Editing SEAL Delivery Vehicle

{{Short description|Manned wet submersible for deploying naval special forces}}
{|{{Infobox ship begin <!-- submarine classes -->
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|Ship image=US Navy 050505-N-3093M-007 Members of SEAL Delivery Vehicle Team Two (SDVT-2) prepare to launch one of the team's SEAL Delivery Vehicles (SDV) from the back of the Los Angeles-class attack submarine USS Philadelphia (SSN 690).jpg
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|Ship caption=SEAL Delivery Vehicle Team Two launch an SDV from [[Los Angeles-class submarine|''Los Angeles''-class]] submarine {{USS|Philadelphia|SSN-690|6}}
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{{Infobox ship class overview
|Builders=[[The Columbia Group]]<ref>{{cite press release |title=Dual Use Submersible Vehicle Wins Prestigious R&D 100 Award for Battelle, The Columbia Group, and Bluefin Robotics |url=http://www.marketwired.com/press-release/dual-use-submersible-vehicle-wins-prestigious-r-d-100-award-battelle-the-columbia-group-1809899.htm |last=Delaney |first=Katy |access-date=20 September 2018 |publisher=Battelle |via=MarketWired |date=July 10, 2013}}</ref>
|Operators=[[United States Navy]]
|Class before=
|Class after=''[[Shallow Water Combat Submersible]] (planned)''<ref name=George />
|Subclasses=
|Built range=
|In commission range=Since 1983<ref name=George>{{Cite magazine| issn = 1059-1028| last = George| first = Alexander| title = Climb Into the Mini-Sub Navy SEALs Use to Bring Death From Below| magazine = Wired| access-date = 2018-09-04| date = 2014-08-01| url = https://www.wired.com/2014/08/navy-seal-submarine/}}</ref>
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{{Infobox ship characteristics
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|Header caption=
|Ship type=[[Submersible]], [[diver propulsion vehicle]]
|Ship displacement=17 tons (15.4&nbsp;tonnes)<ref name="Jane's">{{cite book|title=Jane's Fighting Ships|year=2010}}</ref>
|Ship length={{convert|6.7|meter|ft}}<ref name=Kelly98 />
|Ship beam={{convert|1.8|meter|ft}}<ref name="Jane's" />
|Ship draught=
|Ship draft=
|Ship propulsion=[[Silver-zinc batteries]] powering an electric motor and single screw propeller<ref name=Museum /><ref name=Kelly98 />
|Ship speed=* {{convert|6|kn|km/h|abbr=on}} (top speed)<ref name="Jane's" />
* {{convert|4|kn|km/h|abbr=on}} (cruising speed)<ref name=Kelly98 />
|Ship range=* {{convert|15|to|18|nmi|km|abbr=on}} with diving team<ref name="Jane's" />
* {{convert|36|nmi|km|abbr=on}} without<ref name=Kelly98>{{cite report |last=Kelly |first=Christopher J. |date=April 1998 |title=The Submarine Force in Joint Operations |url=https://fas.org/man/dod-101/sys/ship/docs/98-145.pdf |publisher=Air Command and Staff College |location=[[Maxwell Air Force Base, Alabama]] |docket=AU/ACSC/145/1998-04 |access-date=7 September 2018 }}</ref>
|Ship endurance=8<ref name=Kelly /> to 12 hours<ref name=Davis />
|Ship test depth={{convert|6|meter|ft}}<ref name="SDV">{{cite magazine|url=http://www.thefreelibrary.com/By+sea+%26+stealth%3A+maritime+special+forces+tend+to+arrive+in+hostile...-a0140709845 | last=Hooton| first=E. R. | magazine=Armada International |title=By sea & stealth: maritime special forces tend to arrive in hostile territory by sea and by stealth, but where once they would be delivered by rubber dinghies from a submarine now they are using Special Delivery Vehicles (SDV) and even midget submarines. |access-date=September 4, 2018 |date=December 1, 2005}}</ref>
|Ship complement=6 (2 crew, 4 passengers)<ref name=Kelly98 />
|Ship sensors=Doppler [[Inertial Navigation System]], high frequency [[sonar]] for obstacle/mine avoidance and navigation, [[GPS]]<ref name=Museum />
|Ship EW=
|Ship armament=SEAL team personal weapons, [[limpet mine]]s<ref name=Davis>{{cite web |last1=Davis |first1=Eric |title=US Navy SEALs: SDV1 |url=https://specialoperations.com/28311/us-navy-seals-sdv1/ |website=Special Operations |access-date=4 September 2018 |date=December 24, 2013}}</ref>
|Ship notes=Specifications are given for Mark 8 SDV
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The '''SEAL Delivery Vehicle''' ('''SDV''') is a crewed [[submersible]] and a type of [[diver propulsion vehicle|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, which has been in continuous service since 1983, 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 is generally deployed from the [[Dry Deck Shelter]] on a specially-modified [[Attack submarine|attack]] or [[ballistic missile submarine]]s, although it can also be launched from surface ships or land. It has seen combat in the [[Gulf War]], [[Iraq War]], and the [[OEF-HOA|US intervention in Somalia]].<ref name=Burgess>{{cite news |last1=Burgess |first1=Richard |title=New Seahorses For The Seals |work=[[Seapower (magazine)|Seapower]] |date=October 2018 }}</ref>

