An Illustrated Guide to Maritime Signal Flags

(rabbitwaves.ca)

117 points | by gaws 5 days ago ago

23 comments

  • function_seven 11 hours ago

    So I just read the other thread about the K language[1] and how it's so-very-concise syntax made the author feel certain ways.

    But that has nothing on this! From page 70 of the International Code of Signals[2], we find that PG 2 means, "I am dazzled by your searchlight. Extinguish it or lift it."

    Not bad, but what if you reply with "AX 1"? Lots going on there! "Shall I train my searchlight nearly vertical on a cloud, intermittently if possible, and, if your aircraft is seen, deflect the beam upwind and on the water to facilitate your landing?"

    [1] https://news.ycombinator.com/item?id=41886051

    [2] https://rabbitwaves.ca/media/docs/ics_pub102bk.pdf

  • GJim 11 hours ago

    I have a copy of the International Maritime Organisation (IMO) Code of Signals on my bookshelf.

    3 letter medical flag codes include:

    MKH Foreskin will not go back to normal position

    MKI Patient has swelling of the testicles

    MLF Patient has Delirium Tremens

    It's a comprehensive book to say the least!

    • greggsy 11 hours ago

      I wonder how many times MLF has been used for a ship’s captain?

  • raldi 2 hours ago

    I liked the Flag Semaphore page it linked to, but it raises the question: Why are the letters almost, but not quite in clockwise order?

    If you sort by clock position, you get:

    A B C D E F G H I K L M N O P Q R S T U Y Cancel # J V W X Z

    Was it invented by someone whose alphabet didn't have J, V, W, X, Z?

  • roywiggins 3 hours ago

    Vaguely related: "Wuthering Heights in Semaphore" https://m.youtube.com/watch?v=kqiUGjghlzU

  • acidburnNSA 11 hours ago

    Fun fact based on the bottom panel: the peace sign (inverted y) is based on the flag semaphore signs for N and D, originally standing for Nuclear Disarmament.

    • raldi 2 hours ago

      This sounds like one of those ridiculous "facts" that gets passed around by word-of-mouth despite seeming suspiciously just-so.... and yet in this case, it appears to totally check out.

  • wrycoder 12 hours ago

    This is from 100 Rabbits. Great job!!

    One of my favorite flag signals is, “Nothing can be done until high tide.”

    • ahazred8ta 10 hours ago

      US1 Nothing can be done until daylight. US2 Nothing can be done until tide has risen. US3 Nothing can be done until visibility improves. US4 Nothing can be done until weather moderates. US5 Nothing can be done until draft is lightened. US6 Nothing can be done until tugs have arrived.

  • UniverseHacker 9 hours ago

    This seems like a great system, but in many years of sailing I've never encountered it actually used. For the most part is only possible to be used by large commercial vessels, but those vessels already have a dozen other redundant communication systems that are clearer and faster. Operators of small private vessels aren't likely to even know this system exists, not alone carry all of these flags, a code book, and a system for hoisting flags.

    • somat 3 hours ago

      I have only seen it on US navy vessels, I have never seen it used for communications, but they like to put up the ships id on the flags, And I always enjoy breaking out the manual and fumble my way through deciphering the flags when I see them.

    • tialaramex 7 hours ago

      Yes. Anything serious is internationally required to carry (and many smaller things would be required by local laws, or strongly advised to carry anyway) a modern digital maritime radio - the technology is called DSC, Digital Selective Calling.

      • UniverseHacker 6 hours ago

        Yes- and even many cheap handheld VHFs have DSC nowadays.

  • NKosmatos 8 hours ago

    Nice cartoonishly font, clear language, nice graphics and fast to load… why can’t more pages be like this one?

  • cbsks 11 hours ago

    Interesting that “Oscar” is pronounced “OSS CAH” and not “OSS CAR”. Same with Victor. Must have been made in New England (northeastern US).

    • tialaramex 8 hours ago

      These pronounciations are for the International radiotelephonic spelling alphabet, often referred to as a "NATO Phonetic alphabet". For numerals procedures vary slightly, and they've chosen IMO. The sounds are chosen to try to maximize the chance that two people who know this system, even if they don't speak any shared languages, will successfully communicate the symbols intended, so they're not about how you might pronounce these words in any particular place, but rather a plausible pronunciation everybody can approximate and understand.

    • raldi 2 hours ago

      I thought 5 was supposed to be pronounced "fife" but this page only seems to half say that. ("faif" in the first row, but "five" in the second)

    • brickers 11 hours ago

      Or… England?

      • cbsks 10 hours ago

        Ouch. My stereotypically-American US-centric bias is showing :)

      • pc86 11 hours ago

        Old England.

  • nnf 13 hours ago

    This is a neat style, and I was pleased to see that the author included accessible text since the visible text on the page is all in images.

  • foo42 12 hours ago

    I never knew anything about this. I love discovering this sort of thing!