Buoyage and Harbour Pilotage

Prerequisites

• You have worked through Charts and Position Fixing (chart symbols, bearings, True and Magnetic) and Tides and Course to Steer (heights of tide and streams).
• You know the basics of the collision regulations, especially the narrow channel and traffic separation rules, at the level of the lesson Passing the ICC Practical Assessment.
• You can handle your boat under engine in a harbour. Close-quarters handling is covered in the practical lessons such as Motor Cruiser Handling.

Learning Objectives

By the end of this lesson you will be able to:

• Identify every IALA mark (lateral, preferred channel, cardinal, isolated danger, safe water, special and new-danger marks) by shape, colour, topmark and light, and say what it means and what you do about it (test guidance, Pilotage 1).
• Explain the difference between IALA Region A and Region B, and know where each is used.
• Decode light characteristics on a chart, such as Fl(2)10s or Q(6)+LFl15s.
• Say where to find local regulations, port entry and departure signals, VTS and Port Operations radio information for a harbour (ICC coastal syllabus, Navigation 2; test guidance, Pilotage 2).
• Plan a harbour entry or departure for a small boat, taking account of large vessels and hazards, using transits, clearing lines and leading lights (Navigation 3; test guidance, Pilotage 3).

What the Examiner Will Ask

The RYA guidance gives the examiner three pilotage points:

1. Questions about buoys "should be in the form of 'What is this buoy and what is its significance?'" So you will be shown a mark (on a chart, a card or a picture) and asked to name it and say what it means for you.
2. "Where would you find the local regulations for (a) harbour?" The examiner must make sure you know "that local rules exist and can be found in Sailing Directions / Pilot Books and Nautical Almanacs."
3. "Use a sample chart and talk through the main points in the entry or departure plan. In particular, make sure that the plan is appropriate to a small boat and not a large ship."

That last phrase matters: a small-boat plan uses the shallow water outside the big-ship channel and keeps out of the way of ships.

The IALA Buoyage System

Buoys and beacons worldwide follow the IALA Maritime Buoyage System. Identify a mark by its colour and topmark by day and its light colour and rhythm by night. Shape (can, cone, pillar, spar) helps but is less reliable, since many pillar and spar buoys carry lateral colours.

Region A and Region B

There is one difference between the two IALA regions, and it only affects the lateral marks:

• Region A: port-hand marks are red, starboard-hand marks are green. Used in Europe (including the whole Mediterranean), Africa, most of Asia, Australia and New Zealand.
• Region B: port-hand marks are green, starboard-hand marks are red ("red right returning"). Used in North, Central and South America, Japan, South Korea and the Philippines.

Shapes do not change: cans are always port-hand marks and cones are always starboard-hand marks. Cardinal, isolated danger, safe water and special marks are identical in both regions.

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Chartering anywhere in Europe, it is Region A. In parts of the Caribbean, such as the Virgin Islands and the Bahamas, it is Region B.

Lateral Marks

Lateral marks show the sides of a channel.

Direction of buoyage

"Port-hand" means the mark should be on your port side when you are going in the direction of buoyage. That direction is:

• Inbound: from seaward towards a harbour, river or estuary.
• Around coasts, a general direction set by the authorities, shown on charts by a magenta arrow with two blobs. Around the UK it runs broadly from south-west to north-east: up the English Channel, up the west coast and up the east coast towards the north.

So leaving harbour, you leave the red marks to starboard and the green marks to port.

What do you do? Inbound in Region A, keep the red can on your port side and the green cone on your starboard side. Stay inside the channel they mark, and for a small boat, near its starboard edge (see the section on large vessels).

Preferred channel marks

Where a channel divides, a modified lateral mark shows which branch is the main one:

• Preferred channel to starboard: a port-hand mark (red can) with a broad green band, red can topmark, light Fl(2+1)R. Treat it as a port-hand mark to stay in the main channel.
• Preferred channel to port: a starboard-hand mark (green cone) with a broad red band, green cone topmark, light Fl(2+1)G. Treat it as a starboard-hand mark to stay in the main channel.

