Docking stern-to in crosswind

[Lodesman]

Originally Posted by dokondr

Hi all,

I have come across an interesting docking question. Please share your ideas on the following:

*** Question:
How would you approach pontoon in the situation on the sketch below? You need to park stern to pontoon in a narrow slot between other boats in 20Kn crosswind. Boat propeller is right-handed, propwalk in reverse is to port. Will you approach upwind or downwind? Closer to the boats or closer to the wall? When will you start turning?

~~~~~~~|||~~~~~~~~~~~~~~
~~~~~~~|||~~~~~~~~~~~~~~
~~~~~~Wind 20Kn~~~~~~~~~~
~~~~~~~|||~~~~~~~~~~~~~~
~~~~~~~\|/~~~~~~~~~~~~~~
~~~~~~~~~~~~~~~~~~~~~~~
boats~~~~~~~~~~~~~~~~~~~~
—————\~~~~~~~|wall
—————/~~~~~~~|
—————\~~~~~~~|
—————/~~~~~~~|
dock here with stern to pontoon
—————\~~~~~~~|
—————/~~~~~~~|
—————\~~~~~~~|
—————/~~~~~~~|
—————\~~~~~~~|
—————/~~~~~~~|
===== wall =======

What is the bow attachment? Pilings? Mooring buoy? Trot line? or Anchor?
Is this a hypothetical exercise, or do you really have to deal with this situation? Most boats going in reverse will have the stern seek the wind. Many sailboats struggle to overcome propwalk in reverse. If we're talking about a real boat, then how does it handle in these situations?

[desodave]

Originally Posted by dokondr

When you turn around, go upwind, stop a 1 or 1.5 boat length away from a slot and then reverse into a slot - this will fail in 20Kn of wind. Why ? Very simple: you won't be able to get enough speed to steer the boat and will loose your bow right away.
Also note, that probability of tight turning 180 degrees in 20 Kn crosswind is quite low as well :-)


In case you reverse from the very beginning of the channel - you will loose your bow even earlier.

With respect I don't agree -but maybe we have different boats. As stated I make a similar turn into a fairway in my home marina and we have regular 10-20 knot crosswinds. You have not provided the fairway width or length in your "problem" and those are relevant. It is a timing issue and the timing is tighter as the wind speed increases. And especially with a narrow slot I would NOT try it unless I can see an escape route and a bailout point short of smashing into something.

[jhulmer]

I have never tried this but will one day when forced too.

The maneuver is call dredging if I recall correctly and big ships use it from time to time in heavy wind.

In your scenario, you would back down the channel with your bow to the wind. l would power back and use forward thrust to keep the bow into the wind.

Or as described go past the slip and turn around, but tricky with that much wind in tight quarters.

Have your anchor ready. if you have a windless control in the cockpit this is much easier. If you have a rope road then run it back to the cockpit winch.

The idea is to position the boat to back into the slip bow to wind. Then drop the anchor so it will drag, not set. This will take some practice to figure out how much you can let out without the anchor setting.

This will add drag to the bow to prevent it from blowing off as you back into the slip.

If you have too much dredge raise the anchor a little. Not enough dredge let out a little scope.

I have heard about the old guys using this method with impressive success. I have got to give a go some day.

[Altopo53]

Prop direction is crutial, just as said. But - why do you need to go stern to in such conditions? Why take a chance? Just enter with the bow. You can turn boat around later when there is no wind. Just my grain of salt.

[TrentePieds]

@ #48

Pretty dodgy in a small boat in a tight marina. While you could "dredge" with your chain only, having removed the anchor itself, and that would indeed hold your head to wind, turning into the slip while going astern would be nigh impossible IMO.

If you try it, be VERY careful - and be VERY sure you are properly insured :-)!

TP

[LongRange]

Originally Posted by jhulmer

The idea is to position the boat to back into the slip bow to wind. Then drop the anchor so it will drag, not set. This will take some practice to figure out how much you can let out without the anchor setting.

...

I have heard about the old guys using this method with impressive success. I have got to give a go some day.

Ironically, in many Mediterranean harbours this kind of "dredging" is done quite frequently, if inadvertently, usually by inexperienced charterers who haven't quite grasped the concept of scope

The net effect is to hook one or two anchor chains from other boats, as the "dredgers" slowly drift across their bows, leading to a tangled mess, lots of shouting, gesticulating, and European culture

[Nicklaing]

With a Lagoon 450 and no bow thrusters this is of course is my nightmare and being based in Croatia I carry out this manoeuvre, with the wind in the wrong direction, several times each season.

First of all a ton of fenders on leaward side, plus some off the stern.

Come in stern first. Bow up wind. As close to upwind wall/boat as you dare. Try and keep that angle as far as you can coming into space. Once you start to straighten up the wind will take your bow if it has not already started to move the whole boat.

