loads, swimming, running and maneuvering in small boats. Their training also included handling explosives. Eventually, they evolved into Underwater Demolition Teams (UDTs).

The UDTs were organized in 1943. Also known as frogmen, they were responsible during the Korean War for swimming to shore before an invasion and blowing up obstacles in their path, clearing the way for the amphibious U.S. invasion. They also destroyed important targets like bridges and tunnels.

In the 1960s, the Soviet Union's ally, North Vietnam, was fighting against a U.S. ally, South Vietnam. President Kennedy wanted to send in small teams of guerrilla fighters to help South Vietnam. With the Army's Green Beret unit already set up, it was time for the Navy to create its own Special Operations unit. Building on the training of the UDTs, the Navy SEALs (an acronym for Sea, Air and Land) were created. Their training readied them for the work ahead in the jungles, coasts and rivers of Vietnam. Their task was to go behind enemy lines and raid enemy camps, sabotage supplies, cut off enemy communications and destroy stored ammunitions. They were very successful in their missions.

With the Vietnam War ending without victory, many cuts were made in military spending, and the number of special forces units was in many cases cut in half. The success of the SEALs in Vietnam, however, proved their value.

See the SEALs Virtual Museum for more background information.

Hooyah! — the war cry of the Navy SEALs — becomes an automatic response for SEALs during the torturous SEAL training. While there may be other variations in meaning, "hooyah" generally means "yes," "understood," and "I'm not letting this evolution get the best of me." (Evolution is the term used for each event in the training schedule.)

SEAL training is brutal. It takes over 30 months to train a Navy SEAL to the point at which they will be ready for deployment. The SEALs who emerge are ready to handle pretty much any task they could be called on to perform, including diving, combat swimming, navigation, demolitions, weapons and parachuting. The training pushes them to the limit both mentally and physically in order to weed out those who may not be able to successfully complete the demanding missions and operations with which SEALs are faced. The types of stresses they endure during BUD/S (Basic Underwater Demolition/SEAL) are the same stresses they will endure as SEALs. If they can't withstand it when lives aren't on the line, chances are good they won't be able to withstand it when lives are at stake.

From day one in SEAL training, trainees are taught the importance of teamwork. Focus is not on the individual. The fact that the SEALs have never left another SEAL behind on a mission is a testament to this belief system. Throughout their training, they learn more and more why teamwork is necessary in the type of work they will soon be entering: SEALs are performing tasks that may not be possible for a single man to accomplish but can be possible for a team composed of men who have the same training and skills. Their success depends on what they can do together as a team.

Entering training to become a Navy SEAL is voluntary. Anyone can volunteer, and officers and enlisted servicepeople train side by side. (Women are now allowed to join but as of 2021, none have successfully finished SEAL training.) In order to enter SEAL training, however, they do have to meet certain requirements. Those wishing to volunteer for SEAL training have to:

Pass a stringent physical screening test that includes the following:

These are just the minimum requirements. The better you can perform on these tests, the more likely you are to be accepted as a SEAL.

Once a potential SEAL qualifies for training, the real fun starts.

Now that you've passed the physical screening test, it's time for Basic Underwater Demolition/SEAL (BUD/S). This begins with a two-month training period at Naval Special Warfare Preparatory School in Great Lakes, Illinois.

Prep School ends with a modified physical screening test, by which time candidates have to be able to:

Basic Underwater Demolition/SEAL (BUD/S) training is divided into several phases:

There is also the infamous Hell Week, which takes place toward the end of basic conditioning, which is the toughest training in the U.S. military. Hell Week is 5-1/2 days of difficult training on fewer than four hours of sleep. It's held in the first phase of BUD/S training, before the Navy makes an investment in SEAL operational training. More on Hell Week later in this article.

BUD/S lasts six months. The initial orientation comprises three weeks of learning the expectations and ways of Navy SEALs. More important, it is a time to prepare physically and mentally for what's ahead.

Once orientation is complete, the remaining time is broken down into seven weeks of basic conditioning, seven weeks of combat diving and seven weeks of land-warfare training. The training takes place at the Naval Amphibious Base at Coronado, California.