The SDV was intended to be replaced with the [[Advanced SEAL Delivery System]] (ASDS), a larger, dry submersible that is often confused with the SDV. The SDV is [[Wet sub|flooded]], and the swimmers ride exposed to the water, breathing from the vehicle's compressed air supply or using their own SCUBA gear, while the ASDS is dry inside and equipped with a full life support and air conditioning system. The ASDS was canceled in 2009 due to cost overruns and the loss of the prototype in a fire.<ref name=Cole>{{cite news |last1=Cole |first1=William |title=Prototype mini-sub shelved |url=http://www.dmzhawaii.org/dmz-legacy-site-two/?tag=advanced-seal-delivery-system |access-date=5 September 2018 |work=DMZ Hawai'i |date=25 July 2009 |via=[[Honolulu Star Advertiser]] |archive-date=6 September 2018 |archive-url=https://web.archive.org/web/20180906014044/http://www.dmzhawaii.org/dmz-legacy-site-two/?tag=advanced-seal-delivery-system |url-status=dead }}</ref><ref name=Polmar>{{cite web|last=Polmar |first=Norman |url=http://www.military.com/features/0,15240,181232,00.html |title=Problems Persist for SEAL Mini-Subs |publisher=Military.com |access-date=2008-12-16 |archive-url=https://web.archive.org/web/20090122063820/http://www.military.com/features/0%2C15240%2C181232%2C00.html |archive-date=22 January 2009 |url-status=live |date=16 December 2008}}</ref> The Navy currently plans to replace the SDV with the [[Shallow Water Combat Submersible]] (SWCS), which will be designated the Mark 11 SDV.<ref name=George /> The SWCS was expected to enter service in 2019.

==History==
The SDV program dates back to [[World War II]]. Initiated by the [[Office of Strategic Services]] Maritime Unit (OSS MU). A “submersible canoe” was invented by the Italians during World War I. The idea was successfully applied by the Italian Navy (''[[Regia Marina]]'') also early in World War II. The official Italian name for their craft was ''Siluro a Lenta Corsa'' (SLC or "[[Human torpedo|Slow-running torpedo]]"). The vehicle was then copied by the British when they discovered the Italian operations and called it the "[[Sleeping Beauty (canoe)|Sleeping Beauty]]" or Motorised Submersible Canoe. It was employed by OSS MU during extensive training and exercises, but was never actually deployed for combat operations.<ref>{{cite book |last1=Rees |first1=Quentin |title=The Cockleshell Canoes: British Military Canoes of World War Two' |date=2008 |publisher=Amberley Publishing |location=Stroud, Gloucestershire |isbn=978-1-84868-065-4}}</ref>