Cardinal Marks

A cardinal mark tells you which side of a danger the safe water lies. A north cardinal is placed to the north of a danger, so you pass north of it. Cardinal marks are yellow and black pillars or spars with two black cone topmarks.

Memory aids:

• The cone points show where the black is: points up, black at the top (north); points down, black at the bottom (south); points out, black at both ends (east); points in, black in the middle (west).
• The lights follow a clock face: 3 flashes at 3 o'clock (east), 6 at 6 o'clock (south), 9 at 9 o'clock (west), continuous at 12 (north). The long flash after the south cardinal's six makes it hard to confuse with an east or west.

What do you do? Pass on the side named by the mark, at a sensible distance. "That is a south cardinal. The danger is to the north of it, so I pass to the south."

Other Marks

Isolated danger mark

• Black with one or more broad red bands, pillar or spar.
• Topmark: two black spheres, one above the other.
• Light: white, Fl(2) (group of two flashes).
• Meaning: it is placed on a small, isolated danger with navigable water all round. Pass on either side, but give it a wide berth: the mark is on top of the danger. Memory aid: two spheres, two flashes.

Safe water mark

• Red and white vertical stripes, spherical, pillar or spar.
• Topmark: a single red sphere.
• Light: white, Iso, Oc, LFl 10s or Morse "A" (Mo(A), dot-dash).
• Meaning: safe water all round. It often marks the landfall, the start of a buoyed channel or the centre line of a channel. It is a good waypoint when approaching a harbour from seaward.

Special mark

• Yellow, any shape that does not conflict with other marks.
• Topmark: a single yellow X (St Andrew's cross).
• Light: yellow, any rhythm not used for white lights.
• Meaning: not mainly a navigation mark. It marks a special area or feature: a racing mark, a spoil ground, a military exercise area, a pipeline or cable, a data buoy, a water-ski or swimming zone. Look at the chart and pilot book to find out what. In the Mediterranean, lines of small yellow buoys parallel to the beach mark swimming zones (often about 200 to 300 m from the shore) where motor boats are prohibited or restricted to slow speed in a marked access lane.

New dangers and the emergency wreck marking buoy

A new danger is one not yet shown on charts or in sailing directions, such as a recent wreck. Authorities mark it quickly with normal cardinal or lateral marks, often duplicated (two identical marks), and sometimes with a radar beacon (racon) showing the Morse letter "D".

Many authorities, including Trinity House in the UK, also use the emergency wreck marking buoy:

• Blue and yellow vertical stripes.
• Topmark: an upright yellow cross (+).
• Light: alternating blue and yellow flashes.

What do you do? Treat it as a serious danger that is not on your chart. Keep well clear and check Notices to Mariners and navigational warnings (Navtex and VHF) for details.

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Light Characteristics

Most marks and all lighthouses carry lights, and each light has a characteristic so you can identify it at night. The chart gives it in a short form beside the light's flare symbol.

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Decoding a full characteristic

A chart beside a lighthouse reads Fl(2)WR 10s 15m 12/9M:

• Fl(2): groups of two flashes.
• WR: white and red, which on a lighthouse means sectors. You see red in the danger sector and white in the safe sector.
• 10s: the full cycle (period) repeats every 10 seconds.
• 15m: the light is 15 metres above MHWS.
• 12/9M: nominal range 12 miles for white, 9 miles for red.

To identify a light, count the flashes in a group and time the period from the first flash of one group to the first flash of the next.

Answering the examiner

Use the formula: name, meaning, action. For example:

• "That is a west cardinal: yellow, black, yellow, cones point to point, Q(9) every 15 seconds at night. The danger is to the east, so I pass to the west."
• "That is a red can with a red can topmark: a port-hand lateral mark in Region A. Going into harbour I keep it on my port side."
• "That is an isolated danger mark: black with a red band and two black balls. There is a small danger right under it with safe water all round, so I give it a wide berth on either side."

