# Sailing Quick Reference

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## Points of Sail

The point of sail describes the angle between the boat's heading and the true wind direction.

| Point of Sail | True Wind Angle | Description |
|---|---|---|
| In irons | 0–30° | Head-to-wind, sails luffing, no drive |
| Close hauled | ~30–45° | Sailing as close to the wind as possible |
| Close reach | ~45–60° | Between close hauled and beam reach |
| Beam reach | ~90° | Wind directly abeam — often fastest point |
| Broad reach | ~120–150° | Wind on the quarter — comfortable, fast |
| Run | ~150–180° | Wind from directly behind |

**No-go zone:** ~0–30° on either side of the wind — the boat cannot make progress sailing directly into the wind.

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## Tacking vs. Gybing

**Tacking** — turning the bow through the wind (bow crosses the wind). The boom swings across from one side to the other. Used to head upwind.

**Gybing** — turning the stern through the wind (stern crosses the wind). The boom can swing violently — always control the mainsheet. Used to change direction downwind.

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## Sail Trim Basics

**Telltales** — strips of yarn or fabric on the sail.
- Both telltales streaming aft → sail trimmed correctly
- Windward telltale lifting → sheet in (trim), or bear away
- Leeward telltale lifting → sheet out (ease), or head up

**In irons fix:** Let sails luff, push boom to one side, fall off onto a tack.

**Reef** — reducing sail area by partially lowering the mainsail and tying off the excess. Reef before you think you need to. Typical thresholds: first reef ~15–18 kt, second reef ~21–25 kt.

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## Hull Speed

The theoretical maximum displacement hull speed:

**Hull speed (kt) ≈ 1.34 × √(waterline length in feet)**

| LOA | Hull Speed |
|---|---|
| 20 ft | ~6.0 kt |
| 23 ft | ~6.4 kt |
| 30 ft | ~7.3 kt |
| 40 ft | ~8.5 kt |

A modern fin-keel boat can exceed hull speed in planing conditions (surfing downwind in big waves).

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## Navigation Lights — Quick Reference

| Situation | What You See | What It Is |
|---|---|---|
| Red + green + white | Two side lights + stern | Head-on approach |
| Red only | Port sidelight | Vessel crossing left-to-right in front of you |
| Green only | Starboard sidelight | Vessel crossing right-to-left — you are give-way |
| White only (masthead) + green | Overtaking from starboard | Vessel overtaking you on starboard |
| Two white (stacked) + red/green | Two masthead lights | Large ship (≥50 m) underway under power |
| Red + white (all-round, vertical) | Not under command | Give way — vessel cannot maneuver |
| Green + white (all-round, vertical) | Trawler | Give way — engaged in fishing |
| White all-round only | At anchor | Avoid — vessel at anchor |
| White + red all-round (vertical) | Pilot vessel | Pilot boat on duty |

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## Day Shapes

| Shape | Meaning |
|---|---|
| ⚫ Black ball | Vessel at anchor |
| 🔻 Black cone (apex down) | Sailing vessel motorsailing |
| ⚫ ⚫ Two balls (vertical) | Not under command |
| ⚫ ◆ ⚫ Ball-diamond-ball | Restricted in ability to maneuver |
| ▬ Black cylinder | Constrained by draft |

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## Beaufort Wind Scale

| Force | kt | Description | Sea State |
|---|---|---|---|
| 0 | < 1 | Calm | Mirror smooth |
| 1 | 1–3 | Light air | Ripples |
| 2 | 4–6 | Light breeze | Small wavelets |
| 3 | 7–10 | Gentle breeze | Scattered whitecaps |
| 4 | 11–16 | Moderate breeze | Moderate waves, frequent whitecaps |
| 5 | 17–21 | Fresh breeze | Long waves, many whitecaps, spray |
| 6 | 22–27 | Strong breeze | Large waves, spray, whitecaps everywhere |
| 7 | 28–33 | Near gale | Sea heaping up, foam streaks |
| 8 | 34–40 | Gale | Moderately high waves, edges blowing |
| 9 | 41–47 | Strong gale | High waves, dense foam, visibility affected |
| 10 | 48–55 | Storm | Very high waves, sea white, heavy sea roll |
| 11 | 56–63 | Violent storm | Exceptionally high waves |
| 12 | 64+ | Hurricane force | Air filled with foam, visibility nil |

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## Common Knots

**Bowline** — fixed loop that won't slip. The classic sailing knot. "The rabbit comes out of the hole, round the tree, and back down the hole."

