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SeaXplorer 105

What design features are needed to make the ultimate explorer yacht?

24 August 2022 • Written by Sam Fortescue

Ahead of this year's Explorer Yachts Summit top designers share with Sam Fortescue what makes a so-called “go-anywhere” vessel truly suitable for venturing off the well-beaten yachting path

It seems like almost everybody is penning explorer yachts these days. With boats well below the 24-metre mark now badged as “go-anywhere”, you might well be wondering what the term means. In an effort to draw a distinction between the marketing hot air and the icy blast across the deck of a true Antarctic explorer, we spoke to some leading designers.

Damen Yachting's SeaXplorer 60
Damen Yachting

First, we need to get something straight. While every expedition yacht is an explorer, not every explorer is capable of expeditions. EYOS Expeditions co-founder Rob McCallum is something of an expert here, being part of the team that designed and specced the SeaXplorer line of 55- to 105-metre yachts with Damen Yachting.

“Explorer yachts are defined as vessels that have the range and capability to undertake an oceanic crossing unsupported,” he says. “Expedition yachts are those that can operate self-sufficiently in remote areas; places where there is no shore-side support or infrastructure.

Tom van Oossanen

So in one sense, an explorer is simply any reasonably seaworthy boat that can cover the 2,600 nautical miles between Gran Canaria and Barbados on a single tank of diesel. To be suitable for expeditions, however, a yacht must go further – much further. “The primary capability of an expedition yacht is autonomy,” continues McCallum. “It is about provisions storage, garbage management, additional berthing for guides and technical staff and the technical capability to operate within the weather conditions at the destination. Sadly, we see a number of ‘expedition vessels’ which are little more than classic boats with a ruggedised cosmetic veneer.”

The main deck aft ski lodge on the Damen Yachting SeaXplorer 60
Damen Yachting

By EYOS’s definition, autonomy means at least 40 days of operation away from fresh supplies. That’s sufficient for the Northwest Passage (30 days), the remote Ross Sea (30 days), Antarctica and South Georgia (28 days). But it also allows the vessel to stay at high latitudes while guests are flown in for back-to-back charters.

On the SeaXplorer 105, provisions storage amounts to 20 square metres, with another 20 available if required – that’s not far off the average size of a flat in Paris. Managing rubbish is hardly the sexy stuff of superyacht dreams, but it assumes major proportions the longer you stay offshore. On the SeaXplorer, the solution is to powder glass, crush metal and macerate perishable waste.

REV Ocean
REV Ocean

“But it’s far more than logistics that we have input on,” says McCallum. “A fundamental part of what we do is shaping the vessel to best suit  the guest experience, from bow observation areas for wildlife spotting to ensuring the yacht can accommodate all the toys needed for adventures.”

When she’s finally delivered, the world’s largest private yacht, REV Ocean, will also be the largest expedition yacht. Her completion has been delayed until at least 2024 but her dimensions are on another order of magnitude. Her 182.9-metre length can host 106 crew, scientists and guests, keeping them supplied with provisions for at least 114 days. She will have an awe-inspiring 93 cubic metres of fridge space, 76 cubic metres of freezers and more than 400 tonnes of drinking water.

Rossinavi's 38m EXP
Alberto Cocchi

Of course, it is not simply a question of storage. People also need their space aboard, whether crew, staff or guests. Expeditions tend to manage with fewer crew for service, but require more ancillary staff, such as ice pilots, ski guides or wildlife experts. In addition, longer periods away from port mean that accommodation must offer real privacy – for crew and guests.

Rosetti Superyachts has delivered a 38-metre explorer based on the learnings of decades building bulletproof commercial vessels. “From the crew area you can get out of the boat at the bow to get fresh air,” says sales director Andrea Giora. “Normally you’d have to go all the way through the boat to get privacy.” The size of the crew cabins on the 38-metre EXP is also pretty generous. “When you’re out there for weeks and weeks, you want to make sure that the crew is happy.”

