Below is a complete, self-contained HTML page with the full analysis — design feedback, packing math, weights, performance table, costs, pricing, and the battery-shipping question. All figures are rough-order-of-magnitude (±30–50%) planning estimates, not engineering sign-off.
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Minimal Viable Seastead — Feasibility, Packing, Cost & Pricing Study
Minimal Viable Seastead — Feasibility, Packing, Cost & Pricing Study
Rough-order-of-magnitude (ROM) planning study. All engineering numbers are pre-naval-architect estimates (±30–50%). All costs are 2024–2025 USD ballparks. This is a decision-support document, not a design approval.
1. Executive summary
- The concept is buildable. Frustum hulls are trivially manufacturable (rolled plate), the parts commonality is excellent (4 identical hull sections, 4 identical caps, 4 identical beams — only ~4 unique structural parts), and everything fits in its own 40'HC container with ~1–3 ft of length margin.
- Nested hull stack length ≈ 36.5–38.5 ft vs. 39.5 ft interior — it fits, but tight. Recommend 32-ft sections for margin.
- Battery answer: 2 days of solar ≈ 120 kWh ≈ 2,200 lb total, ≈ 550 lb per bank (4 banks), best built from 4–6 carryable modules per bank.
- Loaded displacement ≈ 34,000 lb (15.5 t) against ~40 t max hull buoyancy — ~40% submerged, huge reserve. Good.
- Performance: ~4–5 knots continuous on solar alone; ~9 kn for 5 h on batteries; most inter-island hops are same-day.
- Naval architect program (China): ≈ $250k–$550k all-in.
- Unit cost (parts + shipping + assembly): prototype ≈ $460k; batch of 20 ≈ $300k; batch of 50 ≈ $255k; batch of 200 ≈ $215k.
- Suggested retail after the first 20: $399k–$449k assembled in the Caribbean; $229k–$259k FOB China as a kit.
- LFP batteries CAN ship in the kit container (UN3480, Class 9) with a DG-experienced forwarder and a carrier that accepts lithium; have a Florida-sourced Plan B.
2. Design feedback
2.1 What is genuinely good about this concept
- Container corners ↔ beam/cable load points: real synergy, as you noted. ISO corner castings are rated for lifting 30 t; your loaded house is ~15–16 t spread over 4 corners. Have the NA add doubler plates at the corner castings since your loads include uplift/lateral components, not just vertical lift.
- Parts commonality: 4 identical frustums + 4 identical caps + (ideally) 4 identical beams. This is excellent for robot welding, spares, and cost — a bigger economic advantage than it first appears.
- 4 watertight compartments from the bolted flange + plate joint: genuinely good damage tolerance; also gives you a natural structural node for beam/walkway attachments.
- Slender hulls (L/B ≈ 14): low wave-making; the solar-electric speed budget (below) is realistic.
- Wharram-style compliance: controlled flexibility avoids stress concentrations — but aluminum is unforgiving of fatigue, so every cable terminal, flange, and weld toe must be designed for inspectability and replacement, with generous radii.
- On-water final assembly: clever cost saver; the cable-tensioning lifting procedure is plausible but must be engineered (see NA scope item 4) and rehearsed with the scale model.
