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Estimated Circumnavigation Time (Solar + Kite Seastead)
Estimated Travel Time to Circumnavigate the Earth
for a Solar + Kite Powered Seastead
Result (order-of-magnitude):
- Underway (“moving”) time: ~9–11 months (typical ~10 months)
- Plus waiting for seasonal cyclone avoidance / monsoon windows: ~2–4 months
- Total elapsed time: ~12–15 months (optimistic ~11 months, conservative ~18+ months in a bad-weather year)
These estimates assume you can route-optimize continuously using forecasts (winds + surface currents + eddies), and you avoid the Roaring Forties/Furious Fifties as requested (targeting seas generally < 15 ft by waiting when needed).
Given Propulsion Modes (Speed Relative to Water)
- Kite mode: 3 mph (≈ 2.6 kn) but only when traveling within 30° of downwind.
- Solar high sun: 2 mph (≈ 1.74 kn) for 6 hours/day.
- Solar/battery: 1 mph (≈ 0.87 kn) for 18 hours/day.
How the estimate uses those modes
- In the trade-wind belts and along “downwind corridors,” assume you can use kite mode ~70–85% of the time (day and night), because you can steer a route that keeps your desired course broadly downwind most of the time.
- When not able to remain sufficiently downwind (routing constraints, doldrums, coastal effects, convergences), you fall back to solar/battery.
- Solar-only average over 24h (if no kite) is:
(6h×1.74 kn + 18h×0.87 kn)/24h ≈ 1.09 kn.
Ocean Assistance Assumptions (Currents + Eddies)
- In favorable regions (North/South Equatorial Currents, Indonesian Throughflow, parts of Agulhas/Mozambique Channel, Canary Current, etc.), sustained surface currents of ~0.5–1.5 kn are common.
- Eddies can briefly give more, but because they’re patchy and time-limited, this estimate uses a conservative “route-optimized average assist” of:
- ~0.8–1.0 kn on the big trade-wind westbound crossings,
- ~0.3–0.7 kn in more constrained seas (Red Sea / Mediterranean routing, or where winds oppose).
Recommended Low-Latitude Route (Avoiding Roaring Forties)
To avoid spending “too much time” in the Roaring Forties/Furious Fifties, the best practical circumnavigation is to use a canal rather than rounding Cape Horn, and preferably avoid the roughest part of the Southern Ocean.
The lowest-latitude, most current/wind-assisted strategy is generally:
- Go westbound in the trades across the Pacific and Indian Oceans.
- Use the Suez Canal (rather than the Cape of Good Hope) to avoid sustained Southern Ocean exposure.
- Return westbound across the tropical Atlantic back to the Caribbean region (completing the loop).
Important feasibility note: This assumes canal transit is allowed for your craft (size, tow requirements, fees, regulations).
If canals are not allowed, the Cape of Good Hope route is the next option but tends to increase waiting for <15 ft seas.
Estimated Time by Route Segment (Suez-based, trade-wind optimized)
| Leg (typical waypoints) |
Why it’s favorable |
Approx. distance (nm) |
Estimated avg. speed over ground (kn) |
Moving time (days) |
1) Pacific westbound
Panama region → Galápagos vicinity → Marquesas/Tuamotus → Samoa/Fiji → Solomons → Indonesia |
Trade winds + South Equatorial Current (westbound). Lots of room to “stay downwind,” route around doldrums, and cherry-pick eddies.
|
~8,500–9,200 |
~3.0–3.6
(2.6 kn kite often + ~0.8–1.0 kn current assist) |
~100–125 |
2) Indian Ocean westbound
Indonesia (e.g., Lombok/Sunda exit) → Cocos/Chagos latitude band → Seychelles/Madagascar latitude band → toward Gulf of Aden |
Seasonal trade/monsoon windows + South Equatorial Current (westbound). Requires timing to avoid opposing monsoon periods and cyclone season.
|
~4,500–5,200 |
~2.8–3.4 |
~55–77 |
3) Red Sea + Suez + Mediterranean
Bab-el-Mandeb → Suez → Med → Gibraltar |
More constrained. Winds can be channelled and sometimes opposing; current help is smaller than open-ocean equatorial flows.
You rely more often on solar/battery segments, and may wait for calmer seas.
|
~3,000–3,500 |
~2.0–2.6 |
~48–73 |
4) Tropical Atlantic westbound
Gibraltar/Canaries latitude band → Cape Verde latitude band → Caribbean → back to start region |
Northeast trades + North Equatorial Current (westbound). One of the most consistently favorable “downwind + downcurrent” corridors.
|
~3,800–4,600 |
~3.0–3.7 |
~45–65 |
| Subtotal (underway) |
~20,000–22,500 nm |
— |
~250–340 days |
Waiting Time to Avoid Cyclones / Bad Seasonal Windows
You asked to assume it keeps moving unless it needs to wait until a hurricane/cyclone season passes.
On a low-latitude circumnavigation, the main schedule risks are:
- Atlantic hurricanes (roughly Jun–Nov; peak Aug–Oct)
- Eastern/Central Pacific hurricanes (roughly May–Nov; peak Aug–Oct)
- Indian Ocean cyclones (South Indian: roughly Nov–Apr; North Indian: Apr–Jun and Oct–Dec)
- Monsoon reversals (particularly impacting the Arabian Sea / approach to Red Sea)
With active routing and a willingness to pause, a realistic planning number is:
- Typical waiting: ~60–120 days
- Good year / well-timed departure: ~30–60 days
- Bad year (or strict <15 ft rule): ~120–240 days
Bottom-Line Estimates
| Scenario |
Underway time |
Waiting time |
Total elapsed |
| Optimistic (excellent timing, favorable trades, minimal pauses) |
~250–285 days (8–9.5 months) |
~30–60 days (1–2 months) |
~9–11 months |
| Typical (practical routing + a couple of seasonal holds) |
~285–320 days (9.5–10.5 months) |
~60–120 days (2–4 months) |
~12–15 months |
| Conservative (strict <15 ft seas, worse timing, more doldrums/monsoon conflict) |
~320–340 days (10.5–11+ months) |
~120–240 days (4–8 months) |
~15–20+ months |
Alternative: “No-Canal” Route (Cape of Good Hope)
If Suez (and Panama) are not options, you would likely still cross westbound in the trades, then eventually round the Cape of Good Hope.
You can try to keep latitude modest (often ~30–38°S) to avoid the worst of the Roaring Forties, but sea state around the Cape can still violate a “generally under 15 ft” preference, increasing waiting.
- Underway time: often similar on paper (~9–11 months moving)
- Waiting time: typically higher (more weather-window dependence), often pushing totals toward 14–18+ months
What Would Improve This Estimate
If you want, I can tighten the numbers if you specify:
- Start/finish location (single port/anchorage) and whether Panama/Suez are allowed.
- How often kite mode is possible in practice (e.g., “assume kite usable 60% / 75% / 90% of the time when offshore”).
- Your maximum acceptable sea state more precisely (significant wave height in meters/feet), and whether you’ll heave-to vs. drift vs. “push through.”
- Whether you will accept occasional short high-latitude dips (e.g., 35–42°) to pick up stronger currents/westerlies.
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