Getting out of a finger berth astern (basic prop walk question)

[FairweatherDave]

This weekend was the first time I have gone out of a finger berth astern. Since my prop walk kicks to port I was concerned I would be rubbing fenders with my neighbour (moored starboard side to). My concern was due to a lack of practice as we dodge marinas on the whole. I use Duncan Wells Stress Free Sailing book which recommended a bow bridle to keep the boat parallel to the pontoon but I was concerned that as soon as I started moving the prop walk would kick in and I'd be off to port before gaining steerage. My question is does rigging the bow bridle and driving astern against it before slipping it stop prop walk (as the prop is moving water about.....)
If people don't know what a bow bridle is there's a video by DW here

I'm happy springing off from alongside berths but realised I haven't done finger berths.
Cheers for any pointers
PS Tide and wind were negligible and nothing bad happened, but I wish I had understood my prop walk and bridle theory better, just for peace of mind beforehand

 

[Plum]

Hi, in my experience, having some sort of quick release method of slipping your lines from on board has no bearing on the prop walk. An added complication when single handed, if engaging astern before slipping, is that while you are busy hauling in all that line the boat is moving astern with no one on the helm and no one looking out for other boats manoeuvring.

Www.solocoastalsailing.co.uk

 

[Sandy]

May I suggest you hire an Instructor for a day and spend the time "pontoon bashing" you will be amazed at what you can achieve with a bit of tuition.

Duncan's book is brilliant and I was able to thank him personally at the Southampton Boat Show in 2019 for writing it. I particularly like his trick of raising the main while underway with the Genoa driving the boat.

 

[V1701]

What boat do you have? Older, long keel designs are terrible in reverse but a modern fin keel will steer well in reverse pretty much as soon as you start moving so if you have the latter I wouldn't worry too much or over think it...

 

[Catalina36]

I was plagued with it for years until I built this and added proportional control to it and the bow thruster. I'm in the process of multi-roling it as an electric outboard.

 

[Stemar]

I like that. A boat that's wayward going astern is another argument in favour of carrying the flubber's outboard on a transom bracket - removable stern thruster!

 

[Catalina36]

I like that. A boat that's wayward going astern is another argument in favour of carrying the flubber's outboard on a transom bracket - removable stern thruster!

I did weigh up that option but the problem is starting and controlling it while also trying to do all the other bits. This way gives simple control at the helm and also operates in both directions.

 

[TernVI]

May I suggest you hire an Instructor for a day and spend the time "pontoon bashing" you will be amazed at what you can achieve with a bit of tuition.

Duncan's book is brilliant and I was able to thank him personally at the Southampton Boat Show in 2019 for writing it. I particularly like his trick of raising the main while underway with the Genoa driving the boat.

Or just team up with a mate and set aside a couple of 2/3 hour sessions.
Read the books, make time to practice.
Find somewhere with some empty pontoon or just lay a couple of buoys.

An extra person on the boat to observe what's happening from a different POV is very valuable.
And they can fend off of course!

If you sail with another person, invest time in getting them better at close-quarters.

Whenever I get on a boat that's new to me or I haven't sailed it for a while, I like to spend a bit of time doing 3 point turns in open water, to get the feel of how it handles.

In tight spaces, there is usually a way of using a warp to control and turn the boat.

 

[FairweatherDave]

What boat do you have? Older, long keel designs are terrible in reverse but a modern fin keel will steer well in reverse pretty much as soon as you start moving so if you have the latter I wouldn't worry too much or over think it...

Boat is a Westerly Konsort (bilge keel).
I would agree that I was overthinking simply because I was in a marina which is an unfamiliar environment. I'd love to go pontoon bashing with an instructor sometime Sandy, it sits on the list of things to do .
But to summarise so far.... no one except Plum has said holding the boat in position on a bow bridle will stop a bit of prop walk once the bridle is slipped. The boat needs to actually be moving over the ground before the rudder gains steerage. (Yet using the rudder while held on the bridle (or spring) will alter the position of the boat relative to the pontoon).

 

[johnalison]

The standard way of countering prop-walk in reverse is to give the throttle a hefty dose of power to get the boat moving, and then knock it into neutral, when the boat will steer easily. My prop walk is relatively slight but noticeable and I use this technique regularly. If you are lucky, once you have established control, you can re-engage gear and the boat will steer well enough with the helm well across.

 

[[3889]]

Not really sure how the bow bridle helps in keeping you off the pontoon, it just prevents movement astern. Good tip on using a single winch for both ends of a line, though.
Exiting a finger I'd have a bow spring rigged to slip, burst of ahead to prop wash the stern as far off as possible ( fendering against neighbour's boat) then engage astern, slipping the spring. If the berth is very narrow so no meaningful angle can be gained, rig a slip to the neighbouring boat and have crew walk along your deck adjusting the angle of the line to best hold you off the finger. Then slip once clear.

 

[laika]

My question is does rigging the bow bridle and driving astern against it before slipping it stop prop walk (as the prop is moving water about.....)

Not in my experience. Once the bridle is slipped you'll be subject to prop walk until you have sufficient way on, although having the revs on when you slip will mean you'll get way on a little quicker. With a reasonably wide fairway and not much of a contrary breeze I can defeat my prop walk by having confidence and giving it some welly but I've found the better approach is usually:
- If your prop walk is turning you the way you don't want to go but the wind is pushing your bow the right way, creep out with lots of neutral and let the wind do the work until you can engage forward
- If the wind and prop walk are both conspiring against you, let them have their way and change your plan. If you wanted to leave the fairway forward, go out astern instead.
...all of course assuming there's not a tide running through to completely change the game ;-) .