The same capability was adopted by the American [[Underwater Demolition Team]]s (UDTs) in 1947. The one-man submersible displayed little functional military potential. However, it substantiated and characterized the need for improved and expanded UDT capabilities.<ref name=Museum>{{cite web|url=https://navysealmuseum.com/home-to-artifacts-from-the-secret-world-of-naval-special-warfare/seal-delivery-vehicles-sdv-manned-submersibles-for-special-operations/|title=SEAL Delivery Vehicles|website=National Navy UDT-SEAL Museum|access-date=4 September 2018}}</ref> After the war, development continued in a garage-shop fashion by various UDT units, and included various "Marks" such as the Mark V, VI, and VII. Intermediate numbers were assigned to some vehicles that never made it off the shop floor. All were of flooded design.<ref name="nsw">[http://www.sealchallenge.navy.mil/seal/introduction.aspx Introduction to Naval Special Warfare] {{webarchive|url=https://web.archive.org/web/20080116021903/http://www.sealchallenge.navy.mil/seal/introduction.aspx |date=2008-01-16 }} ''Navy SEALs''. San Diego: [[Commander, Naval Special Warfare Command]]</ref>

The first SDV to be operationally deployed was the Mark VII, which entered service in June 1972 after being tested between 1967 and 1972.<ref name=Museum /> It could carry three SEALs plus a pilot sitting in compartments fore and aft. It had a hull made from fiberglass and non-ferrous metals to hinder detection and was powered by a [[silver-zinc battery]] attached to an electric motor.<ref name=Museum /> The Mark VIII SDV, the model that is still in use today, began to supplant the Mark VII starting in 1983.<ref name=Museum />

The wet vehicle SDV program (officially named the Swimmer Delivery Vehicle, later re-designated the SEAL Delivery Vehicle after the Swimmer Delivery Vehicle Teams were renamed [[SEAL Delivery Vehicle Teams]]) currently centers on the Mark VIII Mod 1. The SDV was first developed in 1975 for use among UDT/SEAL teams. The early Mark 8 Mod 0 SDVs had a PRC104 [[UHF]] radio for use underwater. The newer model Mark 8 Mod 1 has a dual sliding canopy and quick release hatch.<ref name="nsw" />
[[File:Sdv-2.jpg|thumb|A Seal Delivery Vehicle maneuvers into a drydeck on the submarine {{USS|Kamehameha|SSN-642|6}}]]

==Design==
SDVs carry a pilot, co-pilot, and four person 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 is [[silver-zinc battery]] powered and equipped with propulsion, navigation, communication, and life-support equipment.<ref name=Museum /> The batteries directly power the electric motor that drives the single screw propeller.<ref name=Museum /> Because they are all electric, SDVs are extremely difficult to detect using passive sonar, and their small size makes them hard to detect using other means.<ref name=Kelly /> The Mark 8 Mod 1 SDV can deliver four fully equipped SEALs to the mission area, be "parked" or loiter in the area, retrieve the SEALs, and then return to the launch site. The SEALs sit upright in the Mark 8, with the pilot and co-pilot/navigator facing forward and the other four facing aft.<ref name=Kelly /> For air, the SEALs rely on their own [[Diving cylinder|air tank]]s or [[rebreather]]s, supplemented by compressed air tanks on the SDV. The crew and passenger compartment in the Mark 8 is small, cramped, and pitch black except for the dim lights of the instrument panel;<ref name=Thompson /> SEALs describe riding in an SDV as like "being locked in a little black coffin deep under the water."<ref name=Kelly /> A 2011 article reported that out of 2,600 SEALS roughly 230 are trained to operate the SDVs. <ref name="Thompson" />

SDVs are generally launched from a [[Dry Deck Shelter]] on the back of a [[submarine]], although they can also be deployed from [[Amphibious assault ship|amphibious carrier]]s and other surface ships equipped to launch and recover the SDV. SDVs are launched and recovered by surface ships using a crane.<ref name=Kelly /> They can also be [[airdrop]]ped (uncrewed) into an operational area from a [[C-130 Hercules]] airplane.<ref name=GS>{{cite web|url=http://www.globalsecurity.org/military/systems/ship/sdv.htm|title=SEAL Delivery Vehicle [SDV]|first=John|last=Pike|website=Global Security |access-date=4 September 2018}}</ref> Finally, the SDV can be launched from the shore.<ref name=Kelly98 />

