Launch offer — valid today only

📄 Digital book in PDF · read it on your phone or print it

Offshore Skipper Theory Illustrated: Chartwork, Tides and Rules in Drawings Every Calculation in the Same Order

For Coastal Skipper / Yachtmaster Offshore shorebased theory. Three-point fixes, running fixes, tidal diamonds, course to steer, secondary port heights, IRPCS lights, IALA A buoyage and the Shipping Forecast. Each topic has its own page: the drawing first, then what you need to remember. 73 illustrated pages.

START STUDYING THIS WAY

🔒 Secure checkout · PDF by email · 30-day guarantee

Every topic, its own pageEvery fix and tidal calculation drawn on the chart, with the explanation alongside
73 illustrated pages9 parts, from the latitude scale to the exam-paper checklist
Up-to-date sourcesIRPCS as applied by MCA MSN 1781, IALA Region A and Met Office Shipping Forecast terms
PDF by emailFormat

Look Inside the Book

Every page has one large drawing and a box with the steps and numbers you need to know:

1 minute of latitude = 1 nautical mile = 1,852 m: measure on the side scale.
1 minute of latitude = 1 nautical mile = 1,852 m: measure on the side scale.
Three objects about 60° apart, beam bearing last, fix at the corner nearest danger.
Three objects about 60° apart, beam bearing last, fix at the corner nearest danger.
Tidal diamond: HW at the standard port, hour, direction °T, spring and neap rate.
Tidal diamond: HW at the standard port, hour, direction °T, spring and neap rate.
Six steps on the curve: HW 5.2 m, LW 0.8 m, HW +3h → 3.0 m
Six steps on the curve: HW 5.2 m, LW 0.8 m, HW +3h → 3.0 m
IRPCS: Parts A–F, Rules 1–41 plus Annexes, applied in the UK by MSN 1781 Amendment 3 (2023).
IRPCS: Parts A–F, Rules 1–41 plus Annexes, applied in the UK by MSN 1781 Amendment 3 (2023).
IALA A: red can to port, green cone to starboard, entering from seaward
IALA A: red can to port, green cone to starboard, entering from seaward
Imminent = within 6 h · Soon = 6–12 h · Later = over 12 h
Imminent = within 6 h · Soon = 6–12 h · Later = over 12 h
Step up, not down: liferaft, grab bag and a 406 MHz EPIRB or PLB registered to you
Step up, not down: liferaft, grab bag and a 406 MHz EPIRB or PLB registered to you

Swipe to see more →

These are real pages from the book. The table of contents is the full one: 9 parts and 68 topics.

The Problem Isn't You. It's How It Was Explained.

It's Tuesday evening, the practice chart is open and the question gives you tidal diamond C, two hours after HW at the standard port, springs. You're looking at a little table of numbers and you don't know which row to read.

The course notes explain it in one long paragraph: standard port, hours before and after, direction in degrees true, spring and neap rates, interpolate when you're in between. All correct, all in a block of text, and none of it on the chart.

Tidal diamond: HW at the standard port, hour, direction °T, spring and neap rate.

In the book, the tidal diamond is one page. The table is drawn with an arrow to each part: HW at the standard port, the hour row, the direction in °T, the spring rate and the neap rate, then one worked example read across a single row.

Every other topic gets the same treatment: the three-point fix, course to steer in four steps, secondary port heights, the light arcs of the IRPCS, cardinal marks read like a clock.

You read the diamond, draw the tide vector and carry on, without going back to the notes to check which column was springs.

