The essentials in 30 seconds
- 9 inches = standard coastal. Readability 1 m, max 4 windows (chartplotter / depth sounder / radar / instruments). Suitable for 25-35 ft sailboats for coastal use. Budget ~ $1,500-2,000 USD (Raymarine Axiom+ 9 or B&G Vulcan 9).
- 12 inches = standard offshore. Readability 1.5 m, up to 6 windows, simultaneous split-screen charting + radar + AIS + depth sounder. 35-50 ft sailboats. Budget ~ $2,800-3,800 USD (Raymarine Axiom Pro 12 or B&G Zeus 3S 12).
- 16+ inches or multi-screens for yachts 50+ ft. Glass-helm solution (Axiom Pro 16, Zeus³S Glass Helm) or 2 × 12 inches side by side. Budget $6,000-12,000 USD.
- Brand choice depends on the ecosystem. Raymarine = versatile cruising (Quantum radar, EV-100 autopilot, ClearCruise IR integration). B&G = racing (H5000 integration, polars, laylines). Garmin = fishing + chartplotting.
- Workshop verdict: 60% of Skysat refits in 2026 go for 12 inches. The ~$1,000 USD difference between 9 and 12 inches is justified by readability in rough seas + multi-window capability.
The GPS-sounder combo is the navigation brain of the modern sailboat. Charts, radar, AIS, depth sounder, instruments — everything converges on this screen. Choosing its size (9, 12, 16 inches) impacts safety (readability), comfort (multi-window), and budget (differential $1,000-3,000 USD per tier).
This article distinguishes uses by screen size and presents the references distributed by Skysat. For the charts that feed the chartplotter, see our marine charts 2026.
Why screen size matters
Three technical criteria separate screen sizes:
- Readability distance based on resolution (typically 1,280×800 on 9", 1,920×1,080 on 12"). 9" readable up to 1 m, 12" up to 1.5 m. On a 40 ft sailboat with helmsman 1.2 m from the combo, the 12" doubles useful readability.
- Simultaneous multi-windows. 9" = max 4 windows before illegibility. 12" = 6 windows (50% charting + 25% radar + 12.5% AIS + 12.5% instruments). In busy coastal navigation, the advantage is tangible.
- Touch vs buttons. All modern 2026 models are touchscreen (glove-resistant, saltwater-proof). 9" remains usable with a fingertip. 12" allows true multitouch ergonomics (two-finger zoom, swipe between windows).
9 inches — standard coastal use
The 9-inch is the modern entry point. Suitable for 80% of 25-35 ft sailboats for summer coastal use.
- Raymarine Axiom+ 9: ~ $1,800 USD. HydroTouch touchscreen, 2 GHz processor, internal GPS, native Quantum radar + EV-100 autopilot integration.
- B&G Vulcan 9 R: ~ $1,900 USD. Backlit touchscreen, H5000 integration, polars, laylines. Preferred for racing.
- Garmin GPSMAP 923xsv: ~ $2,100 USD. Touchscreen + buttons (mixed), excellent for fishing, CHIRP sonar integration.
12 inches — comfortable offshore use
The 12-inch becomes essential when leaving summer coastal waters. 35-50 ft sailboats for offshore cruising, IRC racing, transatlantic passages.
- Raymarine Axiom Pro 12: ~ $3,200 USD. Buttons + touchscreen, ambient sensors, integrated SD reader, ClearCruise IR integration (thermal camera).
- B&G Zeus 3S 12: ~ $3,500 USD. Glass touchscreen, 8-core processor, complete H5000 Performance integration. European IRC racing standard.
- Garmin GPSMAP 1223xsv: ~ $3,400 USD. Touchscreen + buttons, excellent for remote areas (Quickdraw Contours, ActiveCaptain).
Multi-screens and glass-helm
For 50+ ft yachts, the common solution is multi-screens:
- 2 × 12 inches side by side: main chartplotter + dedicated depth sounder. ~ $7,000 USD complete install.
- Axiom Pro 16 or Zeus 3S 16: single XL screen. ~ $5,500-6,500 USD.
- B&G Zeus³S Glass Helm 16-inch pack with GPS, ZC2 keyboard ($6,618 USD): premium B&G turnkey solution.
2026 model comparison chart
| Model | Size | Resolution | Brand | Price USD |
|---|---|---|---|---|
| Axiom+ 9 | 9" | 1,280×800 | Raymarine | ~ $1,800 |
| Vulcan 9 R | 9" | 1,280×800 | B&G | ~ $1,900 |
| GPSMAP 923xsv | 9" | 1,280×800 | Garmin | ~ $2,100 |
| Axiom Pro 12 | 12" | 1,280×800 | Raymarine | ~ $3,200 |
| Zeus 3S 12 | 12" | 1,920×1,080 | B&G | ~ $3,500 |
| GPSMAP 1223xsv | 12" | 1,920×1,080 | Garmin | ~ $3,400 |
| Zeus S 3015 UltraWide | 15" | 2,560×1,080 | B&G | ~ $4,800 |
| B&G Zeus³S Glass Helm 16 Pack | 16" | 1,920×1,080 | B&G | ~ $6,618 |
Workshop verdict by program
25-30 ft sailboat, summer coastal sailing
9-inch budget = Raymarine Axiom+ 9 (~ $1,800 USD) or B&G Vulcan 9 R. Total install ~ $2,200-2,500 USD.
