Regent and the Viceroy seaglider that flies ten feet above the ocean on a cushion of ground effect

Regent, a startup based in North Kingstown, Rhode Island, is building the Viceroy—an all-electric vehicle that flies ten feet above the ocean at 180 miles per hour by exploiting ground effect, the same aerodynamic phenomenon that makes your airplane float in the flare. Instead of competing in the crowded urban air taxi market, Regent is targeting coastal city pairs with a vehicle that is classified not as an aircraft but as a maritime vessel, certified by the U.S. Coast Guard rather than the FAA.

What Is Ground Effect and Why Does It Matter for Electric Flight?

When a wing operates within roughly one wingspan length of a surface, the ground or water beneath it compresses the downwash from wingtip vortices. That compression reduces induced drag significantly. For the Viceroy, Regent claims this translates to roughly 40% more aerodynamic efficiency compared to the same wing flying at altitude.

That efficiency gain is the key to the entire business case. Batteries contain about 40 times less energy per kilogram than jet fuel. That ratio is why the Eviation Alice maxes out around 250 nautical miles and why most electric air taxis are designed for trips under 60 miles. Rather than waiting for a battery breakthrough no startup controls, Regent designed the vehicle around the batteries available today, using ground effect to stretch their range to 180 miles with up to 12 passengers.

How Does the Viceroy Actually Work?

The Viceroy operates in three distinct modes:

Mode 1 — Hull-borne. It sits on a hull in the water like a conventional boat, using hydrofoils to begin lifting out of the water and reducing drag.

Mode 2 — Foil-borne. It rises fully onto hydrofoils and accelerates like a high-speed foiling vessel.

Mode 3 — Wing-borne in ground effect. At around 40 knots, enough aerodynamic lift develops to leave the water entirely. The Viceroy then cruises 10 to 30 feet above the surface at approximately 180 mph.

Regent calls it a seaglider, and that term captures what no existing category does—it is not an airplane, not a boat, and not a hovercraft.

Have Ground Effect Vehicles Been Built Before?

Ground effect vehicles have a long and dramatic history. The Soviet Union built enormous machines called ekranoplans during the Cold War. The most famous, the Lun-class, weighed 380 tons, carried six anti-ship missiles, and flew 20 feet above the Caspian Sea. Western intelligence nicknamed it the “Caspian Sea Monster” because early satellite photos defied explanation—too large for an airplane, too fast for a ship.

The physics are well understood and have been documented in aerodynamics textbooks since the 1920s. What Regent is doing is not a fringe physics experiment. It is a modern engineering application of proven principles, packaged with electric propulsion and fly-by-wire controls.

Why Is Regent Working With the Coast Guard Instead of the FAA?

Because the Viceroy operates below the altitude threshold the FAA typically regulates and departs from marine infrastructure over water, it is classified as a maritime vessel. This puts Regent on a completely different regulatory pathway. Historically, maritime certification has been faster and more flexible than aviation certification for novel vehicle types.

This means Regent is not stuck in the same certification queue as Joby, Archer, and Lilium. The tradeoff: the Coast Guard has never certified an electric wing-in-ground-effect passenger vehicle, so the framework is being built as the process unfolds.

What Are the Real Engineering Challenges?

Ocean surface dynamics. Flying at 180 mph ten feet above waves running three to five feet high demands extremely precise flight controls. The Viceroy uses a fly-by-wire system with sensors that continuously measure surface distance and adjust control surfaces in real time. Regent states the control algorithms handle conditions up to sea state 4 (moderate seas, waves up to about eight feet). Beyond that, the vehicle remains in foil-borne mode and operates as a fast ferry.

Salt water corrosion. The airframe endures continuous saltwater spray and immersion during every takeoff and landing. Regent uses composite materials extensively, but motors, bearings, electrical connections, and battery enclosures all require sealing standards far beyond what a hangar-kept aircraft needs.

Passenger comfort. Ground effect flight over water is not the same as cruising at FL250 in smooth air. Demonstration flights in calm water look remarkably smooth, but a three-foot chop on a windy day in the Long Island Sound will produce a very different ride.

Operational envelope. This is a fair-weather, coastal-only vehicle. Winter sea states off the coast of Maine are outside the operating window. The narrow operational envelope limits revenue-generating hours per year compared to a traditional aircraft.

Where Does Regent Stand Today?

Regent flew a quarter-scale unmanned prototype in 2022 that demonstrated all three modes successfully—hull-borne, foil-borne, and transition to free flight in ground effect. Since then, the company has been building a full-scale technology demonstrator and has raised over $100 million in funding.

The order book includes commitments from several regional operators, most notably a deal with an airline operating in the Hawaiian Islands for inter-island routes, along with interest from ferry operators in the Pacific Northwest, Northeast Corridor, and Southeast Asia. Regent is targeting entry into service in 2028.

What Gives Regent an Edge Over eVTOL Competitors?

Three structural advantages stand out:

The Viceroy never hovers. Hover is the most power-intensive phase of flight for any eVTOL, requiring enormous thrust directed straight down and oversized motors and batteries. The Viceroy transitions from hull to foil to wing-borne flight, using forward speed to generate lift at every phase—dramatically more efficient.

The routes already exist. Coastal city pairs with existing ferry infrastructure are natural markets. No vertiports needed. No new travel category to create in the consumer’s mind. People already pay to cross these waterways. Regent offers to do it 5 to 10 times faster with zero direct emissions at a price point the company claims will compete with existing high-speed ferry tickets.

Different certification lane. The maritime pathway avoids direct competition for FAA certification resources that every eVTOL company is fighting over.

The competition is not absent, though. Candela, a Swedish company, is building high-speed electric hydrofoil ferries achieving 40 knots on electric power. They are slower than the Viceroy but further along in certification and solve many of the same coastal transportation problems.

What Routes Could the Viceroy Serve?

If the Viceroy performs as advertised, the impact on coastal transportation could be significant:

Boston to Provincetown — approximately 30 minutes instead of 90
Miami to Bimini — approximately 20 minutes
San Francisco to Oakland — approximately 6 minutes across the Bay
Hawaiian inter-island routes
Pacific Northwest ferry corridors

These are existing ferry corridors where passengers already pay to cross water and would pay more to do it faster.

Key Takeaways

Regent’s Viceroy exploits ground effect—flying 10–30 feet above water—to achieve roughly 40% greater aerodynamic efficiency, solving the battery density problem that limits every electric aircraft
The vehicle operates in three modes (hull, hydrofoil, wing-in-ground-effect) and is classified as a maritime vessel under Coast Guard jurisdiction, not FAA
Ground effect is proven physics, not speculation—documented since the 1920s and operationally demonstrated by Soviet ekranoplans during the Cold War
Real challenges remain: ocean surface dynamics, salt corrosion, passenger comfort in rough seas, and an uncharted certification pathway
Entry into service is targeted for 2028, with over $100 million raised and operator commitments across Hawaii, the Pacific Northwest, and the Northeast Corridor