This Hybrid Boat-Plane Flies Over The Water
The EP-15 uses ground effect to fly above the surface.
It’s a plane. It’s a boat. It’s a water-crossing, air-bound platypus of a creation that manipulates a law of physics that ocean-traversing birds have used forever to fly farther, faster and with less effort.
Officially, it’s called the EP-15, 22-metre craft with space for two crew and 10 passengers built by RDC Aqualines.
Technically, it takes advantage of something known as ground effect, which occurs in fixed-wing vehicles when they fly at an elevation less than or roughly equal to half the length of their wingspan. At that altitude, excess air pressure develops between the wing and the surface, creating additional lift and reducing downdraft.
With its 16-metre wingspan, the EP-15 could, in theory, ride up to 7-metres off the surface of the water, but the published cruising altitude is actually just over a foot. The craft will first plane like a boat, and then hydrofoil on a central “hydroski” before gaining enough speed to lift clear at roughly 110km/h.
Propulsion details are sparse so far, but RDC has said that a 600-hp electric-hydrogen hybrid powertrain will turn the three propellers—two small ones on either side of the nose and a larger, central one at the rear—and retractable winglets will enhance the aerodynamics. Performance projections give the EP-15 a top speed of approximately 200km/h, with a cruising speed of 185km/h and range of about 600km/h with a full load.
The interior is arranged like a typical aeroplane, with single rows of seats separated by a central aisle. It can also be emptied, allowing the EP-15 to function as a cargo vessel, or customized to fit individual needs. Retractable landing gear allows it to taxi up onto a hard surface at the water’s edge.
It’s expected to launch—and splash down—in 2024.