The last navigator

Do you really prefer hitech modern satellite navigational gadgets to the romance of the stars and traditional methods, asks a friend? Actually, I think the question raises another: is there really a low tech traditional method in our modern sense of it? For most people, tradition means compass, sextant and chart.

A Micronesian sailing canoe, from The Last Navigator

As I mentioned in an earlier post, I have been catching up with a second hand copy of The Last Navigator by Stephen D Thomas, printed in 1987, which explains exactly how Polynesian navigators have been achieving remarkable feats of accuracy for thousands of years before even the compass was invented, let alone the sextant. The book has underlined for me how hi-tech our “traditional” methods of navigation really are.

A diagram of a sailing canoe from The Last Navigator

For the last 250 years navigators have in reality relied on precision instruments and almanacs full of mathematical calculations of great sophistication. These are methods, materials and advanced technologies that would have astonished the ancients.

A maritime chronomoter, key to longitude measurement, was a major technological achievement of the 18th century, while in its day the modern sextant was a leap forward in precision engineering. It simply was not possible before the 18th century to make instruments of such accuracy.

A great deal of learning and practice went into using both chronometer and sextant, in combination with the immense data resources published in nautical almanacs and the even bigger resource of worldwide nautical charts created by meticulous surveying.

Actually, you don’t even need to learn where all the stars and constellations are to use a sextant. The tables tell you where to look, using your compass and sextant and a rough approximation of how far you have gone since your previous position fix. That surprised me when I learnt how to use mine (a late starter because it was only 20 years ago). There is satisfaction in being able to find and recognise the constellations and the main stars from memory, but it is not at all essential.

Contrast all that with the methods of Polynesian navigators. They are well known to have had no instruments and charts, and to have relied entirely on reading the stars and waves and watching for birds and sea creatures. An aura of mysticism and magic surrounds those achievements. But The Last Navigator brings out the detail of how they actually did it, and it reads as an astonishing feat of memory and long practice, which in its underlying method turns out to connect directly with what we do nowadays.

They used the rising and setting positions of many different stars as their compass; they read information about currents and directions in subtle changes in wave patterns and the surface ripples of water; and bird and sea creature behaviour gave them information about distances from land.

In their heads, they carried the equivalent of a chart of Pacific islands. They fixed their position on it by seeing, in their minds, where lines from the rising and setting points of stars on the horizon intersected, using a reference island chosen for the particular passage they were on.

It was the use of position lines that I found most intriguing. Far from being some unknowable ancient and mystic puzzle, Polynesian navigation essentially did what we do now. Underneath everything was a geometry common to all methods of position fixing. Finding the intersection point of lines from stars and other known objects is the basis of every type of navigational position finding.

Intersecting lines are used by the computer in your GNSS receiver to calculate a position using signals from satellites. “Traditional” navigation using a sextant and chart uses lines measured from precise instrument readings of angles in the sky. For thousands of years Polynesian navigators have achieved a similar feat using no aids at all but memory, observation and experience.

If you want truly to learn to navigate with the romance of the stars and a deep understanding and feel for the natural world, you will have a long way to go. According to Wikipedia, by 2014 these skills were still taught only in the outlying Polynesian island of Taumako in the Solomons.

A new edition of The Last Navigator is still available in paperback, though search now under Steve Thomas, not Stephen D. The charm of the book is that it combines the story of a young man’s ocean adventuring with his quest to be taught the old arts before they disappear.

I also found on Amazon what looks like a much more detailed manual of techniques: We the Navigators: Ancient Art of Landfinding in the Pacific by David Lewis. If I could find a copy for less than £30 I would buy it! There are several blogs for enthusiasts of Polynesian and Micronesian navigation and quite a few replicas have been built to sail.

March – Spring and fever

Our plans are changing rapidly, just like everybody else’s in all walks of life in Europe. Sailing now has to be a peripheral concern, but we still have to work out what to do with the boat, and indeed whether we can sail it at all this year.

No sooner had we decided to go to southern Brittany rather than our original destination of Spain than the fight against the Covid 19 virus made that new plan difficult and probably impossible. It is only a couple of weeks since we applied for a 12 month mooring for Spring Fever at Arzal on the lovely River Vilaine: not surprising we haven’t heard back, because southern Brittany has a local concentration of infection, and the marina is now preoccupied with far more urgent matters. It has announced a strict plan to protect its staff and customers.