Basic conditioning is when the going gets rough. This is the phase where most Drops on Request (what civilians would call "quitting") happen. For seven weeks, trainees' days are filled with running, swimming, calisthenics, learning small-boat operations and building teamwork. Performance is measured by a 2-mile (3.2-kilometer) ocean swim, 4-mile (6.4 kilometer) run and an obstacle course. A trainee's time for these exercises must continuously improve.

Another important part of basic conditioning is drown-proofing. In this evolution, trainees must learn to swim with both their hands and their feet bound. To pass drown-proofing, trainees enter a 9-foot (2.7- kilometer) deep pool and complete the following steps with their hands and feet tied:

Another evolution is surf torture, also called "cold water conditioning." The water temperatures usually hover around 65 degrees Fahrenheit (18 C), and never go above 68 degrees F (20 C). From there, trainees may be ordered to do some calisthenics or run a mile and a half (2.4 kilometers) down the beach in their wet clothes and boots. Then, they're ordered back into the surf. Many drills also require that teams carry their rubber boats over their heads as they run from one task to another.

The fourth week of basic conditioning is known as Hell Week. This is when students train for five-and-a-half days with a maximum total of four hours of sleep. Hell Week begins at midnight Sunday and ends Friday afternoon. During this time, trainees face continuous training evolutions. During Hell Week, trainees get four meals a day — sometimes MREs, but usually hot meals of unlimited quantities. Eating hot food is a substitute for being warm and dry. It gives a needed psychological boost to tired trainees, many of whom are nearly sleeping while they eat.

Pretty much every evolution during Hell Week involves the team (or boat crew) carrying their IBS— inflatable boat, small — over their heads. Timed exercises, runs, and crawling through mud flats are interspersed throughout the five-and-a-half days. Only about 25 percent of SEAL candidates make it through Hell Week. This extreme training is critical, though. SEALs on missions must be able to operate efficiently, oblivious to subzero temperatures and their own physical comfort. Their lives, as well as the lives of others, may depend on it.

Listening closely to orders is another critical element of training during BUD/S, particularly during Hell Week when brains are getting fuzzy from lack of sleep. The instructor may purposely leave out part of an order to see who is really listening. For example, during a series of orders requiring trainee teams to do exercises using a 300-pound (136-kilogram) log, he may leave out mention of the log for one order. Team leaders who are paying attention will catch this, and their team gets a small break in the difficulty of the task by performing it without having to carry the log. The instructor might reward the team by allowing it to stand by the fire and rest or sit and sleep for a few minutes.

If a candidate can't take it anymore, all they have to do is approach a bell that's been erected on the training ground and ring it. Ringing the bell signifies defeat and they're out. SEAL candidates might feel the worst part of Hell Week is physical but the mental part is just as important. As NavySEALs.com puts it, "While instructors could get anyone to quit if they wanted to, that's not what they're after. They apply great physical and mental stress, sow the seeds of doubt, and give tempting invitations for trainees to quit. It's up to the individual student to either turn it into increased resolve or decide on his own to quit. The majority of the students who make it through Hell Week go on to graduate BUD/S and become SEALs."

Combat Diving

Since much of a SEAL's work is done underwater, SCUBA (self-contained underwater breathing apparatus) and combat diving are top priorities for training.

SEALs train extensively for seven weeks to become combat swimmers and learn open and closed-circuit diving.

Land Warfare

During land-warfare training, SEALs train for seven weeks in basic weapons, demolitions, land navigation, patrolling, rappelling, marksmanship and small-unit tactics. They are also trained to react to sniper attacks and to use "edged" weapons such as knives and other blades. SEALs must be able to drive any vehicle and be skilled in high-speed and evasive driving techniques. Hand-to-hand combat is also taught during this phase of training.

To be prepared for anything, they are taught the tactics small units must use, including handling explosives, infiltrating enemy lines, recovery (snatch-and-grab) techniques, and proper handling of prisoners. SEALs must also be able to survive in extreme environments and provide medical treatment (field medicine).

When BUD/S training is over, those remaining move on to basic parachute training at the Army Airborne School at Fort Benning, Georgia.

This training lasts for three weeks and is followed by two weeks of Special Operations Technician Training at the Naval Special Warfare Center in Coronado, California. Here's where trainees learn about diving medicine and medical skills called Special Operations Medical Sergeant Course (18-D). This is a 30-week course on burns, gunshot wounds and trauma.

