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Maritime News

Superyacht Bayesian Sees Daylight Again. 

Last week saw the successful raising of superyacht Bayesian from the seabed. The 56m yacht was launched in 2008 and sank in 50 meters of water off the coast of Sicily in August 2024.  The tragedy claimed  seven lives including its owner, British tech tycoon Mike Lynch, and his 18-year-old daughter Hannah.

Shortly after she sank, the Italian Sea Group (TISG) and CEO of Perini Navi, Giovanni Costantino, made public statements about the sinking in which he blamed a "long list of errors" by the crew and emphasised the "unsinkable" nature of Perini yachts.  He denied any design or construction flaws, claiming the yacht's structure and keel made it a very safe vessel. 

The salvage operation has been led by Smit Salvage and during preliminary operations to recover the superyacht Dutch national and commercial diver 39-year-old Rob Huijben died bringing the number of fatalities to 8.

Bayesian is now in Palermo for forensic examination.

For live updates and on the spot analysis, check out The Yacht Report on YouTube

Conflict In The Middle East

As the tension between Israel, Iran and regional terrorist groups rises, the USA has delivered a significant blow to Iran’s nuclear programme. A programme intended for peaceful work in delivering cleaner power to the region or a front for the manufacture of a nuclear weapon depending on who is describing it. The US strike mission centred on seven B2 bombers each carrying two GBU-57 Massive Ordnance Penetrators (MOPs). The bombs each weigh 13,000kg and are able to penetrate 18m (60ft) of concrete or 61m (200ft) of earth before the 2,400kg warhead detonates.

Speaking after the strike, US President Donald Trump claimed the mission had “obliterated” Iran’s nuclear capability, a claim now in question following military intelligence reports. The follow on repercussions included Iran’s threat to close the Straits of Hormuz, through which 20% (20 millions barrels) of the world’s daily oil supply travels. The threat caused oil futures to rise sharply by 10%.

Boat Chat Focus - Fossil Fuels On Boats

Recent events have made me pause and think about fuel.  In particular about petrol systems but also the wider implications of using fossil fuels in boats.  A potential survey client asked recently if I could survey a 3.5 litre petrol engined ski tow boat that had been converted to run on LPG (liquefied petroleum gas).  Not a common fitment on UK boats and not one I have seen before. Understandably I directed him to his underwriter to give him the go ahead that the boat was going to be insurable before we proceeded with survey.

‘Thankfully’ diesel remains the most popular fuel for small craft in the UK, with petrol a fairly distant second and electric gaining ground but still in third.    Solar and hydrogen both remain quite niche applications (for now) and it is unlikely we will ever see nuclear power in anything other than large vessels. Each fuel brings with it opportunities for performance and cost but also challenges to make the system effective, efficient and safe.  As the old marine adage goes:

Boat Explosion in Turkey

This was brought home in a recent and rather alarming boat explosion on an Axopar 45 XC Cross Cabin. Designed by Finnish company Axopar, built in Poland and fitted with three Mercury Verado 300 V8 petrol outboards. The blast lead to serious but not life-threatening injuries for the three people on board. Thankfully no fatalities reported at the time of writing.

The incident was reported to have occurred following refuelling as the vessel made to depart the fuel pontoon.  The incident was caught on the marina CCTV.

The explosion appears to initiate starboard side forward and the pressure increase lifted the deck moulding away from the hull and moved it to port and aft. Without knowing the vessel layout in detail, most likely line of investigation to start with would be an electrical spark igniting the petrol fuel vapour still present following refuelling.  Given the vessels movement immediately prior to the explosion, the bow thruster would be a good place to start. 

The Axopar 45 range is fitted with triple Mercury Verado 300 4.6 litre V8 petrol outboards.  The design shows the boat to be fitted with a 1300 litre fuel tank located beneath the main cabin floor. A full tank would weigh 1000 kgs.