In any case, the outlook now is for a continuation of virus defensive measures right through the summer and into autumn. Even if there is a relaxation after the first three months of restrictions, current official projections suggest that there is a high likelihood that it will be temporary, with a further set of measures later. There is a strong probability that the emergency will last a year.

So even if we were welcome in France – which we certainly would not be during this next three month phase of the virus – we could never be sure of getting back to the boat from England after we left it there.

Pin Mill, on the River Orwell near Ipswich, the Butt and Oyster pub on the left

One fall back plan is to have a nostalgic sail up the channel and round to Essex and Suffolk, and keep the boat there for a while, if conditions ease.

A sail up channel is enjoyable (you scoot along, riding the flood tide, for a full 11 hours from Beachy Head if you time it right) so fingers crossed that we can at least go sailing at some point. It will be quite a while before we’ll know whether that is achievable.

In the meantime, there is no point in rushing this spring’s work programme, and some of it could wait till next winter.

Footnotes

(1) An email 24 March from Cowes Harbour Commission saying our boatyard, Cowes Marine Services, is closed indefinitely to customers and contractors. So are Shepherds marina and Cowes Yacht Haven, which made the announcement earlier. Terrible news for the people earning a living from working on our boats, but expected.

(2) One reason for wintering on the continent was to keep our EU status at the end of the transition period on 31 December. Will Boris Johnson’s government stick to its pledge not to ask for an extension, given everything else that is happening? If they give in and ask, we’ll have more time to get to France – next year.

Relearning old navigation lessons

Two letters in the latest issue of the excellent Cruising Association magazine* claim it is now safe to rely entirely on electronic charts because backups to the boat’s main chartplotter are so cheaply available. You can leave your old paper charts abandoned in the bottom of a locker somewhere, the argument goes.

However, while researching updates for the yachtmaster book I mentioned last month, I’ve been re-reading intensively about old fashioned navigation techniques I learnt a long time ago, some of which were beginning to fade from memory. It has reinforced for me how important it is to avoid total reliance on electronics and have a portfolio of navigation skills including the old ones.

Traditional chart table at the end of a sail home from Scotland, and the bottle we brought back to celebrate our return .

So I think discussion of electronic charts needs to be a lot more nuanced than some of their more enthusiastic users suggest. Yes, on Spring Fever we have also relied heavily on electronics for many years, but my worry is how easy it is for phone, tablet and laptop software as well as hardware to fail, which can take a long time for the less than totally expert to sort out on passage.

It is certainly true that most well equipped offshore boats will have one or more extra chartplotters loaded on tablets, phones and laptops. Some are backups in case the main plotter system run from the boats batteries fails – that only takes a bust alternator or an engine that refuses to start. I also hear that an increasing number of people are dispensing with dedicated marine chartplotters altogether and relying on tablets etc.

Two examples of what can go wrong: my tablet’s GPS receiver failed last year. After a great deal of googling back home I found out why – I had not updated it for the GPS clock change that took place last year (little noticed, but the navigation equivalent of the millennium bug in 2000). Updated this winter using wifi at home, the GPS started working again, ready for this season. Hands up all those who knew about this and fixed it in advance. My problem was an older tablet. Recent ones would have updated for it automatically.

This was specifically a US GPS problem, and I don’t think it affected the wider GNSS, which includes the Russian, European and Chinese satellites processed by newer receivers than the one in my tablet.

More seriously, my laptop had earlier ground almost to a halt because of some unknown and untraceable software issue picked up I know not where – probably not a virus, or at least not one my Norton protection could find. I abandoned it for navigational backup and planning in favour of the tablet, well before that too showed it could let us down.

This winter, having bought a new laptop, I did a factory reset on the old one, wiping everything except the Windows 7 operating system. Miraculously, it now works like new. So I have loaded the charts, GPS driver and related software again and it is going back on the boat and staying there. I will keep it bug free by not connecting to the internet.

The laptop will be used for planning, with the cockpit chartplotter still our main instrument. But the laptop is old and has a hard disk drive rather than a solid state one, so can mechanically wear out. We may add a further backup in the shape of a small, cheap 7 inch tablet from visitmyharbour.com that’s tough and cockpit proof. (£170 loaded with 2020 raster charts for the UK, France and Atlantic Spain and Portugal).