It is after successful completion of the 18-D that trainees are given their Naval Enlisted Code (NEC). They now either serve the remainder of their first enlistment (two-and-a-half to three years) in a SEAL delivery vehicle team (SDV) or SEAL team.

Further training is provided in Special Reconnaissance and Direct Action, where SEALs learn more about completing tasks such as:

SEAL Assignments and Deployment

New SEALs report immediately to their operational units and begin 18 months of pre-deployment training, which includes extensive individual-, platoon-, and squadron-level training in preparation for deployment with their SEAL platoon. This training/deployment cycle is repeated to make sure SEALs are constantly improving and learning new skills that can save lives and help missions succeed.

In the following sections, we'll take a look at some examples of SEAL missions.

While we may hear about some amazing SEAL missions, most of what they do is off the radar. The few missions that do make the evening news, however, show us just how hard — and how important — the SEALs' jobs are.

Counterterrorism

On Jan. 6, 2002, during Operation Enduring Freedom (2001-2003), SEALs were sent to the landlocked country of Afghanistan in search of Osama bin Laden and other terrorists hiding in the caves of Zawar Kili. What was supposed to be a 12-hour mission turned into an eight-day mission.

SEALs and other SOCOM (Special Operations Command) operators searched more than 70 caves over a 3-mile- (4.8-kilometer-) long ravine near the Pakistani border. Their search turned up caches of weapons, ammunition, supplies and a wealth of intelligence information. They survived the unexpectedly extended mission on supplies they found in the al-Qaeda camps.

According to Naval Special Warfare Command:

In the book "Warrior Soul: The Memoir of a Navy SEAL", former SEAL Chuck Pfarrer describes how a mission to protect a U.S. Navy amphibious ship (at an undisclosed location) turned into the capture of would-be terrorists. As leader of his SEAL detachment, Pfarrer was responsible for securing the ship in port while its cargo of ammunition was unloaded.

After searching many fishing boats in the vicinity of the harbor, Pfarrer noticed a fishing boat coming into the area that didn't look like the others. He became suspicious and jumped into a Zodiac boat with two other SEALs, intending to search the slowly approaching boat. Maneuvering to prevent the boat from having access to the ship, they turned to face the boat head-on in order to force it to stop. Confirming their suspicions, the boat began increasing its speed.

The Zodiac was running side by side with the fishing boat, and Pfarrer was yelling "Halt!" — but the boat's driver wouldn't stop. As the Zodiac got closer, one of the men in the boat began reaching under a fishing net for what looked like an AK-47. The Zodiac driver sharply turned and rammed the Zodiac into the fishing boat. Pfarrer pulled out his gun to fire a warning shot across the hull of the boat, but his gun jammed. He jumped into the fishing boat with the men, followed by the other two SEALs.

After a brief struggle, they tied up the men on the fishing boat. Looking beneath the nets, they found two large bundles of Yugoslavian-made TNT taped together with fuses ready, along with two AK-47s. Explosives of this type are designed to punch holes in a ship's steel hull. The men in the fishing boat were combat swimmers preparing to attach these explosives to the anchored U.S. Navy ship.

During the Persian Gulf War (aka Operation Desert Storm, 1991), after a month of air attacks against Iraq, Allied forces were ready to move into Iraq-occupied Kuwait and begin the ground war. With 17,000 Marines in ships off the coast of Kuwait City, the Foxtrot platoon from SEAL Team One had the mission of creating a diversion. The plan was to make the Iraqis believe that Allied forces were planning an amphibious attack.

In the dark of night, the SEAL team approached the Kuwaiti shore in landing boats, stopping about 500 yards (457 meters) out and swimming the rest of the way in. Each SEAL towed a 20-pound (9-kilogram) case of explosives. Right under enemy noses, they planted the explosives on the Kuwaiti coast and swam back to their boats. The explosives were set to go off at 1 a.m.

As the land explosives went off, the SEALs fired automatic weapons and launched grenades, creating a huge amount of noise that caught the attention of the Iraqis. The noise, combined with the force of Marines seen off the coast, convinced the Iraqis that the attack was coming from the sea. They pulled two divisions from the front line and moved them to the coast, only to find the SEALs and the Marine diversion gone. The ground war began against a much weakened and vulnerable Iraqi force.