Straighten up when you need to coming astern towards pontoon. You are going to be blown sideways so get windward stern line on first and as soon as that is on port engine ahead and wheel over to starboard.

Then get Leaward line on. Both engines ahead. Starboard wheel. Then concentrate on bow lines.

Lots of fenders, a few prayers and a shot of whisky afterwards seems to help!

[sailorladd]

An interesting situation, and without seeing it in real life, hard to imagine the scenario from the diagram (cleverly described on keyboard BTW , but my initial reaction to situations like these is to try to round up (under power obviously) into the wind and be able to pick up a mooring from the wall, and once secured, I would lead a mooring line attached from my stern to the same mooring point my bow was attached to. I would then cast off my bow line and being VERY mindful of my stern line (engine!! propellor!!) allow the wind to turn my bow to port and swing around (with a little help from my engine) and across to the pontoon mooring ...

[Bullshooter]

Originally Posted by Nicklaing

With a Lagoon 450 and no bow thrusters this is of course is my nightmare and being based in Croatia I carry out this manoeuvre, with the wind in the wrong direction, several times each season.

First of all a ton of fenders on leaward side, plus some off the stern.

Come in stern first. Bow up wind. As close to upwind wall/boat as you dare. Try and keep that angle as far as you can coming into space. Once you start to straighten up the wind will take your bow if it has not already started to move the whole boat.

Straighten up when you need to coming astern towards pontoon. You are going to be blown sideways so get windward stern line on first and as soon as that is on port engine ahead and wheel over to starboard.

Then get Leaward line on. Both engines ahead. Starboard wheel. Then concentrate on bow lines.

Lots of fenders, a few prayers and a shot of whisky afterwards seems to help!

I follow your post except for the "wheel over to starboard" part. That would seemingly push your boat the downwind into the boat to your starboard side, unless I misunderstood. I would think wheel to port, if anything.

[jhulmer]

Originally Posted by LongRange

Ironically, in many Mediterranean harbours this kind of "dredging" is done quite frequently, if inadvertently, usually by inexperienced charterers who haven't quite grasped the concept of scope

The net effect is to hook one or two anchor chains from other boats, as the "dredgers" slowly drift across their bows, leading to a tangled mess, lots of shouting, gesticulating, and European culture

YUP! This is a common practice in the BVI as well and with great success!

[Lcdr47]

One thing that has helped me in the past is to let go a short scope of anchor, sufficient to stop the bow from swinging but short enough to drag if necessary. Alternatively, let go a long scope and check your progress paying out as you go, until you can get a windward stern line on.

[2big2small]

The trouble with dropping an anchor in a marina is that the bottom is very likely to be foul. I wouldn’t take the risk of being snagged in the middle of a maneuver.

[galway007]

Drop 2 anchors. One windward to pontoon and one outside the scope of the other boats and then let the wind push you while you feed out anchor lines to the two anchors until you are in line with your berth and give a tiny little reverse to get into slot.

Alternative method: drop an anchor to winward outside the scope of the docked vessels. Feed out this anchor line as you nose in and tie a line to your berthing spot on the dock. Then use the outside line to pull yourself off the pontoon and switch the two lines bow-stern and stern-bow and pull yourself around so you're bow out- stern to and use the dock line to pull yourself in.

Either method will have you safely docked with very little risk and after you're docked you can tie a little bowline loop with a little piece of chain to hold the lines down on the bottom overnight with it still tied to a cleat ondeck and tomorrow - you're away easily to retrieve your two picnic lunch anchors and keep cruising.

[BrotherT]

Hi. A couple of learnings from a recent 6 month trip in the Med on a monohull that may help. Firstly, if possible wait until the wind drops, even slightly, or try go in between gusts. Time of day matters sometimes, and ask the marina staff for their opinion. Secondly, ALWAYS motor stern first into the wind in a narrow channel, even in a cross-wind, because the wind will push your bow one side or the other but your stern is broad and the rest of the boat is pulled in the direction steered. Thirdly, motor reasonably quickly with decent way astern because you can stop by going ahead quickly and more effectively. Fourthly, all fenders out and a bowline led aft that you can throw to windward boat if possible as you go astern. Stern lines ready being assumed, but make windward stern line fast first! Lastly, if there are enough people to assist ashore on the windward boat (marina staff can be called in advance to assist), I would even consider motoring astern to hold station off the entrance to the slot and passing port windward stern and bow lines to windward boat and warping her back into the mooring if feasible under power in the configuration... Saw some collision disasters in narrow marinas like ACI in Korcula with impatient charterers even trying to leave bow first in strong cross winds when marina staff recommended a two hour wait until wind likely to drop off. Also, it can be worthwhile to have a test run up the channel into the wind to see how she handles the conditions first before attempting to get into the turn. Good luck!