German Navy: Discussion on encounters between submarines and water sports enthusiasts

YACHT: How did this meeting come about?

Captain Jasper: To give all the regatta fleets a wide berth, we would have had to sail all the way round Stollergrund. Ultimately, however, we are out at sea to fulfil our mission. We have to reach a destination by a specific time. We therefore took the route we always take and prepared ourselves for heavy traffic and for coming close to recreational craft. On the way, we came across this group of sailors, who weren’t actually taking part in a regatta but were waiting for the wind. The bridge control responded to this and reduced our speed. As you can see in the video, we were travelling very, very slowly. We then continued on a straight course at the reduced speed.

Were there any other reactions afterwards apart from this Instagram post?

No. It was completely harmless, after all. One of the sailors’ safety boats was there too, but it didn’t make any contact with us at all. As far as I’m concerned, we sailed very slowly through the field, gave a friendly wave – and then, as far as I was concerned, that was the end of the incident.

How fast are you driving there, then?

I can’t say for certain, but it must have been about three to four knots. The advantage is that, as we have an electric motor, our stopping distance is extremely short. If we come to a halt whilst travelling at three knots, we’ll come to a standstill within less than the length of the boat. So we always had the option of reacting quickly if necessary – and that, of course, also provides a sense of security.

That must have been exciting for both sides…

… That said, the fascination with submarines is mutual. In our experience, whenever a submarine is in the area, pleasure craft often come closer to have a look.

Isn't that dangerous?

I think a lot of people underestimate just how big we actually are, even underwater...

What would you expect from sailors who are nearby? You just said that they sometimes like to come closer. Where is the line – when does it start to restrict your manoeuvrability, or when does it become downright dangerous?

Everything that happens in the immediate area ahead of us is relevant to us. After all, we don’t want to put anyone at risk, and we certainly don’t want to cause an accident involving a pleasure craft. That’s why, in my view, the most important thing is to keep clear of the area ahead. What we find difficult is assessing the manoeuvrability of pleasure craft, as theirs is much greater than ours.

For sailors, on the other hand, it is difficult to tell where the submarine begins and where it ends. Is there any clue to help with this? Anything that might give it away?

Most of it is hidden from view. What you see when the submarine surfaces is just a bit of the hull. But there’s over a metre more to the left and right – and, of course, the steel hull beneath that.

Nickelsdorf Football Club: As a rough guide, you could say that the boat is as wide as the tower rudders you can see at the top. You can see this quite clearly in the video as well. Those front depth rudders on the tower – the hull is roughly that wide underneath them. If you also keep a distance of five metres, you’ll be on the safe side.

Have you ever noticed that pleasure boats approach when only the periscope is visible above the water?

Yes, but that’s interesting too, of course. What a sight – being able to take a selfie with the periscope whilst on your own sailing boat or motorboat. People sometimes really underestimate the fact that there are still nearly two thousand tonnes of steel attached to it.

So people actually come right up to the telescope and have a look?

Captain Jasper: Yes, yes. But it’s understandable, really. Most people probably don’t even realise what it is at first. There’s something moving through the water – so you go over and have a look.

Nickelsdorf Football Club: If you spot a submarine’s periscope, feel free to swim past and wave or give a flag salute – that’s perfectly fine. You should, however, keep your distance.

Captain Jasper: For us, navigating at periscope depth is very demanding. We have to maintain the depth precisely. The periscope protrudes by perhaps about one metre, and the boat – or rather, the tower – begins just two metres below that. This is a situation that requires our utmost concentration and in which we have to adhere to specific procedures and distances. We really don’t want anyone too close to us, because we always want to ensure that we can surface from the periscope depth. And if someone’s taking a selfie with the periscope at that very moment, we can’t do that, of course. But I really want to avoid giving the wrong impression here: 99 out of 100 encounters are positive in this sense. Then someone comes over, salutes with a flag, waves and is simply delighted – and that’s a lovely experience for us too, because it’s a form of appreciation. It’s extremely rare for an encounter to become genuinely unsafe.

How likely is it, then, that a submarine would happen to be surfacing in that sailing area?

We can’t dive everywhere, because we need a certain depth of water to do so. We can dive in Eckernförde Bay. In the Stollergrund Channel, however, it’s too shallow.

And when you’re out driving, what proportion of the time do you spend driving on tarmac?

It’s impossible to make a blanket statement about that. For one thing, as I said, we need sufficient water depth. Then, of course, it has to suit the job at hand. During Kiel Week, for example, we needed to get into the Arsenal as quickly as possible. Diving wasn’t necessary at all in that case. But otherwise, whenever we have the opportunity, we often dive whilst transiting.

When you resurface – will you have a clear picture of what’s happening above you?

We first descend to periscope depth. And only then do we surface. This means that by the time an outside observer can clearly see the submarine, we have long since seen everything. So, before surfacing, we make sure that we do not create a dangerous situation with other vessels.

Is there such a thing as an emergency dive manoeuvre, where you have to act particularly quickly and don’t have the chance to check what’s going on beforehand?

