October 2016 – Salty John : The Blog

A vessel moving close to the bank of a river, a cut or a canal will find the stern tends to move towards the bank. This effect is due to the water being squeezed between hull and land, increasing its rate of flow and creating a low pressure area which the hull is sucked towards. I was blissfully unaware of bank effect until I set off from Houston to New Orleans by way of the Gulf Intracoastal Waterway.

In my case, however, it wasn’t the tendency of the bank to suck my little yacht towards it that was the problem; it was the tendency of the huge triple wide ‘tows’ to suck my little yacht towards them – a potentially fatal variation of the bank effect – that had me worried.

This particular stretch of the Gulf ICW is extremely commercial; leisure boats are rare, a minor irritation to the waterway’s regular traffic. One foggy morning we had pulled over to the side of the waterway to keep out of the way of the barges until visibility improved. The bank was grassy and too high to climb but a small sapling overhung the canal and I was able to get a bow line on it – or should that be bough line? The boat lay comfortably against the bank whilst we sipped coffee and waited for the fog to lift.

A booming fog horn indicated the imminent arrival of the morning’s first traffic and shortly thereafter the grey outline of a lumbering behemoth appeared, moving through the gloom some 30 or 40 feet abeam of our snug berth. As the monster triple-wide tow thundered past we found ourselves in the hitherto purely theoretical low pressure area between bank and barge. We were sucked towards the barge at a frightening rate until we were hanging perpendicular to the bank clinging tenuously to our sapling. Oh how I begged that little treelet to maintain its grip on the soil.

As the thousand-foot long iron wall of interconnected barges rumbled past, the sapling bowed and stretched, its immature foliage dipping underwater. Two minutes later, an eternity it seemed, the barge had gone and we settled back against the bank.

Bank effect sucks, I can tell you.

Everyone loves a sunset. Sailors are particularly privileged because we get to see the sun setting over the ocean even on eastern facing coasts, as long as we’re a few miles offshore. Ocean sunsets bring with them the extra tingle of excitement that comes from anticipating the green flash – the fabled emerald green glint on the horizon just as the sun disappears below it.

I have hundreds of pictures and miles of film of sunsets; in none of them is the green flash present. But I have seen the green flash several times. Maybe it’s in the eye of the beholder.

Some people will go to considerable trouble to see the sun go down – the chap standing on the spreaders has a grandstand view. The picture was taken at Boot Key, Florida.

There are several ways to get the cables from your deck stepped mast into the boat without allowing water in with them.

Deck plugs are inclined to corrode and fail unless meticulously maintained. Deck glands are a better choice because any joint is made below decks. Both deck glands and deck plugs are vulnerable to being stepped on by crew working the busy area around the foot of the mast. If you use them, buy metal not plastic versions. A swan neck is a popular choice on bigger boats but they can snag sheets and halyards if you’re not careful.

An excellent option is the Swedish designed Cableport.

The Cableport is a polished stainless steel entry port that takes electrical and communication cables through the deck via a 49mm shrouded opening.

Cableport can take 6 cables up to Ø12mm, or more of smaller diameter. It can accommodate connectors up to Ø 45mm. (A typical PL259 radio connector is Ø 20mm)

It can be easily opened to remove cables and connectors when the mast is unstepped or when wiring changes are made. (No silicone or other sealant is required after initial installation).

Cableport does not catch rigging and lines and can be stepped on without damage.

It measures a compact 160mm x 100mm x 45mm.

The Cableport is available from Salty John – there’s a link over there on the right.
American customers can buy in UK pounds and there will be no additional shipping charge to anywhere in USA or Canada.

The Beaufort Scale of Wind Force has been around for over 200 years; it’s still used in the BBC shipping forecast, issued by the Met Office on behalf of the MCA. You don’t hear much of it across the pond in America, though, or Down Under.

When Sir Francis Beaufort first devised the scale in 1805 it was simply his assessment of the wind strength, based on the observed sea conditions, so that a mariner could decide how much sail to carry. It was intended to describe the conditions under which various amounts of sail could be carried by a man-o-war, the principle warship of the time.

The scale ran from a Force 0, dead calm, in which all sail would be flown, to a Force 12 in which the winds were ….such that no canvas could withstand.

In 1831, when anemometers had been around a bit, wind speeds were applied to each of Sir Francis’ 13 levels of wind force. A Force 6 was described as a fresh breeze of 22 to 27 knots …or that in which a well conditioned man-o-war could carry, in chase, full and by, single reefed topsails and top gallant sails.
Very useful if you know your top gallants from your tam o’shanters.

