The
SEAL Delivery Vehicle or (SDV) is a manned
submersible***Also see Submersible drilling rig for offshore drillingA submersible is a commerical or non-military midget submarine with limited service range and is typically transported to its area of operation by a surface vessel or large submarine....
and a type of
Swimmer Delivery VehicleSwimmer Delivery Vehicles are midget submersibles designed to transport combat swimmers from a combat swimmer unit or naval Special Forces underwater, over long distances. SDVs carry a pilot, co-pilot, and combat swimmer team and their equipment, to and from maritime mission objectives on land or...
used to deliver
United States Navy SEALsThe United States Navy Sea, Air, and Land Forces, commonly known as the Navy SEALs, are the Special Operations Forces of the United States Navy, employed in direct action and special reconnaissance operations...
and their equipment for
special operationsSpecial operations are military operations that are considered "special" .Special operations are typically performed independently or in conjunction with conventional military operations. The primary goal is to achieve a political or military objective where a conventional force requirement does...
missions.
SDVs carry a pilot, co-pilot, and combat swimmer team and their equipment to and from maritime mission objectives on land or at sea. The pilot and co-pilot are often a part of the fighting team. The SDV has compressed air to extend the range of a swimmer's own
air tankA diving cylinder, scuba tank or diving tank is used to store and transport high pressure breathing gas as a component of SCUBA . It provides gas to the SCUBA diver through the demand valve of a diving regulator.Diving cylinders typically have an internal volume of between and a maximum pressure...
or
rebreatherA rebreather is a type of breathing set that provides a breathing gas containing oxygen and recycled exhaled gas. This recycling reduces the volume of breathing gas used, making a rebreather lighter and more compact than an open-circuit breathing set for the same duration in environments where...
.
The SDV is used primarily for covert or clandestine missions to denied access areas (either held by hostile forces or where military activity would draw notice and objection).
It should not be confused with the larger, dry submersible called the
Advanced SEAL Delivery SystemAdvanced SEAL Delivery System was a midget submarine operated by the United States Navy and United States Special Operations Command that is designed to provide stealthy submerged transportation for special operations forces from the decks of nuclear submarines for primary use as an insertion...
(ASDS).
The
SEAL Delivery Vehicle or (SDV) is a manned
submersible***Also see Submersible drilling rig for offshore drillingA submersible is a commerical or non-military midget submarine with limited service range and is typically transported to its area of operation by a surface vessel or large submarine....
and a type of
Swimmer Delivery VehicleSwimmer Delivery Vehicles are midget submersibles designed to transport combat swimmers from a combat swimmer unit or naval Special Forces underwater, over long distances. SDVs carry a pilot, co-pilot, and combat swimmer team and their equipment, to and from maritime mission objectives on land or...
used to deliver
United States Navy SEALsThe United States Navy Sea, Air, and Land Forces, commonly known as the Navy SEALs, are the Special Operations Forces of the United States Navy, employed in direct action and special reconnaissance operations...
and their equipment for
special operationsSpecial operations are military operations that are considered "special" .Special operations are typically performed independently or in conjunction with conventional military operations. The primary goal is to achieve a political or military objective where a conventional force requirement does...
missions.
SDVs carry a pilot, co-pilot, and combat swimmer team and their equipment to and from maritime mission objectives on land or at sea. The pilot and co-pilot are often a part of the fighting team. The SDV has compressed air to extend the range of a swimmer's own
air tankA diving cylinder, scuba tank or diving tank is used to store and transport high pressure breathing gas as a component of SCUBA . It provides gas to the SCUBA diver through the demand valve of a diving regulator.Diving cylinders typically have an internal volume of between and a maximum pressure...
or
rebreatherA rebreather is a type of breathing set that provides a breathing gas containing oxygen and recycled exhaled gas. This recycling reduces the volume of breathing gas used, making a rebreather lighter and more compact than an open-circuit breathing set for the same duration in environments where...
.
The SDV is used primarily for covert or clandestine missions to denied access areas (either held by hostile forces or where military activity would draw notice and objection).
It should not be confused with the larger, dry submersible called the
Advanced SEAL Delivery SystemAdvanced SEAL Delivery System was a midget submarine operated by the United States Navy and United States Special Operations Command that is designed to provide stealthy submerged transportation for special operations forces from the decks of nuclear submarines for primary use as an insertion...
(ASDS). The SDV is
floodedA wet sub is a type of underwater vehicle that does not provide a dry environment for its occupants. Usually, wet suited scuba divers will ride upon the device , although it can be designed to fully enclose its occupant to provide lower drag...