COMPARE FOR YOURSELF

The Same Topic, Two Ways to Study It

THIS
  • The textbook: line after line of text
  • Fixes and bearings explained only in words
  • You sit the exam paper still unsure
To obtain a three-point fix, the navigator should select three identifiable charted objects whose bearings intersect at approximately sixty degrees, avoiding objects which lie nearly in line. Bearings are taken with the hand-bearing compass, the object nearest the beam being observed last, since its bearing changes most rapidly. Each bearing must be converted from magnetic to true, allowing for variation, before being plotted. The resulting triangle, or cocked hat, should be small; the position is taken at the corner nearest to danger.
FOR THIS
  • The three-point fix in one drawing
  • The five steps in one box
  • You see it and it makes sense
Three objects about 60° apart, beam bearing last, fix at the corner nearest danger.
CONTENTS

Take a Look at the 9 Parts and 68 Topics

The chart and the compass, fixing your position, tidal streams and course to steer, tidal heights and secondary ports, the collision rules, buoyage and lights, weather and passage planning, safety and seamanship, and exam revision: 73 pages, all illustrated.

IThe Chart and the Compass · pp. 6-12
  1. Distance: Always the Latitude Scale
  2. Reading Depths and Heights on the Chart
  3. True, Magnetic, Compass: One Rule
  4. Deviation and the Hand-Bearing Compass
  5. Speed, Time, Distance and the Six-Minute Rule
  6. Plotting Symbols That Keep Your Work Readable
  7. GPS, Waypoints and Chart Datum
IIFixing Your Position · pp. 13-19
  1. The Three-Point Fix in Five Steps
  2. Transits: The Position Line With No Compass Error
  3. DR vs EP: What Each One Includes
  4. Leeway: Which Way to Apply It
  5. The Running Fix, Step by Step
  6. Rising and Dipping Lights
  7. Depth Contours and Radar Ranges as Position Lines
IIITidal Streams and Course to Steer · pp. 20-26
  1. Reading a Tidal Diamond
  2. Using a Tidal Stream Atlas
  3. Course to Steer for One Hour: Four Steps
  4. Ground Speed and ETA From the Same Triangle
  5. Course to Steer Over Two or More Hours
  6. From Water Track to Compass Course
  7. Cross-Channel Passages: Let the Tide Cancel
IVTidal Heights and Secondary Ports · pp. 27-36
  1. The Tide Vocabulary on One Page
  2. Height of Tide at a Given Time (Standard Port)
  3. Time for a Given Height (Standard Port)
  4. The Rule of Twelfths and When It Lies
  5. Secondary Port Times: Interpolating the Differences
  6. Secondary Port Heights: Interpolating the Differences
  7. A Secondary Port From Start to Finish
  8. The Solent: Special Curves
  9. Clearance Under the Keel
  10. Clearance Under a Bridge or Power Line
VCollision Regulations (IRPCS) · pp. 37-50
  1. How the IRPCS Are Organised
  2. Lookout, Safe Speed and Risk of Collision
  3. Action to Avoid Collision, Narrow Channels and TSS
  4. Overtaking, Head-On and Crossing
  5. Two Sailing Vessels: Rule 12
  6. Who Gives Way to Whom: Rule 18
  7. Restricted Visibility: Rule 19
  8. Light Arcs: The Basic Geometry
  9. Power-Driven and Sailing Vessels at Night
  10. Towing and Pushing
  11. Fishing and Trawling
  12. NUC, RAM, Constrained by Draught, Pilot, Anchored, Aground
  13. Sound Signals: Manoeuvring and Warning
  14. Sound Signals in Restricted Visibility
VIBuoyage, Lights and Pilotage · pp. 51-57
  1. IALA A Lateral Marks
  2. Cardinal Marks Read Like a Clock
  3. Isolated Danger, Safe Water, Special and Wreck Marks
  4. Decoding a Light Characteristic
  5. Sectored Lights, Leading Lights and Port Signals
  6. Clearing Bearings and Pilotage Notes
  7. Entering a Harbour at Night
VIIWeather and Passage Planning · pp. 58-63
  1. The Shipping Forecast: Words With Exact Meanings
  2. Depressions and Fronts
  3. Sea Breezes, Land Breezes and Fog
  4. Wind Against Tide and Tidal Gates
  5. Passage Planning: Appraise, Plan, Execute, Monitor
  6. Night Passages, Watches and Fatigue
VIIISafety and Seamanship · pp. 64-69
  1. The Safety Brief Before Leaving
  2. Man Overboard
  3. Distress Calls: VHF and DSC
  4. Abandon Ship, Liferaft and EPIRB/PLB
  5. Fire, Flooding and Helicopter Rescue
  6. Engine Checks and Anchoring
IXExam Revision · pp. 70-73
  1. The Chartwork Order on One Page
  2. The Tides Order on One Page
  3. Night Lights and Shapes: Quick Self-Test
  4. Exam-Paper Checklist

