Coming alongside is the manoeuvre that defines you in the eyes of every sailor sitting in the cockpit of a neighbouring boat. Do it cleanly and nobody notices. Do it badly and three strangers materialise on the pontoon to fend you off and offer advice you did not ask for. The good news is that a tidy arrival is mostly about a slow approach, the right angle, and one clever line. The drama people remember almost always comes from rushing.
I will take you through it the way I wish someone had taken me through it, before I learned the hard way on a windy afternoon in Saint-Quay-Portrieux.
Read the elements before you commit
The first thing to assess, before you touch the throttle, is what the wind and the current are doing to the berth. Wander past once if you can. A flag on a neighbour's stern, the lie of moored boats, a streak of weed on the water, all tell you which way the boat will be pushed.
This matters because your whole plan changes depending on whether the elements set you onto the pontoon or off it. Set on, and the wind does half the work and you barely need engine. Set off, and you must approach more positively and get a line on fast before you are blown clear. In a French marina the tidal stream in the berth is usually slight, but in a river pontoon like the Rance or the Charente it can be strong, and you always come alongside heading into the stronger of wind or current so you can stop against it.
If you have not yet got slow-speed engine control sorted, read basic boat handling under power in a tight French marina first, because everything below assumes you can stop and steer the boat at walking pace.
The approach angle
Come in at a shallow angle, around 20 to 30 degrees to the pontoon, not parallel and not steep. Too parallel and you cannot close the gap. Too steep and you arrive bow-first into the dock and slew the stern out. The shallow angle lets you converge gently and then straighten up as the bow nears the pontoon, killing the angle with a touch of helm and prop wash so the boat slides in flat.
Aim your approach so that your chosen point on the boat, usually amidships, will end up beside the cleat or ring you want. Keep the speed right down, only enough to maintain steerage, which on most yachts is a knot or two. You should feel you are arriving almost too slowly. That is correct.
The midships spring, your secret weapon
Here is the single technique that turns coming alongside from a scramble into a controlled stop. Rig a line from a strong point amidships, your spring, with a crew member ready to step ashore and drop its loop over the nearest cleat the instant you are close.
Once that midships spring is on, you motor gently ahead against it with the helm turned towards the pontoon. The boat cannot go forward because the spring holds it, so instead the engine thrust pins the whole length of the hull snugly against the dock, bow and stern both. The boat sits there, glued alongside, held by one line and a whisper of throttle, while you take your time making fast the rest. If wind or tide is trying to push you off the pontoon, that same ahead-against-the-spring trick holds you firmly on while the crew works.
That one line buys you the most precious thing in berthing: time.
The order of lines
With the boat held on the spring, make the rest fast in an order that keeps it stable. The sequence that prevents the boat swinging out is midships spring first, then stern line, then bow line, then your second spring. Doing the bow first is the classic beginner mistake, because the stern then sails out into the fairway and your neighbour gets a fright.
Lead a bow line and a stern line, then a forward spring and an aft spring so the boat cannot surge fore and aft along the pontoon. In a French marina with any tidal range, leave the lines long enough to let the boat rise and fall, and lead the springs at a shallow angle, roughly 30 to 60 degrees, so they take the surge without coming bar-tight at low water. Visiting a big-range Channel harbour, this is not optional, the boat could hang on a short line as the tide drops.
Crew and communication
Brief the crew before you enter the fairway, never during the manoeuvre. Decide who steps off, which line they take, and which cleat. Agree that they step, not jump, only when the boat is alongside and almost stopped: a broken ankle leaping for a pontoon is a far worse outcome than going round again. Hand signals beat shouting over an engine. Calm and quiet on deck reads as competence and, more importantly, produces it.
If you are arriving cold into an unfamiliar marina, my walkthrough of your first marina arrival in France covers calling ahead and finding your berth so you are not improvising at the last second.
Set on or set off: two different jobs
It is worth labouring the difference, because the two situations want almost opposite handling. When the wind or tide sets you onto the pontoon, your problem is arriving too hard, so you approach more slowly, at a shallower angle, and let the elements close the last gap for you. You can stop a boat-length off and drift gently alongside. The danger is a crunch, so you err on the side of too slow.
When the wind or tide sets you off the pontoon, the opposite is true. Hesitate and you are blown clear before a line is on, so you approach more positively, get that midships spring ashore the moment you are close, and immediately motor ahead against it to pin the boat on while the crew makes fast. Here the danger is being blown back into the fairway, so you commit. Reading which of the two you face, before you start, is the single judgement that decides whether the manoeuvre is easy or fraught.
Fenders and the small stuff
Two practical details save more gelcoat than any amount of helmsmanship. First, set your fenders at the right height for the pontoon you are joining, which in a big-range French harbour means thinking about where the boat will sit at low water, not just now. A fender riding above a high pontoon at low tide protects nothing. Second, coil every line so it runs free when thrown or stepped ashore, with the bitter end made fast on board, because a line that snags as it pays out turns a tidy arrival into a tangle at the worst moment. Have a boat hook to hand too, for retrieving a line dropped in the water or reaching a far cleat.
When it goes wrong, go round again
The mark of a good skipper is not a flawless approach, it is the willingness to abort a bad one. If you come in too fast, at the wrong angle, or a gust catches the bow, do not try to rescue it among the moored boats. Power gently out into clear water, gather yourself, and set up again. Nobody on the pontoon thinks less of a second approach. They think a great deal less of a crunch.
Stern-to berthing on the Mediterranean coast is a separate skill with its own quirks, so when you head south read med mooring with lazy lines before your first attempt. And if you fancy the peace of a buoy instead of a pontoon, picking up a mooring for the first time is the gentler cousin of coming alongside.
Practise the midships spring on a quiet day until dropping that loop over a cleat is second nature. Once it is, coming alongside in France becomes something you do, not something that happens to you.