, and the swimmers ride exposed to the water, breathing from the vehicle's compressed air supply or using their own SCUBA gear. (The ASDS is dry inside, with a full life support and air conditioning system.)
The SDV is lithium-ion battery powered and equipped with propulsion, navigation, communication, and life-support equipment. The Mk 8 Mod 1 SDV can deliver several fully equipped SEALs to the mission area, be "parked" or loiter in the area, retrieve the SEALs, and return home.
The Mark 8 Mod 1 SDV is currently the only SDV employed by US military. Other operational vehicles included the now retired MK 6, MK 7, and the Mk 11. The
Special Boat ServiceThe Special Boat Service or SBS is the special forces unit of the British Naval Service. Their motto is "By Strength and Guile". It forms part of the United Kingdom Special Forces group....
of the
BritishThe United Kingdom of Great Britain and Northern Ireland is a sovereign state located off the northwestern coast of continental Europe. It is an island country, spanning an archipelago including Great Britain, the northeastern part of Ireland, and many small islands...
Royal MarinesThe Royal Marines are the marine corps and amphibious infantry of the United Kingdom and, along with the Royal Navy and Royal Fleet Auxiliary, form the Naval Service. They are also the United Kingdom's specialists in amphibious warfare, including the operation of landing craft; mountain warfare;...
operates three Mk8 Mod 1 vehicles.
SDVs are generally launched from a
Dry Deck ShelterA Dry Deck Shelter is a removable module that can be attached to a submarine to allow divers easy exit and entrance while the boat is submerged...
on the back of a
submarineA submarine is a watercraft capable of independent operation below the surface of the water. It differs from a submersible, which has only limited underwater capability...
, or from amphibious carriers (surface craft) equipped to launch and recover the SDV. It can also be
airdropAn airdrop is a type of airlift, developed during World War II to resupply otherwise inaccessible troops, who themselves may have been airborne forces. In some cases, it is used to refer to the airborne assault itself. Early airdrops were conducted by pushing small crates with parachutes out of the...
ped (unmanned) into an operational area from a
C-130 HerculesThe Lockheed C-130 Hercules is a four-engine turboprop military transport aircraft built by Lockheed. Capable of takeoffs and landings from unprepared runways, the C-130 was originally designed as a troop, medical evacuation, and cargo transport aircraft...
.
History
The SDV program dates back to
World War IIWorld War II, or the Second World War , was a global military conflict which involved a majority of the world's nations, including all great powers, organized into two opposing military alliances: the Allies and the Axis...
, when various sleds and vehicles developed for use by the
Underwater Demolition TeamUnderwater Demolition Teams were a precursor to the current United States Navy SEALs. The UDTs conducted beach and hydrographic reconnaissance, explosive cable and net cutting, explosive destruction of underwater obstacles to enable major amphibious landings, limpet mine attacks, submarine...
s. After the war development continued in a garage-shop fashion by various UDT units, and included various "Marks" as the MK V, VII, VII, and XII. Intermediate numbers were assigned to some vehicles that never made it off the shop floor. All were of flooded design.
The wet vehicle SDV program (officially named the Swimmer Delivery Vehicle, sometimes erroneously designated as the SEAL Delivery Vehicle after the Swimmer Delivery Vehicle Teams were renamed SEAL Delivery Vehicle Teams) currently centers on the MK VIII MOD 1, was first established in 1975 for use among UDT/SEAL teams. The early MK8 MOD 0 SDVs had a PRC104 UHF
ultra high frequencyUltra high frequency designates a range of electromagnetic waves with frequencies between 300 MHz and 3 GHz . Also known as the decimetre band or decimetre wave as the wavelengths range from one to ten decimetres...
radio for use underway. The newer model MK8 MOD1 has a dual sliding canopy and quick release hatch.
See also
- Swimmer Delivery Vehicle
Swimmer Delivery Vehicles are midget submersibles designed to transport combat swimmers from a combat swimmer unit or naval Special Forces underwater, over long distances. SDVs carry a pilot, co-pilot, and combat swimmer team and their equipment, to and from maritime mission objectives on land or...
- Advanced SEAL Delivery System
Advanced SEAL Delivery System was a midget submarine operated by the United States Navy and United States Special Operations Command that is designed to provide stealthy submerged transportation for special operations forces from the decks of nuclear submarines for primary use as an insertion...
- United States Navy SEALs
The United States Navy Sea, Air, and Land Forces, commonly known as the Navy SEALs, are the Special Operations Forces of the United States Navy, employed in direct action and special reconnaissance operations...