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Nautical Know How
  • Our Courses

      All our courses are engaging, interactive and fun! Whether formal training or simply looking to brush up, we take online learning to the next level.

    • Sailing EssentialsFreeA free course great for anyone who spends time on the water.
    • Essential Navigation & SeamanshipA great introduction to navigation and basic seamanship.
    • Day Skipper TheoryMany of the best skippers started their journey here.
    • Coastal Skipper / Yachtmaster® TheoryComing SoonEssential preparation for the Yachtmaster® practical exam.
    • SRC (VHF) Marine Radio CourseAn essential course for anyone intending to use a marine radio.
  • Directory

      Are you looking for something nautical related? Our directory is an extensive list of courses and places associated with the marine industry. Hop over and search now.

    • Places
      Find anywhere nauctical, including marinas u0026 training centres. If it exists, we’ve got it listed!
    • Courses
      We help you navigate through the complex world of training and help find what’s best for you.
  • Know-How

      We believe every day’s a school day on a boat! That’s why we built Nautical Know-How, dedicated to answering your questions. Even better, if it can’t answer your question immediately, you can request it, and we’ll add it to our knowledge base.

    • Nautical Terms & Terminology
      Understanding the language of the marine world is like trying to learn a pirate’s secret code while juggling fish. Let us explain why a sheet isn’t for your bed, why “heave ho” doesn’t mean throw up (most of the time), and why “dead reckoning” is surprisingly less ominous than it sounds.
    • Why do we have tides?
      Have you ever wondered what causes the tides? Check out this video, which introduces the forces that create the tides we experience on Earth.
    • What causes our weather?
      A video introducing the drivers behind our weather, part of our RYA Day Skipper u0026 RYA Coastal Skipper / Yachtmaster® Offshore theory courses.
    • Buoyage Flashcards
      Flashcards designed to help remember the buoys in the IALA system. If you want to learn them in detail, our module ‘Getting in and out of harbour‘, covers the IALA system and different buoys used.
    • Interactive Rule Book (COLREGs / IRPCS)
      Whether you’re a novice sailor or a seasoned skipper, we can help you navigate the IRPCS confidently and clearly. Our easy-to-use, easy-to-understand, plain English rule book with helpful interpretations of what each rule means.
    • The Salty Sea Blog
      From salty old sea dogs to fresh-faced deckhands, this blog is for anyone who finds peace, adventure, and a bit of mischief on the water. So hoist the main, set your course, and let’s sail into the stories, lessons, and musings that make life on the sea so irresistible.
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Published:26th October 202424th December 2024 Last Updated:24th December 2024
Flag Semaphore | Signals & Communication

Letter D (Flag Semaphore)

Letter D (Flag Semaphore)

This shape represents the Letter D (Flag Semaphore) and the Number 4 (Flag Semaphore).

Related Content:
  • Number 4 (Flag Semaphore)
  • Signalling & Communication

Message Translator







Icon

Semaphore Flag Signals

Unlock the timeless art of visual communication with our Semaphore Signals Guide! This must-have download breaks down the semaphore alphabet with clear illustrations of each arm position and corresponding...More Details
Free Download, Sailing Essentials
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