**Cleat hitch** — securing a line to a cleat. Take a round turn around the base, then two figure-8 turns, then one locking hitch over the horn.

**Clove hitch** — temporary attachment to a post or rail. Two half hitches; easy to adjust and release.

**Figure-eight** — stopper knot. Prevents a line from running through a block or fairlead.

**Round turn and two half hitches** — secure, adjustable attachment to a ring or rail.

**Reef knot** — joining two lines of similar diameter. Right over left, left over right. Not for critical loads — use a sheet bend for mismatched diameters.

**Sheet bend** — joining two lines of different diameter. The thicker line forms the loop.

**Rolling hitch** — attaching to another line or spar under load. Grips when pulled along the spar.

**Anchor hitch (fisherman's bend)** — the correct knot for attaching a line to an anchor.

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## Buoyage — IALA System B (Americas, Japan, Philippines, Korea)

**Red right returning** — red buoys on the starboard side when returning from sea.

| Mark | Shape | Color | Top Mark | Meaning |
|---|---|---|---|---|
| Port lateral | Can / pillar | Red | None | Keep to starboard (IALA-B: keep red to starboard) |
| Starboard lateral | Nun / cone | Green | Cone | Keep to port |
| Safe water | Sphere | Red + white vertical stripes | Sphere | Safe water on all sides |
| Isolated danger | Pillar / spar | Black + red bands | Two black balls | Isolated danger, safe water around it |
| Special mark | Any | Yellow | Yellow X | Special purpose (mooring, racing, TSS) |
| Cardinal (N) | Pillar / spar | Black over yellow | Two cones pointing up | Pass to the north |
| Cardinal (S) | Pillar / spar | Yellow over black | Two cones pointing down | Pass to the south |
| Cardinal (E) | Pillar / spar | Black-yellow-black bands | Cones base-to-base | Pass to the east |
| Cardinal (W) | Pillar / spar | Yellow-black-yellow bands | Cones point-to-point | Pass to the west |

*IALA-A (Europe, Africa, most of Asia):* Red/green assignments are reversed — "red left returning."

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## VHF Radio Channels

| Channel | Use |
|---|---|
| 16 | **International distress, safety, and calling** — always monitor |
| 22A | US Coast Guard working channel |
| 9 | Boater calling channel (US) |
| 6 | Ship-to-ship safety communications |
| 13 | Bridge-to-bridge (1 watt) |
| 70 | DSC digital selective calling — do not use for voice |
| 24, 25, 26, 27, 28 | Public correspondence (marine operator) |

**MAYDAY procedure:**
1. MAYDAY MAYDAY MAYDAY
2. This is [vessel name × 3]
3. MAYDAY [vessel name]
4. Position
5. Nature of distress
6. Number of persons aboard
7. Any other information
8. Over

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## Tide and Current Basics

**Flood** — tide coming in (rising sea level).
**Ebb** — tide going out (falling sea level).
**Slack** — the period of minimal current around high and low water.

Rule of twelfths — tide rises/falls unevenly:
- Hour 1: 1/12 of range
- Hour 2: 2/12 of range
- Hour 3: 3/12 of range ← fastest
- Hour 4: 3/12 of range ← fastest
- Hour 5: 2/12 of range
- Hour 6: 1/12 of range

**Spring tides** — larger range; occur near new and full moon.
**Neap tides** — smaller range; occur near quarter moons.

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## Distress Signals (Rule 37 / SOLAS)

Any of these signals indicate distress and request assistance:
- Red parachute flare or red hand flare
- Orange smoke signal
- MAYDAY spoken over radio (Ch 16)
- SOS (···−−−···) by any signaling method
- Continuous foghorn sound
- Gun fired at approximately 1-minute intervals
- Flames on the vessel
- Slowly and repeatedly raising and lowering both arms
- Square flag with ball above or below it
- Orange dye in water
- Satellite EPIRB signal