(CNN) A superyacht so extravagant it looks more like something out of a sci-fi movie than real life has taken another step towards its launch as a fully-operational ocean-going vessel.
Sailing Yacht A, Russian billionaire Andrey Melnichenko's latest venture, started its sea testing in Strande, Germany last month ahead of its proposed 2017 delivery.
At 143 meters, it will be the eighth longest superyacht in the world, while its three carbon masts -- each measuring more than 90 meters -- are the tallest of any boat.
All the sails together have the same square footage of a football field and will be able to withstand three times the weight of a commercial Boeing Dreamliner wing. The yacht is designed for a cruising speed of 16 knots (18 mph) and top speed of 21 knots (24 mph).
Read: Is this the ultimate superyacht?
All the sails together have the same square footage of a football field
A conceptual design image of Super Yacht A.
Having amassed his fortune in coal and fertilizers, Melnichenko has a net worth of $11.9 billion, according to Forbes, making him the 139th richest person in the world.
The 44-year-old has spent an estimated $450 million on this vessel, which follows his 119-meter Motor Yacht A.
He reportedly put the latter -- completed in 2008 -- up for sale in April for $300 million. It was photographed last month docked in London's River Thames.
Reinventing the keel
Is it a bird? Is it a plane? No, it's a boat. Or, more specifically, the Tetrahedron -- the new creation from designer Jonathan Schwinge, who's hell-bent on reinventing the superyacht.
Taking its name from the geometric shape, the Tetrahedron Super Yacht is a floating pyramid that appears to have landed from outer space, merging the aviation and maritime worlds.
"I felt it was time that the superyacht world could expand," Schwinge tells CNN. "It's a reinvention of the superyacht idea -- a superyacht that does not look like a superyacht in any form but which has had, however, a quantum leap aspect to it."
With its main body perched on a submerged torpedo-shaped hull via a vertical strut, the Tetrahedron offers an elevated mode of travel above the ocean's waterline -- giving the impression of a boat that can fly.
It is made possible by the HYSWAS (hydrofoil small waterplane area ship) hull, which enables the vessel to be lifted out of the water at speed on side-mounted adjustable hydrofoils. When traveling at a lower speed, meanwhile, the Tetrahedron sits gently onto three underbelly hulls.
"The result is a futuristic, exciting and totally unconventional flying superyacht which seems to have captured the imagination," Schwinge says.
"It's completely unrecognizable as a superyacht, with a mystical-looking pyramid form contributing to a very futuristic profile on the sea," Schwinge says. "From a distance it's not clear which direction it's traveling in, creating further illusion and mystery."
Made from carbon fiber and duplex stainless steel, the Tetrahedron is 25 meters long and can reach speeds of up to 38 knots (43.7 mph) over a range of 3,000 nautical miles. According to Schwinge, it has drawn influence from the America's Cup racing world and the Maritime Applied Physics Corporation's (MAPC) Quest boat (pictured).
The Tetrahedron's HYSWAS hull is based upon an existing design which was used by MAPC's Quest in 1995 as a technology demonstrator.
Scwinge says the Tetrahedron will provide a surprisingly smooth ride at sea. "Once the yacht has reached take-off speed and has lifted above the waterline, a wave can pass underneath the hulls with virtually no pitch or heave," he explains. "The 'in-flight' mode would mean that your coffee would remain remarkably level and without spillages -- a smooth wave-flying experience at speed."
Unspillled coffee is not the only luxury guests on board will be able to enjoy. When docked, the Tetrahedron's three sides can fold down to become enlarged sun decks boasting an outdoor dining area and easy access to the water, while horizontal panels emerge overhead to provide shade.
"It's a private island with openable 'beaches' to the sea," Schwinge says, adding that the vessel will preserve the traditional luxury of yachts but possess a "super-lightweight special interior" similar to private jets.
Its cost and planned release date are strictly confidential but there is a "continuing interest" in the concept, according to Schwinge.
"The Tetrahedron is suitable for private, charter or corporate use," he says. "But a private owner would be a visionary and innovative individual who wants to experience new technological ways in elevated yachting, with 'wave-flying' capabilities and a radically unconventional design."
