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Routing 2b of 7 : Routing planning and optimisation an extra brain as well as a pair of hands…

In my previous posting I listed those systems which were clearly aimed at the racing sailor. This is not meant to be a drawback – it depends what your objectives are as a sailor as well as your capability and skill level. They very accomplished pieces of software and provide at the very least a source of information to the cruising sailor about the higher art of race tactics, tuning and performance.

The next group are NOT inferior to the the first (TableA) in any way -  but I feel that they are less likely to be underutilised by the normal cruising sailor than the ones in the racing stable above. I feel that they may be operated in more of an amateur manner with less fine tuning than the top racing packages. This is a backhanded complmemnt to SeaPro and MaxSea – systems which are very well accomplished on the racing circuit !

It may seem strange to put MaxSea in this table since there are dozens of race wins attributed to it… but it is included as testament to the ease of use of its interface that I believe makes it far more intuitive than the race packages above. It is truly a race class piece of software but it can easily be used by a cruising sailor with its elegant “TimeZero” interface.

The TableB systems can still be fine tuned by a knowledgeable and careful sailor – and of course all these packages still beg the question of how good are your instrument; your sails; your boat and of course You!  – remember GIGO rules :-)

There are other systems out there too like SailRouter (€400 “..calculates the quickest sailing route relative to the weather forecast and sailing boat polar diagram data..”) and  SailFast ($US 249) – that I have not included simply because of time and the lack of information about them other than what is on their web site – I dare say that these too are excellent packages – and may be worth investigating for a complete picture of what’s available. According to the SailFast web site “.. predict optimum routes for offshore racing and cruising. Weather information is imported directly from Grib forecasts of wind, current and sea level pressure. Built-in Gulf of Maine tidal currents are already included…”

 

TABLE B    
ECS/ECDIS Software with optimal routing Publishers description, and feature lists… Provenance…
MaxSea Time Zero Navigator Pack with optional Routing Module

£ 629

 MaxSeaTZ-1 MaxSeaTZ-2 MaxSeaTZ-3 MaxSeaTZ-4
 

Comprehensive racing and cruising software with utilising the Isochron method of route calculation.

  • Route optimization
    • Tides, currents, wave height, frequency, direction
    • Accurate tidal currents
    • Weather
    • Polar functions to output, analyze and create or modify a yacht’s performance polars
    • Data Trend Center gives you an easy-to-use graphic history of wind and performance
    • Performance Data Display gives you constant updates on target wind angles and target boat speeds.
    • Continuously update 3D chart data utilizing Personal Bathymetric
      Generator (PBG) and echo sounder
  • TimeZero UI:
    • TZ look and feel (work spaces and ribbons)    
      automatic full screen feature    
    • Customizable Toolbar, Ribbons and NavData    
      Undo / Redo function    
    • charting engine (seamless, smooth…)    
    • PhotoFusion (photos and charts)    
    • 3D navigation (recording Marks, waypoints & routes, etc.)
  • Unlimited vessel track and track line coloring    
  • Unlimited Marks, waypoints & routes, Marks, waypoints & routes lists    
  • Marks and routes transfer to GPS
  • Worldwide tide database included, US tidal currents included
  • Worldwide planning charts included
    • C-Map / Navionics Platinum (special TZ versions)     
    • One Mapmedia mm3d chart area included (charts, 3D and satellite photos)    
    • Online search engine to localize on chart worldwide places.    
  • POIs: Online Photos Google PANORAMIO compatibility – Adding to “My Photos”.
  • Alarms    
  • Logbook
  • Networking support Furuno NavNet (Ethernet)
  • Free web service weather updates (cloud, wind, waves, currents, pressure), adding Air Temperature, Cloud and Rain-Snow.    
  • Free web service ocean data (SST, sea height anomalies, plankton)

 

“…With more than 35,000 installations, MaxSea is sold in more than 20 countries on five continents. It is available in English, Spanish, Portugese, Danish, Italian, Norwegian, Swedish, Dutch, French, Icelandic, and German…”

“…Long time MaxSea partner, Michel Desjoyeaux shared his expertise to help us develop even more successful and innovative sailing solutions. A fierce competitor is always searching for the most innovative technologies. Michel chose MaxSea Time Zero as his navigation and routing program for The Vendée Globe 2008-2009 race.

