Shallow Water Combat Submersible

Class overview
BuildersTeledyne Brown Engineering
OperatorsUnited States Navy
Royal Navy (planned)
Preceded bySEAL Delivery Vehicle
Cost$383 million (program cost)
On order7 USN, 3 RN
Building2
Completed2
General characteristics
TypeSubmersible, diver propulsion vehicle
Displacement4.5 tonnes (5.0 short tons)
Length6.8 meters (22 ft)
Beam1.5 meters (4.9 ft)
Draft1.5 meters (4.9 ft)
PropulsionLithium-ion batteries powering electric motors
Speed6 kn (11 km/h)
Endurance12 hours
Test depth>190 feet (58 m)
Complement6 (2 crew, 4 passengers)
Sensors &
processing systems
Inertial navigation system, high-frequency sonar for obstacle/mine avoidance and navigation, GPS
ArmamentSEAL team personal weapons, limpet mines

The Shallow Water Combat Submersible (SWCS), also known as the Mark 11 SEAL Delivery Vehicle (SDV Mk 11), is a crewed, wet (free-flooding) submersible that serves as a swimmer delivery vehicle for special-operations missions by United States Navy SEALs. Designed to replace the Mark 8 SEAL Delivery Vehicle (SDV Mk 8) on a 1-to-1 basis, Teledyne was awarded a contract to deliver 10 units for a cost of $179 million. The first two ships were delivered in 2018, with the last units planned for delivery in 2022. The SWCS will serve alongside the pressurized Dry Combat Submersible (DCS), a midget submarine developed by Lockheed Martin to replace the cancelled Advanced SEAL Delivery System (ASDS).