
A wet sub is a type of underwater vehicle, either a
submarine
A submarine (often shortened to sub) is a watercraft capable of independent operation underwater. (It differs from a submersible, which has more limited underwater capability.) The term "submarine" is also sometimes used historically or infor ...
or a
submersible
A submersible is an underwater vehicle which needs to be transported and supported by a larger ship, watercraft or dock, platform. This distinguishes submersibles from submarines, which are self-supporting and capable of prolonged independent ope ...
, that does not provide a dry environment for its occupants. It is also described as an underwater vehicle where occupants are exposed to ambient environment during operations. The watercraft is classified as medium-sized or small vessel. This type of submarine differs from other underwater personal transport devices by the fact that it has a hull around it and it is not a "bare bones" design.
Usually,
scuba diver
Scuba, originally SCUBA, often expanded to scuba set, is any self contained underwater breathing apparatus, a source of breathing gas used for underwater diving which is carried by the diver.
Scuba may also refer to:
* Scuba diving
Scuba ...
s ride outside the device as one would ride a
motorcycle
A motorcycle (motorbike, bike; uni (if one-wheeled); trike (if three-wheeled); quad (if four-wheeled)) is a lightweight private 1-to-2 passenger personal motor vehicle Steering, steered by a Motorcycle handlebar, handlebar from a saddle-style ...
or in a semi-enclosed opening like a
kayak
]
A kayak is a small, narrow human-powered watercraft typically propelled by means of a long, double-bladed paddle. The word ''kayak'' originates from the Inuktitut word '' qajaq'' (). In British English, the kayak is also considered to be ...
or
bobsled
Bobsleigh or bobsled is a winter sport in which teams of 2 to 4 athletes make timed speed runs down narrow, twisting, banked, iced tracks in a gravity-powered sleigh. International bobsleigh competitions are governed by the International Bobs ...
, although it can be designed to fully enclose its occupant(s) to reduce drag. An enclosed vehicle may also provide a dry viewing chamber for the occupant(s). The sub is generally propelled by an electric motor and is battery powered. The depth and endurance is typically limited by the requirements of the divers, particularly water temperature and breathable air.
Military use

Wet subs have been used to transport and deploy
special operations
Special operations or special ops are military activities conducted, according to NATO, by "specially designated, organized, selected, trained, and equipped forces using unconventional techniques and modes of employment." Special operations ma ...
forces in waters too shallow for an ordinary submarine, lay mines (particularly for attaching
limpet mine
A limpet mine is a type of naval mine attached to a target by magnets. It is so named because of its superficial similarity to the shape of the limpet, a type of sea snail that clings tightly to rocks or other hard surfaces.
A swimmer or diver m ...
s directly to a ship), firing
torpedo
A modern torpedo is an underwater ranged weapon launched above or below the water surface, self-propelled towards a target, with an explosive warhead designed to detonate either on contact with or in proximity to the target. Historically, such ...
es, or gathering intelligence in harbors. They have also been used to plant listening and recording devices on undersea cables in
Operation Ivy Bells.
[Introduction to Naval Special Warfare](_blank)
For military use, the operator will sometimes use a
rebreather
A rebreather is a breathing apparatus that absorbs the carbon dioxide of a user's exhaled breath to permit the rebreathing (recycling) of the substantial unused oxygen content, and unused inert content when present, of each breath. Oxygen is a ...
device so as not to leave a trail of bubbles. Military wet subs are deployed from a larger submarine or from a surface ship. The
SEAL Delivery Vehicle
The SEAL Delivery Vehicle (SDV) is a crewed submersible and a type of swimmer delivery vehicle used to deliver United States Navy SEALs and their equipment for special operations missions. It is operated by SEAL Delivery Vehicle Teams.
The SDV, ...
(SDV) used by the
United States Navy SEALs
The United States Navy Sea, Air, and Land (SEAL) Teams, commonly known as Navy SEALs, are the United States Navy's primary special operations force and a component of the United States Naval Special Warfare Command. Among the SEALs' main func ...
and
British Special Boat Service
The Special Boat Service (SBS) is the special forces unit of the United Kingdom's Royal Navy. The SBS can trace its origins back to the Second World War when the Army Special Boat Section was formed in 1940. After the Second World War, the Roy ...
is an example that is in use today. The SDV is used to insert Navy SEALs in shallow coastal waters or attack surface ships.
The
Motorised Submersible Canoe
The Motorised Submersible Canoe (MSC), nicknamed Sleeping Beauty, was an underwater vehicle built by the British Special Operations Executive (SOE) during the Second World War. It was designed to enable a single frogman to sabotage enemy ships, ...
, developed by the British
Special Operations Executive
Special Operations Executive (SOE) was a British organisation formed in 1940 to conduct espionage, sabotage and reconnaissance in German-occupied Europe and to aid local Resistance during World War II, resistance movements during World War II. ...
during
World War II
World War II or the Second World War (1 September 1939 – 2 September 1945) was a World war, global conflict between two coalitions: the Allies of World War II, Allies and the Axis powers. World War II by country, Nearly all of the wo ...
, is another example.
Hobbyists
A wet sub is attractive to the amateur or small commercial builder since many of the problems associated with a dry sub are avoided as only the propulsion and power systems need to be waterproof and life support is much less of an issue than it is with a sealed occupant chamber. Complete submarines of this type are also available commercially.
Wet sub designs are often used for human-powered submarines because they are smaller and lighter than dry submarines. An example is the pedal-operated wet-sub called "the Scubster", which is powered by a twin propeller connected to the pedal belt.
Research

Every two years, a human-powered submarine race takes place at the Naval Surface Warfare Center in
Bethesda, Maryland
Bethesda () is an unincorporated, census-designated place in southern Montgomery County, Maryland, United States. Located just northwest of Washington, D.C., it is a major business and government center of the Washington metropolitan region ...
.
See also
Military wetsubs
*
SEAL Delivery Vehicle
The SEAL Delivery Vehicle (SDV) is a crewed submersible and a type of swimmer delivery vehicle used to deliver United States Navy SEALs and their equipment for special operations missions. It is operated by SEAL Delivery Vehicle Teams.
The SDV, ...
*
Human torpedo
Human torpedoes or manned torpedoes are a type of diver propulsion vehicle on which the diver rides, generally in a seated position behind a fairing. They were used as secret naval weapons in World War II. The basic concept is still in use.
...
Commercial wetsubs
*
Necker Nymph
The ''Necker Nymph'' is a submersible vehicle operated by Virgin Aquatic from the 32-metre yacht '' Necker Belle'', which is based at the Virgin Limited Edition resort Necker Island in the British Virgin Islands.
The ''Necker Nymph'' is the ...
*
Diver propulsion vehicle
A diver propulsion vehicle (DPV), also known as an underwater propulsion vehicle, sea scooter, underwater scooter, or swimmer delivery vehicle (SDV) by armed forces, is an item of diving equipment used by scuba divers to increase range underwa ...
*
Scubster
Custom wetsubs
*
Wet Nellie
"Wet Nellie" is the behind-the-scenes name given to a custom-built submarine, created for the 1977 ''James Bond'' film '' The Spy Who Loved Me'' in the shape of a Lotus Esprit S1 sports car. The Esprit was chosen to give James Bond a glamorous c ...
References
External links
{{DEFAULTSORT:Wet Sub