Same unit, any role
Main display or repeater is a firmware setting. Buy one unit to start and add more later: no special repeater model.
SailNav Crew · for keelboats 6–10 m
One system. Every crew position.
A masthead wind sensor on NMEA 2000, sunlight-readable panel displays, and repeaters wherever your crew looks: helm, mast, companionway or chart table. Built for club racers and small cruisers.
Photo composite, product rendering. Photo: Marc Wieland, Unsplash
System overview
Plugs into your boat's network.
SailNav Crew speaks NMEA 2000 and NMEA 0183 and runs on 12 V boat power. The wired masthead sensor is powered by the bus. Add repeaters on the backbone, or wirelessly where running a cable is a pain.
- 1 Masthead wind sensor, wired on NMEA 2000 and powered by the bus: cups and vane on a 0.6 m arm (1.0 m option)
- 2 Main display, panel-mounted at the companionway or bulkhead
- 3 Wired repeater: the same unit, set to repeater in firmware, on the NMEA 2000 backbone
- 4 Wireless repeater over Bluetooth LE from the main unit, for easy retrofits
- 5 Other NMEA 2000 devices: speed log, depth, autopilot, chartplotter
- 6 NMEA 0183 input and output for older devices such as a VHF or AIS
- 7 12 V boat power, from the bus or a dedicated terminal
Diagram simplified. NMEA 2000 networks need a powered backbone with two terminators. NMEA 2000® is a registered trademark of the National Marine Electronics Association; SailNav has not been NMEA-certified yet (certification planned).
The display
Big numbers. Readable in full sun.
A 4.4" reflective memory-in-pixel screen that gets clearer the brighter the sun, four sealed keys, and a flush panel mount that sits only about 17 mm behind the bulkhead.
- Sunlight readable: reflective display, high contrast from any angle in daylight.
- Sensors built in: GNSS, 9-axis motion sensor, magnetometer and barometer. It works as a GPS speed, heading and heel instrument even before you connect anything.
- Built for the cockpit: sealed front, stainless screws, gasketed panel mount.
Repeaters
Put the numbers where your crew looks.
The helmsman wants target speed, the trimmer wants apparent wind, the tactician wants the shifts. Every repeater is the same SailNav display with its own page, so each crew member sees what they need.
Wired on NMEA 2000
The preferred installation: one drop cable per repeater on the backbone, with power and data in the same cable.
Wireless for retrofits
No cable run to the mast or the helm? A repeater can receive its data over Bluetooth LE from the main unit instead.
Masthead wind sensor
Cups and vane, out in clean air.
The keelboat sensor uses three conical cups for speed and a separate vane for direction, on a GRP arm that reaches forward of the mast, away from its disturbed air.
- Wired NMEA 2000 version: one cable down the mast, powered by the bus, works on any NMEA 2000 network.
- Wireless option for retrofits: the wind-powered head with a hermetic cell, no cable through the mast at all. About 300 g including arm and bracket est..
- 0.6 m arm, 1.0 m option. The vane sits on the tip, farthest from the mast; the display applies an upwash correction.
- Masthead motion correction: the display's motion sensor measures the mast's roll and pitch and removes it from the wind reading.
Wiring options
Every way to connect.
| Connection | What it is for | Details |
|---|---|---|
| NMEA 2000 | Wind sensor, repeaters, other instruments, power | M12 A-coded connector on the rear; load equivalency LEN 3 (≤ 150 mA) |
| NMEA 0183 in | Older GPS, VHF, AIS, instruments | Opto-isolated listener input |
| NMEA 0183 out | Send wind and heading to an 0183 device | Talker output, protected against faults up to ±70 V |
| 12 V terminal | Boats without an NMEA 2000 backbone | 9–16 V input, survives 33 V and reverse polarity |
| Bluetooth LE 6 | Wireless wind head, wireless repeaters, phones | Nordic nRF54LM20A |
| USB-C | Service, firmware updates, bench power | On the rear of the unit |
Connect either NMEA 2000 or the 12 V terminal, not both at once. Installation details will be in the manual.
Technical data
SailNav Crew at a glance
Pre-production data. Values marked target are design goals or engineering estimates, to be confirmed by testing.
| Panel display (main unit or repeater) | |
|---|---|
| Screen | 4.4" reflective memory-in-pixel, 320 × 240 (Sharp LS044Q7DH01), sunlight readable |
| Night use | No backlight in the current design; night-lighting options under evaluation |
| Controls | 4 sealed keys |
| Processor and radio | Nordic nRF54LM20A (Fanstel BM20C module), Bluetooth LE 6 |
| Positioning | u-blox MAX-M10S GNSS, built-in antenna (external antenna option) |
| Motion and weather | 9-axis IMU with sensor fusion (BNO085), magnetometer, barometer |
| Interfaces | NMEA 2000 (M12), NMEA 0183 in and out, 12 V terminal, USB-C |
| Power | 12 V boat power: NMEA 2000 bus (LEN 3) or 9–16 V terminal; internal LiPo backup battery |
| Installation | Flush panel mount, about 17 mm behind the panel prototype CAD |
| Role | Main display or repeater, set in firmware; repeaters wired (NMEA 2000) or wireless (Bluetooth LE) |
| Masthead wind sensor | |
| Type | 3 conical cups (wind speed) + separate vane (direction) |
| Standard version | Wired, NMEA 2000, bus-powered |
| Retrofit option | Wireless, wind-powered, hermetic cell, Bluetooth LE broadcast at 4 Hz; ≈ 300 g incl. arm and bracket est. |
| Arm | GRP tube, 0.6 m (1.0 m option), pointing forward, stainless bracket |
| Direction sensing | Contactless magnetic (3D Hall) |
| Corrections | Heel, masthead motion and upwash corrected in the display |
Kickstarter · coming soon
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