Sula 5 Coastal Unmanned Surface Vessel

Sula 5 is a 4.9 m unmanned surface vessel, battery-electric or with a 40 hp outboard, for harbour and near-shore sea work. It is the smallest of our platforms we configure for a towed production magnetometer such as the Geometrics G-882, and it carries a parametric sub-bottom profiler such as the Innomar SES-2000, a towed side-scan on a reel, USBL tracking and Starlink. We configure each boat to order, with RTK GNSS position and dual-antenna heading as standard.

Platform specification

Sula 5 comes in an electric and a fuel version.

	Sula 5
Length	4.90 m
Beam	1.95 m
Draft	56 cm
Mass	350 kg empty
Payload	Up to 600 kg
Hull	Polyethylene (PE) and other materials
Propulsion	Electric version: two 5.5 kW electric motors. Fuel version: 40 hp outboard
Endurance	3 h (electric); 8 h (fuel)
Maximum speed	12 km/h (6.5 kn), electric; 45 km/h (24.3 kn), fuel
Comms	4G, 5G and satellite
Water	Lakes, rivers, reservoirs, harbour waters and near-shore sea areas

Payloads Sula 5 takes

Everything Sula 2 takes also fits. Sula 5 adds:

Payload	Example models	Mount	Note
Towed magnetometer or gradiometer	Geometrics G-882, G-882 TVG; Marine Magnetics SeaSPY2, Explorer, SeaQuest2; SENSYS MX3D	Towed	One tow. A G-882 fish weighs 18 kg and draws 12–16 W running. Layback keeps the sensor clear of the hull’s magnetic signature.
Parametric sub-bottom profiler	Innomar SES-2000 compact, SES-2000 standard	Hull	Needs a survey INS. The SES-2000 compact has a transducer of about 22 kg with 20 m of cable and a topside of about 15 kg, and draws 50 W typical, 100 W at most.
Side-scan sonar, towfish with reel and depressor	EdgeTech 4125i; JW Fishers 450/900 CHIRP with CMS-2 reel and DDW-1 depressor	Towed	A heavier towfish needs a tow point and recovery gear on a larger hull.
USBL for a towed body	Blueprint Subsea SeaTrac X150 with X010 beacon; Sonardyne Micro-Ranger 2	Hull	Positions the tow. Layback from a winch cable counter is the cross-check.
Starlink	Starlink Flat High Performance	Mast	Satellite broadband back to shore.

Where Sula 5 stops. It runs one tow at a time. Step up to Sula 8 for the full UXO system: a gradiometer and a side-scan as two tows, a sub-bottom profiler with survey INS, USBL and a powered winch, with Iridium Certus satcom as a backup to Starlink. Step down to Sula 2 for multibeam, light side-scan and camera work from a hull that fits in a van or on a small trailer.

Applications

• Offshore-wind UXO magnetometer survey with a single tow, in near-shore water. Sula 5 is the smallest of our platforms we configure for a G-882 tow.
• Cable-route survey. Parametric sub-bottom profiling and towed side-scan along cable routes near shore.
• Coastal multibeam in harbours and near-shore water, for up to 8 h on the fuel version.
• Towed side-scan survey with a towfish on a reel and depressor, tracked by USBL.
• Port security and harbour inspection with a sensor mast, AIS and Starlink back to shore.

Sula 5 works on lakes, rivers and reservoirs, in harbours and in near-shore sea areas. Endurance depends on the version: 3 h for the electric version, 8 h for the fuel version.

Navigation

Standard: RTK GNSS position with dual-antenna heading. With survey payloads aboard, one survey GNSS/INS is the reference for every sensor, with PPS time sync. The RTK correction feed comes from a base station on site or from network corrections over mobile data.

Option: anti-jam navigation. Pro is the natural tier for Sula 5, and the Base set also fits.

• Pro: a multi-element CRPA with null-steering, a tactical-grade fibre-optic-gyro (FOG) inertial unit, and a flush-mount surface-vessel Doppler velocity log (DVL) in a sea valve or bell housing.
• Base: a filtered anti-jam antenna, a compact inertial unit of industrial (MEMS) or lower tactical grade, and a compact DVL.

With either set, spoofing detection with automatic source switching is configured and integrated per boat, and integration with the autopilot is available. DVL bottom-lock needs the seabed within range, which means shallow and coastal water; in deep water the DVL falls back to water-track, and drift then depends on the inertial unit’s grade. More on the tiers: GNSS-denied USV navigation.

Integration and support

Integration	Payload fitted, wired and calibrated on the hull, with sensor offsets and parameters set and the RTK correction feed configured. Autopilot integration is available.
Delivery	Commissioning on your water, operator training, and support from our UK and EU teams.
Ordering	Configured to order, quoted per boat.

Questions and answers

What is the smallest unmanned surface vessel that tows a G-882 magnetometer?

Of our platforms, Sula 5 is the one we configure for a G-882 tow. The smallest hull with a record of towing Geometrics G-882 magnetometers on offshore-wind UXO survey is 4.5 m long. A G-882 fish weighs 18 kg, and the tow needs force and enough layback to keep the sensor clear of the hull’s magnetic signature.

Can a coastal USV run a full UXO survey system?

It runs one tow. The full system tows a gradiometer and a side-scan together and adds a sub-bottom profiler with survey INS, USBL and a powered winch. That needs a second tow point and an offshore hull: Sula 8.

Can a coastal USV carry a parametric sub-bottom profiler?

Yes, comfortably. An Innomar SES-2000 compact has a transducer of about 22 kg with 20 m of cable and a topside of about 15 kg, draws 50 W typical and 100 W at most, and needs a survey INS. Sula 5 takes up to 600 kg of payload.

How long can a coastal USV stay at sea?

Sula 5 runs 3 h in its electric version and 8 h in its fuel version.