Computer hotshots might have done fault-finding at sea or in a marina but it took me a whole day at my desk to figure out the laptop solution and sort it, using a high speed internet connection. The software fault had even disabled the DVD drive, which is now working again.

This is not the end of the list of issues. Tablet and phone navigation relies on apps and they do sometimes misbehave. Often the solution is to uninstall and download again – not an option for us at sea. That problem cropped up last year not with a chartplotter app but with one of the best tide prediction apps, though it could easily have been one of the chart apps. This all tells me – a reasonably capable but far from expert user – that the issue of electronics reliability, even with multiple backups, is complicated.

And that is without more basic questions, the first of which, GNSS reliability, I have covered in two previous posts. (On that subject, I have just read a report that GPS spoofing equipment can now be bought for only $100, and how to use it is widely discussed on line).

There is of course the more widely considered question of what happens to your backup tablets, phones and laptops in a knock down, a partial flooding of the saloon, a fire that you may put out but which causes damage or – a nightmare – a lightning strike.

I’ve had a strike on a previous boat, while it was moored on a river – I was ashore – and it destroyed all the electronics and made for a large insurance claim. High voltages nearby can induce large currents in equipment even if it is not wired into the boat’s own circuits. The advice I hear to stick your laptop, tablet and phone in the oven to shield them if lightning is near I find the complete opposite of reassuring!

So we don’t plan to chuck the paper charts, dividers, almanac and ruler in the bottom of a locker somewhere – they’ll always stay ready in the chart table, and we’ll use them from time to time so as not to forget how.

By way of contrast: now reading this 1987 book, which makes even our traditional navigation seem hi-tech. It’s about the last island outposts of Pacific Ocean navigation skills going back thousands of years, which use only knowledge of stars, waves and birds, and no instruments, achieving remarkable accuracy.

* Cruising, Spring issue.

Bowsprit – pronounced bow, bo’ or bogh?

How do you pronounce bowsprit? I’m usually against language pedants, who try to foist the views of Victorian grammarians onto the 21st century. But this word is my one little obsession, ever since getting a letter into Yachting Monthly on whether the first syllable of bowsprit should rhyme with dough or cow.

I was reminded by contemplation of this lovely boat recently.

I can’t remember why or when, but I learnt to pronounce bowsprit to rhyme with dough as a child. In fact, the similar word bowline is always pronounced like dough. So why the difference?Nobody contradicted me on bowsprit till adulthood, partly, I suppose, because I did not know anyone with a boat with one.

But once I met people who used the word practically rather than just read about it, I found myself in a tiny minority: indeed, a handful of people I met were so irritated by my pronunciation that I wrote to Yachting Monthly for a ruling.They published the letter and the deputy editor sent me a private note saying he agreed with me that it should rhyme with dough – but it was obviously too sensitive an issue for such an important journal to take sides in public!

The Oxford English Dictionary agrees it should rhyme with dough, deriving the bow in bowsprit from Middle Low German and Middle Dutch. The online OED can speak the word, too, and it is my way.

I know I am being a touch inconsistent, because I am also convinced that language should evolve the way people actually use it, and not be held back by pedants (see books by David Crystal and David Shariatmadari).

So mine may be a losing battle. The reality is that the pronunciation of bowsprit has changed with popular usage – but don’t expect me to give in any time soon….

February – averting satellite disaster

The British government turns out to have been ahead of the game on the  satellite risks I mentioned last month, with a £36 million programme just announced to  prevent navigational satellite failures damaging the economy by as much as £1 billion a day. It is feared that the entire country has become over-dependent on a handful of satellite systems.

Emergency services, the energy grid, mobile phones, Satnav, broadcasting and other communications, the Stock Exchange and an array of other activities all rely heavily on the super-accurate timing provided now by navigational satellites such as GPS and similar systems. There are life-threatening risks from failure, says the government.An image of a third generation Lockheed Martin GPS satellite

The new investment is in a National Timing Centre to create a network of super-accurate atomic clocks around the UK, accessed through ground-based communications, so that the economy will no longer be over-reliant on timing from GNSS signals from the sky.

GNSS is the term that embraces the US  GPS, the first system, Russia’s GLONASS satellites, Europe’s new Galileo and also a rapidly developing Chinese system.

Galileo failed completely for a while last year during its start up phase, because of operator errors, and there are now many examples of interference with GNSS systems and malicious ‘spoofing’, in which navigation instruments are fooled into thinking they are somewhere else. The heart of all navigation by satellite is accurate timing, without which positions cannot be fixed.