Refuelling Procedures

Refuelling always demands care and appropriate procedures. That is doubly important when refuelling with gasoline / petrol / 87-octane fuel which these engines use.  The fuel vapour present may have been caused by a spillage, blocked tank vents, loose fill hose, leaking tank or a design defect.  Petrol vapour is significantly more volatile and flammable than diesel vapour and ignites quite easily.

For boat owners, it is essential to always allow time for fuel vapours to disperse. Petrol vapours are heavier than air so will naturally sink into the bilge spaces on any boat. That is why it is critical to use your blowers (if your boat has them fitted) to get the fuel vapours out and fresh air in to the bilges and fuel tank / engine space depending on your boat's layout.

The fuel system layout and specification on many small craft is often less than ideal.  Every small craft design is a compromise in some way and often the fuel system is hidden away, out of sight and out of mind.  Fuel vapour detectors are a very rare sight during my surveys of small craft but this is in part due the majority of boats having diesel fuel systems.  Gas alarms are a lot more common.

The design rules for small craft are usually less exacting than those for small commercial vessels or larger ships. It's a bit of a stretch though to consider anything 45 feet long with 900hp on the transom to be a 'small craft' in the true meaning of the word, especially with a tonne of petrol on board.

Ventilation Is Essential

Ventilation is essential in any vessel with an enclosed cabin, for controlling humidity, managing temperature and allowing flammable and other vapours to disperse.  Ventilation can be either forced or natural and the design will vary according to the design.

For natural ventilation, ideally all vessels would have a mixture of high and low level vents both fore and aft to allow for vertical and longitudinal mixing.  This is a relatively easy thing to set up on a narrowboat or motorboat but trickier on a sailing yacht due to the hull’s heeling when under sail.

Most yachts have small vents built into foredeck hatches or fitted on the saloon roof as well as in the washboards to allow some air to pass through, but this requires a breeze for them to work. Solar powered vents can create small amount of forced ventilation on still sunny days.

Forced ventilation can be either positive (blowing air into the space) or negative (sucking it out).  Engine room blowers on most small craft tend to be negative pressure systems and suck air from low level where fuel and gas vapours will collect to then expel overboard and have static high level vents to allow fresh air back in. This way any flammable vapours get removed quickly from the bilge. It is essential that any electric blowers are ‘ignition protected’ to avoid igniting any vapours.

In larger ships it is more common to have a positive pressure system that produces a modest over-pressure in the engine room to provide adequate volumes of fresh air for engine combustion and helps with cooling of the space.

Fuel Quality

Fuel quality and shelf life standards are both reported to have steadily declined as fuel has been legislated to include more bio-diesel. Many of the additives found in premium forecourt fuel are absent from cheaper supermarket fuel and possibly Marina supplies as well. 

This has had the unintended consequence of shortened fuel shelf life once it is in the tank. Reports of ‘sticky’ diesel are common on the inland waterways and clogged filters and pipes at the start of the season are the typical result.

No easy options to manage declining fuel quality other than buy the best fuel you can get, check where your Marina sources their fuel from and use fuel additives. Diesel Fuel Complete by Marine 16 has been my go to additive for several years.

The old advice was to always fill your tanks before winter storage to avoid water condensation and the dreaded diesel bug. Now it’s preferable to leave them as empty as you can over winter and fill with fresh at the start of the season to minimise the quantity of fuel that goes ‘off’.

Managing Fuel Spills

An interesting observation I picked up on at Crick Boat Show this year was padlock fittings on narrowboat fuel filler caps. They have become an increasingly common sight during surveys and a sign of both the high price of fuel and a reported rise in fuel theft.  The lock is a sensible measure to protect the owner’s fuel, but the fuel diverter fitted around the fuel filling point forces any spilt fuel into the canal, rather than into the vessel.