Local Regulations and Where to Find Them

Harbours add their own rules to the collision regulations, for example:

• Speed limits (often 4 to 6 knots in harbours and marinas, and 3 to 5 knots near beaches in many Mediterranean countries).
• Small-craft channels, or a requirement for small craft to keep outside the main channel.
• Areas where anchoring, fishing or swimming is prohibited.
• Rules around large vessels, such as Southampton's moving prohibited zone extending 1,000 metres ahead of a large vessel and 100 metres either side of it.

Where to find them:

• Pilot books (sailing directions): yachting pilots from Imray, Bloomsbury (Adlard Coles) and others, and Admiralty Sailing Directions. They describe the approach, hazards, regulations, berthing and facilities for each harbour.
• Nautical almanacs, such as Reeds: a page per harbour with the VHF channels, signals, local rules, tidal data and a harbour plan.
• Harbour authority websites, local Notices to Mariners and the harbour master's office.
• Chart notes, the charter briefing and, abroad, the harbour master's office (the port police in Greece).

Answer the examiner simply: "Local rules for that harbour are in the pilot book and the almanac, and on the harbour authority's website. I would also listen to the port's VHF channel as I approach."

Port Signals, VTS and Port Operations Radio

International Port Traffic Signals

Many larger ports control traffic with lights shown from a signal mast at the entrance. Most use the International Port Traffic Signals (IPTS): three lights in a vertical line.

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A yellow light to the left of the top main light, shown with signal 2 or 5, means vessels that can navigate safely outside the main channel need not comply. Small craft often fall into this group, but check the local rules: many ports define exactly which vessels qualify.

Some ports use older local signals; the almanac lists what each port uses. If in doubt, stay out and call the port on VHF.

VTS and Port Operations radio

• Vessel Traffic Services (VTS) manage shipping in busy ports with radar and AIS. Large vessels must report; small craft usually need not, but should listen and keep clear.
• Port Operations (or harbour radio) is the port's working VHF channel for traffic information, berthing and permissions. Marinas have their own channel, often 80 in the UK.
• Channel numbers are in the almanac, the pilot book, on the chart (a small magenta circle with the channel) and on the port's website.

Good practice for a small boat:

1. Before entering or leaving, look up the port's VHF channel and any reporting points.
2. Listen on that channel as you approach (dual-watch with channel 16 if your radio allows). You will hear when ships are moving and whether the port wants small craft to wait.
3. Call only if the local rules require it, if you need instructions, or if you need to cross a channel and are unsure.
4. Do not use channel 16 for routine port traffic.

Planning a Harbour Entry or Departure

Pilotage is navigation by eye in confined waters, with no time for chartwork, so you do the thinking beforehand.

What a small-boat pilotage plan contains

1. Timing. Height of tide for enough depth (add the height of tide to the charted depths, or subtract drying heights), the tidal stream in the entrance (avoid a strong stream against a strong wind), and daylight.
2. The approach. A safe starting point (often a safe water mark or a clearly identifiable headland) and the first mark to find.
3. The route in legs. Each leg from mark to mark, with its bearing (magnetic) and distance, and what you should see at the end of it.
4. Hazards along each leg: rocks, shallows, wrecks, moorings, and the depth you should see on the echo sounder.
5. Safety lines. Transits, leading lines, clearing bearings or depth contours that keep you clear of the hazards.
6. Traffic. Where the big-ship channel is and where you will be in relation to it; ferries and their berths; places where you must cross.
7. Local rules and signals: speed limits, port traffic signals, VHF channels.
8. The berth. Where you are going, which side to, fenders and lines needed.
9. Abort points and a plan B. Where you turn back if the marks are not where they should be, or the entrance looks too rough, and where you go instead.

Write it large on one card that can be read on deck, ideally with a sketch of the entrance.

Transits and leading lines

A transit is two charted objects seen in line. While they stay in line, you are on the line drawn through them on the chart. A transit needs no compass, works in a cross-tide (you see drift immediately as the objects open) and is very accurate. Natural transits (a rock on a hilltop, a church in line with a headland) and man-made ones (two beacons) both work.

