How to fill out a sailing log book

Look, keeping a sailing log book isn't just some bureaucratic exercise. It's something every sailor should actually do, whether you're just messing around on weekends or crossing oceans. A decent log isn't a diary you write in when you're bored. It's a legal document, a safety net, and honestly, a pretty good way to track how your boat's performing. This'll walk you through what goes where, how not to screw it up, and what to avoid.

What are the essential columns in a sailing log book?

Standard logs have a bunch of columns. The big ones? Date, Time (use 24-hour format, it's just easier), and Log Number. You gotta put in where the boat is - latitude and longitude. Course, which is your compass heading. Speed in knots. Then there's wind direction and speed, barometric pressure, sea state, and engine hours. Don't forget the Remarks column. That's where you scribble down anything interesting - sail changes, stuff you fixed, or spotting another boat.

How do you log a day's sail correctly?

Start at the beginning of your trip, make entries every hour if you can, and definitely at the end. Write down the date and log number. Note the time you untied from the dock. Weather conditions and where you left from. Every hour, update your position, course, and speed. In that Remarks section, mention anything that changed - like reefing a sail, dodging a tanker, or turning the engine on. At the end, log when you tied up, where you ended up, and a quick summary of the day.

What should you write in the Remarks column?

This is the story of your day on the water. Things like "Set main and jib at 1400" or "Changed course because a squall was coming." Maybe "Took a GPS fix" or "Saw a buoy marking a wreck." If something bad happens - a man overboard drill, a collision - this becomes really important legally. Be precise. Use proper nautical terms. Don't get poetic, just state what happened.

How often should you update the log book?

Depends on what you're doing. Coastal cruising in nice weather? Every hour is fine. Heavy weather or tight spaces? Every 30 minutes, maybe even 15. Ocean passages work on watches - each watch officer makes entries at the top of every hour. The thing is consistency. A gap in your log looks bad if you ever need to make an insurance claim or deal with legal stuff.

Common mistakes to avoid

• Using pencil: Always use a pen - preferably waterproof. Pencil fades and smudges. Makes the whole thing useless.
• Erasing errors: Don't erase anything. Draw a single line through the mistake, write the correct info above it, and initial it. Shows you're not hiding anything.
• Omitting weather data: Always record wind, pressure, sea state. This stuff matters for routing and figuring out patterns later.
• Forgetting engine hours: Even if you're sailing most of the time, note when the engine starts and stops. Crucial for maintenance.
• Leaving the log on deck: Keep it somewhere dry. A wet log is a useless log. End of story.

Data table: Standard log book format

Checklist for a proper log entry

• Date and time in UTC or local time (pick one and stick with it).
• Accurate position - GPS or celestial fix, doesn't matter.
• True or magnetic course (say which one).
• Speed over ground or through water (again, specify).
• Wind direction and speed - true or apparent, your call.
• Barometric pressure and whether it's rising, falling, or steady.
• Sea state - calm, moderate, rough, whatever fits.
• Engine hours - when it started, when it stopped.
• Significant events in the Remarks column.
• Signature or initials of whoever's on watch.

Frequently asked questions