Aircraft

Watch the world's first hydrofoiling ground effect vehicle take off

Watch the world's first hydrofoiling ground effect vehicle take off
Regent's quarter-scale Seaglider prototype lifts its hydrofoils out of the water and flies
Regent's quarter-scale Seaglider prototype lifts its hydrofoils out of the water and flies
View 9 Images
Regent's quarter-scale Seaglider prototype lifts its hydrofoils out of the water and flies
1/9
Regent's quarter-scale Seaglider prototype lifts its hydrofoils out of the water and flies
The next prototype will be a two-pilot, 12-passenger model that's expected to become the company's first product
2/9
The next prototype will be a two-pilot, 12-passenger model that's expected to become the company's first product
The Seaglider uses automated flight controls to keep it within about a wingspan of the surface, to take advantage of the wing-in-ground effect
3/9
The Seaglider uses automated flight controls to keep it within about a wingspan of the surface, to take advantage of the wing-in-ground effect
Members of the Regent team with the 18-foot prototype
4/9
Members of the Regent team with the 18-foot prototype
From a drawing on the back of a napkin to a flying quarter-scale aircraft and US$7 billion worth of order
5/9
From a drawing on the back of a napkin to a flying quarter-scale aircraft and US$7-billion worth of sales in just 15 months
Regent's design can taxi in the water, accelerate on its hydrofoils, and then lift off to enjoy the enormous efficiency of ground effect flight
6/9
Regent's design can taxi in the water, accelerate on its hydrofoils, and then lift off to enjoy the enormous efficiency of ground effect flight
A full-scale demonstrator is next, with a 65-foot wingspan
7/9
A full-scale demonstrator is next, with a 65-foot wingspan
The quarter-scale unmanned prototype on the water
8/9
The quarter-scale unmanned prototype on the water
Regent is operating at breakneck pace, with the first commercial services slated to
9/9
Regent is operating at breakneck pace, with the first commercial services slated to start taking passengers in 2025
View gallery - 9 images

Regent has released video of its remarkable Seaglider prototype in flight testing. The first machine to combine the efficiency advantages of ground effect and hydrofoiling in a single design, it promises revolutionary speed and range in coastal areas.

Wing-in-ground effect (WIG) aircraft such as the Soviet-era Ekranoplan have shown promise in the past, but they're yet to take off, so to speak, as a mainstream form of transport. These low-flying birds ride on a cushion of air between their wings and the surface, which gives them a significant lift and efficiency boost over regular planes flying higher in the air – as long as they stay within their own wingspan of the surface beneath. This extreme altitude restriction means that while ground-effect aircraft could fly over land, it's too dangerous for regular operations, and they typically stay over water.

The numbers haven't been attractive enough to date, but the era of electrification brings a set of new incentives to the game. Electric boats are struggling to prove their worth; batteries simply don't hold enough energy to push through the tough medium of water for long distances. Early electric aircraft struggle to deliver useful range with a decent number of passengers on board, too. Regent looked at this, and saw a situation where the efficiency of the old ground-effect vehicle could give it a genuine commercial advantage, if paired with another, more recent technology.

From a drawing on the back of a napkin to a flying quarter-scale aircraft and US$7 billion worth of order
From a drawing on the back of a napkin to a flying quarter-scale aircraft and US$7-billion worth of sales in just 15 months

That would be the hydrofoils. Regent's Seaglider is designed to taxi slowly like a boat, with its V-shaped hull/fuselage in the water. As it speeds up for takeoff, it rises out of the water on a set of hydrofoils. This takes the cabin up out of the waves, making it glide smoothly above the surface for a comfortable ride. It also vastly reduces drag, and thus also the energy required to push through the water, so it uses much less energy reaching takeoff speed for wing-borne flight. The hydrofoils fold out of the way once the aircraft is out of the water, and descend again for landing.

The result, claims Regent, is pretty remarkable: a quick, quiet, comfortable, 14-seat electric coastal transport capable of covering distances up to 180 miles (~300 km) at speeds up to 180 mph (300 km/h) with zero emissions – using today's commercially-available batteries. It should be cheap – half the operating cost of an aircraft, and lightning-fast, at some six times the speed of a comparable boat. And the concept is scalable, too; the old Ekranoplans became more efficient with size, and these should, too. Regent has its eye on versions up to at least 150 passengers.

The market sure seems to be responding; Regent says it's taken pre-orders for an extraordinary US$7-billion worth of sales, including a decent swag of deposits on aircraft of various sizes.

The quarter-scale unmanned prototype on the water
The quarter-scale unmanned prototype on the water

Now, the company has shown the first video of its prototype, a quarter-scale Seaglider with a wingspan around 18 ft (5.5 m). Embedded below, the video shows the machine in slow taxi, fast, smooth hydrofoiling, takeoff, wing-borne cruise and landing.