Designers unveil concept for private floating island
The world of yacht design has seen some pretty out-there concepts in recent years -- from
boats inspired by Lego, to space-age
ships resembling a Concorde jet on water.
But it's fairly safe to say that nothing comes close to
Kokomo Ailand -- the 80-meter-tall private floating island featuring a waterfall, shark feeding station, and two beach clubs.
Perhaps most unbelievable of all, is that Kokomo is not beyond the realms of reality. In fact its designers,
Migaloo, will be showcasing their plans at the
Monaco Yacht Show this week, and have apparently already received "very strong" expressions of interest from clients across the world.
We take a closer look at the jaw-dropping design.
The fantastical vessel is yet to be given a price tag. But as the designs go on show besides multimillion dollar superyachts at this year's Monaco Yacht Show, you can bet it's going to be outside the budget of mere mortals.
So what kind of person would actually buy a vessel like this?
"An open-minded, visionary owner, who wants to stick out of the mass with his unique design," said Migaloo's Managing Director, Christian Gumpold.
"They would be a real trendsetter and somebody who loves traveling long distances."
When it comes to superyachts -- and their multimillionaire owners -- is there ever such a thing as "over-the-top?" Gumpold thinks not.
"Clients always demand the extraordinary design, and we as designers try to fulfill their dreams," he said.
"Large waterfalls, living plants -- these are an upcoming trend on megayachts. We just took these features to another level."
To the untrained eye the vessel might bear a passing resemblance to an upmarket oil rig -- albeit one that is a lot more luxurious.
The futuristic floating island features a penthouse perched 80 meters above sea level, two elevators, and a jacuzzi with a glass bottom.
Should you wish to move the hefty vessel, expect to take your time, with speeds of eight knots.
"It is more or less a piece of floating land," explained Gumpold. "It can be supported by custom-designed support vessels, as is a trend in the yachting industry right now.
"So it is like a offshore main basis or hide away, and from there you are free to go anywhere."
"Living on and with the sea will be a future mega trend -- and the island can be a first step to adapt to this new way of living," explained Gumpold.
"We've noticed a strong trend towards individualization in the current superyacht market, so we wanted to create something completely new."
"The design of the island is inspired by nature," said Gumpold of the vessel which includes a helipad and underwater dining saloon.
"It's features reflect the beauty of a secret hideaway -- but we interpreted everything in a modern architectural way, without simply trying to copy it."
And what floating island is complete without an extravagant underwater toy to accompany it?
The company's submersible yacht concept (pictured) comes in a range of sizes, from 72 meters, up to 283 meters. Gumpold explains that the floating yacht would act as a "mothership," from which this sleek underwater vessels zips you across the ocean.
But in what ways is a submersible yacht such as this, different from a submarine?
"It's way more stable on the surface than a conventional submarine and offers extraordinary large interior spaces," said Gumpold.
"And all features of a superyacht, like helipads, beach clubs, side balconies, terraces and pools can be added without loosing the ability to dive."
Because sometimes, having just one helipad on your floating island, just isn't enough.
The alphabetically-aware Melnichenko named both boats "A" so they appear at the front of shipping registers.
Motor Yacht A, which received mixed reviews upon launch for its head-turning design, costs $500,000 to refuel. The eight-deck Sailing Yacht A, which is motor-assisted, is likely to be as expensive, needing a refill every 5,320 nautical miles.
"Andrey Melnichenko is a man with exceptional vision," Boat International magazine wrote in 2015 after Super Yacht A's design details were released.
"Where other yacht owners like to blend into the background, he wants his superyachts to push the boundaries of design, creativity and technology as well as make a statement.
"His first superyacht, Motor Yacht A, rocked the superyacht world with its radical design and now he's done it again. "
Like its predecessor, Sailing Yacht A was designed by Frenchman Philippe Starck. It was built in Nobiskrug shipyard, Germany, while UK-based Magma Structures constructed the masts.
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Progress of the build has been kept under wraps, but Melnichenko doesn't have long to wait before he can finally set sail.
Makes clear that all the sails together have the same square footage of a football field.