Dear readers,

If you have AIS on board, you will probably love it. Being able to see information such as the position, course and speed of other ships in the vicinity on the plotter is often worth its weight in gold when you're underway.

The technology is a blessing, especially when sailing in busy areas, for example in the triangle between Helgoland, Cuxhaven and the Weser on the North Sea. This is where busy commercial shipping lanes meet and dozens of big ships lie in the roadstead. Being able to follow their journey on the motorway of the ocean liners is great. Functions such as CPA and TCPA allow you to adjust your own course and speed with foresight.

That alone would provide safety, but investing a few hundred euros more in a device that also transmits pays off at sea. Sailors repeatedly report how the crew of a freighter changed course minimally long before a very close passage could occur, so that everything remains relaxed for both sides.

The flip side of the coin of active AIS: everyone else is also live. Online services such as Marinetraffic or Vesselfinder transmit the data of the transmitting ships on the Internet almost in real time. Anyone who knows which boat name they are looking for will find it. They can see where a club mate, friend, famous boat or fleeting sailing acquaintance is currently sailing.

Quite a few (long-distance) sailors manage a AIS transponder are now available for this purpose: So that friends and family at home can travel along virtually and know where the crew is.

But an encounter during a cruise in the Swedish archipelago last year showed me that it's not just people you know who follow you: in the evening at anchor, a man paddled up to our boat in a small sailing dinghy, quickly climbed on board and introduced himself by saying that he had been watching us for a few days. He asked us what the water depth was like in the small harbour we had been in the day before.

We had a chat and he left. But the realisation remained that we were making ourselves transparent and that complete strangers were obviously interested in our route. Now it's debatable whether you have to sail through the archipelago with an active AIS or whether it's better to use it on shipping lanes. But then also consistently. On the way back from this trip, we spotted a sailor a few miles ahead of us in the southern Baltic Sea who only ever transmitted when a large vessel appeared on his course. This on and off was rather irritating for other road users.

Of course, marine traffic and the like can also be very useful sources of information for trip planning: You can discover anchorages or guess what the conditions might be like by interpreting the course and speed of boats at sea.

However, I wonder when all those who have purchased an active AIS allowed (commercial) online services such as Marinetraffic to transmit their position to the internet and make it available to the whole world. This doesn't have much to do with the actual purpose - better collision prevention between ships at sea.

Kristina Müller,

YACHT editor

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