2.2 Issues to resolve (feed these to the naval architect)
| # | Issue | Recommendation |
|---|
| 1 | Thruster vs. pointy stern conflict. Large, slow props (correct instinct for efficiency) don't fit on a 2-ft-diameter pointed tail. | Mount pods/saildrives under the hull ~12–18 ft forward of the stern where the cone is ~3.5–4 ft diameter, or use steerable pods. Keep rudders or fixed fins for redundancy — differential-thrust-only steering with one dead motor is a real failure mode. |
| 2 | 10 mm (1 cm) plate is probably over-spec. A stiff conical shell in 5083-H116 typically needs 5–8 mm. | Let the NA run ISO 12215 scantlings. Dropping to 6–8 mm saves ~1.5 t and ~$15–25k/unit. |
| 3 | Galvanic chain: Al hulls + SS bolts + steel ISO corners + possibly bronze thru-hulls. | Isolating sleeves + Duralac on every SS fastener; bolt-on (not welded) steel corners, isolated, or remove post-shipping; aluminum-alloy anodes; bonding/isolation monitoring per ABYC E-11. |
| 4 | Bolted flange joint fatigue & sealing. | EPDM/neoprene gaskets both faces as you planned; serrated-flange bolts; torque + re-torque after launch; design so bolts stay in tension, plates in compression. Make it the attachment node for beams/walkway. |
| 5 | Battery compartment geometry. 550 lb bank won't fit as one unit into a 2-ft-diameter tail. | Specify 4–6 slim modules (~60 kg each) per bank passed through the hatch; or locate banks where hull Ø ≥ 3.5 ft. Ventilate per ABYC E-13; watertight (IP67+) hatches — these are also your downflooding points. |
| 6 | Windage / hobby-horsing. High box, low ballast — pitch inertia from end-mounted batteries lowers the natural frequency (usually helpful), and active thrust modulation can damp resonance, but it's a control system, not a bolt-on. | Scale-model test it; treat active damping as a stretch goal. Fixed fins/daggerboards per hull are definitely needed for crosswinds (your instinct is correct — side windage area is large). |
| 7 | Solar overhangs (3 ft each side). | Design hinges or quick-release for storm removal; wind-uplift analysis at 60+ kn. |
| 8 | Interior is narrow (7.7 ft). Wider than many sailboat cabins, tighter than any production catamaran salon. | Honest marketing: cozy for a couple, fine for the niche. Consider a deck awning/tent as standard kit to expand living space. |
| 9 | Air bags vs. foam. Removable air bags work but can chafe and trap moisture against aluminum (crevice corrosion). | Consider closed-cell foam blocks shaped to the cone — zero maintenance, still removable for inspection. |
| 10 | Regulatory. LOA with 5-ft caps ≈ 76 ft = 23.2 m ✓ under 24 m — keep it there. Panama pleasure registration is easy; insurance for a novel craft is the harder gate. | Budget for survey-based agreed-value insurance; the ISO 12217 stability booklet + class-like structural report (NA scope item 5) is what unlocks insurance and port entry. |
3. Container packing & "stacked like cups" geometry
3.1 Nesting math (4 hull sections as cups)
| Parameter | Value |
|---|
| Section geometry | Frustum, 33 ft long, Ø 2 ft → 5 ft |
| Radius growth along axis | 1.5 ft ÷ 33 ft = 0.545 in per ft (radius), 1.09 in/ft diameter |
| Radial space needed per nesting level | Wall 0.394 in + clearance 0.25–0.6 in ≈ 0.65–1.0 in |
| Added length per nested section | 0.65–1.0 in ÷ 0.545 in/ft = 1.2–1.8 ft |
| Total nested stack, 4 sections | 33 + 3×(1.2–1.8) = 36.5–38.5 ft |
| 40'HC interior length | 39.46 ft (12.03 m) |
| Verdict | Fits with 1–3 ft margin — tight. Recommend 32-ft sections (nested ≈ 35.5–37.5 ft) for comfortable margin. |
| Stack max diameter incl. flanges | 5 ft shell + ~6 in flange ring each side ≈ 6.0 ft vs. 7.7 ft interior width ✓ (flanges sit at different axial stations, no interference) |
| Nested pointy caps (4 × 5-ft cones, Ø 2 ft base) | ≈ 5.8 ft long, 2 ft OD → fit inside the innermost section's large end (ID ≈ 4.8 ft) ✓ |
3.2 Packing plan for everything else
| Item | Approx. size / weight | Placement |
|---|
| Hull section nest | ~37 ft × 6 ft Ø; ~9,300 lb | Along one wall, large (flange) end toward doors for unloading |
