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Crack the code of NATO’s flag signals

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Signal flags are more than just colourful banners. They are still important for Allied ships to communicate vital information as they sail in open seas. Watch this video to learn more about the fascinating world of signal flags.


Signal flags are colourful and eye-catching, but do you know what they mean? These flags are not just for decoration; they are still a vital way of sending messages across the seas. Each flag represents either letters or numbers that can be used together to form words or codes, or has a specific standalone meaning. By combining them in different ways, ships can communicate with each other, and with their surroundings in a snap.
Signal flags have a long and rich history that dates back to the 18th century when they were first used by naval and merchant vessels. Today, they are still used by NATO navies, especially in situations where radio communication is not possible, reliable or secure. Signal flags are not only a practical tool, but also a symbol of maritime culture and tradition.
Watch the Chief Yeoman on board the German Navy frigate FGS Bayern explain how Allies still use signal flags to communicate with each other.


Chief Petty Officer Alexander, Chief Yeoman, FGS Bayern, German Navy

Hi, my name is Chief Petty Officer Alexander. I'm Chief Yeoman on the German Navy ship FGS Bayern. And today I'm going to show you some signal flags which are cool. Follow me.

This one would be ‘Emergency Charlie’. This one is the ‘Emergency’ flag. There are 26 different kinds of possibilities. This one has a combination with the one I want to show you. ‘Charlie’, which means ‘collision danger’. And if you see that one with binoculars, you're fine. You still have time. But if you see that without binoculars, you're probably way too late. You're heading for collision.

The next signal I’m gonna show you has the meaning ‘movements are not understood’. In plain English, what's the matter with you? So this is flag ‘November’.

Communicating with flags is still important within NATO Allies. It's the only way to communicate without using radio frequencies.

For the next signal, if there was a CBRN attack in the area you're sailing in and you want to inform other people to not eat fresh fish out of this area. That's how you do it.

I'm combining ‘November Bravo’, which indicates it's from the nuclear, biological and chemical chapter, and the NATO numbers three tack one. ‘Tack’ means there's a little space in between them, so there are different kinds of combinations in that signal to tell different kinds of things, which could happen in the area you are sailing in. So this is ‘November’, this is flag ‘Bravo’, flag ‘Three’, the little space in between and flag ‘One’.

I like to be a yeoman. It's fun to do and there are so many different ways to communicate with flags.

And the next flag I'm going to show you is my favourite flag. It's flag ‘Prep’. You hoist it if you disengage from replenishment at sea with an auxiliary ship. It's actually kind of sad because you say farewell to your comrades at sea, but it's actually also a party on the upper deck with nice music.
Haterz [Instrumental] by Nathalie Mac and Henry Parsley
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