O C E A N  T H E O R Y

Ocean Theory and Long Distance Sailing

Sailing long-distance is a dream for many yacht skippers, and is – surprisingly – more attainable than you might think.

My interest in it was sparked when I had just bought Aztec, and my friend Eddie made a chance remark that "You could go anywhere in the world with that boat." That got me thinking, and within a few months I was planning what I might do if I took a year off work ...

What you Need

You need to extend your theory knowledge. When you first learned to be a skipper, you learned about charts, tides and weather etc as they applied to coastal sailing in your part of the world. While all of this is still very relevant, you now need to learn about:

•  long distance navigation

•  world climate.

You also need to know some more practical things, such as:

•  getting the yacht ready for long distance / long term sailing

•  communication

•  ocean passage-making.

Reeds Ocean Handbook will provide a lot of information on all of this, as well as references to more detailed information resources you may need (such as world pilot charts). It will act as a useful practical guide as you go through your preparation for a long-distace trip.

It is also a useful companion to the RYA's Yachtmaster Ocean course, if you decide to do that.


Book Overview


The first section is on world climate. It explains:

• the wind systems in the different oceans

• local winds in different parts of the world

• ocean currents

• how and where tropical revolving storms (typhoons / hurricanes / cyclones) are formed, and how to avoid them


This is the knowledge you need for route planning, i.e. where and when to sail.


The next section explains about ocean navigation. The navigation theory you have already learned still applies. However there are other things that you need to know for ocean passages:

• different chart projections that are better for showing great circle routes

• magnetic variation and deviation on long passages

• time zones and longitude

• satellite navigation systems (GPS, GLONASS, Galileo)

The section on astro navigation (using a sextant)takes a realistic, practical approach for navigators whose primary tool is GPS.

It is wise to have astro as a 'fall-back' option for position fixing if your electronic navigation fails, but realistically, most people will rarely if ever need to use it in earnest.

The book explains:

• the principles of astro navigation

• how to use a sextant to take sights.

• how to perform sight reduction using 'pencil and paper'. (It is assumed that if the GPS has failed, this is the surest option for a fall-back method.)

• method uses the 'concise tables' contained in The Nautical Almanac (the essential reference that you need to carry for any astro navigation). No other tables are needed.

• the book gives clear, step-by-step instructions, to make the process as easy as possible to follow.

• the book uses its own one-page astro navigation form, which can be downloaded here.

The following sections focus purely on the practical. First there is a section on preparing the yacht for long distance and long term cruising. This includes:

• sails and spares, downwind rig with two headsails

• self-steering

• electrical power generation and usage

• water making and storage

• general checks, spares and tools

Communication gets its own section. This will help you to select from the different options, which include:

• VHF radio: line-of-sight only

• mobile phone: coastal access

• HF SSB radio: talking to other vessels, weather fax, ship-to-shore telephone

• satellite telephone: phone and basic internet

• satellite broadband: top end solution

Passage making covers:

• planning for an ocean passage

• preparation (food, water, gas)

• on-passage routine: includes navigation tasks, and crew organisation and wellbeing


Heavy weather and storm tactics are also covered, in their own section.


Preparation for emergencies covers:

• medical/accident: prevention of accidents and medicines to carry

• other emergany scenarios: fire, flooding/sinking, structural failure of yacht, man overboard

• assistance and rescue

• survival


To Buy This Book

You can buy this book from Adlard Coles Nautical (part of Bloomsbury), or from Amazon, or from any good bookshop or chandlery (complain if they don't have it!)



Preparing for Long Distance Sailing

The extraordinary thing about our planet is a) that two thirds of it is covered in water and b) that nearly all of the water is joined up. So it you have your own sailing boat, you can make your own way to a huge proportion of the places on the planet, and you get almost unlimited range by using the wind. If you are used to coastal sailing, the incredible fact is that the world is, literally, just out there, beyond the horizon.

The water you sail on is the same as the sea off Africa, the Pacific – and so on. It’s got to be worth learning how to go further!

Hopefully Reeds Ocean Handbook will help you to plan the trip and prepae the yacht. Indeed many books have been written on this: both ‘how to’ books, and of course people’s experiences and adventures. I found ‘Ocean Cruising on a Budget’ to be immensely valuable – highly recommended. (Possibly the worst example to follow is ‘Desperate Voyage’ by John Caldwell; a wonderful account of one of the most ill-planned and naively-executed single handed sailing voyages ever made. Brilliant read!)

Let’s assume that you have reached a level of competence and confidence sailing in your ‘home ground’, and that you are familiar with the theory on this website up to Yachtmaster Offshore level. To continue improving competence and confidence, you do have to push your limits a bit: it’s a very good idea to build up your experience of longer coastal/offshore passages, perhaps overnight or even two nights. This can be done within the scope of what you already know. Sooner or later you are going to encounter heavier weather, and it is not irresponsible to go out in a stronger wind to practice. Just make sure that you, and your crew and yacht, are properly prepared, and you have in your mind a clear fall-back plan for emergencies. This is hugely beneficial. (You can always take a more experienced skipper with you on the first few occasions.)

As regards the additional theory knowledge you need for long distance / ocean sailing, Reeds Ocean Hanbook has a huge amount of useful information and is an excellent starting point.

There is also a shorebased training course available from the RYA: Yachtmaster Ocean, which you can attend but there is no compulsion to do so. Use it if it suits you. Reeds Ocean Handbook covers all the topics in the course syllabus.


Yachtmaster Ocean

Shorebased Course

The RYA provides a shorebased course called Yachtmaster Ocean, which I have instruced a number of times.

It includes a lot on Astro Navigation – the official syllabus contains more than the average GPS user, using Astro simply for a back-up, actually needs. (The material in Reeds Ocean Handbook is actually sufficient, because it enables you to do any astro sight.)

The course also covers satellite navigation systems; great circle sailing; meteorology; passage planning; passage making; and communications. It's a bit light on the practical side - for example, it doesn't cover yacht preparation.

On successful conclusion of this course you receive, as with other courses, a Course Completion Certificate (which isn’t a ‘qualification’ or evidence of competence – merely evidence that you have done the course).

YMO Qualification

The RYA has also set up a qualification called Yachtmaster Ocean, which is gained by:

• completing a ‘qualifying passage’ on a yacht, of over 600 miles / 96 hours, at least 50 miles from land for 48 hours or 200 miles; either as skipper, or in a responsible role in the planning, preparation, and during the passage.

• completing work at sea which shows that they have successfully navigated a yacht at sea by astro navigation. Both of the above are assessed by submitting written records to the examiner. The examiner then conducts an oral test.

• In addition you need either a course completion certificate for the Yachtmaster Ocean Shorebased course: or, alternatively, you can take a written exam on astro navigation and meteorology.


Experience comes first

It is important to recognise the over-riding need for experience if you want to improve your sailing ability, and this is never more true than with ocean sailing.

You do not have to possess a Yachtmaster Ocean qualification before you can skipper an ocean passage; on the contrary, you are supposed to skipper at least one ocean passage before you get the qualification. This may be a surprise to some (surely you should gain the qualification before skippering a long passage?) but this is 'grown-up' sailing, and in order to get the qualification you are expected to build up your own experience.

(Perhaps you will be surprised to learn that, in flying training, you are expected to fly around to different airports, on your own, before you get your licence ...)

So in practice, you can go anywhere in the world without a Yachtmaster Ocean qualification, and of course hundreds of sailors have, and are. (It probably won't be long before you have more experience than the average examiner...)