Side-Scan Towfish

Side-Scan Towfish

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Capable of wide-beam scans, MarineNav's Side-scan Towfish sonar system serves as a perfect complement to your ROV fleet, replacing the need for destructive bottom dredging or expensive dive teams. MarineNav wide-beam scan sonar systems are ideal for preliminary assessment of potential target areas capturing anomalies that can be reviewed and marked with geo-markers for future ROV exploration.

Phone: +44 (0) 1330 705050


MarineNav’s portable Side-scan Sonar Towfish system is a portable sonar that is easily transported and deployed to scan large areas of the seabed to spot anomalies, wrecks, ghost gear and other objects. The Side-scan Towfish sonar is connected by a strain relief rope and towed behind your vessel as it is in motion. Conduct a smooth survey of a target area simply by lowering or raising the sonar to a fixed depth, thus eliminating potential pitch and roll that may affect the quality of data capture. With GPS integrated into the topside case built-in screen, the Side-scan Towfish sonar can also be used as a chart plotter and is compatible with most marine map software, including Navionics, to provide detailed nautical navigation charts.

Eliminate blind searches normally performed by grapples, divers or ROV systems. Save time by conducting wide sweep scans to track, mark and record GPS positions of interest.

Shipped in IP-rated waterproof hardshell transport cases.

Shipped in IP-rated waterproof hardshell transport cases.

Detail of Side-scan Towfish topside case.

Create waypoints and record GPS locations of any anomalies.

Detail of the Side-scan Towfish topside built-in Humminbird control system.

Choose between DC, AC or built-in battery source.

Detail of the Side-scan Towfish.

Adjust the pitch of the Towfish with a built-in ballast system in the nose cone and a top-mount tether plate with multiple connections.

The Side-scan Towfish system includes a Towfish outfitted with sonar, one topside control system, 45 feet connecting tether with strain relief cable and locking shackle.


Quick deployment and surveying capabilities

Plug the Side-scan Towfish connecting cable, power up the sonar topside case, and deploy the tow-fish over the side of a boat or from a Davit and start surveying an area in under five minutes.

Choose between DC, AC or built-in battery source

The Side-scan Towfish topside includes a built-in option that allows users to choose from a DC power source (9-36V DC), an AC power source (120/240V AC), or access to a built-in battery source (built-in connectors for two plug-in Dewalt brand batteries).



Three adjustable sonar frequencies

Adjust sonar to 3 adjustable frequencies of 455Khz, 800Khz or 1.2Mhz. Higher frequencies provide more detailed seabed scans, while lower frequencies increase the sonar scan range. At 455Khz, the Side-scan Towfish scans up to 235m (800 ft) on either side of your vessel.

Create waypoints and record GPS locations

Identify found objects and anomalies in real-time, and mark targets by creating touch-activated waypoints that record GPS coordinates. Review sonar sweep data frame-by-frame, fast forward, reverse and pause command functions allow users to focus on keyframes to assess possible anomaly targets. All recorded data is saved to the topside control system solid-state drive for future dive missions.


Standard features include

  • Rugged construction, hard shell cases for ease of transport

    Manufactured from marine-grade materials and with a minimum of moving parts, the Side-scan Towfish ships in IP-rated hard shell transport cases.

  • 45 ft length of connecting cable, strain relief rope and locking shackle

    Collected data from the Side-scan Towfish is delivered to the topside control case through a 45-foot length of connecting cable. A strain relief cable and easy-to-connect locking shackle protect the Side-scan Towfish sonar during flight.

  • Control Tow Fish pitch and flight behaviour

    Design features such as a large pre-drilled connecting plate with an array of attachment holes and adjustable ballast weight in the nose cone allow users to easily adjust the pitch and flight behaviour of the Towfish sonar.

  • Topside case equipped with 13" Multi-function display

    View streaming data in real-time on a 13-inch multi-function display. Built-in software allows users to review data on the fly, pause, reverse or jump forward to view keyframes for potential anomalies.

  • Built-in AC, DC and battery connection ports

    Choose between power modes for any situation. Internal rechargeable battery docking stations allow for remote operation away from power sources.

  • 32 GB data storage topside

    The topside's multi-function display captures data on a removable 32 GB SD card capable of storing hours of data.

  • Protected by a one-year limited warranty*

    The Side-scan Towfish includes a one-year limited warranty extended to all MarineNav-manufactured components within the system.

Terms and conditions

*MarineNav-built sonars are protected by a one-year limited warranty upon registering the product within the first 3 months of purchase. The one-year warranty extends to all components manufactured by MarineNav. Third-party multi-function displays and other third-party components are not protected by MarineNav warranties. Consult third-party manufacturers' websites for warranty terms and conditions. Other conditions apply.

x While we strive to ensure the accuracy of all items and descriptions in this document, this is not always possible. Specifications, options, pricing and availability are subject to change without notice. Errors and omissions excepted. We reserve the right to limit quantities.