One Page, One Topic, All Clear

Think of it this way:

It's the exam paper, chartwork question: get from the harbour entrance to the waypoint in one hour, with the tide setting across your track. The clock is running and you need a course to steer.

You open the page on course to steer for one hour and see the triangle drawn on the chart: ground track, tide vector, boat-speed arc, water track, four steps in the order you'll use them.

IRPCS: Parts A–F, Rules 1–41 plus Annexes, applied in the UK by MSN 1781 Amendment 3 (2023).

Same with secondary port heights, the running fix, Rule 18, cardinal marks and the Shipping Forecast terms: each one on its own page.

Offshore Skipper Theory Illustrated is 9 parts and 68 topics, all drawn, and it ends with a revision section: the chartwork order and the tides order on one page each, plus a night lights self-test.

What you see drawn, you don't have to memorize.

What's Inside Offshore Skipper Theory Illustrated:

Ipp. 6-12

The Chart and the Compass

Distance on the latitude scale, depths and heights, true-magnetic-compass, deviation, the six-minute rule, plotting symbols, GPS and chart datum.

IIpp. 13-19

Fixing Your Position

The three-point fix, transits, DR vs EP, leeway, the running fix, rising and dipping lights, depth contours and radar ranges.

IIIpp. 20-26

Tidal Streams and Course to Steer

Tidal diamonds, the tidal stream atlas, course to steer for one hour and over several, ground speed and ETA, cross-Channel passages.

IVpp. 27-36

Tidal Heights and Secondary Ports

The tide vocabulary, standard port heights and times, the rule of twelfths, secondary ports from start to finish, the Solent curves, clearance under the keel and under a bridge.

Vpp. 37-50

Collision Regulations (IRPCS)

How the IRPCS are organised, lookout and safe speed, Rules 12, 18 and 19, light arcs, every vessel's lights and shapes, sound signals.

VIpp. 51-57

Buoyage, Lights and Pilotage

IALA A lateral and cardinal marks, isolated danger and safe water marks, light characteristics, sectored and leading lights, clearing bearings, entering harbour at night.

VIIpp. 58-63

Weather and Passage Planning

Shipping Forecast terms, depressions and fronts, sea breezes and fog, wind against tide and tidal gates, passage planning, night watches and fatigue.

VIIIpp. 64-69

Safety and Seamanship

The safety brief, man overboard, VHF and DSC distress calls, liferaft and EPIRB, fire, flooding, helicopter rescue, engine checks and anchoring.

IXpp. 70-73

Exam Revision

The chartwork order and the tides order on one page each, a night lights self-test and an exam-paper checklist.

At the end of the book: A revision section with the chartwork and tides order on one page each, a night lights self-test and an exam-paper checklist.

SHOW ME WHAT'S INSIDE

Plus: 2 Free Books

Exam-Style Practice Paper: Chartwork, Tides & Rules

BONUS 1: «Exam-Style Practice Paper: Chartwork, Tides & Rules»

Value on its own: US$ 17.90

Exam-style questions with full worked answers, so you can practise course to steer, secondary ports and collision situations before the real paper.

The 15 Most Common Skipper Theory Mistakes

BONUS 2: «The 15 Most Common Skipper Theory Mistakes»

Value on its own: US$ 14.90

The 15 most frequent slips in chartwork, tides and lights, each shown wrong and then right, so you spot them before the examiner does.