+1 for Mr. Wells's excellent book. I too have given him my positive feedback at one of the boat shows.

 

[Leighb]

We found with a long keel yacht that it was totally unpredictable astern under power. The answer, for us at least, was not to use power at all until clear of the berth. My wife took the helm with the rudder slightly in the direction that the stern should go. I then pushed the boat out of the berth also shoving the boat in the required direction, I got on as the bow was passing the end of the finger and then power was used to kick the stern round and motor out of the marina.
Our marina has tide running through it which does complicate things, and sometimes the combination of wind and tide meant that plan B, go another time , had to be adopted.

We now have a twin screw motor boat so departing the berth is easy, arriving however can be tricky we find!

 

[FairweatherDave]

Not in my experience. Once the bridle is slipped you'll be subject to prop walk until you have sufficient way on, although having the revs on when you slip will mean you'll get way on a little quicker.

Thanks all, that is really the detail I was focused on.

To give more context, it was a tight berth next to a rather well kept mobo. I got my family well organised for the departure with roving fender and dedicated line retriever etc. It was complete overkill and none of them could see what I was worried about. However one of my crew can get rather anxious and once that happens they tend to hide below and not come out for a while, which doesn't help my concentration....., or my other crews concentration .....families eh!

PS In my hunt for info before posting I also came across Simon Jinks RYA you tube stuff and thought it good (it is obviously basic). But one thing I learnt was how the pivot point moves aft as you go astern.

 

[[3889]]

Thanks all, that is really the detail I was focused on.

To give more context, it was a tight berth next to a rather well kept mobo. I got my family well organised for the departure with roving fender and dedicated line retriever etc. It was complete overkill and none of them could see what I was worried about. However one of my crew can get rather anxious and once that happens they tend to hide below and not come out for a while, which doesn't help my concentration....., or my other crews concentration .....families eh!

PS In my hunt for info before posting I also came across Simon Jinks RYA you tube stuff and thought it good (it is obviously basic). But one thing I learnt was how the pivot point moves aft as you go astern.

Rule of thumb for AWBs is pivot point at mast going ahead and at companionway going astern.

 

[Catalina36]

We found with a long keel yacht that it was totally unpredictable astern under power. The answer, for us at least, was not to use power at all until clear of the berth. My wife took the helm with the rudder slightly in the direction that the stern should go. I then pushed the boat out of the berth also shoving the boat in the required direction, I got on as the bow was passing the end of the finger and then power was used to kick the stern round and motor out of the marina.
Our marina has tide running through it which does complicate things, and sometimes the combination of wind and tide meant that plan B, go another time , had to be adopted.

We now have a twin screw motor boat so departing the berth is easy, arriving however can be tricky we find!

"arriving however can be tricky we find!"

Exactly so. Prop walk happens whenever astern is engaged, including when it's necessary to take way of the boat as you turn to enter the berth. If that coincides with a breeze blowing you off it's very difficult to stop the boat wandering off before you've got close enough to get a line ashore. Hence the device in #5. The boat now goes where I want it to go, not where it decides.

 

[Poignard]

The worst thing I can do with my Twister is to reverse out of a berth slowly.
Duncan Wells bow bridle technique helps because you can have power on before you slip so you quickly get out into the fairway before prop walk and bow windage have their wicked way with you

 

[Deleted member 36384]

In the OPs case, if I have room or weather on my port side, I let the stern swing out and when well clear of the pontoon engage astern. In most cases that works fine. In tight situations I have warped my boat back and set up slips to the bow and midship cleats. The kick on my boat is significant and I need a bit of way on before the rudder works. The advise previously about getting way astern (a strenboard) then going into neutral is excellent for the short duration you the boat has to move to clear the other boat. On my own boat, I use lots of revs in bursts, both forward and astern, with one hand on the wheel and one hand on the throttle, to control the boat going backwards, usually in a serious of small scallop motions but in a general backwards direction. I concentrate on the bow as that is the big swinger.

It just takes practise. I have used empty hammerheads to practise in favour of practising between finger pontoons. No one appears to mind if there are no boats nearby. I have always ask the marina if intending to practise.

 

[capnsensible]

I think it looks neat and I'm gonna try it a bit. I'm a fan of having a big ball fender for use in mooring situations. For that technique, I'm gonna rig it on the inboard bow just aft of the pulpit so it just touches the water. That, I reckon, will be a great help in protecting the flare of the bow. A few goes should do it, then Mrs S and myself can swap around for some more practice. ?

 

[neil1967]

At our home berth we are normally berthed starboard side to and our prop kicks to port. We have an Oyster 406, so a long fin keel, and I consider the prop walk an advantage in this situation - it pulls the back of the boat to port so that when I am out of the berth I am pointing the right way down the fairway. Our technique is to slip the engine into reverse while still tied up then to remove the midships spring using the engine to prevent us drifting/being blown forwards onto the pontoon, then simultaineously slip the bow and stern lines, and we glide backwards turning to port. It is more tricky if the wind is blowing us off - we actually need to get more power on to get out of the berth quicker before we are blown on to the large mobo to our port.