An SDV can be launched from one platform and recovered by another. {{USS|John Marshall|SSBN-611|6}} demonstrated this capability during a multilateral exercise in the [[Mediterranean]] when it recovered and then launched another country's SDV.<ref name=Kelly98 />

===Mark 8 SDV===
The Mark 8 Mod 1 SDV is the only SDV officially in use by the US Navy and Royal Navy. It is an upgrade of the earlier Mark 8 Mod 0 SDV. The Mod 1 is quieter, faster, more efficient, and has a longer range than the Mod 0.<ref name=Klose /> Its updated electronics, materials, and battery and motor systems gives it twice the range and 1.5 times the speed of the Mod 0.<ref name=Klose>{{cite journal |last1=Klose |first1=John |title=SDV Units in Great Demand as Speed, Range Improve |journal=Seapower |date=July 2003 |url=http://www.navyleague.org/sea_power/jul_03_24.php |access-date=5 September 2018 |archive-date=6 September 2018 |archive-url=https://web.archive.org/web/20180906052703/http://www.navyleague.org/sea_power/jul_03_24.php |url-status=dead }}</ref> Another advantage of the Mark 8 Mod 1 over its predecessor is that it is built from aluminium instead of plastic reinforced fiberglass, making its hull sturdier and roomier.<ref name=Klose /> The sturdier hull means that it can be deployed from [[CH-46 Sea Knight]] and [[CH-53E Super Stallion]] helicopters, although SDVs often break or explode when dropped in the water from a helicopter, making aerial deployments impractical and undesirable.<ref name=Kelly />

The Mark 8 Mod 1 SDV has an endurance of about eight to 12 hours,<ref name=Davis /> giving it a range of {{convert|15|to|18|nmi|km|abbr=on}} with a diving team or {{convert|36|nmi|km|abbr=on}} without.<ref name="Jane's" /> The main limiting factor on endurance is not batteries or breathing gas for the SEALs, but water temperature:<ref name=Williams /> humans can only spend so much time in cold water, even with [[wetsuit]]s, before their blood pressure drops and they become dehydrated from losing blood volume and body fluids, respectively.<ref name=Kelly />
[[File:SDVmk9 SWA-Deck-Crew.jpg|thumb|left|US Navy SEALs deploy a torpedo-armed Mark 9 SDV from a submarine]]

===Mark 9 SDV===
Despite being a development of the Mark 8 SDV, the Mark 9 is a very different vehicle, designed for attacking surface ships rather than deploying SEAL teams on clandestine operations. Indeed, the Mark 9 and Mark 8 share very few common parts.<ref name=Klose /> The Mark 9 carries two SEALs, a pilot and a navigator, and two [[Mark 31 torpedo|Mark 31]] or [[Mark 37 torpedo]]es for standoff attacks against ships.<ref name=Williams>{{Cite book| publisher = Naval Institute Press| isbn = 9781612510064| last = Williams| first = Gary| title = SEAL of Honor: Operation Red Wings and the Life of LT. Michael P. Murphy (USN)| date = 2010-12-07| url=https://books.google.com/books?id=e8DnFCKgxzYC&pg=PA101| page=101}}</ref> These torpedoes can travel up to {{convert|3|nmi|km}} in a straight line,<ref name=Kelly98 /> carry a {{convert|330|lb|kg|adj=on}} warhead, and are capable of sinking ships as large as [[cruisers]].<ref name=Sutton>{{cite web |last1=Sutton |first1=H.I. |title=SDV Mk9: US Navy SEAL's torpedo armed mini-sub |url=http://www.hisutton.com/SDV%20Mk9.html |website=Covert Shores |access-date=20 September 2018 |date=21 August 2016}}</ref> In addition to torpedoes, the Mark 9 also carried [[limpet mine]]s and satchel charges in a large cargo compartment aft of the pilot and co-pilot.<ref name=Museum />