Offshore Skipper Theory Illustrated with 2 Free Books

  • Offshore Skipper Theory Illustrated: 73 illustrated pagesUS$ 63
  • BONUS 1: Exam-Style Practice Paper: Chartwork, Tides & RulesUS$ 17.90
  • BONUS 2: The 15 Most Common Skipper Theory MistakesUS$ 14.90
  • High-resolution PDF to printIncluded
Total value US$ 95.80
YOUR PRICE:
US$ 27
You save US$ 68.80
YES, I WANT OFFSHORE SKIPPER THEORY ILLUSTRATED FOR US$ 27

📄 This is a digital PDF book sent to your email: nothing is printed or shipped.

Secure purchaseEncrypted payment30-day guarantee

PDF by email: We email you Offshore Skipper Theory Illustrated as a PDF, together with the two free books. It's a single payment: no installments, no extra charges.

Who This Book Is For

You're on the theory course this winter

You're on the theory course this winter

Each evening's topic has its own page to read before or after class: the drawing first, then the steps in the order the instructor will use them.

Your exam paper is a few weeks away

Your exam paper is a few weeks away

The revision part puts the chartwork order and the tides order on one page each, so you rework fixes, course to steer and secondary ports without hesitating.

You already skipper your own boat

You already skipper your own boat

Sail or power, print it and keep it at the chart table: lights, marks, forecast terms and the safety brief, ready to check at a glance on passage.

Everything You Get Today

US$ 95.80US$ 27
YES, I WANT OFFSHORE SKIPPER THEORY ILLUSTRATED FOR US$ 27

📄 This is a digital PDF book sent to your email: nothing is printed or shipped.

30DAYS
GUARANTEE

30-Day Guarantee

Try Offshore Skipper Theory Illustrated for 30 days, bonus books included.

We refund everything if the file won't open, if the book isn't what you see here, if you were charged twice or if the email doesn't arrive. Just email us.

You pay once. No subscriptions.

Frequently Asked Questions

Is it for me if I did my Day Skipper years ago and I'm starting Coastal Skipper / Yachtmaster theory now?

Yes. Part I runs quickly through the chart basics, then every page builds to the level of the theory syllabus: running fixes, course to steer over several hours, secondary ports, the full collision rules.

Where does the content come from?

From the published Coastal Skipper / Yachtmaster Offshore shorebased theory syllabus, the IRPCS as applied in the UK by MCA MSN 1781, the IALA Region A buoyage system, UKHO chart symbols (Chart 5011) and Met Office Shipping Forecast terminology. UK conventions throughout: nautical miles, degrees true and magnetic, heights in metres above chart datum, tidal curves for standard and secondary ports, including the Solent. Tidal data in the examples are practice data, not for navigation.

Is it official material?

No. It's an independent study guide, not affiliated with or endorsed by the RYA, the MCA or the UKHO. It doesn't give a certificate: your qualification comes from your recognised course and exam.

Does it replace the theory course?

No. Keep your course notes and your almanac: they give you the text and the tables. This gives you each calculation drawn on the chart, with the steps in the order you use them, one topic per page, to revise before class and keep at the chart table.

Are the practice questions the ones in the exam?

No. They're written for this book, in exam style, with full worked answers. They aren't official exam questions.

When and how does it arrive?

The book and the two gifts arrive as PDFs by email, to the address you enter at checkout.

Do I have to pay every month?

No. It's a one-off payment.

Can I have it on paper?

It's a PDF, not a printed book: it arrives by email and you print it yourself, at home or at a print shop. The layout uses short sentences and large type, made to sit on the chart table.

How does the refund work?

You have 30 days. We refund everything if the file won't open, if the book isn't what you see on this page, if you were charged twice or if the email doesn't arrive: just email us.

Before You Close This Page

No more rereading the notes with nothing sticking.

A secondary port height, drawn on the curve, and done.

You walk into the exam knowing where everything is.

Drawings make studying faster.

The book is right below.

One-time payment: US$ 27 · Guarantee: 30 days · PDF by email

YES, I WANT OFFSHORE SKIPPER THEORY ILLUSTRATED FOR US$ 27

📄 This is a digital PDF book sent to your email: nothing is printed or shipped.