Designer Peder Eidsgaard says he tries to encourage owners to see that their guests might like not to see them all the time. “It can be a painful discussion,” he admits. “But it’s not so much about the size of the cabin. To spend time there during the day, you need to have big windows, and we want to provide each guest cabin with a permanent terrace. It allows you to sleep with a sliding door open for fresh air. You are seeking a bit more nature rather than being in an air-conditioned glass box.”

The main-deck lounge on Rossinavi's 38m EXP
Alberto Cocchi

A welcome diversion

With all this talk of technical matters, you might be worrying that there’s no fun to be had aboard an explorer or expedition yacht. But there’s no reason you shouldn’t have some real creature comforts as well. A forward-facing observation lounge is a must for spotting wildlife and marvelling at the scenery. But Eidsgaard’s concept for the 127-metre Rex runs to a 14-metre pool for guests and a private glass-fronted pool forward on the owner’s deck. There’s also a cinema, two-deck gym and a large spa.

“We have sliding glass panels next to the pool so when the boat is in the Med, it’s outdoors with a cover, and when you go the Arctic you can close it off and have it air-conditioned or even heated,” says Eidsgaard. He also favours a spa pool high up with a forward-looking view. “We had that on board Vanish [71.5-metre Feadship] in Alaska and we used it every day.”

The point is to design a boat whose features can be adapted for a tropical climate or for an Arctic one, without losing functionality. Another example is Rex’s dedicated helicopter hangar, which doubles as a squash court when the aircraft has vacated it.

Cloudbreak's wintergarden
Abeking & Rasmussen / Christopher Schole

Designer Espen Øino sees no contradiction between hot and cold climate functions in a yacht. “A pool or a Jacuzzi can be heated up,” he says. “Another thing we’ve done on some boats is to create a winter garden. On [75-metre Abeking & Rasmussen] Cloudbreak, it is on the bridge deck aft – about 50 square metres. The glass panels are suspended in a track in the ceiling and you just pull them out. It takes the crew about a half an hour.”

With REV Ocean, Øino took a radically different approach. The boat will be able to accommodate the Norwegian owner and his family, up to 54 scientists or 28 charter guests in style. But this hugely capable ship is focused on marine science and protection, so key features include an auditorium for lectures and seminars, a large cinema, several submersibles and a moon pool to launch them from inside the boat. There’s also a hyperbaric chamber to decompress after deep dives.

Owners set different requirements according to their passions. For instance, those heading to high latitudes are often keen to take the helicopter for skiing, so a ski room becomes important. “To dedicate a room to skis on board, you have to be a dedicated skier, so why not make it a display room to show off to your friends?” says Eidsgaard. “In one boat, we put it on the foredeck, close to where the helicopter takes off.”

An explorer concept with an 450-square-metre pool deck with open-air lounging and dining on each side of the indoor-outdoor pool

A dive centre might be desirable for exploring in the Pacific, while vehicles are another point to consider. Four-by-four vehicles and off-road bikes are useful on a steep or rocky coastline, while snowmobiles are handy in winter. “When people want to have an explorer yacht, this means that they are going to travel around the world and they want to enjoy different landscapes,” says Alejandro Crespo of Daroca Design. “So, it is important to have a place for good tenders, submarines, etc. I would also include a hangar for a helicopter that gives the possibility to go to the coast at any moment.”

The addition of a helicopter, indispensable for a serious expedition yacht, brings a series of additional extra considerations with it. First on the list is a hangar, so that the aircraft can be adequately protected and secured in rough conditions or inclement weather. Then there’s the question of fuel, which requires careful bunkering and handling aboard – the SeaXplorer 77 carries 15,000 litres of Jet A-1. The pilot will need their own cabin, and you’ll want space for spare parts – along with a mechanic who can fit them.

Tenders also require careful thought, along with their garaging. You’ll probably want different tenders for different occasions, from the limo on the Côte d’Azur to a more robust craft in the Arctic. “For high latitude work it should be covered in a permanent or removable cover to protect from rain and snow, and from the cold,” says Øino. “Plus the possibility to embark/disembark via the bow. There are no docks there, so you just go up to the rock or the snow. Big vertical fenders are also handy for pushing ice away. You need to design flexibility into the concept for extreme climates.”