Sailing victories :

  • The Vendée Globe 2008, 2009
  • The Route du Rhum in 2002
  • The Vendée Globe 2000, 2001
  • The Solitaire du Figaro in 1992, 1998 and 1997 ….”

..more victories here

Author : Brice Pryszo (& The Team At MaxSea/Furono!) – France

SeaPro 3000 Performance

£940

SeaPro1
 SeaPro2

SeaPro-polar SeaPro-routing1

Comprehensive racing and cruising software with utilising the Isochron method of route calculation.

  • Route optimization
    • Enhance weather routing – taking into account tidal conditions
    • Route will avoid user defined no-go areas
    • Show true geographic wind
    • Polar functions to output, analyze and create or modify a yacht’s performance polars
    • Weather display and analysis.
    • Start display and advanced racing functions
    • Race schedule functions to track and analyze competitors
    • Wind on next leg, laylines, tacking angles
    • Performance meter displays boat speed, target speed, performance %
  • Up to nineteen ‘virtual’ instrument (data repeaters) can be displayed on screen. Each instrument can be configured to give a voice output (English version only
  • Advanced logging features – High performance data logging of your instrument data, allowing monitoring and analysis of your sailing performance
  • Optional world wide database for most of the worlds primary and secondary ports
  • Optional Navionics Platinum and Gold chart reader
  • Supports LIvecharts; ARCS; S57/ENC data from either Primar (Norway) or from the UKHO’s service AVCS; Seafarer – Australian Hydrographic Office Charts; NZ Mariner – New Zealand Hydrographic Office Charts; BSB

For yachts without expensive racing instrumentation, seaPro can provide information such as target boat speed, time to layline etc. Output is provided to interface to dedicated mast displays such as B&G, Silva, NKE and the wireless Tacktick system

“…During the race, knowing exactly where you are and forecasting the weather is a big job. I will have a lot of tools to do this but it often takes 6hrs or more of analyzing each day in order to make the right decisions. For charting, I use all ‘digital’ charts, that is I feed GPS data to my laptop where I am running both Nobeltec navigation and seaPro racing software…”.  Bruce Schwab, who was the first American officially to complete the Vendée Globe in the 2004-2005 race.

Author : Euronav – UK 

 

I wanted to focus on software that had an actual optimal routing calculation function not only “decision support” e.g Grib file overlay and so on… So I have not included the enormously popular and successful packages such as Coastal Explorer which has an excellent Web 2.0 aspect to it with Gazeteers, blogs, community sharing (see review here) and all the very latest ideas on UI design. The system was authored by Brad Christian an ex Microsoft alum. Brad also blogs personally about the use of the software and this is a very strong point for the users of his system.

There are so many very good ECS/ECDIS systems – Raymarine RNS (good Navionics support) ;  Fugawi (excellent chart and data import/export) ; Mapsource (excellent BluechartG2 / Garmin support); Tiki Navigator (now supports Navionics Gold) ; WinGPS4 (with DKW chart builder) ;  not to mention the stupendous value of PolarNavy for only $33 !…

There are also some utilities that are well worth having a look at for added value when calculating and planning a route such as NavTools RouteXP; and Sailplanner for weather routing – its FREE !

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Routing 2a of 7 : Routing planning and optimisation an extra brain as well as a pair of hands...

For the experienced sailor – and the world’s best sailors and navigators all use sophisticated routing and route planning software – this software is a critical source of information , while for the less experienced (like me) it is an education as well.

In the course of this research I have corresponded and talked with a number of the developers of this type of software, and I have been impressed not only by their sailing credentials, and their skill at software development, but also at the care with which they have struggled to meet the challenge of creating viable and trustworthy systems that can add value to the cruising and the racing sailor – without taking away any of the responsibility of a skipper.

It is a very exciting area of sophistication for ECS/ECDIS systems – and I certainly feel that using this type of software – and putting effort into understanding it – will make me a better sailor – I will never be a  Michel Desjoyeaux – but I may benefit from his and other expert’s experience because it is sailors like these that are being consulted in the design and logic of the routing software.

I will be posting my findings in a variety of sections relating to:

a) Data Inputs (wind, pressure, tide, streams, wave etc)

b) Boat characteristics

c) Routing algorithms

d) Charts

e) Conclusion

I really wanted to find some characterisation that would help to distinguish certain systems from others – so I thought I would separate them as follows:

TableA – True racing software which incorporate weather or other optimal routing calculations

TableB – Sophisticated ECS/ECDIS systems which incorporate weather or other optimal routing calculations

I will also list those comprehensive ECS/ECDIS systems – where routes could be created, weather viewed but without specific optimal routing calculations – they certainly can be regarded as “decision support” systems. I will also list some Free / low cost software that could still contribute to routing decision making

The focus of my review are the systems listed in the first two tables – those which incorporate some type of planning and optimal routing calculation.