A leading line is a transit laid out on purpose: two marks or lights, the rear one higher, set up so that keeping them in line takes you down the safe channel. If the rear mark appears to the left of the front, you are to the left of the line: steer right until they line up again.

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Clearing bearings

A clearing bearing (clearing line) is a bearing on a charted object that keeps you clear of a danger. You draw a line from the object past the edge of the danger, measure it, and note whether you must keep the bearing more or less than that value.

For example, a shoal lies south of your approach. A line from a church spire just north of the shoal measures 270°M. As long as the spire bears less than 270°M you are north of the line and clear. If it creeps above 270°, you are standing into danger: alter away at once. Write it as "Spire NMT 270°M" (not more than).

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Keeping clear of large vessels

This is where a small-boat plan differs from a ship's plan.

• Use the shallow water. A ship needs the dredged channel. You often do not. Plan to run along the edge of the channel or just outside it, in water deep enough for your draught at that state of tide. Many harbours have a recommended small-craft track for exactly this reason.
• Rule 9. In a narrow channel a vessel under 20 metres, or a sailing vessel, must not impede a vessel that can navigate safely only within the channel. Keep to the starboard side of the channel.
• Crossing. If you must cross a channel, do it at right angles (your heading, not your track), quickly, and when it is clear in both directions. Choose a crossing point with good visibility, not on a bend.
• Big ships cannot stop or turn. A large ship may need a mile or more to stop, and may not see you close under its bow.
• Listen on the port channel and watch AIS if you have it.
• Look astern for ships and fast ferries.

Departure plans

A departure plan is the same in reverse, prepared before you cast off: signals, the route out with its safety lines, traffic and the first position at sea.

At night

The same plan works at night using light characteristics, sector lights, leading lights and the echo sounder, but unlit buoys vanish. Avoid entering an unfamiliar harbour at night if you can.

Worked Example: A Small-Boat Entry Plan

The examiner shows a sample chart of a harbour with a buoyed big-ship channel running north into it. On the west side of the entrance there is a drying rocky ledge, marked on its channel side by an east cardinal. On the east side the water shoals gently to 3 metres outside the channel. A ferry terminal is just inside. Your boat draws 1.8 m, and the height of tide on arrival will be 2.5 m.

Talk the examiner through it:

1. "From the almanac: local rules say small craft keep outside the main channel where possible, the port uses International Port Traffic Signals, and Port Operations is on its own VHF channel. I'd listen on it from two miles out."
2. "I start at the safe water mark at the outer end of the channel. My first leg is 355°M, about 1.5 miles."
3. "I run up the east side of the channel, just outside the green starboard-hand buoys. The charted depth there is 3 metres, plus 2.5 metres of tide, so about 5.5 metres. That leaves plenty under my 1.8 metre keel and keeps me out of the ships' way."
4. "The danger is the drying ledge on the west side. I'm keeping well east of it. The east cardinal tells me to pass to the east of it, which is where I'll be anyway."
5. "My safety line: a clearing bearing on the church spire ahead, NMT 010°M, keeps me east of the ledge. If the spire bears more than 010°, I'm being set west towards it. And the echo sounder should not show less than 4 metres."
6. "Before the entrance I check the port signals. If I see three red, small craft may still be allowed to proceed outside the channel only if the yellow exemption light is shown; otherwise I wait outside, clear of the channel."
7. "I keep a lookout astern for the ferry, and if one is leaving I wait outside the channel and let it pass. If the marks don't look right, or there's a big sea in the entrance, I turn back to the safe water mark and go to the bolt-hole harbour five miles east."
8. "Once inside, speed limit 5 knots, fenders and lines ready on port side for the visitors' pontoon."

That is a plan that fits a small boat: shallow water used safely, ships given the channel, hazards cleared by simple visual checks.

