A careful synthesis of marine architecture, foil dynamics, and practical liveaboard thinking—resulting in a seastead that is stable, comfortable, efficient, and affordable.
This seastead is built around a 70-foot triangular truss frame elevated above the water on three foil-shaped legs. Each leg is 19 feet long with a NACA 0030 profile, a 10-foot chord, and a 3-foot width. They are attached near the three corners of the triangle and extend downward so the lower half sits in the water. The result is a trimaran-like platform with an exceptionally small waterplane area—combining the gentleness of a semi-submersible with the mobility of a foil-assisted vessel.
What follows is a breakdown of why every design choice reinforces the others, creating a whole that genuinely excels—even before considering the optional extras.
The three legs are placed at the extreme corners of the 70×35 ft triangular frame. This creates an enormous base of buoyancy relative to the vessel's footprint. Because the legs are far apart, the righting moment is exceptionally high—the seastead resists heeling with tremendous leverage.
There is no realistic danger of capsizing. Even in severe conditions, the geometry ensures that as one leg is lifted by a wave, the other two legs—spread wide—provide a counteracting buoyant force that brings the platform back to level. The platform simply does not want to turn over.
Traditional boats have a large waterplane area—the cross-section where the hull meets the water surface. This means every passing wave displaces a large volume of water and jostles the vessel. By contrast, this seastead's three foil-shaped legs slice through the water surface with a minimal footprint.
The result is that small and medium waves pass by with very little response. The seastead effectively "ignores" chop and swell that would have a conventional monohull or catamaran pitching and rolling. This is the same principle used by semi-submersible oil platforms—but implemented in a lightweight, mobile package.
A potential concern with very small waterplane area is behavior in large seas. This design addresses that concern elegantly: while small waves are largely ignored, large waves are met with sufficient buoyancy reserve in the foil-shaped legs. As a big wave approaches, the legs—with their 10-foot chord and 3-foot width—displace enough water to lift the platform gently up the face of the wave.
The seastead rides up and over large swells rather than punching through them. The 50% submergence of each leg (about 9.5 feet underwater in calm conditions) provides ample reserve buoyancy for this behavior. The platform stays on top of the ocean rather than fighting it.
Unlike a conventional semi-submersible platform—which is essentially stationary—this seastead's legs are shaped as symmetric airfoils (NACA 0030) with the blunt leading edge facing forward. This dramatically reduces hydrodynamic drag when underway.
The three legs all run parallel with the direction of travel, so the water flows smoothly around their foil profiles. Six RIM drive thrusters (1.5-foot diameter, one on each side of each leg, positioned about 3 feet up from the bottom) provide propulsion with minimal external appendages. RIM drives—where the blades are housed within a ring—are inherently efficient and protected.
Additionally, the foil-shaped legs function as daggerboards, providing lateral resistance that makes kite sailing practical. For storm avoidance, a drogue deployed on a harness provides directional control while running with the weather.
By placing buoyancy only at the three corners—rather than across an entire hull—the total structural weight can be dramatically reduced. The triangular truss frame is inherently stiff and material-efficient, and the legs are compact, foil-shaped structures rather than sprawling hulls.
This seastead can be far lighter than a typical 70-foot vessel of comparable living space. And in marine construction, cost scales closely with weight—less material, fewer labor hours, smaller lifting equipment, and reduced transport expenses all flow from a lighter design.
The entire roof of the triangular living area—roughly 70×35 feet of surface—is covered in solar panels. Because the structure is so lightweight relative to its size, the ratio of solar collection area to vessel weight is outstanding.
Furthermore, batteries are placed at the bottom of the legs, serving a dual purpose: they provide energy storage while simultaneously lowering the center of gravity and increasing rotational inertia. This improves both static stability and damping—the platform resists being set into oscillation by waves.
Three stabilizers—shaped like small airplanes—are attached near the back of each main leg. Each stabilizer has a 12-foot wingspan, a 1.5-foot chord, a 6-foot body, and an elevator with a 2-foot span and 6-inch chord.
The genius is in the actuation: instead of moving the entire wing (which would require a large, expensive actuator), a small actuator angles the elevator up or down. This changes the angle of attack of the main stabilizer wing without needing to pivot the whole surface. The pivot is balanced so the center of lift aligns with the attachment point—requiring only a notch of about 25% of the chord into the front/center of the wing.
Because these stabilizers are positioned at the edges of the platform and the waterplane area is small, they have excellent leverage to counteract roll and pitch. The result is active stabilization at a fraction of the cost of conventional fin stabilizer systems.
When the seastead is staying in one place for an extended period, three helical mooring screws are deployed into the seabed, and the platform is secured with tension legs. Because there are exactly three legs on the seastead and three mooring points, the geometry is naturally compatible.
With tension leg anchoring, the platform becomes nearly stationary—vertically and horizontally constrained. This provides an incredibly stable working environment, making it easy for digital nomads to focus on their work without the distraction of movement. It's the seastead equivalent of being on solid ground.
The NACA 0030 foil legs serve double duty as effective daggerboards, providing the lateral resistance needed for kite sailing. A large traction kite can be deployed to harness wind power for efficient, low-energy transit when conditions are favorable.
In storm conditions, when the safest strategy is to run with the weather, a drogue can be deployed on a harness system. The foil legs provide directional stability, and the drogue keeps the platform oriented correctly relative to the waves. This combination gives the seastead genuine storm-survival capability without requiring massive engine power.
Several factors converge to make this seastead remarkably cost-effective for its size:
The overall philosophy is smart simplicity—every component serves multiple purposes, and nothing is overbuilt beyond what the design actually needs.
The design considers the human experience at every level:
This seastead is not a collection of independent features—it is a tightly integrated system where each element reinforces the others. The wide-set foil legs provide stability and mobility and anchoring compatibility. The light weight enables excellent solar performance and low cost and a soft ride. The stabilizers leverage the small waterplane area for maximum effectiveness with minimal actuation force. The foil shape serves propulsion efficiency, kite sailing, and storm-running simultaneously.
And all of this is achieved before considering the optional extras—which layer additional capability onto an already solid foundation.
In short: this design is stable without being sluggish, comfortable without being fragile, mobile without being fuel-hungry, and affordable without cutting corners. That is why it works so well.