It seems that while my phone is accurate to an error of considerably less than 10 metres, the industry is heading to even better precision of a tenth of that level, and soon. This post looks at why that means satellite accuracy on all devices including smartphones is reaching levels where there are diminishing returns for small boat sailors.
In general, 5 metre satellite accuracy has been available on smartphones for a considerable time now. I give links at the end to industry, US government, academic and consumer articles that give more detail on how accuracy has been developing (and see also my earlier post ‘and a phone to steer her by’).
One of the secrets of the top performers such as the high-end Samsung phones, which can achieve 2 metres, is that they now have dual frequency satellite aerials so they can make the best use of the latest improvements not only in the US GPS, but the Russian Glonass, European Galileo and Chinese Beidou satellite systems. Nowadays, phones will often have as many as 40 satellites in the sky from which to choose the best signals.
It’s sad to read happy accounts of a peaceful sailing season just before the worst storm ever unleashed on Europe – by which I mean World War II, not the weather.
I’ve been leafing through the 1938-9 Yachtsman’s Annual, picked up for a few pounds the other day in an Oxfam bookshop. It’s not just the handsome young people in bright sunshine helming racing dinghies, who we know might soon be in mortal danger on the front line in a war. It’s also the international cruises and races, some of them to Germany, with skippers and crews displaying no public awareness (whatever they privately thought) of what was happening in the world around them.
Mobiles have had a bad press as navigational tools, but if I were forced to choose one single piece of electronics to take to sea it would be my phone. That’s not a popular view among professionals.
Instructors, coastguards and rescue services learn of many cases where boat owners, especially of powerful motor yachts and RIBs, set off for the open sea with nothing beyond a chart app on a mobile phone, and no knowledge of the underlying skills needed to navigate safely. For the Royal Yachting Association, mobiles are well down the list of recommended priorities, because of the risk that they will be used badly. Textbooks give stern warnings that you must not use them for navigation.
Summer came back in the middle of October, with sun, warmth, gentle winds from helpful directions, and calm blue seas. Five days sauntering along the Dorset coast under bright blue skies was an unexpected gift at the end of a season of dull weather.
We left Cowes in the afternoon and picked up a free mooring outside Yarmouth harbour for the night in a calm that hardly moved the boat. The next day we went pleasantly to Weymouth in a Force 3 from the land, which gradually built to 4, so we creamed along on flat water, well out from St Albans Head because the army firing range was operating.
But if a yearning seizes you to roil In stormy seamanship, when the Pleiades, Fleeing Orion, sink in cloudy seas, That’s when all kinds of wind blasts rage. Don’t keep Your ship longer on the wine-dark deep, But work the earth, and mind what I command:
Now’s when to draw your ship up on dry land, And pile stones round to keep wet winds at bay. Pull out its bilge-plug, that it not decay With Zeus’s rainfall.
Stow the gear, all things You need for sailing, make sure the wings* Of your seaworthy ship are in good trim. And hang the well-wrought rudder in the scrim of smoke#.
Till sailing season comes, just wait. Then drag your swift ship seawards. Range the freight in its hold, get ready for the profit you’ll Bring home”
From “Works and Days (Penguin Classics)” by Hesiod, 7th or 8th century BCE, trans A. E. Stallings.
* sails or oars. # to preserve it?
A quiet month for sailing, but we’re planning at least one autumn cruise before layup – if the wind blasts don’t rage.
For almost all the daylight hours during our 170 mile passage back to Cowes the sea was a mesmerising blue.
After weaving our way overnight through the sandbanks and brilliantly lit windfarms of the Thames Estuary, there was little to do in the calm of the English Channel except watch the autopilot and check the plotter from time to time.
It was enjoyable in a way that had very little to do with sailing. We did three hours on, three hours off and probably got more cumulative sleep than we usually have in 24 hours at home.
There was one concern during the passage, which was that the fine weather had prompted an unusually large number of refugee boats to cross from France.
We kept a watch for them as we went through the Straits, passing Dover as the sun rose, and saw none, though we did come across a channel swimmer making way at 1.7 knots. (We could tell the speed from the escort boat’s AIS broadcast).
The swimmer doing an impressive crawl.
We heard the coastguard talking to a yacht that had come across a refugee boat, one of a couple of dozen that were later reported to have crossed that day. Coastguard regular VHF broadcasts included requests to report the positions of any boats spotted.
There was no sense that danger was imminent in the case we heard, and the coastguard let the yacht continue on passage once it had reported the position. If it had been rough and the refugee boat was in danger of swamping that would have been another matter, because a yacht would need to stand by a potential casualty until help arrived from the RNLI or Border Force boats.
Only a few weeks previously, the shameless Nigel Farage had launched an attack on the RNLI for running what he called a taxi service for illegal migrants. He may have pleased the far right but thankfully he also prompted a huge increase in supportive donations to the RNLI.
After the Straits, we stayed inshore simply for the views, close to the lighthouse and power station at Dungeness and nearer to Beachy Head than we’ve been before.