One of the most known recent Navy SEAL missions is the 2011 killing of Osama bin Laden called Operation Neptune Spear. On May 2, 2011, 24 SEALs flew in on two helicopters to bin Laden's compound in Abbottabad, Pakistan and killed him. The entire operation lasted 40 minutes, with SEAL Team Six credited for the mission. Osama bin Laden's body was taken and buried at sea within 24 hours to comply with Islamic law.

In 2012, A team of SEALs rescued American aid workers Jessica Buchanan and Poul Thisted, who were kidnapped in late 2011 by men in north-central Somalia. The two were working for a nongovernmental organization called the Danish Relief Council when they were taken. On Jan. 25, SEALs parachuted down, killed all nine kidnappers and saved Buchanan and Thisted.

In 2017, a Navy SEAL team rescued American citizen Philip Walton who had been abducted by a criminal gang in Nigeria.

Like professionals in any other field, SEALs can only successfully do their jobs if they have the right tools. Their weapons, vehicles and other gear can help them not only perform their missions, but also come out of those missions alive.

Clothing

It isn't uncommon for SEALs to need clothing for varying temperatures and tasks. For example, when swimming to shore for a mission, the SEAL may need gear for extremely cold water temperatures as well as warmer land temperatures. For cold weather, clothing must prevent heat loss resulting from all sources, including radiation and evaporation. The SEAL must often generate heat through physical activity, and then vent it if they move into a warmer location or begin to overheat due to extreme of exertion. Layering and ventilation allow for cooling and help keep perspiration from making clothing damp.

Weapons

SEALs use firearms such as the FN SCAR (Special Operations Forces Combat Assault Rifle), SCAR-L and SCAR H with pistols carried as backup. They also use the FN SCAR as a sniper rifles such as the designated marksman rifle SSR and a personal defense weapon SCAR PDW. The FN SCAR was designed in Belgium and manufactured in the U.S.

SEALs also use the M4A1, which is a high-tech, multiple-use assault rifle. This AR is used in close quarters battle and counterterrorist operations. The M4A1 can also be converted to a grenade launcher or shotgun. Machine guns like the MK46 and MK48 are also used.

Each vehicle that Navy SEALs use to transport teams and units to their destination has a specific benefit and utility.

One type of vehicle is the SEAL Delivery Vehicle. These are vehicles that operate below the surface of the water to deliver Navy SEALs and their equipment to their mission area. The crew uses underwater breathing apparatus for life support while navigating the submerged SDV to the destination. Remaining completely submerged the entire time, some models of SDVs can deliver several SEALs with their gear to their mission area, remain in the area while they complete the mission, and then return them to their ship.

There are several primary surface watercraft. We list them below.

The MK V Special Operations Craft (SOC) is the most versatile, high-performance combatant craft in the Naval Special Warfare inventory. It is used primarily in medium-range ocean transport of SEAL combat swimmers in environments where the threat is low-to-medium. It is also used for some coastal patrol and maritime interdiction operations, such as destroying an enemy supply line. The MK V can operate from shore facilities or from specially equipped ships.

The NSW Rigid-hull Inflatable Boat (RHIB) is an 36-foot (11-meter) high-speed, high-buoyancy, extreme-weather craft used for moving SEAL tactical elements to and from the ship and beaches. It is large enough to transport an entire SEAL squad.

The Special Operations Craft-Riverine (SOC-R) performs short-range insertion and extractions. It is used in river environments and has a top speed of 40 knots. It holds up to 20,500 pounds (9,300 kilograms) of personnel and cargo and is well-suited to inland waterways. The SOC-R can be transported by U.S. Air Force cargo aircraft and by helicopter.

The Combat Rubber Raiding Craft (CRRC) is a 15-foot (4.5-meter), heavily reinforced, inflatable rubber boat that is useful on many missions. This is the one trainees are carrying overhead during BUD/S training (it's often called a Zodiac — Zodiac manufactures the CRRC). In deployment, it is used for over-the-horizon transportation and dropping and retrieving lightly armed SEALS on beaches and in rivers.

SCUBA

Open-circuit System: An open-circuit system is the typical breathing system, where the diver breathes air from a supply tank and the exhaled air is released into the water.

Closed-circuit Oxygen Systems: With this type of system, the diver breaths 100-percent oxygen, and his exhaled breath is recirculated within the apparatus, where it is filtered and turned back into breathable air. This system is useful for working in shallow water.