| Cap nest | ~6 ft × 2 ft Ø; ~260 lb | Inside hull nest, or beside the narrow end |
| 4 beams | Real geometry gives ~17–22 ft each (container top corner ≈16 ft above water, ~5.5 ft horizontal offset to hull centerline) — far under your 40-ft limit; ~3,100 lb total | Beside the tapering nest (clearance is 5.7 ft at the small end, 2.7 ft at the large end) or above the nest (≈3 ft of headroom) |
| Solar panels, ~26 × 440 W | 2 pallets, each 7.5 × 3.8 × 2.7 ft; ~1,600 lb | Beside the narrow half of the cone nest |
| Batteries (see LFP section) | 16–24 modules; ~2,200 lb | Floor, secured per IMO CTU Code |
| Thrusters, tanks, anchor, hatches, interior kit, cables, walkway grating, ladders | ~3,000 lb, palletized/crated | Door-end bay + voids |
| Total payload | ≈ 19,000 lb (8.6 t) | vs. 40'HC payload limit ≈ 63,000 lb (28.6 t) — 30% utilized; weight is not a constraint, 3D packing is. Commission a formal packing plan from the 3PL. |
4. Weight budget & battery answer
| Item | kg | lb |
|---|
| Custom aluminum 40'HC container shell (with bolt-on/isolated steel ISO corners, CSC plated) | 2,500 | 5,500 |
| Interior fit-out (insulation, galley, head, HVAC, wiring, plumbing, windows/doors) | 2,500 | 5,500 |
| 4 hull sections @ ~1,050 kg (10 mm 5083 shell + end cap + flange + stiffeners) | 4,200 | 9,260 |
| 2 joint plates + gaskets + fasteners | 140 | 310 |
| 4 pointy caps | 120 | 265 |
| 4 beams (~350 kg each) | 1,400 | 3,090 |
| Cables, terminals, winches, ladders, walkway, railings | 480 | 1,060 |
| Solar array 11.5 kWp + frames, MPPTs, cabling | 820 | 1,810 |
| Batteries: 120 kWh LFP | 1,000 | 2,205 |
| 2 × 15 kW thrusters + props | 160 | 350 |
| Tanks (empty), anchor/windlass, foam, anodes, misc. | 1,000 | 2,200 |
| Water (200 gal) + waste + stores + crew | 1,400 | 3,090 |
| Loaded displacement | ≈ 15,700 | ≈ 34,600 |
|---|
| Max hull buoyancy (2 hulls × 19.4 m³ seawater) | ≈ 39,700 | ≈ 87,500 |
| Submergence at full load | ≈ 40% → hull draft ≈ 2 ft; ~2.3× reserve buoyancy ✓ |
Question 7 answer — battery weight:
Solar array ≈ 11.5 kWp × ~5.2 peak-sun-hours (Caribbean, horizontal panels) ≈ 60 kWh/day → 2 days = ≈ 120 kWh nominal.
Marine LFP packs run ~110–130 Wh/kg → total ≈ 960–1,090 kg ≈ 2,100–2,400 lb; call it ≈ 2,200 lb (1,000 kg).
Each of the 4 banks ≈ 250 kg ≈ 550 lb, best packaged as 4–6 modules of ~60 kg (27 × 16 × 10 in each) so two people can pass them through the hull hatches. Usable energy ≈ 108 kWh at 90% depth of discharge.
Assumptions: calm water, clean hull, loaded 15.5 t, wetted surface ≈ 56 m², propulsive efficiency ≈ 55% (large slow props), 2 × 15 kW motors (30 kW max), 120 kWh battery (108 kWh usable), 11.5 kWp array yielding ≈ 60 kWh/day, hotel load ≈ 17 kWh/day with A/C and ≈ 4 kWh/day without. Add 20–30% margin for real seas/currents/headwinds.
| Speed (kn) | Electrical power (kW) | Speed (kn) | Electrical power (kW) |
|---|
| 3 | 0.6 | 7 | 8.0 |
| 4 | 1.4 | 8 | 12.5 |
| 5 | 2.7 | 9 | 18.5 |
| 6 | 4.7 | 10 | 27 (≈ motor limit) |
| # | Scenario | Propulsion power available | Speed | Distance |
|---|
| 1 | Typical Caribbean sun, 24/7 continuous, A/C on (day solar + night battery) | (60 − 17) ÷ 24 h ≈ 1.8 kW avg | ≈ 4.2 kn | ≈ 100 nm/day, indefinitely |
| 2 | Same, all A/C off | (60 − 4) ÷ 24 h ≈ 2.3 kW avg | ≈ 4.7 kn | ≈ 113 nm/day, indefinitely |
| 3 | Full batteries, drained over 5 h, no sun | 108 ÷ 5 ≈ 21.6 kW | ≈ 9.3 kn | ≈ 46 nm |
| 4 | Full batteries, drained over 10 h, no sun | 108 ÷ 10 ≈ 10.8 kW | ≈ 7.8 kn | ≈ 78 nm |
| 5 | Full batteries, 10:00 clear sky, solar + battery for 4 h, no A/C | Solar ≈ 8.4 kW avg + battery → demand exceeds 30 kW motor limit → capped at 30 kW | ≈ 10 kn | ≈ 40 nm, ending with ~20% battery remaining |
Context: SXM→St. Barts ≈ 17 nm, SXM→Anguilla ≈ 8 nm, Antigua→Barbuda ≈ 30 nm, Guadeloupe→Dominica ≈ 45 nm — i.e., essentially every inter-island hop is a comfortable daylight run under scenarios 3–5, and scenario 1–2 covers passages between island groups. Hull-speed/wave-making limits make sustained speeds above ~10 kn uneconomic — 2×15 kW motors are well matched; going to 2×20 kW buys only ~0.5 kn.