The first group are out and out sail racing systems. This does not mean that they cannot be used for a round the world adventure or by a cruising sailor. Quite the reverse. But they really deserve excellent inputs – both from instruments and by human judgement and skill. Then they are capable of giving detailed and complex outputs. If you are not in the class of racing sailor and that is not your ambition, then these systems may be “over the top” for you. It would be a shame not to use them to their full potential. They are however the best of the best in achievement, and credibility when it comes to racing.

TABLE A
Racing ECS/ECDIS Software with optimal routing Publishers description, and feature lists… Provenance…

Expedition

$US 1,295

Expedition1
Expedition2
Expedition3

Comprehensive race software with utilising the Isochron method of route calculation.

  • Route optimization
    • Tides and currents
    • Polar functions to output, analyze and create or modify a yacht’s performance polars
    • Weather display and analysis.
    • Start display and advanced racing functions
    • Race schedule functions to track and analyze competitors
    • What if? functionality
    • Buoy racing tasks – instrument calibration, time to mark, start line functions, laylines
  • Chart-plotter that seamlessly rotates, mosaics and moves between charts.
  • Supports C-Map (NT & MAX), Maptech PCX, BSB & Softchart formats
  • Displays marks, courses, Laylines, track and race schedule information on the chart.
  • Simple handicap support.
  • Logging functions to record race data that can be replayed or analyzed later to assist with instrument calibration or polar modifications.
  • Stripchart program to graph any instrument function.
  • Support for AIS receivers.
  • Networking support
  • Interface to Simrad BR24 Broadband Radar
  • NMEA 2000 data (inc. AIS via Actisense NGT-1)
Expedition and its tools have been developed since the 1993/4 Whitbread by veteran Volvo Ocean Race navigator and Whitbread winner, physicist Nick White. Expedition has been used in multiple Volvo Ocean, America’s Cup and Grand Prix events since.

Expedition is continually refined by a core group of world-renowned navigators, including two-time America’s Cup winning navigator Peter Isler…”

Author : Nick White


Deckman v9.1

$US 1,327.95

Deckman

Comprehensive race software with utilising the Isochron method of route calculation.

  • Route optimization
    • Graphical or tabular presentation of optimum route
    • Tidal database for popular areas
    • Optimum routes taking into account land masses
    • Supports standard GRIB* weather files or create your own for wind and current
    • In-built tools for OCENS WeatherNet and Saildocs downloads
    • Compatible with SHOM tidal data (Channel and Biscay) and Local Knowledge Current models
    • Unique reverse routing algorithm to analyze competitor positions and effect of leaving optimum route
    • Polar functions to output, analyze and create or modify a yacht’s performance polars.
    • Wind calibration facilities
    • Calculation of Laylines
    • Windward/leeward course
    • Olympic triangle course
    • Complete predictions for future legs
  • Dedicated start display
  • Tracking competitors and time-on-time handicap calculations
  • C-Map version supports: C-MAP, BSB, Maptech, PCX and REML charts
  • Euronav version supports: ARCS, Livechart, BSB, Maptech, PCX and REML charts
  • Alternatively use any image file as a chart for a powerful planning or analysis tool

The 9.1 update enhances the GRIB (GRIdded Binary format) weather and routing functions, adding the options of displaying precipitation and wave height alongside the existing choices of wind speed and direction, barometric pressure and sea temperature.  By allowing the wave height display to interface with the Optimum Routing function it gives navigators the option to route their boats around areas of waves over a specific height, thereby avoiding seas that could significantly reduce performance or even result in damage.