Over time the scale was further modified and modernised. Wind speeds were added and a ‘state of sea card’ was produced bearing photographs of the sea state to be expected for each Beaufort force. Further Forces were added to cover the conditions that might prevail in tropical cyclonic storms. Wave heights are now seen on many versions of the scale.

The wind speeds which were applied to each of the Forces were, presumably, those that most closely related to the conditions that Sir Francis described. For instance F0, dead calm, is given a wind speed of less than 1 knot, something of a no-brainer, but F5 is 17 to 21 knots – it must have taken some serious debate to arrive at that range of figures. And, inevitably, the progression of wind speeds up the scale is not linear, reflecting the exponentially increasing force on the sails as the wind speed climbs. F5 is 17 to 21 knots, whilst F10 is 48 to 55 knots – as we see, an F10 is not merely twice an F5.

The Beaufort scale is seen as an anachronism by many sailing newbies. There is a temptation to assume the Beaufort scale is simply an illogical grouping of wind speeds with no obvious conversion rate to anything else. Why not, they might think, devise some logical groupings: 0-9 knots, 10 -19 knots and so on, if it’s necessary to group wind speeds at all. Such logic is all very well if you think of Beaufort Force as simply another form of wind speed measurement such as knots, miles per hour or meters per second, for which there is a mathematical conversion.

But that isn’t where it came from; it might have been diverted to that use, but what Sir Francis Beaufort devised was a means of establishing the force of the wind by looking at the sea, a reference source to tell mariners how much sail to risk in any given condition.

And still today merchant ships at sea determine true wind speed from sea conditions – and they supply this information to the MET office. The reason they do this is that anemometers mounted on large fast moving ships don’t tell the true wind speed, they measure apparent wind speed – the wind speed modified by the ships own, often very high, speed and by the effect of the ships superstructure. To get the true wind speed they rely on their deck officers who are skilled at estimating it from the sea state. Sir Francis Beaufort would be proud of them.

My favourite philosopher is Anonymous, or Anon as he’s known to his friends. He’s the bloke who said: The final test of fame is to have a crazy person imagine he is you.

It was another of Anon’s pearls of wisdom that sprang to mind as I was pondering how the cruising boat has changed over the past thirty odd years, trying to keep an open mind, trying to see the positive benefits of new materials and designs:
Don’t limit a child to your own learning, for he was born in another time.

When I dreamed of setting off into the wide blue yonder I followed the teachings of the Hiscocks, the Pardeys and Bob Griffith. My boat would be simple, rugged and seaworthy. It would carry stout ground tackle, fly hanked-on sails and be worked from the deck not the cockpit.

And that’s pretty much how it was. Adriana was 33’ overall, heavy displacement, a simple sloop rig, boom gallows, a massive bronze windlass to handle the all-chain rode and CQR anchors. She was classically pretty, (being from the board of Phil Rhodes she could hardly be anything else), with long overhangs, sweeping sheerline, wide decks and cramped accommodation.

We planned to navigate by dead reckoning with a compass and a set of charts. We carried a plastic sextant for when we were out of sight of land. Fortunately, GPS became available and affordable at about the time we cast off so my astronavigation was never seriously tested.

We had a shiny new Yanmar diesel engine and this begat a battery bank and a big alternator and this in turn begat a fridge to keep the beer cold and the veggies crisp.
This could have been the thin end of the wedge, or as my mate Anon would have it: If the camel once gets his nose in the tent, his body will soon follow.

But no, for this long term cruise we managed to stave off any further adulteration of the hair shirt cruising ethos and had the adventure of our lives. After all, as Anon is fond of saying: Footprints on the sands of time are not made by sitting down.

Anon’s camel did shuffle a bit further into the tent when we set off again a few years later – the boat was bigger and the “keep it simple” principle somewhat further eroded by watermaker, forward-looking sonar, radar and wind generator.

The bigger boat served us well but the watermaker, radar and sonar didn’t make it. They failed to live up to their billing: The watermaker didn’t make water, the forward-looking sonar didn’t look far enough forward and the power-hungry radar didn’t earn its keep. I’ve always seen this as justification for my continuing view that avoiding unnecessary complications on a cruising boat is the way to go despite the current obsession with all things electronic, high tech and led aft.

Of course, my failure to keep what would now be considered essential equipment fully functional is addressed by Anon in one of his more profound thoughts: The man who can’t dance thinks the band is no good.

A great little thinker is old Anonymous.