Editing SEAL Delivery Vehicle (section)

==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}}]]