“…Navico was born as a fusion of two of the leading international players in marine electronics, Simrad Yachting and Lowrance Electronics. With the addition of Brunswick New Technologies’ marine electronics division in March 2007, Navico is truly a house of brands, with the B&G, Eagle, Lowrance, Northstar, and Simrad brands all manufactured and distributed under the Navico umbrella. Deckman is a product of B&G. Deckman is the world’s most advanced tactical navigation software and is used by winners in every field, from sports boats to the Volvo Ocean Race and America’s Cup, the software includes all the tools you need for short course round the buoys racing, long distance offshore and ocean racing…combined with B&G instruments it hard to beat”

Author : originally developed from Sailmath, written by Graeme Winn , Brighton, UK


Advantage

$US 900

Advantage1_th
Advantage2_th
Advantage3_th

Comprehensive race software with unique approach to route calculation. It does not use the Isochron method but its own “Local Knowledge” method.

  • Route optimization
    • Graphical or tabular presentation of optimum route
    • Tidal database for popular areas
    • Detailed hydrodynamic current prediction models by “LOCAL KNOWLEDGE”
    • Supports standard GRIB* weather files or create your own for wind and current
    • Compatible with Local Knowledge Current models
    • Polar functions to output, analyze and create or modify a yacht’s performance polars.
    • Wind calibration facilities
    • Calculation of Laylines plus short range tactics – computation of optimal sequence of tacks
    • Windward/leeward course
    • Complete predictions for future legs
    • Long range tactics – “Advantage” routing function
    • Comparing user defined routes “Course Solution” function
    • Charts primarily from C-Map sources
    • Alternatively use any image file as a chart for a powerful planning or analysis tool using a “Chartmaker” facility

The LK approach to routing employs a fine-scale digital grid covering the sailing area. The times required for a yacht to sail between adjoining points on the grid (either directly or by tacking and gybing) are computed individually in view of the wind and current conditions applicable to that part of the course. These times are then added together in various combinations to construct and evaluate routing alternatives.

The Advantage Software with Local Knowledge data has been used by boats in the Sydney Hobart Race since 2000, the 2009 Big Boat Series in SF,Marblehead-Halifax, and the Newport-Bermuda races. and the 2009 Transpac.

Author : Dave Brayshaw, San Francisco CA


Seatrack

£550

Seatrack winning-tides
Seatrack3
Seatrack4
Seatrack5

Comprehensive race software with utilising the Isochron method of route calculation.

Seatrack is a software package that provides a one-stop, integrated performance, tactical and navigation system in three options – for grand-prix racers, club racers and for cruising yachts.

It provides solutions that maximise efficiency, performance and safety at sea, while being exceptionally easy to use – it has been designed by yachtsmen for yachtsmen

  • Route optimization
    • Advanced Chart Plotting
    • Route Management
    • Tides
    • Virtual Instruments
    • Weather Forecast
    • Performance & Tactical Data Analysis
    • Next Leg Apparent Wind
    • Optimum Routing
    • Polar Management
    • Sail Chart
    • Tactical Planning
    • Target Speeds
    • Target Tracking
    • Winning Tides
    • Handicap Calculator
    • Instrument Calibration
    • Start Line
  • Trend Monitor
  • AIS
“..Seatrack-equipped yachts have recorded a strong run of success over the last two seasons. These include:

  • Cowes Week, overall winners of Classes II and III and the Contessa 32s
  • Round the Island Race, winners of IRC Classes 1A,1C and 2A
  • The North Sea Regatta, overall winner
  • East Coast IRC Championships, overall winner of Class I
  • Dartmouth Week, overall winner of Class I
  • Copa del Rey, winner of IRC Class II
  • Les Voiles de Saint-Tropez, winner of IRC Class B
  • China Sea Race, winner of IRC Racing Division B….”

Author : Peter Schofield, UK

…more to follow…

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Routing 1 of 7 : Planes, cars, boats and autopilots...

921G_Autopilot I have been reflecting on the ever increasing complexity and sophistication of electronics in general, and computer software in particular, in use on the average cruising yacht. It appears that the more we have the more we want and expect. In line with more functionality we also expect better reliability!

There appears to be a small but growing trend to move away from dedicated electronics with embedded software on board – like the dedicated Raymarine or Furuno chart plotters, to consumer electronics – laptops and even smart phones. If you look at some of the conversations on the forums some people admit that there laptop wasn’t made for a marine environment – but nevertheless expect it to work – and expect it to be responsible for critical if not life and death operations.