6. Chinese naval-architect firm — scope & cost estimates
| # | Scope item | ROM cost (USD) | Notes |
|---|
| 1 | Feasibility / design review + build-cost estimate | $20k–$50k (mid $30k) | 2 engineers, 4–6 weeks. Firms: yacht/commercial design offices in Shanghai, Zhuhai, Xiamen; or SDARI-adjacent SMEs. |
| 2 | Basic design: full engineering & structural analysis (ISO 12215 scantlings, fatigue at flanges/cable nodes, beam buckling, stability per ISO 12217) | $80k–$150k | Team of 3–4 for ~3–4 months. Includes lines plan finalization (cap shape, section length, LOA < 24 m). |
| 3 | Detailed production design: CNC cutting files, robotic MIG weld procedures (5083/5356), nesting, jigs | $80k–$180k | Chinese yards routinely robot-weld aluminum; this package is what makes batch pricing fall. |
| 4 | Formal assembly-sequence engineering (on-water erection, cable tensioning/lifting procedure, winch plan, tolerances) | $20k–$40k | Cheap insurance — this is your most novel operation; also produce the video storyboard here. |
| 5 | Compliance paperwork package | $40k–$120k | Panama flag docs (via a Recognized Organization), CSC design-type approval for the custom container (BV/LR container services in China, a few $k), battery shipping docs (UN38.3 summaries come from the pack vendor), stability booklet, structural & electrical reports, ABYC E-11/E-13-style checklists, ISO 12215/12217 reports, class-like documentation (optional CCS plan approval +$20k–$60k). This package is what unlocks insurance, port entry, and registry. |
| 6 | Third-party QC of factory output | $5k–$15k per production run | Yes — this exists as a standard service: SGS, Bureau Veritas, TÜV, or CCS surveyors do stage inspections (fit-up, weld NDT, coating, dimensional) at ~$500–$1,000/inspector-day. |
| 7 | Total | ≈ $250k–$550k (mid ≈ $350k) | One-time program cost; amortized over 200 units ≈ $1.3k–$2.8k/unit. |
|---|
7. China manufacturing cost — parts kit per unit, by batch size
| Item | Prototype (1) | Batch of 20 | Batch of 50 | Batch of 200 |
|---|
| Custom aluminum 40'HC container + isolated steel corners + CSC | $45k | $30k | $25k | $20k |
| 4 hull sections + 4 caps + flanges + joint plates (~4.5 t welded 5083) | $120k | $70k | $55k | $45k |
| 4 beams + cables, terminals, walkway, ladders, railings | $45k | $27k | $22k | $18k |
| Solar 11.5 kWp (panels are ~$2–3k of this) + frames + MPPTs + wiring | $12k | $10k | $9k | $8k |
| 120 kWh marine LFP packs w/ UN38.3 ($150–250/kWh) | $30k | $24k | $20k | $18k |
| 2 × 15 kW electric thrusters + large props | $20k | $16k | $14k | $12k |
| Interior fit-out (insulation, HVAC, galley, head, plumbing, electrical) | $55k | $38k | $32k | $27k |
| Marine windows, doors, hatches (incl. hull battery hatches) | $15k | $12k | $10k | $9k |
| Tanks, anchor gear, foam flotation, anodes, misc. hardware | $18k | $14k | $12k | $10k |
| 3PL consolidation, packing plan, container loading | $6k | $5k | $4k | $4k |
| Total parts, ex-works China (ROM ±30%) | ≈ $365k | ≈ $245k | ≈ $205k | ≈ $170k |
|---|
Prototype is high because every jig, forming die, and weld procedure is one-off; the fall from 1 → 20 is mostly amortizing setup. Below 6–8 mm plating (if the NA allows), subtract ~$10–20k at volume.