It's all shot in fine weather and relatively smooth seas, but it's certainly impressive to see how gracefully these things hydrofoil. Takeoff and landing look a touch more exciting, and indeed we're interested to learn what the experience is like in the cabin as they hit the water and slow down – but it'll likely be a friendlier landing than that of a seaplane, and there are plenty of those in service.

Regent has already raised the $18-odd million it needs to take the next step: building a full-scale prototype with a 65-ft (19.8-m) wingspan for manned trials, which it hopes to commence in 2024. It hopes to be in mass-production, and for the Seaglider to be taking paying passengers, by 2025.

The next prototype will be a two-pilot, 12-passenger model that's expected to become the company's first product
The next prototype will be a two-pilot, 12-passenger model that's expected to become the company's first product

That's an ambitious timeline, but Regent has brought serious money on board, and has already demonstrated its ability to move at breakneck pace. And it has a considerable leg up over next-gen aircraft, such as electric VTOL air taxis, by virtue of the fact that it can certify this thing as a WIG maritime vessel, avoiding the bottleneck of FAA type certification.

“People have been attempting to make wing-in-ground effect vehicles viable for 60 years, and in 15 months we have gone from a drawing on a napkin to the first successful flight.” said Mike Klinker, Regent CTO and co-founder, in a press release. “Regent is the first team in history to overcome the deficiency of low wave tolerance with past designs by combining high-speed hydrofoils with ground-effect flight – a crucial innovation that will revolutionize coastal transit. No vehicle in history can match the combined wave tolerance and speed of our seaglider.”

Check out the video below.

REGENT Seaglider Achieves First Flight

Source: Regent

View gallery - 9 images
19 comments
19 comments
jeronimo
I hope Regent will stay the distance with this commercial venture. Some of the current "customers" like Ocean Flyer from NZ, are making very bold claims about the routes they will fly around NZ. The reality will be that some of these routes will not be suitable in anything but dead calm weather. Simply because the coast around NZ gets very rough, very quickly and has sizeable, long period swells making surface skimming flights hazardous.

For sheltered waterways, this could be a great way to travel, as long as other water users know where the "flying" lanes are.

Also, unless Joe and Jane Public have a thrill-seeking temperament, they might find surface skimming 20m above the sea at 300 kph pretty daunting.

Top marks to Regent so far.
jeronimo
Interesting how the 1/4 scale flying model uses a slat on the leading edge of the horizontal stabiliser. They must have had some flow stability issues with sudden changes in the angle of attack of the stabiliser.
Jim B
@jeronimo - Ocean Flyers website says that 540km/hr and 800km range are available. If they swtiched from batteries to liquid hydrogen and a fuel cell they might be able to do Auckland to Sydney flights in around 4 hours. That would probably be faster than turbofan jet airliners by the time you count check in and travel to and from airports.

Also, if they can glide 20m above the water... there aren't too many 20m waves about so they might be able to do ope ocean flights.
EH
The horizontal foil is efficient, but when landing there will be a sudden jerk as the whole foil touches the water, which could be very dangerous. A V-shaped foil would smooth the transition. Ekranoplans are neat, but they really need advanced electronic controls since bad things frequently happen faster than a pilot can react when you're going that fast at that altitude over uneven, constantly-changing waves.
Christian Lassen
Looks pretty wobbly in the air. Like a recipe for sea-air sickness
BlueOak
Very cool stuff and seeing it actually operating as claimed - no rendering going on.

As to the “shock” of the foils hitting the water when landing - speed is everything - the question is what is the stall speed of the wing? If it is slow enough then it seems designing the proper water foil should be doable.
howellpm
the flight transition looked awkward as the plane popped up far too high for ground effect which suggests excess of power for the concept , why?

the trasition to water landing configuration did not appear to use the lauded hydrofoil interface , simply dropped onto the hull.

what we see is an hydrofoiled seaplane - which may have been done a while ago . Nevertheless good luck if it can be cheap and quiet .. see this space in 2025
jerryd
I think 20s- 50s seaplane pilots would beg to differ as they commonly flew in ground effect to increase range on transcontinental flights.
Russians, etc have been using them since the 60s.
In fact the first commercial passenger flight happens in Tampa Bay flew from St Pete to Tampa in ground effect since with a passenger it didn't have enough power to get out of ground effect. and flew right by the company's new Test place in Port Tampa.
Hydrofoils are not needed and a much better idea would put a waterjet drive in the main hull to help take off and so the props can shut down getting close to the dock.
Ch.Lucas
Hi,
very close , but not a real ground effect plane was the Lisa , http://lisa-airplanes.com/en/private-plane-manufacturer/innovation/seafoils/ .
But i think every plane is in itˋs way using ground effect . The straight foils are not very smoth when touching the water , a V shape will be better or a ski like Sea Dart used .
Nelson Hyde Chick
Do the hydrofoils change add any lift once out of water? They must.
Load More