I am as much to blame – I love to see increasing functionality in software and to experiment with it and use it. The difference is attitude and expectation. I know the technology is fragile, and I am not surprised if it doesn’t work – and when (not if) it fails, I just get on with “plan B” – may be its my age :-)

Don’t get me wrong – this isn’t a “grumpy old man’s” diatribe against the proliferation of electronics or the use of software on board – how could it be, I love all this stuff! …and I have more than most on my own boat :-)

No, what I am trying to get at is that we should embrace new technology, we should use it, and we should let it inform us and improve our sailing and our decision making. But, we should be mindful of the old electrical engineering curse of FRED! – “Frigging Ridiculous Electronic Device”…and be ready at  a moments notice to ignore its failure and get on with sailing.

It was with all this in mind that I have been researching the latest ECS and ECDIS systems that incorporate “Route Planning and Optimisation”. Some of the systems refer to “Weather Routing” and some go further and incorporate weather plus tidal streams plus obstacle avoidance.

This type of functionality is really going to take electronic chart plotting to another level. I realise auto route calculation is not new – but it has come of age. We have already come to accept as normal that a boat on the high seas can get large amounts of information sent to it. We have come to expect as normal the excellent weather forecasting data, and sea state data that the various US government agencies distribute for free on the Internet. We have come to understand the improvements that can be made to raster chart data using the vector approach. and combining not only greater positional accuracy as charts are adjusted using the benefit of GPS – but also how they can be enhanced using 3D modelling and hundreds of thousands of satellite pictures. Finally we are seeing huge advances in the accuracy of bathymetric data, again care of the US Navy and Google agreements, which will improve tidal current predictions as well as the obstacle avoidance calculations.

But it may be wise to ponder for a moment about the state of the art in other industries…

autopilotPlanes are probably the most technologically advanced vehicles that we use every day. They cost hundreds of millions of dollars and undergo the strictest test and maintenance regimes of any piece of machinery in common use. They are flown by highly qualified and professional pilots. However they can still fail from time to time.

On October 7th 2008, a Qantas A330 suddenly lost 650ft in altitude after a fault caused the autopilot to disengage suddenly. Thirty-six people on board were hurt, 12 of them seriously, as occupants were slammed into the roof of the cabin. The pilot regained control, and no doubt flew on manual for the rest of the flight!

autopilot2

If you want to be  disconcerted further, you should cast an eye over these sites and check out the banter between airline pilots today…Just about flying and the Professional Pilots Rumour Network.

In every day use by less qualified “pilots” is the humble car. Again a technological miracle of mass production. These machines so advanced and nearly all have considerable computing power on board. As advanced and reliable as they are (when was the last time you even looked under the bonnet!) they can still fail from time to time.

In January 2010, we witnessed the spectacle of the president of Toyota Cars having to hand a formal apology to the Prime Minister of Japan for his company’s failure to spot a fault with the Prius causing a Toyota worldwide recall for a software upgrade to the anti-lock braking system. Akio Toyoda, told the US Congress that “we pursued growth over the speed at which we were able to develop, I regret that this has resulted in the safety issues described in the recalls we face today…”

I am using the phrase autopilot thinking of what sophisticated autopilot systems can do on an aircraft, not the autohelm products that we currently see sold as “autopilot” in the marine business.

Perhaps at some point in the future a sophisticated marine autopilot system will take into account weather, routing preferences, craft characteristics, fuel consumption, time constraints, crew capability and preferences and many other relevant parameters to intelligently pilot a boat.

Where we are at the moment is we have equipment that will autohelm and we have software that will calculate “optimal” routes…. the creation of a truly sophisticated autopilot is perhaps, just around the corner.

I have been researching the latest ECS and ECDIS systems that incorporate “Route Planning and Optimisation”.

Lets be clear, none of the creators of this type of software would dream of classing their software as “autopilot”. But if I may put words in their mouth I think they would regard these very sophisticated ECS / ECDIS systems as a valuable addition to the crew – more of an “Autocrew”.

..watch this space for the results of my research into route planning and optimisation software….

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Update your Wiley Almanac - great, but could it be better?

Wiley0

If you are an English Channel sailor and you haven’t already downloaded the Wiley Almanac application then I highly recommend you do so straight away! The application is based on the Adobe AIR technology so it will work on most laptops and PC’s with very little fuss. The Wiley Nautical Almanac is a free being supported by some reasonable and relevant advertising. It contains a comprehensive directory of harbour, tidal and weather data for cruising sailors. You can refer to the almanac while off line and it currently covers the South and East Coast of England from Lowestoft to Padstow and the continental coast from Vlissingen to L’Aber-Wrac’h.

