The Stalcaire-class Unmanned Surface Vessel is a small, unmanned and armed vessel built by Silverport Dockyards Limited, intended for patrol and combat. Being, by nature of an unmanned vessel, cheaper in upkeep and maintenance then a manned surface vessel, of similar size, the Stalcaire-class Unmanned Surface Vessel is the ideal solution for countries with limited budgets and manpower, which have to cover and patrol a lot of sea, or who simply want to leave the tedious jobs of a Navy to the capable, yet cheap solution.

The term stalcaire means stalker, a huntsman engaging in a technique of hunting without hounds, horses or similar loud attachments. Vessels of this class are built by SDY's subsidiary Bád Industries Limited of Cuan and were developed together with the SDF-Navy and Gabha Blacksmiths Limited.


The Stalcaire-class Unmanned Surface Vessel is a trimaran with two outriggers, or Ama, connected to the main hull, the Vaka, by the ways of a crossarm, or Aka. This hull form provides greater speed and stability, as well as less draught, allowing the vessel to operate in littorals very close to shore.

Built with a reduced radar-signature in mind, the Stalcaire-class Unmanned Surface Vessel is harder to detect, but not impossible to detect. The small vessel appears on radars around the size of a small fishing boat.

The vessel of non-magnetic steel is 35.2 metres in length, has a total beam of 6.2 metres and a maximum draught of 1.1 metres at a displacement of 165 tons standard displacement. Due to requiring no crew present, the Stalcaire-class Unmanned Surface Vessel can use all the space needed for the upkeep of sailors to store fuel, electronic systems and other things necessary for operation, including a small freight compartment for 150 kilograms of freight. The vessel is hardened against EM-Pulses.

Powered by four diesel generators, producing a total of 16,000 kW, being the same generators as used on the Spéirling-class Fast Attack Craft. The propulsion arrangement is called Integrated Electric Propulsion, IEP for short, where the Diesel Generators produce electrical power, thus saving space, maintenance costs and providing a simple, cheap and reliable way of power generation, which power everything aboard the Stalcaire-class Unmanned Surface Vessel, from the propulsion systems to the radars.

The vessel is driven by two pump-jets with thrust vectoring, which also allow for reversing via a reversing bucket, decreasing the acoustic signature as well as increasing the manoeuvrability (somewhat balancing the inherited disadvantages of a trimaran-hull) and the operational space in littoral waters.

The Stalcaire-class Unmanned Surface Vessel can reach a maximum speed of 45 knots, or 83.3 knots, as well as a range of 10,000 nautical miles, or 18,520 kilometres, at a cruise speed of 12 knots, or 22.2 knots. Replenishment at Sea is possible.

Maintenance is completed either in a drydock, by dragging the vessel ashore, in a well deck or even in a freighter's cargo bay, provided the vessel can be lifted into the freighter. Maintenance entrances and narrow hallways, as well as a modular architecture with triple-redundant data-busses, allow for easy and cheap maintenance. However, before accessing the vessel, it is recommended to provide the corresponding passwords as otherwise, the Stalcaire-class Unmanned Surface Vessel's computer systems believe the vessel to be captured and will detonate all ammunition remaining onboard and a number of plastic explosive charges intended to completely destroy the vessel and its capturers.

Command and Control

The Command and Control Systems of the Stalcaire-class Unmanned Surface Vessel know four modes, Direct Control, Observation Modes A and B, as well as autonomous.

Direct Control means a human operator using a control station – the one used for the Foiche Mark I UCAV (the Cráinfhoiche Control Station) can be used, but we recommend the more specialized Macánta Control Station, which is included in the delivery – to control every aspect of one Stalcaire-class Unmanned Surface Vehicle. The Macánta Control Station can either be used in a direct line-of-sight capability or use satellite communications to send commands and receive data with a delay of up to 1.1 seconds. Said commands and data are, to prevent disruption of communications or even hacking by other sources, transmitted via an ECM-resistant, frequency-hopping device with additional encryption. With the necessary codes provided, the control of a Stalcaire-class Unmanned Surface Vessel can be handed to and from operator to operator, as well as taken over after the vessel has autonomously reached its destination area. Controllers using this mode came to call it the 'Boat Simulator Mode' or BSM.

Observation Mode A is defined as a human always (or nearly always) receiving data of the vessel, observing the surroundings freely via the vessels sensors. Observation Mode B is the extension of that, the human operator being in control of all the important bits, for example weapons usage, destination, course and so on. While Observation Mode A can be engaged basically from a home computer (provided the corresponding software and infrastructure is available), Observation Mode B needs a Macánta Control Station. Both Observation Modes can not only be utilized to control or observe a singular vessels, but also a flotilla. Controllers using Observation Mode A use to call this mode the Screensaver Mode, while Observation Mode B is called the RTS-Mode.

The Stalcaire-class Unmanned Surface Vessel can also operate autonomously, including weapons usage, along pre-defined Rules of Engagement. The Builder for these Rules of Engagement is simple to handle and easy to understand, including settings about IFF-Systems. It is entirely possible for the Stalcaire-class Unmanned Surface Vessel to move to a target area, patrol there, and, as soon as something has been found, switch to one of the Observation Modes or Direct Control Mode if programmed to do so.