35-45 ft sailboat, offshore cruising
12-inch = Axiom Pro 12 or Zeus 3S 12 (~ $3,200-3,500 USD). Skysat workshop standard since 2022. Total install ~ $4,000-4,500 USD.
45-55 ft sailboat, mixed cruising + racing program
Zeus 3S 12 + ZC2 remote = ~ $4,000 USD. If Raymarine ecosystem, Axiom Pro 12 + secondary Axiom Pro 9.
50+ ft yacht, pure racing or yacht charter
B&G Zeus³S Glass Helm 16 ($6,618 USD) or Zeus S 3015 UltraWide 15" (~ $4,800 USD) + 2nd 12" screen. Total ~ $8,000-12,000 USD complete install.
5 installation errors observed
Combo errors — Skysat workshop
- Undersized screen for reading distance. 9" at 1.5 m from helmsman = illegible in rough seas. Measure distance before purchase.
- No external GPS antenna. The combo's internal GPS is masked by the sunshade. Add an external antenna or a separate GPS-500 in cabin installs.
- Network cable run parallel to engine cables. RF noise → frozen screens. Always separate signal from power cables.
- No secondary screen offshore. Main combo failure = end of navigation. Always have a backup screen (smartphone Aquamap + Garmin GPSMAP 86s portable GPS is enough).
- Commissioning without HSD calibration (Heading/Speed/Depth). The combo is an aggregator — without upstream sensor calibration, its calculations (VMG, laylines, ETA) are false.
FAQ — Choosing a combo in practice
Does the touchscreen resist salt spray and gloves?
Yes on all 2026 recreational models (Axiom, Zeus, GPSMAP). Marine-specific capacitive touch, works with fine neoprene gloves (3 mm) and salt spray. For thick offshore gloves (5 mm + wet), use a ZC2 remote.
Can you mix Raymarine and B&G on the same boat?
Yes via standard NMEA 2000, but with compromises. AIS/GPS sharing is easy. Raymarine autopilot + B&G Zeus works but loses advanced integration (polars from Zeus to autopilot). Ecosystem consistency remains preferable.
How long does a modern combo last?
Typically 8-12 years before upgrade. Electronics age less than the touchscreen (calibration drifts after 8-10 years). 2018+ models still perform well in 2026.
Touchscreen or buttons offshore?
For quick manipulations in rough seas, physical buttons are superior. Mixed models (Axiom Pro with rotary buttons) are most appreciated in racing and long-distance cruising.
Separate depth sounder or integrated?
Integrated (Axiom, Zeus, GPSMAP) is sufficient for cruising. Dedicated separate depth sounder (B&G Halo SS35, Furuno DFF) only if big-game fishing or precise bathymetry. For 95% of recreational sailboats, integrated is fine.
3 real-world workshop cases — combo choices
Case 1 — Pogo 12.50 summer coastal family sailing
2023 model, basic equipment. Recommendation: 1 × B&G Zeus 3S 12 (~ $3,500 USD), native C-MAP chart integration and existing Triton². Total installed $4,200 USD (combo + accessories + 5 h labor). Owner feedback: "The 12-inch makes a real difference when I need to read the chart and radar simultaneously in rough seas."
Case 2 — Bénéteau First 45 IRC racing sailboat
2024 refit. 1 × B&G Zeus 3S 12 helm + 1 × Vulcan 9 R navtab. H5000 Performance CPU integration. Total combos: $5,400 USD. Choice justified by dual visualization: large chart for helmsman + detailed tactical for navigator. Spi Ouest-France 2025 regatta: "Laylines perfectly visible at both stations simultaneously."
Case 3 — Lagoon 50 Caribbean charter yacht
Setup: 2 × Zeus³S Glass Helm 16-inch + 2 × Zeus 3S 12 repeater screens. Total: ~ $13,000 USD installed. Justification: market standards for high-end charter (non-professional tenant autonomy + redundancy).
Alternatives excluded — combos not selected
- 7-inch combos (Vulcan 7, GPSMAP 723xsv): too small for navigation in conditions. Useful only as secondary in the saloon or small racing dinghies.
- Furuno combos (NavNet TZTouch): technically excellent but oriented toward commercial/fishing. Pleasure sailboat integration less refined than B&G/Raymarine. 20-30% premium.
- Lowrance HDS Live combos: very good for fishing, sailboat integration less advanced. Consider if mixed sailboat/big-game fishing ecosystem.
- Ruggedized tablets + apps (iPad + Aqua Map, etc.): secondary backup only, never primary. Lack marine robustness (IPX7 waterproofing, button ergonomics in rough seas).
Redundancy strategy — why 2 screens beat one large
On sailboats > 40 ft with substantial budget, the question "1 × 16-inch vs 2 × 12-inch" arises. Our workshop verdict:
- 2 × 12-inch preferred in 70% of cases. Reasons: hardware redundancy (1 failure = navigation possible), functional distribution (main chart + radar + AIS on 1, depth sounder + instruments + polars on 2), helm ergonomics (1 large vs 2 placed at helmsman height).
- 1 × 16-inch preferred in 30% of cases: wide flybridge with single helm station, high-end aesthetics required, existing dashboard integration.
Skysat distributes Raymarine, B&G, Garmin, and Navico. Article based on 80+ sailboat refits 2022-2026. 2026 USD prices are indicative distributor MSRP.
