Vetus retractable and hydraulic thrusters

Most Vetus thruster sales are tunnel units, either the on/off BOW or the proportional BOW PRO. This page covers the two specialist lines for boats where a normal tunnel is the wrong answer: the STE retractable for boats without the depth for a tunnel, and the hydraulic range for boats that need thrust for longer than a DC motor will give it.

Part one: STE retractable thrusters

Who it is for

Vetus pitches the STE at shallow-draft boats and at sailboats with cutaway forefoots or raised sterns. Those are the hulls where a tunnel either cannot be placed deep enough or would sit right at the waterline and suck air. On a sailboat there is the drag argument too: a tunnel is a permanent hole that costs a little speed every time you sail.

How it works

The STE is a swing design. The thruster pivots down out of the hull on a permanently lubricated bearing, and Vetus says there are minimal moving parts. The propeller turns in a short duct for a focused jet. When retracted, a bottom plate attached to the duct closes off the opening to reduce drag.

A few details show some thought about real use:

• It retracts automatically when you switch off the control panel, or if it sits unused for 15 minutes. Forgetting to stow it should not leave a thruster hanging under the boat at hull speed.
• Electronic protection guards the swing mechanism against overloads and jamming.
• There is a 1.5 second delay between direction changes to spare the gears.
• Control runs over V-CAN, Vetus's CAN bus.

The range

All four are 12V, on/off, and built on the standard Vetus DC thruster, so the motors and run times line up with the BOW range. Vetus lists the STE7512D at 31 kg and the STE9512D at 42 kg.

Sizing

Vetus does not publish boat-length guidance on the STE pages, but because each STE is built on the matching DC thruster, the BOW guidance is a reasonable reference: the BOW5512D is listed for 26-39 ft, the BOW6012D for 27-40 ft, the BOW7512D for 30-45 ft and the BOW9512D for 36-55 ft. A retractable sitting deeper in clean water may perform a little differently from a tunnel unit, and sailboats with tall rigs carry more windage than their length suggests, so run the numbers through the sizing calculator before choosing.

Where it falls short

The range stops at 95 kgf and 12V. There is no proportional or brushless version listed, and the 2-5 minute run times are the same short ratings as the on/off tunnel units. If you need more thrust, 24V or 48V, or variable speed in a retractable, Sleipner's SR/SRL/SRV range covers all three, and Max Power's retracts are worth comparing too.

Install notes

Like any retractable, this means a hull opening and a reinforced mounting area, plus enough space above the hull for the unit to swing up. Check headroom in the forepeak and the shape of the hull where the pod will sit. Current draw is the same as the matching tunnel unit: 500-610 A on the two larger models, so the cable and battery need the same care. Our retractable installation page explains the process.

Part two: hydraulic thrusters

The range

Vetus's hydraulic tunnel thrusters run from the BOW55HMD to the BOW310HMD:

• BOW55HMD: 55 kgf, 150 mm tunnel, 3.5 kW
• BOW95HMD: 95 kgf, 185 mm, 6.0 kW
• BOW160HMD: 160 kgf, 250 mm, 12.3 kW
• BOW230HMD: 230 kgf, 300 mm, 16.4 kW
• BOW310HMD: 310 kgf, 300 mm, 26.8 kW

Above that, the BOWH410 and BOWH550 use a 400 mm tunnel with 29.5 kW and 39 kW listed. The older BOW550HM is marked discontinued.

Why hydraulic

Vetus says its hydraulic thrusters offer virtually unlimited running time and do not need electrical connections at the thruster or pump. They fit tunnels made of GRP, steel or aluminum, which suits workboats and steel cruisers. Vetus also lists proportional control options.

The power source is flexible. Vetus says you can run them from an existing hydraulic system with enough flow and pressure, from a pump on the main engine, or from a specially prepared diesel power pack that includes the matching pump. Vetus points out that a power pack can also reduce the generator capacity a boat needs, by running hydraulic loads that would otherwise be electric.

Install notes

The thruster end of a hydraulic install is simpler than an electric one: no heavy DC cables, no thruster battery, no main fuse. The complexity moves to the engine room. You need a pump with enough flow at the RPM you dock at, a control valve, a reservoir with enough capacity and cooling for long runs, and hose routing forward that can be inspected. On steel and aluminum boats, Vetus offering the thrusters to suit metal tunnels is a real convenience.

Where it falls short

The range is narrower than Sleipner's SH series, which goes from 185 mm up to 730 mm tunnels. And as with any hydraulic thruster, the real work is in the system: pump sizing, valves, cooling and hose runs. See our electric vs hydraulic comparison and the Sleipner hydraulic review for a sense of the alternatives.

Verdict

The STE swing thruster is a sensible solution for a narrow but real problem: sailboats and shallow hulls that need a hidden thruster of up to 95 kgf on 12V. Outside that, its limits show. Vetus's hydraulic range is a solid option for boats in the 55-310 kgf class that already run hydraulics or want a power pack, especially steel and aluminum hulls. If your boat fits either case, get in touch and we will check the hull and the space.

Questions people ask