The Future of Advanced Air Mobility

Japan Airlines Backs Plans for Electric Wing-in-Ground-Effect Sea Gliders

Japan Airlines (JAL) is investing in sea glider developer Regent Craft as it starts evaluating whether the wing-in-ground-effect vessel might have a place in its fleet. The size of the investment announced on January 26 was not disclosed, but the U.S. start-up said it takes its total funding raised to date to $45 million.

Regent aims to certify its 12-passenger all-electric Viceroy model under maritime regulations with a view to starting commercial services in 2025. In August 2022, certification group Bureau Veritas Marine & Offshore issued an approval in principle covering the means of compliance for the approval.

Last year, the company started testing a quarter-scale technology demonstrator called Squire. These trials were conducted in Tampa, Florida, and at Narragansett Bay in Rhode Island, where Regent is headquartered. The company has said it will have a full-scale Viceroy prototype, with a 60-foot wingspan, ready to start tests in late 2023.

Using current battery technology, the Viceroy is expected to be able to operate on routes of up to around 180 miles. Regent, which says this range could increase significantly as batteries improve, is also developing a larger, 100-seat model called the Monarch.

Regent has conducted ground testing of sub-scale sea gliders.
Regent has conducted ground testing of subscale sea gliders. (Image: Regent)

Seagliders are a type of WIG vehicle that flies exclusively above water by using an aerodynamic phenomenon known as the ground effect, in which air flowing below the vehicle provides lift. The technology represents somewhat of a cross between a traditional seaplane and a hovercraft, although sea gliders cannot hover. Whereas a cushion of pressurized air under downward-facing propellers supports hovercraft, WIGs have forward-facing propellers that direct airflow beneath the craft, creating pressure to provide lift while simultaneously reducing lift-induced drag. 

Each sea glider can operate in three modes: floating on its hull near a dock, foiling on hydrofoils at slow speeds (up to 40 knots), and flying at high speeds (up to 160 knots) just a few meters above the water while cruising. According to Regent, its sea gliders will operate up to six times faster than conventional ferries.

The latest investment comes from Japan Airlines Innovation Fund. The international carrier will evaluate how sea gliders might provide more cost-efficient and environmentally friendly ways to connect destinations across the country’s multiple islands.

“We believe sea gliders are a safe, sustainable, and economical solution and we are excited to work with Regent to assess demand not only in Japan but around the world,” commented the fund’s senior vice president, Yasushi Noda. “We are delighted to add sea gliders to JAL’s list of new challenges.”

Other prospective customers for Regent's sea gliders have included ferry operators, such as Brittany in Europe, as well as regional air carriers like Hawaiian Airlines and Southern Airways Express.