8. 3PL, shipping, and St. Maarten assembly
8.1 China 3PL
- Plenty of options (Shenzhen/Dongguan/Ningbo). Costs: storage ~$15–25/pallet/month; container loading $300–$800; DG (battery) documentation service $150–$300 per shipment; trucking to port $400–$800. Choose one with a Class-9 DG license, or consolidate batteries separately.
- Cheaper than your own St. Maarten warehouse — correct. SXM is duty-free, so import friction is low; use it as the assembly/showroom hub, not as a parts warehouse.
8.2 Shipping China → Philipsburg, St. Maarten
- The kit ships as a SOC (shipper-owned container) — the container is the cargo. With a valid CSC plate this is routine.
- Ocean freight 40'HC China→Caribbean (transshipment via Panama/Kingston/Caucedo): $4k–$8k; + port handling both ends $1.5k–$3k; + cargo insurance ~0.3% of value. Budget $8k–$12k per unit landed. This is your structural cost advantage over European/South African yacht builders (their delivery runs $20k–$60k).
8.3 Assembly in Dutch St. Maarten
| Phase | Duration | Notes |
|---|
| Unpack, inspect, stage | 2–3 days | Follow the video manual |
| Bolt hull halves (flange/gasket/plate), attach caps, launch hulls | 4–5 days | Crane/travelift 2–3 days, $5k–$10k |
| Float container, set beams, tension cables (iterative lift procedure), final cable lock-off | 4–6 days | The engineered assembly sequence (NA item 4); re-torque after 48 h |
| Batteries, thrusters, solar array, systems, commissioning | 5–10 days | Can be owner-completed afloat — big cost saver |
| Total | 3–4 weeks experienced crew of 3–4 (prototype: 6–8 weeks) | Labor ~$50–90/h marine trades in SXM |
Assembly cost: prototype ≈ $65k–$100k (learning curve, yard days, crane); production units ≈ $35k–$50k (≈600–700 labor-hours + crane + minimal yard space, since final work happens on the water).
9. Total program cost summary
| Component | Prototype | Batch 20 (per unit) | Batch 50 | Batch 200 |
|---|
| Parts kit (ex-works) | $365k | $245k | $205k | $170k |
| Shipping China→SXM | $10k | $10k | $10k | $9k |
| Assembly in SXM | $85k | $45k | $40k | $35k |
| Unit cost in the water | ≈ $460k | ≈ $300k | ≈ $255k | ≈ $215k |
|---|
| NA program (one-time) | ≈ $350k (prototype program total ≈ $810k including NA fees) |
10. Recommended selling price (after the first 20)
| Offer | Suggested price | Basis |
|---|
| Fully assembled, in the water, Caribbean | $399k–$449k (launch promo $375k) | ~$255k cost at 50-unit scale → 35–40% gross margin; below normal yacht markup, healthy for a startup with support obligations |
| Kit, FOB China (customer arranges freight + local assembly) | $229k–$259k | ~$170–205k cost; customer's freight + assembly ≈ $50–60k → customer all-in ≈ $310–340k |
10.1 Competitive comparison (Caribbean delivery)
| Boat | Approx. price delivered | Interior living space | vs. your seastead |
|---|
| New Lagoon 40 / Bali 4.2 (France) | $550k–$650k incl. $20–50k delivery | ~400–500 ft² | You undercut by ~$150–200k; they win on interior width, finish, brand, resale |
| New Leopard 42 (South Africa) | $650k–$750k | ~500 ft² | As above |
| 8–12 yr old 40-ft production cat | $300k–$450k | ~400 ft² | Your real competitor. You win on new systems, zero rig/diesel maintenance, stability at anchor, solar capacity (11.5 kW is 3–4× typical); they win on space and sailing ability |
| New hybrid trawler (e.g., Greenline class) | $500k+ | ~300 ft² | Similar space, you win on price + shallow draft |
| Houseboats | $150k–$300k | 400+ ft² | Cheaper but cannot relocate across open ocean — different product |
| Your seastead | $399–449k assembled / $310–340k kit all-in | ~320 ft² interior + deck | Niche: tech-nomads & older couples wanting a stable, no-sailing-skills, no-diesel, moveable island home with Starlink and huge solar |
Honest weaknesses to plan marketing around: 8-ft-wide interior, novel-craft insurance/resale, and the tension-structure launch handling (marinas/travelifts can't haul you like a normal boat — you must design a disassembly or ramp procedure for haul-outs, or plan for diver-based maintenance + sacrificial anodes).
