Headline Specifications

The DDU is the next evolutionary step in surface-subsurface watercraft, combining exceptional surface performance with a transitional submersion mechanism and outstanding subsurface manoeuvrability, speed and range.

A specification document developed against an internal User Requirement Document (URD) has been created cross-referencing the craft at the Technology Demonstration level, through Prototype and on to Low Rate Initial Production (LRIP).

There is no formal design freeze until the in-house URD is mapped against a System Requirements Document or URD from the customer.


Length Overall 10.75 m
Length Moulded 10.4 m
Beam Overall 3.2 m
Draught –
Full Fuel and 2 crew 0.64 m
Height (excluding aerials) 2.3m
Crew (pilot & navigator) 2
Swimmers 6


Displacement – Dry 8,500 kg
Full Load Displacement 10,800 kg
Maximum Hoisting Weight 10,800 kg
Fuel Tank (fitted) 400 l (2 x 200 l)
Speed 30/40 knots
Full Load Condition (sea state dependent)
Endurance 250 nm (expandable)
Engine Yanmar 8LV-370Z
Gearbox ZF 220 (with neutral position)
Waterjet Rolls Royce Kamewa FF310


Dive Depth 50 m
Endurance (expandable) 24 nm
Cruise Speed (opps) 4 kn
Sprint Speed 8 kn
Range 25 nm
Battery Power 120 kWh
Battery Type Li-ion (NMC)
Thrusters 8 x 20 kW
Transition Dive Time 260 seconds
4.5min (to MDD)