The Business Department said the centre will provide additional resilience against the country’s reliance on accurate timing, which underpins many every day technologies.  “ If there were a large-scale failure, economic impact to the UK would be £1 billion a day”, the department said. “Loss of this accurate data would have severe and life-threatening effects, such as on getting ambulances to patients or getting power to homes around the country”.


The plan puts the UK ahead of the US, where the issue has been rumbling on since President Bush announced a new satellite resilience plan, and a law to authorise it was passed. Those early moves have not actually produced any results.

President Trump’s White House has just announced a new programme but it appears to be no more than studies for future investment rather than actual projects, according to the Resilient Navigation and Timing Foundation (RNTF), a Washington group campaigning on the issue. The Foundation said the UK plan was a great initiative.

Almost nostalgically for small boat navigators with pre-satnav experience, the UK still operates a ground-based Loran navigation system, though receivers for yachts are no longer available (as far as I know). The RNTF believes that Loran may be expanded and incorporated in the UK timing resilience network, which it thinks will be wireless-based rather than land lines.

Amazing to think how dependent we are on one technology at the moment. Ten years ago we used to worry that the US might degrade the accuracy of GPS or switch it off in a war. That is now inconceivable, so dependent is the entire US economy on it at the moment.

More realistic dangers  include accidental  system failures, as with Galileo, deliberate or accidental interference on a regional or local level, and spoofing. If you think about what some idiot can do with a drone near an airport, imagine the chaos if disruptive forces started jamming and spoofing GNSS. The expertise to do that has been nakedly displayed in recent years in the Gulf and the Black Sea near Ukraine.

Back to earth: as I mentioned in an earlier post, plans are always tentative at this time of year, and so that is proving. The passage to north-west Spain I was writing about in December and January has run into the problem of coordinating two lots of family diaries, which can be tricky with joint ownership and joint sailing plans.

Various unmissable events on both sides now mean shorter periods on the boat this year, so the plans are evolving. Maybe we will go back
to south Brittany, where we spent three seasons recently.  Spring Fever on the River Vilaine, southern Brittany

We could always go down from there to Spain next year. There are so many lovely places on the French coast that it would be no hardship if that is what we decide.

Boat maintenance has been brought back home for me this month, with various canvas repair jobs to do on the safety equipment, sail cover and dinghy cover, plus rope whipping, and also ordering new lifelines and jackstays.

Got a great new  sewing  awl for canvas that is much quicker than a needle and palm..

January – satellite scares, and getting ready for Biscay

At the Royal Institute of Navigation’s small boat conference in Lymington earlier this month, I learnt a lot about  new risks of error  in satellite navigation : I did not know, for example, that it is possible with quite cheap local equipment to fool the GPS on a plane, ship or even a missile into thinking it is somewhere other than its real position.

There are now tens of thousands of reported incidents of errors, deliberate, accidental or of unknown cause, with a substantial number of them unsurprisingly in sensitive areas such as the Gulf, and the Black Sea near Ukraine, suspected to be hostile activity.

Reports of accidental errors include a couple of local failures when US naval vessels arrived in the port of San Diego, apparently forgetting to switch off unspecified electronic equipment, which interfered with satellite-derived positions for miles around.

These are serious issue in defence circles, and of course for boats and ships of any kind near a source of interference or one of the ‘spoofing’ attacks. It is easy to imagine some disruptive force deciding to get hold of the equipment and blocking position-finding in a sensitive commercial area such as near an airport or in a vital shipping lane.

Satellite positions are integral to the operation of every form of commerce, from planes and ships  through mobile phone masts and everyday driving, Amazon deliveries and Uber – you name it and somewhere in the business location finding is vital. So there is increasing pressure to redevelop  an old ground-based system called Loran as backup. Loran has not been switched off, but would now need a lot of development and investment. If you want to know more, look at the website of the Washington-based Resilient Navigation and Timing Foundation.

GPS is just one of five satellite position-finding systems in operation, all now called GNSS (Global Navigation Satellite System). GPS, like the word hoover, is a US name that is in danger of wrongly becoming the label for  a whole range of products.

Other GNSS now running include the Russian GLONASS and the EU’s GALILEO – so in one sense there’s a lot better backup against total failure. GALILEO was completely out of operation for a while last year after operational mistakes were made by its staff. It was only in the start-up phase but the fault  proved that a single system can go down.