McCallum takes a simpler view of tender matters, pointing to robustness as the number one requirement. “We are keen fans of the Iguana, which combines excellent seakeeping capability with the very cool feature of simply driving up onto the shore,” he says. “But without doubt, the most useful expedition craft on the market is the Zodiac Milpro MK 5; it is the backbone of the entire expedition industry.”


What not to have on board

The opinion is split here. Some designers take more of a pragmatic approach – such as Philippe Briand, who designed the 55-metre Feadship Shinkai for an audacious owner who wishes to take her through the Northeast Passage. “Pools and glass observation rooms underwater are more suited for Mediterranean yachts,” Briand says. “That is 90 per cent of the market, designed with a lot of open space outside.” Shinkai has just a compact spa pool, leaving space for a seven-tonne submersible on the aft deck, and the heavy-duty crane necessary to launch it. The boat also carries an eye-watering 140,000 litres of diesel tankage – enough to give it a range of 5,500 nautical miles at 12 knots.

Rosetti’s Giora believes that some owners tool up excessively before setting off. “Our 38-metre Emocean doesn’t have the typical flush deck of all the explorers, but we believe we can call her an explorer. I ask myself whether all those toys on the flush deck are necessary. You don’t need three tenders and four jet skis in Alaska.”

Other designers, like Eidsgaard, believe that there are no limits on the facilities appropriate for an expedition yacht. “It is possible to do anything,” he says firmly. “We have a lot of crazy requests, which we try to pare down a little. But anything is possible.”

Going polar

For the purposes of class, there is no difference between an explorer and a Med boat. But dedicated owners sometimes opt for hulls that meet Ice Class. The term covers a huge spectrum of capabilities – starting with vessels that stray into waters with first-year ice less than a metre thick (Polar Class 7) up to those capable of operating all-year round in any ice conditions (Polar Class 1). To date, no vessels have been built to Polar Class 1.

Going Ice Class raises hull costs by 10 to 35 per cent, and imposes certain restrictions on the designer. The hull is thicker to make it harder for ice to pierce, and frame spacing is much closer to increase hull strength. “An ice-classed hull is not necessary unless you’re really going into the ice, where you need protection for the bow,” says Eidsgaard. “We find that’s going too far. For the very rare occasion it’s useful, you pay for that the rest of the year. It is also harder to create that superyacht finish on the thicker hull.”

Triexplorer concept by Marcelo Penna
Marcelo Penna Yacht Design

EYOS Expeditions organises those “rare occasions” when a boat ventures into the ice – Antarctica is among their most requested itineraries. So naturally enough, the Damen SeaXplorer does feature an Ice Class hull. It meets PC7, with a unique double-acting hull, which means the yacht can part the ice going astern too. Besides a bigger safety margin, the advantage is that you can access high latitudes much earlier in the season and have access to the best skiing spots.

Not one for sea ice, but well suited for exploring, the trimaran is the hull form of choice for Spanish naval architect Marcelo Penna. “Compared to monohulls and catamarans, they stand out for their stability, seakeeping and, above all, for their propulsion efficiency. They are the ideal basis for applying hybrid or 100 per cent electric drives.” His Triexplorer concept is based on a successful design for the oil and gas industry, and it offers the storage and cabins of a 70-metre monohull.

Philippe Briand believes that a 50-metre-plus sailing yacht would make an ideal explorer platform, because it has almost unlimited range and is notably seaworthy thanks to its keel. In the end, every explorer design will differ according to the owner’s wishes and ambitions. And according to McCallum at EYOS, the next generation is already in the pipeline. “Double acting hulls, augmented reality, alternative fuels, hybrid energy, interior (layout) flow, enhanced autonomy are all going to combine into the most capable expedition vessels ever designed.”

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First published in the September 2022 issue of BOAT International. Get this magazine sent straight to your door, or subscribe and never miss an issue.

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