There was not enough wind to switch off the engine even once until we arrived on our mooring in Cowes. The two nights were as calm as the days, though cool, with most of the light breeze produced by our own speed through the water. We added a knot to our speed by motor sailing into our own wind.
We chose to go because it was an all-too-brief weather window between south-west and westerlies. Long gone are the days when I’d have seen a 170 mile beat to windward as a challenge, and anyway I would not have dreamt of trying that without a crew of at least four, rather than two-handed.
Within hours of arriving in Cowes at 4a.m. the wind had got up from the south-west, there was driving rain and visibility was down to a few hundred meters, making it a miserable day for the racing boats which were there for Cowes Week.
Luckily it wasn’t the last sail of the month. Had a lovely few days going to Weymouth and back in the sunshine with Robbie.
Not much wind going there but a splendid sail hard on the wind in a NNE 4 from around Lulworth Cove to where we dropped anchor in Totland Bay on the Isle of Wight. We waited there for the tide up the Solent.
Moored in Weymouth
Weymouth was in a holiday buzz, helped by the focus on British holidays this year, and we had a very pleasant time there. We bought fish – prawns as a starter and then fried skate with capers – and both were the freshest I’ve tasted for a long time. The fish shop on the quay said they were from the boats moored outside.
How would wehelp a refugee boat in trouble? The usual advice is not to take people on board. There is an implied threat in that advice – not spelled out – that a skipper could be seen as complicit in illegal entry if a yacht arrives in port with refugees on board. On the other hand, international maritime law obliges ships and boats to try to save any life in danger, regardless of who they are, so quite apart from the instinctive reaction to help there would be a duty to intervene if a boat is swamping and refugees could drown.
It would not be easy to help. We practice man-overboard retrieval from yachts, and in all but calm conditions it takes many minutes to retrieve a practice dummy (usually a lightweight fender), and then there is the even bigger problem of getting a heavy person on board.
The stern ladder is dangerous if there is any sea running and a folding side ladder is difficult and slow for all but the fittest. Our backup method is a crane using the blocks and tackle of an old mainsheet, kept ready in a locker to be hung from the end of the boom, with the rope run to a big winch, a system that we have tested by lifting a 14 stone man.
The most practical way to save lots of people quickly is probably to launch our liferaft and three horseshoe buoys for them, and perhaps some fenders, keeping all the equipment tethered to the boat with lines, while we take the weakest on board as best we can, hoping for the lifeboat to turn up quickly.
There’s nothing quite so much fun as messing around jumping off boats on a hot day.
Here Seb and Xan are having a great time leaping from Spring Fever at The Rocks, a beach on the River Deben where we anchored.
There was a strong tide running, so we set up a rope on a fender and let the dinghy out a long way so there were safety lines to grab.
Those in the picture below weren’t quite long enough, because once Xan didn’t quite make it back to them when he swam away after jumping from the bow. Ben took him down to the next anchored boat where they were helped out of the water and into our dinghy when I arrived.
We doubled the length of the lines and they went on jumping. I joined the fun in another session later in the afternoon. By then the water had reached almost 25 degrees as it ebbed down river after sitting on the mudflats further up.
Ruth had joined us at Ramsholt for a morning away from her work-at-home laptop, and we ferried her ashore to walk back along the river bank. She had a full afternoon’s work to do back at Bawdsey, where she was staying with Caroline – one of the mixed blessings of lockdown is employers’ willingness to let staff work from anywhere with wifi.
Ruth after landing at The Rocks
After swimming, we picked up a mooring at Ramsholt and went ashore for a walk and for drinks with Caroline on the terrace of the idyllically-set pub.
Chris ready to go ashore at Ramsholt
A few days earlier, Indigo and Will were on board with us, and here she is showing her steering skill.
We went ashore and walked a mile to the Butt and Oyster, Pin Mill, for dinner at an outside table. It was high tide, and Chris and Indigo watched horses that had just been exercised in the water.
On the way back we saw the Nancy Blackett, Arthur Ransome’s boat and the model for Goblin, the yacht in which the children accidentally start from Pill Mill and end up in Holland in We Didn’t Mean To Go To Sea. It has been restored and is owned by a trust.
The Nancy Blackett
The previous night was the European Cup final, and we stayed on board to watch England lose on penalties.We had no England flag so used a number 8 signal pennant to stand in for it.
Will then photoshopped a picture of Indigo with our Irish courtesy flag into an Italian flag (changing orange to red) and sent it to the Italian side of her family when they won.
It was still a good dinner! We watched the match on Will’s laptop linked to my phone as a hub.
Children found the size of the container ships awe inspiring as we passed them close by at Felixstowe, but Seb and Xan were much more excited to see the polar research ship the Sir David Attenborough, which is registered at Stanley in the Falklands but whose UK home base is Harwich.
Felixstowe container portBoaty is hiding somewhere
They scrutinised every inch looking for the Boaty MacBoatface, the winner of the national naming competition for the ship. The winning name was hastily switched by the organisers to a research submarine the ship carries, after the competition misfired in a rather splendid way. Boaty must have been stored on the other side, because we couldn’t see it.
