DERV-2 Hydrogen Fuel Cell Mini-Sub
Class and type: DSRV-Mystic Mk. II Hydrogen Fuel Cell Mini-Sub
Displacement: 30.5 tons surfaced, 38 tons submerged
Length: 49 ft (15 m)
Beam: 8 ft (2.4 m); Width 11 ft (3.4 m)
Installed power: 60 shaft horsepower (0.8 kilowatt)
Propulsion: Electric motors, silver-zinc batteries, one shaft, four thrusters, hydrogen electric
Speed: 4 knots cruise, 16 knots max
Endurance: 225 days submerged at 3 knots (5.6 kilometers per hour), 25 days at 12 knots, 32 days at occupancy of 26.
Test depth: 5,000 feet (1,524 meters)
Capacity: 26 passengers, or 4 large Torpedoes, 16 Small Torpedoes, 2 missiles
Complement: 4 crew, and 26 passengers
Basic Information
DSRV-1 Mystic is a Deep Submergence Rescue Vehicle that is rated to dive up to 1500 metres. DSRV1 was built by Lockheed for the U.S. Navy and launched 24 January 1970. Mystic was launched on 24 January 1970. The submarine, intended to be air transportable, was 50 feet (15 m) long, 8 feet (2.4 m) in diameter, and weighed 37 tons. The sub was capable of descending to 5,000 feet (1,500 m) below the surface and could carry 24 passengers at a time in addition to its crew. The sub was stationed at North Island Naval Station in San Diego and was never required to conduct an actual rescue operation. Mystic was decommissioned on September 30, 2008. Designed as an alternative for traditional light craft, the submarine provides stealth, speed, and firepower not generally available to lighter craft. Due to it's depth in the water, it's not capable of being used like a drone, or unmanned, as radar cannot penetrate water anywhere near as effectively as it can in air, largely due to the density, necessitating human operators. In addition, the torpedoes must be self automated or wire guided, which makes them larger and more expensive, but generally more destructive than their counterparts.
The improved design sports a number of changes; the device utilizes a hydrogen fuel cell engine, instead of a zinc silver battery, which has approximately 250 times the energy density of the zinc silver battery; with a 60% efficient fuel cell, the device has over 150 times the efficiency, although with an internal oxidizer the weight efficiency drops to approximately 38 times that of a zinc silver battery, and allows for 1140 hours of transport, or 47.5 days while under water, or 190 above, with the equivalent weight. This is significantly greater range than the original battery, and allows for greatly increased range and operation time.
Additionally, the vehicle has weapons systems. While still capable of transporting over 28 members in a single transport, this can be replaced or augmented by direct action capabilities, ranging from large torpedoes, to missiles, to small torpedoes with AGM-114 sized explosives. The vehicle carries over 10 cubic meters of oxygen, or approximately 10,000 liters, or 2.4 billion at 240 bar, within steel containers, which by itself could last the vehicle at maximum occupancy approximately 8 days; with the rebreather circuit involved, this is over 30 days, as the rebreather recycles approximately 75% of the otherwise wasted air. Air is leaked into the cabin and recirculated back into the dive unit, where it is re compressed, and scrubbed of the carbon dioxide. This greatly extends the range of the vehicle, especially underwater; in addition, it is possible to dissociate the oxygen from the surrounding water for extremely long term underwater stays, or in emergencies, although the energy consumption is generally too large to make this particularly practical in regular transit.
Intended to be a small, small crewed submersible, the small submarine is set up primarily for two purposes- transport units covertly underwater, and to launch torpedoes from a small, small crewed close to undetectable platform. The vehicle itself utilizes new Torpedoes, much smaller in comparison, but fundamentally operating on the previous design. The Vehicle can be piloted by a single personnel, although four is generally implemented to more efficiently operate the weapons systems. Like most submersibles, the vehicle comes equipped with high-grade radios, sonar, and an underwater lightened camera.
The hydrogen fuel cell design allows a substantially quieter vehicle operation, reducing it's acoustic signature in the field; as well, it's non magnetic hull, designed after the Type 212, disallows easy maintenance from magnetic signatures; finally, it's sound absorbing hull makes it difficult to detect by sonar, and it's over-all small size means detection is unlikely if not simply impossible; it's size is also that of a small whale, making differentiation from whales also difficult in particular areas of the world. Active and passive sonar, magnetic detection, and other forms of detection allow for the easy detection of enemy units, including harder to reach figures such as small makeshift craft. These light boats can be easily targeted and destroyed by the actual ship itself, provided adequate tracking software.
The vehicle is capable of carrying and deploying two cruise missiles, be them AGM-84 harpoon missiles or BGM-109 Tamahawk cruise missiles. The vehicle is however designed to use a number of small torpedoes as it's primary armament, most notably the Mark. 54 MAKO, but can also use a wide variety of compatible torpedoes. Roughly 500-800 pounds and 8-10 feet in length, the Mark. 46 and Mark. 50 are also available, but the emphasis in general is placed on torpedoes small enough to fit on the craft, and cheap enough to justify their use. The craft has access to 8 independent torpedo tubes, in groups of 4 on both sides, with stacks of two torpedoes each. Despite their different sizes, the torpedo tubes are capable of stacking up two torpedoes of similar types in them.
By exploding beneath ships, the torpedoes can produce a vacuum from water displacement that can suck the ship down or capsize it; additionally, these torpedoes can have shaped charges in them, that usually target a craft and then go underneath them, targeting them from the bottom, and destroying the target. Finally, substantially smaller torpedoes, DERV- MK. 4,with explosive in similiar size to AGM-114 missiles can be utilized to pierce the armor of small vehicles, craft, or other targets, such as docks or decks. They can pierce the armor of potential submarines, although they are substantially weaker at doing so; they are also capable of skipping across the water, and impacting the side of a boat, instead of underneath.
