MSinking of the 56-meter-long yacht last week Bayesian and the tragic deaths of British technology magnate Mike Lynch and his guests and boat crew have given the public an insight into the exclusive world of superyachts.

From the sheer size of the mast (74 meters, about the size of seven two-story houses stacked on top of each other) to the cost (Bayesian was put up for sale in 2014 with an asking price of $30 million (around £23 million) to sheer luxury (the interiors are by Remi Tessier, the designer behind Claridge’s new penthouse), it’s a world that few people usually get to see.

There are currently 12,626 superyachts in operation around the world, with 1,166 under construction or on order. If you’ve been to a Greek island this year, or perhaps the Amalfi Coast, you may have seen them entering and leaving ports and wondered who owns one. Or who can afford to charter one – the average price of which is around £180,000 per week.

While you may be thinking of glossy influencers and A-list celebrities, the superyacht community is where millionaires are separated from billionaires from centi-billionaires; the 0.001 percent. You’ll rarely find a celebrity financially strong enough to afford a yacht that Lynch owns. These tend to be industry giants that fly under the radar and aren’t household names.

So what exactly makes a superyacht a superyacht? According to Boat International, where I work, this can be applied to any boat, motor or sailing yacht, that is longer than 24 metres. Size is everything in the world of superyachts – and yachts are getting bigger. In fact, our data arm BoatPro shows that the average length of a new-build yacht is now 39.2 metres, up from 38.5 metres last year.

The largest yacht in the world is currently the motor yacht Azzam – at 180.6 meters, almost two football fields long and three times the size of Lynch’s BayesianOwners can purchase yachts as a “semi-custom” yacht (similar to a new home built from plans but on a much larger scale) or as a “fully custom” yacht, meaning they are built from scratch to the owner’s exact specifications.

And it’s not a quick process either: it can take up to four years from design to completion, with 300 or more people working on each project. All of this perhaps explains the insanely high costs.

While this price fluctuates depending on market fluctuations and demand, a fully customised 100-metre yacht with all the trimmings will cost around £200 million. And that’s just the start. Depending on the size and age of the yacht, you’ll need to spend at least 5-10 per cent of the purchase price each year on maintenance and running costs (in this case, £20 million for crew, fuel, taxes, insurance, port fees).

Some owners want to recoup some of their running costs by turning their yacht into a mini hotel business and chartering it out. A commercially successful boat (neutral interior, jacuzzi, lots of luxury toys) is chartered out several times a year, covering the traditional charter areas of the Mediterranean in summer and the Caribbean in winter.

The 85-meter-long yacht ClearlyFor example, it is equipped with an open-air cinema, a helipad, a teppanyaki grill, inflatable boats and water skis – a bargain at £665,000 a week.

While many prefer to keep a low profile, other yacht owners like fashion designer Tommy Hilfiger are not so shy and like to use their yacht for entertaining (in Hilfiger’s case, Kris Jenner of the famous Kardashians). But most of the time, the owners are very private. (Lynch was one of those owners who liked to keep it low profile.) Often, even the construction of the yacht can be shrouded in secrecy, and the engineers and craftsmen working on it don’t know who the owner is.

Unlike a car, yachts do not lose value quite as much. However, you have to keep them in perfect condition. That’s work: This also applies to the Netflix hit Below deck – The team actually cleans the cracks between the floor tiles with toothpicks.

If you do maintenance regularly, your yacht will last 70 years or more. Christina OThe legendary superyacht that once belonged to shipping giant Aristotle Onassis and his wife Jackie O is still in top shape at 81 years old. It was recently put up for sale for €90 million (£68 million).

For your 100-metre yacht, you need a crew of at least 20. Not TV crews, but those with professional qualifications that you would trust to handle your multi-million pound equipment.

Good captains are in high demand and can name their price. Sailing guests to exotic parts of the world is only a small part of the job: you have to plan safe routes, book berths in marinas (expect to pay over €117,000 – about £99,000 – for the week of the Monaco Grand Prix), manage the crew, do loads of paperwork and organise repairs and shipyard visits.

Simply taking the boat to the local workshop for maintenance is not enough. This also explains why guests must remove their shoes before boarding to protect the valuable teak deck.

And unlike other status symbols such as supercars or valuable watch collections, you can’t just dock a superyacht and forget about it until your next luxury vacation. They need constant attention – as the US government discovered to its detriment when it Amedeaa 106-metre superyacht owned by a Russian oligarch, and found that they were spending $7 million (£5 million) a year on maintenance.

That’s why superyachts become such passion projects, regardless of whether they’re worth it or not. Owners don’t just own them, they put their heart and soul into them. And that’s where the fun begins.

Despite the industry’s tasteless reputation with its gold faucets and bling-bling, many owners are extremely creative with their superyachts: underwater “Nemo” lounges, indoor gardens, waterfalls, snow rooms, paddle tennis courts, IMAX cinemas… there are no limits to the imagination.

Innovation is at the heart of the industry and is tailored to meet individual needs. Some owners prefer the power and thrust of sail over the engine and a more intense sea experience.

Some people want a ship that can sail around the world so they can really see the world. BayesianFor example, was built for use in locations and her sister ship Rose Heart (an almost identical yacht built by the same shipyard) has been taken around the world several times in all weather conditions without any problems.

Some owners have their yachts built with a sturdy “ice-class” hull so they can visit the poles. These yachts are called “explorer yachts” and feature laboratories for visiting scientists, personal submersibles, James Bond-style “moon pools,” openings in the hull to allow submarines to dock, and so on.

Sometimes an explorer yacht isn’t big enough to handle everything an adventurous owner wants to do, which is where supply vessels come in (secondary yachts used to store equipment like seaplanes and snowmobiles).

Why have one yacht when you can have two?

Some forward-thinking owners are investing their money in researching more environmentally friendly alternatives to traditional diesel engines. The world’s first hydrogen-powered superyacht, Project 821which is 119 meters long, is said to have been launched this June. Project ZeroA “fossil fuel-free” sailing yacht that can use wind, heat and solar energy will be launched in 2025.

There was much speculation about the cause of the tragedy with BayesianSuperyachts have been known to suffer accidents, but instead of sinking in storms, they run aground or catch fire (in some cases, lithium batteries have been cited as the cause). Due to the long timescale and complex technical reports from investigators, we often never find out the cause.

Now it’s up to investigators to find out how an “unsinkable” yacht sank last week. The facts are: Bayesian was built by Perini Navi, a prestigious shipyard specializing in sailing yachts based in Italy, the world epicenter of shipbuilding. Every day, 30,000 engineers, architects and designers work here, proud of their unparalleled craftsmanship, pushing boundaries and achieving incredible engineering feats using sophisticated shipbuilding technology.

The world of superyachts may be a world you and I will never be a part of, but as this week’s tragic news has shown, there is much more to it than you think…

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