The cover of the current 5th edition of Pass Your Yachtmaster

I was at the conference because I have been commissioned to update an excellent sailing book, David Fairhall’s Pass Your Yachtmaster, illustrated with hilarious cartoons by the late Mike Peyton.

Completely coincidentally, the cover of the current edition has a nice but anonymous photo of a Sigma 362, the same model as Spring Fever. Having done 11 seasons polishing and antifouling, I recognise the detail of that bow!

David has updated previous editions of the book, first published in 1982, but asked me to take the baton for the next.  The book is a primer for students doing the Royal Yachting Association yachtmaster exams and tests.

I have to say that re-reading  David’s book and many others on navigation has reminded me of several things I ought to remember, and certainly knew when I did the exam and practical test in the 1980s, but had forgotten, so it’s a good exercise for more than one reason.

Back at the yard, plans for sailing to Spain are firming up so we’re making a couple of small improvements to the boat and some minor repairs. We’ve also booked for the Cruising Association’s Biscay Day in London in March where we will meet others sailing that way.

One annoying issue on Spring Fever has always been the need to lift the anchor from the bow roller a couple of feet along the side of the boat when retrieving it to stow in its locker. I’m always afraid that this is going  to damage someone’s back, holding a 15 kilo weight plus chain at a very awkward angle on a potentially rolling boat.

The reason is that the drum of the Furlex reefing gear almost touches the deck, a feature from the boat’s racing days to maximise sail area, so it blocks the anchor from being lifted straight from the bow roller. We are looking for a rigger willing to shorten the forestay with the mast up, to lift the drum 8 inches so the anchor can be pulled up through the roller, and if necessary lashed and dealt with later. Our usual rigger is not keen because he works alone and it needs two experienced  people, he says.

The sail luff can be shortened at the head because it is very narrow there. Our sailmaker is taking 9 inches off but we will lose only about a square foot of sail area.

We’ve also decided to install a holding tank, so the lavatory can be used when we’re somewhere, er, sensitive to such things eg a marina or swimming bay. Nobody ever asks in the UK or France but Spanish authorities are thought to be more vigilant in checking that boats have holding tanks to store their waste on board, an EU requirement. Very few places have pump out facilities to empty tanks so the usual procedure is to empty them by opening the discharge valves a few miles out to sea.

Spring Fever is ashore this winter at Kingston, the Cowes Harbour Commission yard, rather than at Cowes Yacht Haven, whose prices have been creeping up by the addition of extras. The Haven also focuses on expensive racing boats whereas the Kingston yard, which is very friendly, is mainly full of older boats like ours, so we immediately felt more at home. It is not as conveniently sited, but it is looking like a good switch.

December – thinking about Spain

Spring Fever was taken out of the water on December 16 and put ashore at the Kingston yard in East Cowes, where we are planning to leave her until May. Idle thoughts now turn to planning next year, and to Spain.

We have given up our pontoon mooring on the River Medina for 2020 because we plan to stay away from the Solent for the whole season and it will be cheaper to take a visitor mooring for a few weeks before we leave than to pay a whole year for our own. The conversation is increasingly focussing on the wonderful hills and Rias of North-West Spain, though we do not need to take any decisions for a few months.

Tony has crossed Biscay many times in big ships but neither of us have done it in a 6 tonner, so it requires a bit of research on routes and weather planning, plus the purchase of the pilot book for Atlantic Spain and Portugal.

The whole passage works out at about 600 miles, but it does divide neatly in two if you take the option that goes close in via Finisterre in western Brittany and then direct to a Coruna in Spain. This shortens the Biscay crossing to 300 miles, or two to three days, which is within the period of reasonably accurate weather forecasts, so we can be more confident of not having to cross the steep (and as a result sometimes very rough) edge of the continental shelf in bad weather.

Another option is to head for somewhere like Falmouth or Plymouth and then direct to Spain, crossing the shelf early in the passage, but taking longer, which means information on weather when approaching Spain will be unreliable. That is one serious drawback. Two other things that persuade us towards the Finisterre route are some nice French towns such as Camaret and Audierne where we can wait for a good forecast for the crossing; and the fact that with a short-handed crew – both co-skippers in their seventies – it is probably not such a good idea to do a three or four day passage. (Having written that down, I now remember the Yachting Monthly on my shelf with the account of 77 year-old Jeanne Socrates solo non-stop round the world voyage!)