The Mark 9 is designed to clandestinely approach enemy vessels while submerged, surface to fire torpedoes, and then escape unnoticed. As such, its design incorporates [[Stealth technology|stealth]] characteristics, including a lower profile and sonar absorbing materials.<ref name=WalshWalker>{{Cite book| publisher = Simon and Schuster| isbn = 9780671868536| last1 = Walsh| first1 = Michael J.| last2 = Walker| first2 = Greg| title = SEAL!: From Vietnam's PHOENIX Program to Central America's Drug Wars : Twenty-six Years with a Special Operations Warrior| date = 1994| url=https://books.google.com/books?id=gMgxIvUz104C&pg=PA43}}</ref> The Mark 9 SDV was intended to attack ships in shallow coastal waters that full-size submarines could not enter,<ref name=Museum /> and to draw attention of an enemy fleet away from the Mark 9's parent submarine.<ref name=Sutton /> Though it proved very effective in exercises, the Mark 9 was retired starting in 1989 and was fully phased out of service by the mid-1990s due to manpower and budget constraints and because all of its capabilities save launching torpedoes were duplicated by the Mark 8.<ref name=Museum />

The pilot and navigator operate the vehicle from a prone position and lay side by side. The prone position gave the Mark 9 a low profile and enabled it to operate in very shallow water,<ref name=Kelly>{{Cite book| publisher = Open Road Media| isbn = 9781504047456| last = Kelly| first = Orr| title = Special Ops: Four Accounts of the Military's Elite Forces| date = 8 August 2017| url=https://books.google.com/books?id=rTotDwAAQBAJ&pg=PT123}}</ref> although SEALs reported that staying prone for the entire duration of an operation was uncomfortable.<ref name=Sutton />

The Mark 9's sleek profile and independent [[diving planes]] enabled it to be especially agile.<ref name=Sutton /> It was also faster than the Mark 8, reaching speeds of {{convert|7|-|9|kn|kph}}, owing to its twin [[screw propeller]]s and high-performance [[silver-zinc batteries]].<ref name=Museum /> Its speed and agility led operators to compare it to flying a fighter jet or driving a sports car.<ref name=Kelly />

[[File:US Navy 060206-N-1464F-003 A SEAL Delivery Vehicle (SDV) is loaded aboard the Los Angeles-class fast attack submarine USS Dallas (SSN 700) in preparation for a Special Warfare Training exercise.jpg|thumb|A Mark 8 SDV is loaded aboard ''Los Angeles''-class submarine {{USS|Dallas|SSN-700|6}}]]

==Operational history==
The SDV is used primarily for inserting SEALs for covert operations or for placing mines on ships. It is also used for underwater mapping and terrain exploration, location and recovery of lost or downed objects, and reconnaissance missions.<ref name=CGSC>{{cite book |title=SOF Reference Manual |date=1999 |publisher=[[Army Command and General Staff College]] |location=[[Fort Leavenworth, Kansas]] |url=https://fas.org/irp/agency/dod/socom/sof-ref-2-1/index.html |chapter=US Naval Special Operations Forces}}</ref> It has been invaluable at deploying SEAL teams in clandestine missions, as it has enabled them to land on shores inaccessible to a larger submarine with a degree of stealth greater than that offered by small surface craft, helicopters, or other means.<ref name=Thompson>{{cite magazine |last1=Thompson |first1=Kalee |last2=Weinberger |first2=Sharon |last3=Pappalardo |first3=Joe |title=Secrets of the Navy SEALs |url=https://www.popularmechanics.com/military/weapons/a6849/secrets-of-the-navy-seals/ |access-date=19 September 2018 |magazine=Popular Mechanics |date=1 August 2011}}</ref> In exercises, the SDV has been found to excel at anti-shipping attacks, being able to attack targets in heavily-guarded fleets or docked at military bases and then slip away undetected.<ref>{{Cite book| edition = First | publisher = Phoca Press, LLC| isbn = 9780990915300| last = Hawkins| first = Tom| others = Lisa Merriam (ed.)| title = America's Hidden Heroes: The History and Evolution of U.S. Navy Frogmen and SEALs| location = New York, NY| date = 2015-02-06}}</ref> Additionally, it can carry larger [[limpet mine]]s than those carried by a diver and has a much greater range than a diver, enabling attacks on larger and more distant enemy ships.<ref name=Kelly /> However, the SDV is not without its weaknesses, namely its range, reliability, and mobility. The SDV's short range, which is contingent on [[sea state]], water temperature, payload, and other factors, sometimes hinders operations. In one example, the Navy wanted to use an SDV to get a closer look at a Soviet ship anchored in a [[Cuba]]n harbor {{convert|18|mile|km}} upriver from the [[Caribbean Sea]]. The SDV could not have made the round trip to the Soviet vessel from an American ship outside of Cuba's territorial waters, so the mission had to be called off.<ref name=Kelly />