You always have the intermediate step involving the periscope depth. There is only an emergency procedure in case the boat is damaged.

Nickelsdorf Football Club: Then there is what is known as an emergency inflation system – put simply, it uses propellant charges or generators to ensure that the boat rises to the surface. That would actually be the moment when the situation on the surface might not be entirely clear. But this is really only for an absolute emergency. And it has never happened before.

So nobody needs to worry that a submarine might suddenly turn up and get in the way…

No. For us on the submarine, it is of the utmost importance to know what is happening on the surface. To this end, the sub is equipped with a wide variety of sensors. And this transition from deep submersion to just below the surface is a particularly delicate moment for us. From that point on, we can see. And we prepare for this with the utmost care, using every sensor at our disposal. Water sports enthusiasts can say with a clear conscience: there are more dangerous things out there.

Captain Jasper: Nor is it the case that we only start assessing the situation when we’re about to surface. Our aim is, in fact, always to know what’s going on around us. There’s a good saying: ‘A submerged submarine must always give way.’ Because, ultimately, we have to assume that nobody else can see us. This means it is entirely our responsibility to resolve all situations in such a way that they do not pose a danger to anyone. That is why we always maintain situational awareness – not just at the moment when we say: ‘Right, we’re surfacing now.’

Nickelsdorf Football Club: Our aim is always to be aware of what is happening on the surface. And good seamanship is our top priority. We know the rules; we also know who has the right of way. And we recognise that the sea is our shared economic, living, operational and recreational space. When seafarers meet, they therefore behave in a spirit of camaraderie – and that is indeed how we have almost always found it to be. From my ten years of submarine service, I can’t really say anything to the contrary. Perhaps I would like a little more protection from prying eyes.

How much distance do you actually need to keep from the surface when you’re diving?

The so-called safety depth. The submarine itself is about twelve metres high from the lower edge of the keel to the top of the conning tower. The safety depth requires that we also have sufficient water above us. This is the distance above the keel that we need to ensure nothing happens – even if there were to be a direct overflow, which we naturally want to avoid. And to allay any concerns straight away: we don’t base our calculations on a sailing boat, but on a tanker – in other words, on the vessel with the greatest draught that we expect to encounter in the lake area. So sailing boats are not at risk.

Your squadron is the only one in Germany – how many submarines are in it?

Six.

And how often are they out and about?

Roughly speaking, you could say: three to four months a year.

And then mainly here in the Baltic Sea region?

Yes. In principle, worldwide deployment is planned and possible. We have spent a lot of time in the Mediterranean, and we have also been to the US East Coast. At the moment, however, the focus is on the Baltic Sea region and the North Atlantic.

And what is the difference between driving on the surface and driving underwater?

As a general rule, you could say that submarines always travel submerged – unless they’re heading somewhere and are in a hurry. But the actual purpose of a submarine – depending on its operational and mission profile – is, of course, to be submerged. It’s quite common for us to submerge just outside the harbour and not resurface until we reach the next one.

Can you see the submarine on your AIS if you’re sailing? And if so, can you see it even when it’s submerged?

Captain Jasper: As a warship, we always have the option of switching on our AIS. The decision is made on a mission-by-mission and situation-by-situation basis. So: maybe yes, maybe no. It depends.

Nickelsdorf Football Club: My general instruction is: AIS off. Because not everyone should know where every warship is at all times. But of course, the commander will decide to switch it on if navigational safety so requires. Whilst submerged, however, it is simply not possible to transmit a signal.

And how many submarines do the other countries bordering the Baltic Sea have in service?

It’s a quick story: they’re basically just the Swedish submarines and those of the Russian Navy. Poland also has submarines, but they’re very old and are due to be replaced.

Are emergency call-outs on the rise now – compared with five or six years ago, partly as a result of the general reorganisation of the armed forces?

No, I wouldn’t say there’s more of it, but the focus is more on the Baltic Sea and the North Atlantic. We used to be in the Mediterranean much more often.

The Navy also trains its officers on sailing yachts; we’ve just reported that new Sun Beams from Austria have been commissioned for this purpose. Is it fair to say that every submarine commander has spent time on a sailing boat at some point, as this forms part of their training?

Captain Jasper: That’s a safe assumption. There may always be exceptions in individual careers. But, as a general rule, every naval officer holds a naval sailing certificate, which could also be converted into a civilian sailing licence. That is the basic principle, because sailing forms part of nautical training.

Nickelsdorf Football Club: And everyone has a motorboat licence. Exactly. And when you see that in the context of the Kieler Woche, everyone will understand why it makes sense for the Navy to provide training on sailing boats as well. That’s why, amongst other things, we’ve always stood up for the Gorch Fock, despite all the opposition. There’s hardly a better way to explain to young cadets the influence nature has on our profession, despite all the technology, and just how important teamwork and solidarity are. You can learn that perfectly well on a sailing boat.

Captain Jasper: And as I’ve just hinted at: the decision to become a soldier and then join the Navy is often linked to a certain affinity for the water. We have lots of comrades who also go sailing in their spare time.