Should the vessel loose contact to the control station without that being planned, it will turn on the autonomous operating system and set course for the nearest, pre-defined friendly harbour. Should the vessel be captured, it will destroy itself as described above.

After a test, an officer of the SDF-Navy remarked, that operating the Stalcaire-class Unmanned Surface Vessel or even a group of these vessels looked and felt a lot like playing a video game and was equally simple (hence the different operation modes' nicknames).


The Stalcaire-class Unmanned Surface Vessel is equipped with a number of sensors for operations, including a simple and cheap, but also reliable Nuacht N-12 Air/Surface Search Radar, a Multi-Function Radar capable of acting as an air search radar, surface search radar, navigation radar and even fire-control radar, all while operating on different bands.

A hull-mounted sonar completes the sensor suit. This sonar can be used for mine-hunting, submarine-hunting and for pretending to be someone else as this sonar can also send out noise which make the Stalcaire-class Unmanned Surface Vessel look like another vessel on sonar, for example like an aircraft carrier or a harmless freighter.

Electronic Warfare and Decoys

In addition to the EP-suit for securing communications with the Control Station described Above, the Stalcaire-class Unmanned Surface Vessel is equipped with an ECM-suit, capable of jamming enemy communications and radar.

Adding to that is a SIGINT-Suit, a suit of systems capable of catching, analysing and matching electromagnetic emissions of all sorts of sources, thus identifying enemies in conjunction with the appropriate databases. However, the Stalcaire-class Unmanned Surface Vessel is not capable of deciphering enemy transmissions, only analysing who is talking to whom in which quantity. Radio messages intercepted are usually recorded and stored for the return to harbour, where they can be deciphered.

The Stalcaire-class Unmanned Surface Vessel is also equipped with simple launchers for chaff and flares, which are used to confuse enemy sensors.


The Stalcaire-class Unmanned Surface Vessel is equipped with a number of weapon systems to accomplish its mission, amongst them six box launchers for anti-ship missiles, a rail for mines and depth charges (up to twenty mines can be carried), two 30mm CIWS and three Remote Weapons Stations.

The Ceantar C-84 30mm CIWS is a close-in weapons systems used for point defence on many military vessels built by SDY. Used on the Stalcaire-class Unmanned Surface Vessel is the model Mark III, which is fully autonomous. With its own small radar, it can search for, acquire and combat targets at a range of up to seven kilometres spewing 4,500 rounds in a minute from six barrels with a muzzle velocity of 950 metres per second using caseless ammunition from a 3,000 round 'magazine'.

In addition to that, the Stalcaire-class Unmanned Surface Vessel is equipped with three Remote Weapons Stations, one of them heavy, positioned on the bow, two light ones on balconies on either side of the small superstructure. There are many possibilities for how to equip these remote weapons stations, for example the SDF-Navy plans to equip the ones they ordered with a 40mm multi-purpose gun on the bow and the Machine Gun, Grenade, Model 1990, a 40 millimetre automatic grenade launcher fed by a 100 rounds belt with a maximum range of 2,000 metres, produced by Gabha Blacksmiths Limited on the balconies. All Remote Weapons Stations are delivered empty.


It has always been a dream to send unmanned vessels to patrol and take care of the more tedious jobs of a navy or to provide auxiliary functions – or even to fight, without risking life and limb of living soldiers. Especially for countries with limited budgets and manpower, or unwillingness to risk life and limb of its soldiers, such systems are very tempting.

Remote control of vessels at sea is nothing new or unusual, a target vessel of the SDF-Navy had been remote-controlled in the 30s and 40s until SDFAS Crach (Ex-LNS Fuoco) was finally sunk in 1948 in one of the first tests of autonomous air-launched Anti-Ship Missiles. However, these systems were expensive, cumbersome and could do little more then a remote-controlled car: Move from Point A to Point B.

With time, however, things became more and more sophisticated, but mostly constrained to small vessels remote-controlled by the universities as proofs of concepts and joy in experimentation. With more and more systems being digitally controlled, however, the options of remote-controlling a vessel, or vehicle in general, became more and more interesting to the military again. Drones were born.

In the 1990s, the SDF-Navy began first experimenting with unmanned surface vessels, as part of the FAC-Testing Force in Silverport, but those experiments were under-funded and treated like a number of orphans, but the FAC-Testing Force, together with SDY, Gabha Blacksmiths Limited and the University of Silverport, made a few important advances, including autonomous operations of a vessel in sea traffic lanes and remote controls of a vehicle (which would also prove important in the development of the Foiche Mark I Unmanned Combat Aerial Vehicle of Gabha).

In 2003, a Fiagai-class Patrol Vessel was re-purposed as a testbed for hand-on research.

And so it bobbed up and down for years – until the Battle of Marley Bay in 2012. Due to the losses of the SDF-Navy, which are usually described as catastrophic, the Navy sought new methods and technologies to give balance out the losses... and someone remembered the Unmanned Surface Vessel Project.

Equipped with new purpose, not to mention funding, the FAC-Testing Force and SDY went to work to put the first prototypes to sea in 2015 and 2016, testing them until 2017. Based on these test results, the Stalcaire-class Unmanned Surface Vessel and its siblings and cousins were developed.

A number of civilian versions of the Stalcaire-class Unmanned Surface Vessel are planned.

In 2018, the 1st and 4th Patrol Gunboat Squadrons were equipped with these vessels.

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