• SEAL Delivery Vehicles are a highly specialized asset unique to US Navy SEALs.
  • US Special Operations Command and the SEALs are working on two new and improved vehicles.
  • The Mark 11 submersible and the Dry Combat submersible will round out that fleet for decades to come.
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To remain effective in an era of near-peer warfare and to counter China's growing military, US Special Operations Command and the Navy SEALs are working on two new and improved mini-submarines that are expected to enter service soon.

The two new special-operations mini-subs — the Mark 11 Shallow Water Combat Submersible and the Dry Combat Submersible — will be the backbone of Naval Special Warfare's submersible fleet for decades to come.

The Mark 11 will replace the Mark 8 Mod 1 mini-sub. The new mini-sub comes with an increased operational range and payload, more advanced sensors, improved navigation systems, and a new command-and-control structure that will allow new technologies to be introduced more efficiently.

Naval Special Warfare Navy SEAL Delivery Vehicle Mark 11
A photo of a SEAL Delivery Vehicle Mark 11, altered for security purposes, at Pearl Harbor, May 13, 2020.
US Navy/Chief Mass Comm Specialist Christopher Perez

At 23 feet long, the Mark 11 will be able to carry six Navy SEALs: two crew and four combat divers. The mini-sub will be to dive to about 165 feet and will be flooded while in use, meaning the SEAL operators will be exposed to the elements and will have to use dry suits and oxygen tanks. (The British Special Boat Service has also ordered the Mark 11.)

SOCOM expects the Mark 11 to hit initial operating capability this summer. Should everything go according to plan, the new SEAL Delivery Vehicle will begin to phase out the Mark 8, which has been in service since the 1980s.

The Dry Combat Submersible is much larger and heavier. The 40-foot mini-submarine will have a vastly longer operational range and greater payload capacity than the Mark 11 and be more comfortable for the 10 commandos — two crew and eight combat divers — it will be able to carry.

At a recent industry conference, Cmdr. John Conway, SOCOM's program manager for special-operations forces undersea systems, likened the Dry Combat Submersible to "an electric truck" that can do a lot of things at the same time and can be adapted and improved with new sensors and systems in response to future threats and operational environments.

Naval Special Warfare Navy SEAL Delivery Vehicle Mark 11
A photo of a SEAL Delivery Vehicle Mark 11, altered for security purposes, at Pearl Harbor, May 13, 2020.
US Navy/Chief Mass Comm Specialist Christopher Perez

Naval Special Warfare is also looking at "other nontraditional ways to launch" the Mark 11, such as "a containerized solution" off of "some vessel of opportunity or things like that," Navy Cmdr. James Hanlon, SOCOM's program manager for special-operations maritime systems, said at the conference, according to Defense News.

In addition to the new Mark 11 and Dry Combat Submersible, Naval Special Warfare is working on a service-life extension program for the Dry Deck Shelter, which is attached to a submarine's hull and allows SEALs and other combat divers to exit and enter the submarine while underway.

The Navy's six Dry Deck Shelters were built between 1982 and 1991 and were expected to have service lives of 40 years. The planned extension would allow them to operate until the 2050s

The Navy SEAL team's secret

Navy Los Angeles-class submarine USS Dallas dry deck shelter
US Navy submarine USS Dallas with a dry deck shelter attached, July 19, 2004.
US Navy/Paul Farley

The Navy SEAL teams are most well known for their direct-action capabilities. High-profile operations over the last 20 years, including the raid that killed Osama bin Laden, have fostered a belief that all that SEALs do is kick down doors and go after bad guys.

But SEAL teams have other capabilities and are proficient in many skill sets. The SEAL Delivery Vehicles are perhaps one of their most exotic capabilities, and the two SEAL Delivery Vehicle teams specialize in three mission sets: underwater insertion and extraction of special operations troops, underwater special reconnaissance, and underwater special operations.

In addition, SEAL Delivery Vehicle teams can support maritime counterterrorism operations by stealthily moving special operators close to a target that is in or near the water.

Generally, SEAL operators avoid an assignment to a SEAL Delivery Vehicle team because of the extremely difficult mission set. Although all Navy SEALs are combat divers, SEAL Delivery Vehicle team members take combat diving to the next level. Eight- to 10-hour dives are not uncommon.

Naval Special Warfare Command, which oversees the SEALs, has two delivery vehicle teams, which were first stood up in the early 1980s.

Navy SEAL Delivery Vehicle
A SEAL Delivery Vehicle being loaded onto USS Dallas in Norfolk, Virginia, February 6, 2006.
US Navy/Chief Journalist Dave Fliesen

SEAL Delivery Vehicle Team One, now based in Hawaii, is dedicated to the West Coast and operations in the Pacific. SEAL Delivery Vehicle Team Two was deactivated in 2008 but reestablished in 2019 amid the shift toward great-power competition. SDVT-2 is based in Little Creek, Virginia, and is the dedicated delivery vehicle unit for the East Coast and operations in Europe.

The delivery vehicle teams are now part of Naval Special Warfare Group 8, which was created in 2020 through the consolidation of two other special warfare groups. The officer who led the group with the delivery vehicle teams was selected to lead Group 8 when it was formed, suggesting SDVs will have an important role going forward.

SEAL Delivery Vehicles are SOCOM's only special-operations submersible capability. In a conflict with China, mini-subs paired with the Navy's attack submarines would be ideal for getting SEALs into tough spots and denied areas, which will be essential for countering China's anti-access/area-denial umbrella over the Western Pacific.

"Our relationship with our submarine force has never been closer," Rear Adm. Hugh Howard III, commander of Naval Special Warfare Command, told senators in May. "We see the undersea as absolutely critical to deterrence. I think that it is a place that we maintain advantage, and it is a place where we must maintain advantage to critically deter our peer adversaries."