Wiley1 The Editor of the almanac is Neville Featherstone, who is also the author of the West France, The Channel and North France and Belgium Wiley Nautical Cruising Companions, and the Reeds Almanac too! There is also a paid subscription to get the weather forecasts delivered to your phone – but I don’t really see the point if you can get on the web using your phone or laptop and get a forecast for free. Anyway my overall impression of the content as well as the execution of this service is excellent – well done to Wiley.
When you go online you can download information and update the almanac.
Wiley3 I think the resource could be made even better by the addition of two features – both to do with improving the currency of the pilotage and facilities information, the depth of knowledge, and the accessibility. I think Wiley should consider adding two options to the tab menu:

1. Skipper DB (a personal database of local knowledge, hints, tips, aide memoir stored on the users laptop/pc – indexed to the ports or to markers on the chart – private and not for publication)

2. Wiki (as above but posted on a central database held by Wiley and distributed by their current update system)

  • Weather display
  • Printable weather forecasts and tide tables

    FREE marine weather forecasts for the whole of UK – inshore, offshore and inland. Forecasts include wind speed, Beaufort scale, wind direction, gusts, rainfall, cloud cover, air pressure for every 3 hours Choose and set up your own default forecasts so that you get exactly what you want. You can print out your forecast to take on passage.

  • Of course its difficult for an established and respected publisher to stray too far from the accepted practice of checking provenance of content, peer reviews from professionals and experts and so on…BUT – have courage Wiley – have a look at the excellent Active Captain system.Active Captain is a system that I have written about before – has just been going from strength to strength. It is focused on navigation and pilotage using the iPhone (or at least a modern smartphone) but its reputation and its content is being built on the contribution of hundreds of “Captains” around the USA particularly, but also Captains from around the world…me for example!.

    Within Active Captain there is an “Interactive Cruising Guidebook” tab. This gives free access to over fifty thousand marinas, anchorages, local knowledge markers, hazards, and reviews. And the data continues to grow every day. They claim to be averaging over 1,000 updates each day, 7 days a week, 365 days a year. The system contains the excellent free charts resource from the NOAA. It also uses Microsoft Virtual Earth for the map and satellite images (rather than Google). Recently they have teamed up with MaxSea and you can now use their data together with the MaxSea Time Zero charting software.

    Wiley2 Why is local knowledge useful?If you take a simple pilotage – entering Brighton Marina for example – couldn’t be simpler – but – using Active Captain I have been able to insert a marker showing that there is a tricky if not dangerous moving sand bar and also confusing seas in certain conditions that really could make an entrance dangerous. This information appears no where else, or is buried too deep within the content of the conventional almanacs such as Reeds, or Wiley, and it certainly does not appear on the Brighton Marina website… now, that information is available to anyone approaching Brighton who has looked at the ActiveCaptain web site.
  • Extended tidal stream coverage including the Channel Islands
  • Tides for 2010
  • Information on pilotage
  • Information about facilities at hundreds of ports
  • The advice and wisdom of local sailors is invaluable when entering uncharted waters, or unfamiliar ports and anchorages. I think all these almanac product must succumb to the type of Wiki style update facility that Active Captain and the World Cruising Wiki have has already embraced with such success.Motivation to share knowledge could be provided by a points scheme where accumulated points could be redeemed while purchasing products – Wiley publications for example!

    The style of online publication exemplified by ActiveCaptain will succeed in taking ActiveCaptain from zero to worldwide coverage in a couple of years – while conventional publication methods will struggle to maintain market share, currency, and coverage – perhaps unfairly.  It is great to have the authority of a professionally written, and properly edited almanac – nothing is more reassuring when passage planning in unfamiliar waters BUT why cant the two methods of publication co-exist?

    Now…. lets see if I can load the Wiley Almanac on to a Windows Mobile smartphone….:-)

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    What's your Magnetic Variation - the compass not you !

    Mag1Sitting at home staring out at the rain on a wet and windy Sunday in East Sussex while planning our trip to the Channel Islands this summer, it occurred to me that I dont really pay that much attention to magnetic variation since the variation is so small that it normally doesnt make much of a difference especially when you factor in all the other ways in which either my navigation, my estimation or the various real vagaries of wind, tide and so on affect a course and an eventual landfall. I guess it would make a real difference on an ocean passage but that wont concern me this year – unfortunately:-)

    …..Click here to continue reading →What’s your Magnetic Variation – the compass not you ! »

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