Mark 8 SDVs saw combat during the [[Gulf War|First Gulf War]], where they performed mine reconnaissance and demolition missions.<ref name=Museum /><ref name=George /> In the [[Iraq War]], Mark 8 SDVs were used to secure offshore oil and gas terminals.<ref name=George /> Several days before the beginning of the [[2003 invasion of Iraq]], two SDV teams were launched from [[Mark V Special Operations Craft]] in the Persian Gulf. Their objectives were the [[Hydrographic survey|hydrographic reconnaissance]] of the [[KAAOT|Al Basrah (MABOT) and Khawr Al Amaya (KAAOT) Oil Terminals]]. After swimming under the terminals and securing their Mark 8 Mod 1s, the SDV SEALs spent several hours taking pictures and surveying Iraqi activity on both platforms before returning to their boats.<ref>{{cite book |title=The Mammoth Book of Inside the Elite Forces |first=Nigel |last=Cawthorne |author-link=Nigel Cawthorne |year=2008 |location=London, UK |publisher=Robinson |isbn=978-1-84529-821-0 |url-access=registration |url=https://archive.org/details/unset0000unse_l5i5 }}</ref> On March 20, 2003, SEALs from [[SEAL Team 8]] and [[SEAL Team 10|10]] (31 SEALs, 2 [[United States Navy Explosive Ordnance Disposal|Navy EOD]], 1 USAF combat controller, and several Iraqi interpreters) moved to seize the MABOT oil terminal and KAAOT Oil Terminals, in part using SDVs. The terminals were quickly seized with no casualties, and explosives which were found on the terminals were made safe by Polish [[GROM]] operators.<ref>{{cite book |title=Special Forces in the War on Terror |first=Leigh |last=Neville |year=2015 |location=[[Oxford]], UK |publisher=[[Osprey Publishing]] |isbn=978-1-47280-790-8 |page=123}}</ref>

In 2003, SEALs using SEAL Delivery Vehicles swam ashore along the [[Somalia|Somali]] coastline and emplaced covert surveillance cameras. Known as cardinals, the cameras were designed to watch likely target locations for wanted terrorists as [[al-Qaeda]] and its affiliates began to regroup in the country, however the cameras only took one image a day and captured very little.{{sfnp|Neville|2015|pp=282-284}}

In American service, the SDV is deployed with [[SEAL Delivery Vehicle Team 1]] (SDVT-1), based in [[Pearl Harbor]], and [[SEAL Delivery Vehicle Team 2]] (SDVT-2), based in [[Little Creek, Virginia]]. SDVT-1 operates on behalf of [[CENTCOM|Central Command]] and [[USPACOM|Pacific Command]] in the Middle East and Indian and Pacific Oceans. SDVT-2 operates in the Atlantic and [[European Command]] and [[SOUTHCOM|Southern Command]], and is primarily focused on supporting the activities of the [[Sixth Fleet]].<ref name=CGSC />

The SDV suffered from reliability concerns early in its lifespan. [[Lieutenant commander|LCDR]] Doug Lowe, a member of [[SDV Team 1]] in the 1980s, reported that his team's SDVs were operational less than 50 percent of the time.<ref name=Kelly /> However, reliability improved with usage: LCDR Lowe later commanded [[SDV Team 2]] in the 1990s and reported that his subs were ready more than 90 percent of the time.<ref name=Kelly />

