DG2 SDV

Technical Specification FW051-01

THE INVISIBLE ENEMYThe DG2 EN type SDV is designed to transport two combat divers and its offensive equipment from the operational base (such as a ship or submarine) to the target (such as a ship moored/anchored, a harbour or coastal installation) and to transport them back to the base once the mission is complete. The DG2 EN is a highly effective insidious and stealthy warfare submersible craft designed for sabotage and intelligence missions. The great support given by the SDV to the combat swimmers is evident in terms of speed, endurance, comfort and carried volume. Furthermore, just like the glorious MAIALI employed by the Italian Navy during World War II, the DG2 ENs are characterized by simplicity of construction and operation, great reliability and a limited need of maintenance.Today, these characteristics have been considerably enhanced further, thanks to our recent technological innovations and developments - the result of our specialized expertise and advanced research, as well as our commitment to satisfy the ever more demanding requirements of today’s navies.The DG2 ENs have an operating radius of 40 nautical miles; consequently they must be taken to within that distance of their targets by a carrier such as a submarine, a surface ship, or even a fishing boat. Clearly, the submarine is the best solution because it safeguards the stealth of the craft much more effectively - this being the most important aspect of a covert mission. The DG2 EN SDV can be transported on the deck of a DG160 class submarine, with apposite connections, to a navigational depth of up to 100 metres. Alternatively, a suitable interface can be developed with another type of submarine. Whilst the fundamental design principles of the DG2 EN are still classic, a number of important technological innovations have been introduced.

The key features of the DG2 EN are:• New, high-tech Control Module with a fully integrated Navigation System• Use of new generation underwater sensors• New technology for long endurance battery pack

MAIN CHARACTERISTIC DATA• Overall length 7.56 metres• Hull diameter 0.80 metres• Maximum width 0.80 metres• Maximum height 1.30 metres• Displacement ready to dive 2.40 tons• Weight in air 2.34 tons• Maximum operating depth 50 msw• Maximum transit depth 100 msw • Maximum speed 13.9 km/h (4.8 knots)• Cruising speed 6.5 km/h (3.5 knots)• Cruising range 148.2 km (80 n.miles)

PAYLOADThe DG2 EN payload, housed in a large container positioned on the upper stern side of the craft, is easily operated by the divers when the operational area is reached and is intended for attacks on moored or anchored vessels.The containers can be used to transport tactical payload or whatever is required to perform the mission, as well as any other tool as required by the mission.

HULLThe hull consists of three sections:• Stern section• Bow section• Middle sectionThe stern and the bow section are watertight and pressure resistant up to a depth of 100 metres while the middle section (cockpit) is free-flooded.The stern section houses the aft battery and the motor.The middle section has two control stations along the craft for pilot and co-pilot. These are enclosed by partially transparent canopies to improve the streamlined configuration of the craft and protect the operators from the flow of water and from sprays caused by the craft’s motion.

AIR SYSTEMThe breathing air for the divers is contained in two 50-litre cylinders (300 bar) fitted below the ballast tank in the middle area. A third small 10-litre cylinder (300 bar) is fitted nearby and contains the air for supplying the service circuits. The breathing air for the divers is contained in two cylinders fitted below in the middle area. A third small cylinder is fitted nearby and contains the air for supplying the service circuits.

TRIM SYSTEMA Trim & Buoyancy System is installed, maintaining a correct status and providing a solution for positive and negative buoyancy as well as longitudinal trim.

PROPULSION AND MANEUVERINGThe propulsion is silent thanks to the propeller’s design. The propeller is directly connected with the electric motor without any reduction gear, and thereby eliminating propulsion noise.The maneuvering system consists of hydraulically-controlled rudder, bow and stern planes that steer the craft both horizontally and vertically. Both pilot and co-pilot can perform the maneuvers or engage the auto-pilot system.

POWER SOURCE AND ELECTRIC SYSTEMThe power for the propulsion motor and the submersible electric pump is supplied by lithium batteries, chosen for their effectiveness, safeness and recharging speed. Furthermore the DG2 is designed to allow the replacement of a discharged battery pack with a charged one in an extremely short time, allowing the DG2 to be immediately ready for a new mission.

• Wired underwater communication system• Salvage buoy• Underwater camera• Surface spy buoy GPS + video (OPTIONAL)

UNDERWATER COMMUNICATION SYSTEMThere are two communication systems - one is a personal wireless system for each diver, and the other is an on-board wired communication system. During navigation, the fixed on-board system is used, providing an excellent solution in that this choice minimizes the risk of interception and does not use the batteries required by the wireless system, meaning that these will be fully charged for when the operators leave the SDV.

LOGISTIC SUPPORTLogistic support plays an essential role throughout the life cycle of the craft and, to that end, customers are provided with a support package that includes training, technical assistance, spare parts and maintenance programs.Great experience and tradition enable Drass to provide our customers with invaluable resources that include knowledgeable trainers and engineers, as well as adequate computer programs for the management of spare parts and periodical maintenance.

TRAINING SCHEMEWe provide a structured training scheme which comprises both operation and maintenance courses.The aim of the Operations training is to provide the crews with an accurate knowledge of the DG2 EN’s systems and equipment and provide them with the capacity to use the craft in all foreseeable situations. This part of the training includes theoretical classroom sessions, as well as practical sessions in the water on board the craft.

The batteries are fitted in two banks inside the two-battery compartments and series-connected through the Main Electric Motor cut-out which provides multiple voltage outputs to supply the Navigation System and all electrical components.

MAIN EQUIPMENT• Pilot control module• Co-pilot control module• GPS – Global positioning system • DVL– Doppler velocity log• Echo sounder• Obstacle Distance Measurement System• INS – Inertial navigation system• Wireless underwater communication system

The Maintenance training is directed to the client’s maintenance engineers and technical personnel, and includes focused sessions in the following areas:• Preventive Maintenance• Trouble Shooting• Corrective Maintenance• Integrated Logistic Support

TECHNICAL ASSISTANCEContinuous and prompt technical support is an important value-adding element. Specialized technical assistance is available throughout the product life cycle in order to satisfy the customer’s requirements.

SPARE PARTSDrass as a standard provides availability of spares for at least a 20 year period. Together with the craft we propose a set of spare parts sufficient to operate the craft for a period of 5 years based on an average activity. However, the amount of spares may be calculated case by case, and based on the specific requirements of the customer - such as: yearly activity forecast, total number of craft fleets, capacity to restore the components and systems locally.

COMPUTERIZED MANAGEMENT SYSTEMDedicated software is available for the integrated logistic support (spare parts and preventive maintenance). Such programs can be tailored and interfaced with the customer’s data management system.

OPERATIVE BASEDrass staff is available to help the end user with the design of the SDV base, where the crafts are recovered during the normal operational life and during maintenance activities.