There is a third route to North West Spain, which is down the west coast of France to the border and along the Spanish north coast, which is nearly as long as Atlantic France. One tentative thought is to come back that way the year after.

It would be good to stay in the EU over the winter of 2020/21 because if we can prove we are there at the end of the transition period in 12 months time the boat will retain its EU VAT paid status and would not be subject to the restrictions of the temporary importation rules for boats from non-EU countries (see earlier posts on Brexit).

The plan is idle winter speculation at the moment, and on past form we may end up doing something completely different from what we discuss at Christmas. But it’s fun to think about it.

There are however some things we really ought to do to make sure we have the option: we ought to fit a holding tank for waste, and we should certainly make some improvements in our anchoring equipment before it causes an injury.

The problem is that the boat was set up for racing, so the Furlex drum is almost touching the deck, which means that the anchor has to be lifted very awkwardly round the side of the boat to lift it back into the well, a recipe for pulled muscles if waves are building.

The drum needs to be raised, which involves shortening the forestay and recutting the foot of the working genoa. That way we can pull the anchor stock through the bow roller and lift it out in a safer way with less risk to our backs, and we also can lash it down to the bow roller if we are in a hurry or reanchoring soon.

November – ocean going on a lake

Looking back at Spring Fever’s logbooks recently to pin down the wheres and whens of a good cruising story, I found they were so sparsely written – professional in the best sense, as they should be with a Master Mariner as a co-owner – that I could not begin to tap them as a surrogate diary. And checking my blog posts each year, I see these have been relatively few, with long gaps between them.

So largely for my own benefit I shall start a monthly diary post, in the hope that in another five years I’ll actually be able to work out what we were up to.

November’s most interesting sailing observation was nothing to do with Spring Fever.
This beautiful 60 foot yacht called Tioga of Hamburg was moored at the end of November at Kressbronn on the German side of the Bodensee, or Lake Constance/Konstanz which is way up the Rhine, near where it starts becoming a mountain river, and well above the navigable section, so cut off from the sea. It is a US  design from 1931 by the great Francis Herreshof, but the original was destroyed and this replica (or so we thought at first from Google) was built in 1988 in Maine and restored in north Germany, where it was recently for sale.

So how on earth did a yacht with those tall masts get to the 38 mile long Bodensee, where Germany, Austria and France meet round the shores? And what on earth would an ocean yacht be used for on a lake where it would take a morning to go from end to end? (A waste of a thoroughbred).


A double check then found a surprising fact: this magnificent yacht is actually yet another copy with the same name, Tioga. It was built in Radolfzell on the Bodensee recently, in 2013, and is for sale for €1.35mn, against a paltry €450,000 for the sea-going 1988 Tioga, which has been cruising the Baltic after crossing from the US.

The question remains: are they really going to sail this lovely wooden yacht just on the Bodensee? If not, how do they get it down the Rhine to the sea? Or do they just stick it on a low loader?
We were actually in Germany on a land yacht of sorts – son Will’s campervan, which had broken down in Austria, and we were on the way home after volunteering to collect it after the lengthy repair. It was fascinating to see how close all the domestic equipment is – including hot and cold water pumps, cooker and gas supply, 12 V wiring, diesel heater, lavatory, shower and bunks – to what you find on a modern cruising yacht.
For Spring Fever, not much happened apart from a decision to winter her ashore from mid-December at the Kingston yard in East Cowes, in reaction to rising costs at our usual Cowes Yacht Haven, which is specialising in the dry sailing of incredibly expensive looking racing boats, whose owners can’t bear dirty bottoms.

We decommissioned Spring Fever on her river pontoon and took the sails, lifejackets etc home, so she is ready to go ashore on 16 December.

This winter we’ve focused so far mainly on sewage! We will finally put in a holding tank after being shamed into it by a massive correspondence on the Cruising Association’s Biscay Forum: I simply posted to ask whether we’d need one for Atlantic Spain, and for some reason it seems yacht owners get more excited in the winter about sewage disposal than any topic other than Brexit. A recent arrival from the US expressed shock and horror to find so many  British boats don’t have tanks. Others deluged us with legal and technical advice.

Tony is boat plumber (I’m electrician) and has visited Tek Tank for a discussion and estimate. We’re finally going to be nice to swim near when we’re anchored in a bay.