How to keep a sailing log

So you're thinking about keeping a sailing log. Honestly, it's not just some fancy diary you keep to look like a real sailor. It's your boat's memory, a legal safety net, and honestly, a tool that'll save your butt someday. Whether you're crossing an ocean or just messing around near the coast, writing stuff down consistently makes everything safer, helps you keep track of repairs, and gives you something useful to look back on for your next trip. Here's the real deal on what to jot down and how to organize it so it actually works.

What are the essential elements of a sailing log entry?

Every single entry should capture a quick snapshot of what's happening right then. Time, where you are, which way you're pointing — those are the big ones. But if you want to do this right you gotta go deeper. Always write the date and time in UTC (Zulu time, whatever you wanna call it) so you don't get tangled up crossing time zones. Position, latitude and longitude, compass course, speed in knots. Wind direction and speed, sea state, barometer reading, visibility. And don't forget engine hours if it's running, plus anything weird that happened — sail changes, spotting a buoy, crew swapping shifts.

How do you structure a paper sailing logbook?

Old school paper logs use columns. Left page is all the numbers, right page is where the story goes. The navigation side should have slots for Time, Course, Speed, Log distance, Wind, Barometer, and Position. The remarks side? That's where you get to free-form. A trick I picked up: draw a horizontal line across the page after every watch or every hour. Keeps things clean and makes it harder to skip something important. That way you can glance back and find what you need fast.

What is the difference between a deck log and an engine log?

Most boats actually keep two separate books. The deck log (navigation log) is all about sailing and weather stuff. The engine log is strictly mechanical — start times, stop times, RPM, oil pressure, coolant temp, fuel burn. You keep 'em separate because the engine log is for maintenance schedules and warranty claims, while the deck log is for navigation and covering your legal ass. If you only have one logbook, at least separate the sections with a tab or a big obvious header.

How often should you make a log entry?

Depends on what you're doing. Coastal cruising or busy waters? Every 30 minutes, or every time you change course. Ocean crossing? Hourly is standard. Racing? Try every 15 minutes or every time you tweak a sail. The golden rule: log whenever the boat changes course, speed, or sail setup. I like to log at the top of every hour, then note anything major that happens in between.

What should you record in the remarks section?

This is where the human story lives. Sail changes ("Reefed main at 1400"), navigation marks ("Passed Buoy R2 at 1545"), crew changes, radio calls, meals, anything weird. This part is super important for incidents too. Near-collision? Gear failure? Medical issue? Write it down factual and detailed. These notes can hold up in court or for insurance claims. Trust me on this one.

Checklist for a Complete Log Entry

• Date and Time (UTC)
• Vessel Position (Lat/Lon or bearing from a mark)
• Course Steered (Magnetic or True)
• Speed Over Ground (SOG) or Speed Through Water
• Wind Direction and Speed (True or Apparent)
• State and Swell Height
• Barometric Pressure and Trend
• Visibility (in nautical miles)
• Engine RPM and Hours (if running)
• Significant Events (sail changes, hazards, crew changes)

Frequently Asked Questions

Expert Insights on Logging Best Practices

Pros talk about "logging by exception." Means you stick to a standard pattern — hourly entries — and only write down stuff that breaks the pattern. Like if the wind is steady at 20 knots from the west, you don't need to say "wind steady" every hour. Just log when it shifts. Keeps things concise. Another thing: always log the barometer trend (rising, falling, steady) not just the number. A falling barometer is a bigger warning than the actual pressure reading.

"The logbook is the memory of the vessel. When you are tired, stressed, or in a crisis, you cannot rely on your own memory. You rely on the log. A good log is the difference between a safe passage and a confused one." — Captain John R. Smith, Ocean Navigator

Common Logging Mistakes to Avoid

• Using pencil: Fades and can be erased. Use a waterproof pen.
• Forgetting to log engine hours: Critical for maintenance schedules.
• Logging only position: Without time and course, it's useless for reconstructing the voyage.
• Not logging weather changes: Sudden shifts in wind or pressure are vital for forecasting.
• Using local time: Always use UTC to avoid confusion when crossing time zones.