It is also common to see yachts and motor boats where the fuel filling cap is located to allow any spilt fuel to run overboard into the river / sea.  Perhaps if this design philosophy was reversed so that any spilt fuel went into the boat and forced the Owner to clear up, people would take a little more care refuelling and protect the environment a little better.

All of which brings us back to the Axopar 45 explosion in Bodrum. The intensity and force of the explosion strongly suggests the ignition of fuel vapour within the hull.  It doesn’t take much volume of liquid petrol to produce a large enough volume of petrol vapour to be an explosive quantity.  Detecting the presence of excess vapour and having the means to disperse it quickly and safely are essential in any petrol engined craft. 

The challenge going forward is for boat designs to be safe and easy to operate, even in the hands of inexperienced and ham-fisted Owners and sloppy fuel pontoon operators. Whilst being increasingly mindful of the vessel’s environmental impact when things aren’t perfect and don’t go to plan.

No easy task…

What Else Has Been Going On?

Boat Chat went to Crick Boat Show in May, the UK’s largest inland waterways boat show. Highlight of the show this year was the world’s first all plastic narrowboat.

Made from Polystone-G HDPE (high density polyethylene) supplied by German company Röchling Industrial.  It is a highly durable, chemically resistant material used in many industrial applications including large chemical tanks to keep fluids in. Perfect then for a much prettier container designed to keep water out!

The boat was made in partnership between Adrift Boats and Formation Plastics who have 40 years’ experience of manufacturing plastic structures up to 50,000 litre containers and workboats.  Designed by marine civil engineer Curtis Oyadiran and marketed by Shaun Moir , the hull form was in many ways quite traditional - trad stern, doors front and rear, 6’ 10” beam, well deck forward, propulsion at the rear, tiller steered and a normal layout internally.

For Boat Chat, this was an excellent ‘proof of concept’ and there is clearly a huge amount of potential for this going forward.  No more filling the canal with paint flakes and rust, no more 25 litre tins of petroleum based paint every two years, discarded roller brushes and rags and all the other ways steel hulls pollute the Cut.  Just an annual pressure wash to return the attached marine life back to the canal and check the hull for wear.

In summary, narrowboats built from HDPE are a genuinely ground breaking development for our inland waterways.  Built from a long lasting, low impact and repairable material that can be fully recycled at its end of life.  Coupled with electric propulsion, it offers the enticing prospect of silent navigation of our beautiful canals with a much lower environmental impact.

Read the full Boat Chat report here.

Boat Chat Continues To Grow

Boat Chat continues to grow well and now has over 700 subscribers across all platforms.

Alongside that, the White Hat Marine Surveying YouTube channel continues to upload videos for boat owners, brokers and surveyors all intended to:

‘Helping people understand boats better’.

The most recent YouTube upload looked at how a poorly set up propshaft rope cutter can slow the boat down.

Fitting a rope cutter to your boat’s propshaft is always a good idea and is the easiest way of dealing with the old fishing nets, discarded wire and lobster pot markers that loiter around the coast.  But they need to be set up correctly to do the best job.  On a recent pre-purchase survey of a Beneteau Oceanis 361 Clipper it wasn’t, which made it far less effective whilst also increasing fuel consumption. 

Or as Roy Walker would have said on Catchphrase: “It’s good, but it’s not right”.

Surveyor’s Top Tip for this month - Check the fuel tank fill lines AND vent tubes in your boat. The hoses should be rated for fuel use (BS EN ISO 7840), be well secured with Jubilee stainless steel clamps, be in good condition with no cracks or collapsed sections and have a continuous fall from deck fitting to tank.

Great Kit Ideas

With the boating season in full swing, why not treat yourself to some new gear for the boat owners or marine surveyors in your life or as a treat for your boat. I have put together several collections on Kit.Co which are all personally recommended items and most of which I own.

From boat safety equipment to books about sailing and the tools and books a marine surveyor needs; there really is something for everyone!

Boaty Terminology

Bunker - A (usually fixed) container for storing fuel for the ship’s engine

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