Cracks in the sea, what they are and how to deal with them in five moves

Increasingly sudden and virulent phenomena, even in the Mediterranean, groppi can put an ill-prepared crew in serious difficulty. Navigator and sailing coach Luca Sabiu explains how to safely handle such an event during a cruise.

Lumps, an increasingly frequent phenomenon

As we know from seasonal reports and bulletins, unfortunately, the weather situation in the Mediterranean is increasingly complicated, and the trend of disturbances, even virulent ones, is now well established. Of course, forecasts are becoming more and more accurate and detailed, but those who go to sea know that it could happen to find themselves, perhaps during a long sail, in an unexpected thunderstorm formation, the so-called “groppo.” Crops in two words are often well-defined cloud/temporal cumulus where the wind takes sudden and different directions, loaded with water, generally except in special cases the wind intensity never rises above 35 knots.

Here then is where boat and crew preparation in these situations will make all the difference.

It is undeniable that there are two different approaches with respect to encountering and managing a lump at sea. In a regatta, for example, a skipper will take advantage of the rump to accelerate the pace and in the strengthening wind will do anything to pull away from the opponent. On a cruise, on the contrary, a good captain will do everything to avoid it. Those who have participated in an Atlantic regatta or crossing will well remember that the farther west one sails, in the vicinity of the Caribbean, the more frequent these storm systems, often overnight,are and when extensive, are sometimes unavoidable. At the last ARC (Atlantic Rally for Cruisers) the penultimate night we caught as many as seven with no chance to escape and “dribbled” three of them.

In my courses more and more students ask me, “What is the right thing to do in these situations?” I generally answer that there is no right thing. However, it is important to act scrupulously, anticipating situations and thinking about safety, getting crew and boat in trim. After that in the strongest knots you also need to have resilience. So let us see what maneuvers and procedures I have implemented and perfected to handle these situations.

Groppi, on-board electronics come to our aid

I’ve been boating since I was a kid, and I’ve had even 40-foot boats with which I’ve crossed, for example, the Gulf of Lion several times, without even a wind station on board, as they used to do. It can also be done today without any problems. But it is undeniable that electronics are a great support for navigation and over time have changed the way we navigate. So why not take advantage of this important resource?

In the fairly near future, the difference in technology will be: connected boat/unconnected boat. The difference especially for weather purposes is incomparable: having timely and up-to-date weather information means better understanding of the situation, and this information consequently translates into more safety on board.

The role of radar, sentinel of even the lumps

In managing a clump, radar is the main tool. The term “radar “means “Radio Detection And Ranging” and originated for military purposes to be used by both the Air Force and the Navy. Radar emits radio waves through a rotating antenna that will be “our eyes” and give us the distance and angle relative to our position of any object or solid surface in the range of our antenna. And in addition to emitting signals, the radar receives reflected waves from surrounding objects. By knowing the angle relative to the boat of the rotating antenna at the time of transmission, the distance and angle of the same objects can be known. This is by calculating the time the reflection takes to return.

A processor then transforms this information into a visible and understandable image that is depicted on a display in various defined colors. Remember that radar will not tell us the exact nature of that target. Just as it unfortunately does not detect a plastic buoy or a wooden artifact. The range of the radar installed aboard my Class 40 “Flow” is 36 miles.

Incoming groppi: visual and instrumental sighting

A lump can be spotted in two ways: the visual and the instrumental. At night, for example, on an Atlantic crossing, the grooves often come up behind us, and the sky affected by the crowning angle becomes all black and starless. The rest of the sky remains clean except for that part. This is what we will call “visual sighting.” It will then suffice to go down to the chart, and lo and behold, the radar will well identify the conformation of the rump, detecting direction and speed. This is called “instrumental sighting.”

I believe that in the presence of a lump reducing too early is not always an advantage. Boats need to sail fast. Having speed often can avoid uncomfortable situations and the fast boat maneuvers better. However, it is obvious that at some point you will need to reduce or remove for example the spinnaker. And here then is how we will implement our procedure.

Crackles, how to deal with them in five moves

1. Once the lump is sighted, we activate the first Guard Zone on the radar. This is a boundary, a safety perimeter that we can choose what distance (range) to place on the display.

Next we will place the second Guard Zone, which unlike the first always starts from the center of the screen and thus from our position. I point out that we are always in the center of the radar screen.

It is important to know that all radars today have a “call EBL” function, which stands for “Electronic Bearing Line,” or a bearing line that tells us the relative angle to our boat. By pointing this line toward the lump or target, it will be possible to determine whether the bearing remains constant or not. Now the two guard zones have become perimeters and mark boundaries that will give us a better understanding of the movement of the rump. The device will then sound an alarm when the croup crosses these “protection thresholds.”

Maximum concentration and no mistakes on deck

Let us now look at the procedure we adopt in the event of a crotch during non-racing sailing. The loggerhead enters Guard Zone 1, which on the night we positioned, for example, at 12 miles, and has a trajectory going toward Guard Zone 2. So it heads toward us, and the space between Guard Zone 1 and Guard Zone 2 is the time to act.

2. I state to the crew the lump, useless to hide it because a few minutes from now the “blender” will turn on. Everyone had better be ready for action, or at least be safe even below deck, as this is not the time to do activities that could be dangerous, such as having stoves on, etc. If they want to go out to the cockpit, they will have to obligatorily tie up.

3. The more my eyes see, the less time it will take me to find the right circuits at the tree. There is no point in working in the dark and losing valuable time. On board, we mounted an LED light under the radar that perfectly illuminates the entire bow triangle and mast area.

4. We then lower the spinnaker or gennaker as per procedure: messing up at that time could compromise the sail or worse risk getting hurt. An important rule to always remember and apply in these conditions is, “the higher the intensity of the conditions, the more you have to stick to the method.”

Backstrap, reefing hand and boom restraint

I want the boat to always look maneuverable even inside the croup, and without a headsail this does not happen. That’s why we hoist the foresail, a lean, hard, strong, easy-to-manage sail. Aboard “Flow,” the foresail when not working, always remains engorged and ready on deck.

We then take reefers to the mainsail, whether one or more hands we will decide at the time, primary objective now is to trim the boat.

5. I sail in the croup with boom restraint at mark and in safe gait. Remember that groping often requires more mental clarity than technique-it is as if groping stimulates the head more than the skipper’s hands. Calm and order and everything will be fine.

I keep a close eye on the direction and speed of the system: the clumps, in English known as “squalls” are sometimes very fast. The famous night of the seven lumps we mentioned earlier had an average duration of about 12 minutes each.

In those moments there is no quintessential right choice; each commander has his own. This procedure is now well-established for me, but each of us must find the one most akin to our skills and abilities. And sometimes we also have to adapt it to the kind of boat and crew we sail with. It is important in any case to plan it beforehand and have it clear in your head because those moments are very fast-paced and the action must be tied to a clear execution in order not to be overwhelmed by the event.

Happy miles to all!

Comm. Luca Sabiu

• Also read this article by Luca Sabiu: Asymmetrical gennaker cruising. Better sock or whisk?