Oxygen time is reduced as the water gets colder. For diving in extremely cold water, SEALs must wear dry suits and a specially adapted version of the LAR V Draeger rebreather — a larger oxygen canister allows the diver to breathe underwater for a longer period.

Closed-circuit Mixed Gas System

This system is similar to the closed-circuit oxygen system described above, but the oxygen is mixed with air to maintain a certain "partial pressure of oxygen" (PPO2) level. This increases the depth to which a SEAL can dive and the length of time he can stay there.

When SEALs arrive from the air, they are often going to extremely difficult-to-reach places. In this case, they may jump from a plane into the ocean with their Zodiac, parachute into the area, or use fast-rope and rappelling techniques.

When parachuting, SEALs use either static-line or free-fall techniques. Free-fall techniques include High Altitude/Low Opening (HALO) jumps and the more difficult High Altitude/High Opening (HAHO) jumps. High-altitude jumping requires oxygen and special equipment to ensure that the chute opens in the event the jumper blacks out, which is not that uncommon for high-altitude jumps. Goggles can shatter from the cold, and eyes can freeze shut, making the fall even more interesting. A device called an FF2 will automatically activate the jumper's rip cord if the chute hasn't opened at a preset altitude. The Special Insertion/Extraction rig is needed for mountain-top extractions.

HAHO jumps, where chutes are deployed just a few seconds after the jump and SEALs form a "stack" to stay together, keep the SEALs in a tight group when they land. This is a difficult maneuver that requires a lot of training as a team. The lowest man in the formation uses a compass and landmarks to steer them to their destination.

Fast-rope and rappelling techniques require helicopters to drop SEALs by way of a rope to their location. Fast roping is a drop technique whereby a 50-to-90-foot (15-to-27-meter) rope is dropped from the helicopter, and SEALs slide down the rope using a Swiss seat harness. To brake, they apply their hands in a towel-wringing motion — using their feet to brake would damage the rope. This video gives an example of how that looks.

Once SEALs are on the ground, their equipment, like their clothing, must suit the particular environment to blend in. Mountain-climbing gear, snowshoes, land-navigation equipment and the right vehicles are all critical to their success.

Camouflage netting for desert environments where there is little-to-no natural concealment can keep SEALs from becoming an enemy target. Dust goggles keep them from being blinded by flying sand, and CamelBak water packs allow them to drink while still having use of their hands.

Operations in jungle or wooded areas necessitate machetes to clear dense foliage as well as special netting and hammocks to ward off potentially lethal insect bites.

For all types of environments, SEALs carry a GPS and weapons.

Naval Special Warfare is comprised of SEAL teams, SEAL Delivery Vehicle Teams and Special Boat Teams that are all deployed worldwide for a variety of operations.

Teams and Platoons

There are eight SEAL teams. Each team eight operational platoons and a headquarters element. SEAL platoons consist of 16 SEALs — two officers and 14 enlisted men. A platoon is generally the largest operational element assigned to a mission. The platoon may also be divided into two squads or four elements. Every member of a SEAL platoon is qualified in diving, parachuting and demolitions.

The teams are split between the East Coast and West Coast of the United States. The odd-numbered teams fall under the command of Naval Special Warfare Group One and are based on the West Coast in Coronada, California The even-numbered teams are under the command of Naval Special Warfare Group Two and are based on the East Coast in Little Creek, Virginia.

SDV Teams and NSW Units

There are other specialized teams of SEALs called SEAL Delivery Vehicle teams (SDVT). SDV teams operate in areas where it is too far out for a SEAL to swim and carry gear. Using underwater SDV watercraft, these teams increase the areas in which SEALs can operate. SDV teams usually deploy from submarines, but can also deploy from shore-based stations or surface ships.

There are two SDV teams. SEAL Delivery Vehicle Team 1 (SDVT-1) is based in Pearl Harbor, Hawaii, and operates in the Pacific and Central geographic areas. SEAL Delivery Vehicle Team 2 (SDVT-2) is based at Little Creek, Virginia, and conducts operations throughout the Atlantic, Southern and European areas.

There are also Naval Special Warfare Command based in locations around the world. These units have several responsibilities, including acting as training commands for SEALs and planning, coordinating and supporting the activities of SEAL platoons.

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