Common Mistakes

• Describing a buoy instead of interpreting it. The examiner wants the name and what you do about it.
• Forgetting the direction of buoyage. Leaving harbour, the red marks go to starboard (in Region A).
• Cutting close to an isolated danger mark. It sits on top of the danger.
• Assuming Region A everywhere. Lateral colours are reversed in the Americas and parts of the Caribbean.
• Writing a ship's plan. Following the deep-water channel in a small boat puts you in the way of ships. Use the edges and the shallow water where depth allows.
• Not knowing where local rules are. Pilot book, almanac, harbour authority. Say so.
• No safety lines. A plan with legs but no transit, clearing bearing or depth check gives no warning if you drift.

Summary

• IALA marks are identified by colour, topmark and light; shape helps. Region A (Europe and most of the world) uses red to port; Region B (the Americas, Japan, Korea, Philippines) uses green to port. Shapes are the same in both.
• Lateral marks show the channel sides in the direction of buoyage (inbound from sea). Preferred channel marks have a band and an Fl(2+1) light.
• Cardinal marks show where the safe water is: pass on the named side. Lights follow the clock: continuous, 3, 6 plus long, 9.
• Isolated danger: black and red, two black balls, Fl(2). Safe water: red and white stripes, red ball, Iso/Oc/LFl 10s/Mo(A). Special: yellow, yellow X. Emergency wreck: blue and yellow stripes, yellow cross, alternating blue and yellow light.
• Local regulations are in pilot books, almanacs and harbour authority sources.
• IPTS: flashing red, emergency; three red, do not proceed; three green, one-way; green, green, white, two-way; green, white, green, only on specific orders. A yellow light can exempt boats able to keep outside the main channel.
• Listen on the port's VHF channel.
• A small-boat pilotage plan covers timing, legs, hazards, safety lines, traffic, rules, the berth and an abort plan, and keeps out of the big ships' way.

Check Your Understanding

1. You see a yellow and black pillar buoy, black at the top, with two cones both pointing up. What is it and what do you do?

Answer: A north cardinal mark. The safe water is to the north, so pass to the north of it. At night it shows a continuous quick or very quick white light.

1. At night you see a white light flashing in groups of two every 10 seconds, on a black buoy with a red band. What is it?

Answer: An isolated danger mark. It is on top of a small danger with safe water all round, so pass on either side at a good distance.

1. You are leaving a harbour in Region A. Which side do you keep the red can buoys?

Answer: On your starboard side. Red marks are to port only when going in the direction of buoyage, which is inbound from seaward.

1. You charter a yacht in the British Virgin Islands. What changes in the buoyage?

Answer: It is IALA Region B, so port-hand marks (cans) are green and starboard-hand marks (cones) are red. Inbound, keep the red marks to starboard. Cardinal and other marks are the same.

1. What is a yellow buoy with an X topmark, and what should you do?

Answer: A special mark. It marks a special area or feature (swimming zone, cable, spoil ground, exercise area, data buoy). Check the chart and pilot book for what it marks and any rules, such as a speed limit or no-go zone.

1. You see a blue and yellow striped buoy with a yellow cross on top. What does it mean?

Answer: An emergency wreck marking buoy: a new wreck not yet on the chart. Keep well clear and check navigational warnings and Notices to Mariners.

1. Where would you find the local regulations for a harbour you have never visited?

Answer: In the pilot book (sailing directions) and the nautical almanac for the area, backed up by the harbour authority's website, local Notices to Mariners, chart notes and the charter or marina briefing.

1. Approaching a port, you see three green lights in a vertical line on the signal mast. What does it mean?

Answer: International Port Traffic Signal 3: vessels may proceed, one-way traffic.

1. What does green, white, green in a vertical line mean?

Answer: Signal 5: a vessel may proceed only when it has received specific orders to do so, usually by VHF from the port or VTS.

1. Give three features that make an entry plan suitable for a small boat rather than a large ship.

Answer: Any three of: using water outside or at the edge of the main channel where depth allows; keeping to the starboard side of a narrow channel and not impeding ships (Rule 9); crossing the channel at right angles and only when clear; listening on the port's VHF channel; using transits, clearing bearings and depth checks; having an abort point and a bolt-hole; keeping a lookout astern for ships and ferries.