The main failure of the SDV is its poor mobility.<ref name=Kelly /> The SDV can only be effectively deployed from specially modified submarines and surface ships. Although it can be transported by [[C-130]] airplanes, the relative scarcity of vessels capable of deploying an SDV limits its usage.<ref name=GS /> Submarines are the preferred means of deployment, as enemies can see a surface ship deploying an SDV with a crane, further limiting the SDV's mobility and usage. Modifying a surface ship to launch and recover the SDV through an underwater door, like the Italian Navy had done for its [[human torpedo]]es in WWII, would have helped alleviate this problem.<ref name=Kelly />

The [[Special Boat Service]] of the [[United Kingdom Special Forces]] operates three Mark 8 Mod 1 vehicles.<ref name="UK">{{Cite journal |last=Dorschner |first=Jim |date=27 May 2009 |title=Special Delivery |journal=Jane's Defence Weekly |volume=46 |issue=21 |page=28}}</ref><ref>{{Cite web |last1=J. Valaik |first1=Daniel |last2=E. Hyde |first2=Dale |last3=F. Schrot |first3=John |last4=R. Thomas |first4=John |date=November 1997 |title=Thermal Protection and Diver Performance in Special Operations Forces Combat Swimmers (Resting Diver Phase) |url=https://apps.dtic.mil/sti/pdfs/ADA384687.pdf |archive-url=https://web.archive.org/web/20220721185546/https://apps.dtic.mil/sti/pdfs/ADA384687.pdf |archive-date=2022-07-21 |website=Defense Technical Information Center |publisher=Naval Medical Research Institute |pages=100}}</ref>

==Operators==
;{{USA}}
*[[United States Navy]]: [[Navy SEALs]]
**[[SEAL Delivery Vehicle Team 1]] (SDVT-1)
**[[SEAL Delivery Vehicle Team 2]] (SDVT-2)
;{{GBR}}
*[[Royal Navy]]: [[Special Boat Service]]

==Gallery==

<gallery widths="225px" heights="165px" class="center">
File:SEAL Delivery Team operations.jpg|A Navy diver and special operator from SEAL Delivery Team 2 operate an SDV from the nuclear-powered guided-missile submarine {{USS|Florida|SSGN-728}}
File:SEAL Delivery Vehicle loading.jpg|An SDV being loaded aboard ''Los Angeles''-class attack submarine {{USS|Dallas|SSN-700|6}}
File:SDVmk9 LittleBoPeep.jpg|Mark 9 SDV "Little Bo Peep" armed with a LAM-5 mine
File:US Navy 050505-N-3093M-003 A member of SEAL Delivery Vehicle Team Two (SDVT-2) prepares to launch one of the team's SEAL Delivery Vehicles (SDV) from the back of the Los Angeles-class attack submarine USS Philadelphia (SSN 690).jpg|A member of SEAL Delivery Vehicle Team Two (SDVT-2) prepares to launch a Mark 8 SDV from ''Los Angeles''-class attack submarine {{USS|Philadelphia|SSN 690|6}}
</gallery>

==See also==
* [[Chariot manned torpedo]]
* [[Human torpedo]]

==References==
{{Reflist}}

==External links==
{{Commons category|SEAL Delivery Vehicle}}
* [https://thenewsrep.com/48683/watch-seal-delivery-vehicle-team-strike/ Video of a SEAL Delivery Vehicle in use]
* [https://www.military.com/equipment/mark-viii-seal-delivery-vehicle Military.com article]
* [http://ussnautilus.org/blog/swimmer-delivery-vehicles/ USS ''Nautilus'' Museum exhibit]

{{Underwater diving|divequ}}

{{DEFAULTSORT:Seal Delivery Vehicle}}
[[Category:Submarines of the United States Navy]]
[[Category:United States Navy SEALs]]
[[Category:Wet subs]]
[[Category:Midget submarines]]