After anchoring for lunch further up the Stour we locked in and spent a night in Shotley Marina, where we explored with the boys along the river and also looked at the derelict Royal Navy training college HMS Ganges. There we saw the sadly decayed mast of a 19th century sailing warship once used for recruit training.
The mast at HMS Ganges
You can see from the photo below that half of the top yard has broken off and is hanging down from a rigging wire, the other half has gone and a complete spar is missing lower down. Before closure in 1976, the college featured annually in the newspapers for its graduation ceremony, where cadets perched along the yardarms and the best in class saluted while standing precariously on the 18 inch diameter ‘button’ at the very top. He was called the Button Boy.
The Button Boy is at the very top
Seb and Xan brought their sketch books and relaxed with them later in the saloon.
Below. crew boss Ben, helmsman Seb and cabin boy Xan take charge.
At the end of this cruise, which also featured a walk to Pin Mill for dinner, the water taxi at Woolverstone Marina made packing up and leaving the boat on the mooring a lot easier than it used to be by dinghy. Dinghies are great, but not so much fun carrying a crew, loads of baggage and a week’s worth of rubbish ashore.
Landing in the dinghy atThe RocksBen, Peter and Xan coming back from the pubIn the water taxi, Ben talking to the drivetLeaving Spring Fever on the Woolverstone mooring
The last event of the month was me taking Spring Fever to Suffolk Yacht Harbour at Levington for a bargain summer scrub. We were trailing such huge quantities of weed that with a clean bottom we added a knot afterwards, measured at 2500 rpm on the engine.
Out for a wash
While waiting. I had a lovely 6 mile walk along the banks of the Orwell and back inland (via a pint at The Ship at Levington).
The new, updated and expanded edition of Pass Your Yachtmaster is in the bookshops. It’s the best primer around for the RYA sailing qualification, and the only one with jokes – the serious stuff by David Fairhall and myself is leavened with lots of hilarious cartoons about sailing by the late Mike Peyton.
There’s a new chapter on electronic charts and fresh material on weather forecasting, safety equipment and other aspects of sailing offshore that have been changing in recent years as the technology improves.
We are now pottering happily around the Essex and Suffolk coasts, visiting places we got to know well years ago when we kept our various boats here.
From our rented mooring at Woolverstone on the River Orwell, we went down to the River Colne, spending a night in the Pyefleet, one of the best known East Coast anchorages, just behind Mersea Island. We picked up a mooring buoy rather than having to spend half an hour getting glutinous mud off the anchor next day – worth the £10 we paid to the man from the oyster fishery, who came round on a paddleboard collecting money from yachts.
Finally, we got away, covering 180 miles from Cowes to Woolverstone on the Orwell in Suffolk in one go. Conditions were perfect for a fast passage, with Beachy Head crystal clear in the afternoon sun and the white cliffs of Dover actually shining as we passed in the brilliant light of a full moon.
We abandoned plans to stop in Ramsgate when we arrived off the town at dawn with the tide still under us. We kept going, motor sailing with genoa only because there was hardly any wind.
The virus lockdown rules allow me to drive to the boat from this week onwards, so a day is at last in the diary for moving Spring Fever from her winter berth in Chichester to her permanent mooring in Cowes.
Now we’re hopeful that we might actually make that cruise to the east coast we cancelled twice last year, so I’ve been updating my Thames Estuary charts and pilot book and reminding myself of the different route options around and across the multiple sandbanks between North Foreland and Harwich.
My most recent surrogate for sailing has been to watch You Tube videos from the Sampson Boat Company – an addictive glimpse into a world where something beautiful, functional and powerful is being constructed out of wood, in a project run by an English boatbuilder working in the USA. I highly recommend it to anyone, boat person or otherwise, who wants to wind down from today’s tensions. This is a link. The YouTube viewing figures show that hundreds of thousands of others have found that out too.
Planking the hull of a 1910 Pilot Cutter being completely rebuilt at Sampson Boat. Still from YouTube.
I was intrigued by the equipment list below, which is more than three decades old, because it was a reminder of how long we have been arguing about the risks and rewards of electronic navigation. I found the list in some old files I was checking last year for the sixth edition of Pass Your Yachtmaster by David Fairhall and Mike Peyton, which I was commissioned to update by Adlard Coles*.
A 1989 list of yacht electronics talked about at the Boat Show
The list was part of an article I produced for the Guardian newspaper about electronics for small boat navigation, under the headline ‘And a satellite to steer her by’, researched by talking to manufacturers due to appear at that year’s London Boat Show. I had forgotten all about it.
How accurate is the position calculated by your smartphone? The Royal Institute of Navigation is sceptical. Its new book on electronic navigation for leisure sailors says: “At sea, mobile phone positioning uncertainty will typically be several hundred meters or more, which may be enough to put us into danger”.
I am looking for some proper studies on this issue, because I am sceptical about that statement. In the meantime it’s easy to check what your phone tells you about its own location performance when it relies only on satellite signals.
tide by tide 