11. Can the LFP batteries ship inside the kit container?
Verdict: Yes, it's manageable — the other AI's concern is overblown, but you must do the paperwork properly and pre-clear the carrier.
- The container question: carriers care that a SOC has a valid CSC plate and is sound — they do not require it to be a standard cargo-box shape. Your custom container with a CSC plate (allowable stacking weight may be zero — fine) will be accepted as SOC by most lines.
- The battery question is the real one: standalone LFP packs ship as UN3480, Class 9 dangerous goods under the IMDG Code. Requirements: UN38.3 test summaries (your catalog marine packs already have these — collect the actual test-summary documents, mandatory since 2020), MSDS, DG declaration, SOC ≤ 30% (most carriers now require this for UN3480), protected terminals, strong packaging, and securing per the IMO CTU Code inside the container.
- Carrier vetting: acceptance of lithium batteries is carrier- and route-specific and has tightened. Get written DG acceptance from the line (or its agent) before booking; expect to try 2–3 carriers; some will require on-deck stowage or limit quantities. A DG-experienced freight forwarder earns their fee here.
- Plan B (cheap insurance): buy the same catalog marine LFP packs from a US/Florida distributor and deliver them to the St. Maarten assembly yard separately; or have the 3PL ship them as a standalone DG consignment. Batteries are the one line item with a liquid global supply chain — don't let them gate your kit.
- Note: batteries installed and wired in equipment (UN3481) is sometimes easier — but your hull sections are arguably not "equipment" until assembled, so plan on the UN3480 path.
12. Top risks & suggested next steps
| Risk | Mitigation |
|---|
| Fatigue cracking at flange joints / cable terminals (aluminum) | NA fatigue analysis; generous radii; inspectable/replaceable terminals; strain-gauge sea trials (already in your plan ✓) |
| Insurance refusal for a novel craft | Engage a marine insurance broker + surveyor during NA phase 2, not after; the class-like documentation package exists for this reason |
| Assembly sequence surprises (first on-water erection) | Full-scale rehearsal of the cable-lift procedure at the prototype yard; NA item 4; video everything |
| DG shipping delays on batteries | Plan B sourcing (Section 11) |
| Interior too narrow for market | Deck awning standard; market honesty; consider a 45-ft HC variant later (+interior length, still standard freight) |
| Hurricane exposure despite seasonal migration | Storm-mode procedures: panel removal, mooring spec, squall handling; design wind speed ≥ 60 kn at anchor |
Comments on your preliminary plan
- 1:10 Froude scale model (7.4-ft hulls, prints in sections): speed scale = √0.1 ≈ 0.32. Test parts-fit, wave response, and cable-failure redundancy — excellent, cheap plan. Add a hobby-horsing test with end-masses in vs. out.
- Crowdfund-by-deposit after a proven prototype is the right sequencing. Take deposits sized to the batch (e.g., 40–50% on a 20-unit batch) and keep the NA+prototype budget (~$800k) as your true at-risk capital.
- Assembly videos/manuals on the website — exactly right; it converts the kit from "impossible project" to "quoted job" for any local shipyard, and doubles as owner-maintenance documentation.
- One addition: before spending NA money, spend ~$5k on a packing-plan CAD study (Section 3 geometry) — it's the cheapest hard go/no-go in the whole program.
Disclaimer: All engineering figures are pre-design estimates for planning only and must be validated by a qualified naval architect. All costs are ROM (±30–50%), USD, 2024–2025. Freight, lithium-battery, and flag-state rules change; verify at order time.
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**A few highlights worth your attention:**
- **The cup-stack works**: 36.5–38.5 ft nested vs. 39.5 ft interior — but it's tight enough that I'd go to 32-ft sections and let the caps grow (which you already anticipated).
- **One geometry catch you may not have seen**: your beams only need to be **~17–22 ft**, not "less than 40 ft" — the container roof is ~16 ft above water with only ~5.5 ft of horizontal offset to the hull centerlines. Good news for packing.
- **The pointy stern and large slow props conflict** — plan to mount thrusters as pods under the hull forward of the tail where the cone is fatter.
- **Battery answer**: ~2,200 lb total, ~550 lb per bank, and each bank should be 4–6 carryable ~60-lb modules, or they won't physically fit into the tapering hull ends.
- **The LFP shipping concern is real but solvable** (UN3480/Class 9 paperwork + carrier pre-approval), with Florida sourcing as a cheap Plan B.