Winter Sailing

johnalison

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There have been debates about these before, but I think they'd be ineffective. They work on infrared so essentially they pick up differences in temperature. Good for seeing a live body in the water, but a buoy at the same temperature as the water round it wouldn't have much contrast. The other point is that for physical reasons, the resolution of infrared sensors is less than that of optical devices, so the picture is inevitably blurry.

People with military experience have spoken of light amplifying devices (photomultipliers and the like) but the cost of useful kit puts it out of reach for us!

Radar would work for the yachts moored in the Walton channel, but it's relatively low resolution and of course, there's a minimum range within which you get no returns. I've just had one fitted, but I'm not ready to trust it for that kind of navigation!
My radar is quite low, on the stern. I can pick up the Walton channel buoys fairly easily but haven’t tried it in anger. I don’t think the resolution matters very much at the nearest range setting. I think that I have only once entered the Backwaters from out to sea in the dark and I remember that I found it surprisingly difficult, even with a plotter.
 
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AntarcticPilot

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My radar is quite low, on the stern. I can pick up the Walton channel buoys fairly easily but haven’t tried it in anger. I don’t think the resolution matters very much at the nearest range setting. I think that I have only once entered the Backwaters from out to sea in the dark and I remember that I found it surprisingly difficult, even with a plotter.
I must try it some time - when there's plenty of water and good visibility! I need to learn how to adjust it, too. I know the theory well (I worked on ice sounding radars and satellite radar altimeters) but the practice is another matter. It's one thing understanding why a chirped pulse allows a higher resolution and how a SAR can create an image; it's another using it for real!

I probably ought to sign up for a radar course!
 

johnalison

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I must try it some time - when there's plenty of water and good visibility! I need to learn how to adjust it, too. I know the theory well (I worked on ice sounding radars and satellite radar altimeters) but the practice is another matter. It's one thing understanding why a chirped pulse allows a higher resolution and how a SAR can create an image; it's another using it for real!

I probably ought to sign up for a radar course!
I have no doubt that you know a lot more about radar than I do, but a blob on the screen is either there or it isn't. I just whack up the gain until it goes a bit fuzzy and then turn it down a notch or two. The thing about a low mounting is that you don't get sea clutter.
 

AntarcticPilot

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How about going out in daylight and marking the moorings with a waypoint on the plotter?
There are moorings all along the channel. They are laid in lanes, and it's easy enough to get through in daylight, but the swinging circles mean that the path you take one day isn't the one you take the next. The boats lie to both wind and tide, so they don't always lie along the channel; if there's a strong wind they can lie perpendicular to the channel. There's plenty of depth, so there's always a navigable passage, but the track you take varies a lot.
 

AntarcticPilot

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Radar - £2000+. Torch £10-£100.
Indeed. But if you're single handed, operating a torch effectively would be extra work-load, and the cockpit is not the best location from which to use a torch. There's also the issue of night vision; using a torch from the cockpit would give reflections from white surfaces that would spoil night vision.

There are many solutions, but the simplest is to avoid needing them by sticking to daylight in those waters. I'd regard most of the things we've discussed as only appropriate if there was some overwhelming reason to do the passage after dark.

PS: radar bought as part of a bundle nearer £1000! I got it because the incremental cost on top of the plotter I chose was not enormous, in the context of what I was spending.
 

johnalison

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It was just that I was amused by the technological overkill involved in trying to make one's way up the Walton Channel by radar. I'm sure it would be possible, but would a single-hander be willing to weave his way with his eyes glued to a screen. I say 'he' because I'm sure that no woman would be daft enough to try. As pointed out, moored boats are apt to swing around, and I'm far from sure that a radar, even of the modern high-resolution sort, would accurately tell you where the gaps were. Good luck with the new radar.
 

AntarcticPilot

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It was just that I was amused by the technological overkill involved in trying to make one's way up the Walton Channel by radar. I'm sure it would be possible, but would a single-hander be willing to weave his way with his eyes glued to a screen. I say 'he' because I'm sure that no woman would be daft enough to try. As pointed out, moored boats are apt to swing around, and I'm far from sure that a radar, even of the modern high-resolution sort, would accurately tell you where the gaps were. Good luck with the new radar.
It would take something major to make me try! I think I'd take the advice of someone else, and anchor up in Hamford Water rather than try. At the moment the only thing I can imagine might make me try would be one of my dogs falling seriously ill. If it was a human I'd call the Coastguard, but I don't know how they'd react to me calling for a sick or injured dog!

Haven't really tried the radar except in the marina, where there's too much interference from surrounding masts.
 

Aquaboy

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Oh god the dreaded torch..........so bright these days........ but no one else can see!
 

LittleSister

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In my experience a torch isn't necessarily a great help by night on the water. More often than not, I find, the moisture in the air, even when it's not so obviously misty/foggy, disperses most of the light and reflects much back at you. Add that to the loss of night vision, and I think a torch is generally best kept to hand for momentary panic, rather than as a means to find your way through.

I also often find even the lowest available level of instrument lights too bright for best night vision, and on a number of different boats and occasions have rigged up a temporary screen over the offending instruments(s) (e.g. tea towel draped over the instruments, if need be suspended by gaffer tape along the upper edge), raised only occasionally/when required. In this particular challenge one might well need the depth sounder exposed, but the other instruments can be covered most if the time

Moonlight would make all the difference, but it doesn't seem to me to get that dark around the Backwaters, even at the new moon, because of the light spillage from the Felixstowe docks and elsewhere.

An interesting conundrum. I don't have radar but would give it a go - making way dead slow (going backwards while motoring slowly heading into the tide if need be to achieve this); sidelights off (high level lights (nav or anchor) on if available); powerful narrow beam torch at the ready, but turned off; etc. - but then I don't have a 1.6m keel! :D

Thinking further about this, even if there's no tide running it might well be advantageous to proceed stern first: one would have a clearer view astern than forward; less distance between yourself and the potential obstructions/hazards you are trying to see; and if you found something suddenly looming up in your path your acceleration in the opposite direction in forward gear would be faster and with greater directional control.
 

nortada

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Indeed. But if you're single handed, operating a torch effectively would be extra work-load, and the cockpit is not the best location from which to use a torch. There's also the issue of night vision; using a torch from the cockpit would give reflections from white surfaces that would spoil night vision.

There are many solutions, but the simplest is to avoid needing them by sticking to daylight in those waters. I'd regard most of the things we've discussed as only appropriate if there was some overwhelming reason to do the passage after dark.

PS: radar bought as part of a bundle nearer £1000! I got it because the incremental cost on top of the plotter I chose was not enormous, in the context of what I was spending.
Thank you, as one of those targets (boats) on a buoy in the Walton Channel.
 

turnstone

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I'll be in the water through the winter there's some excellent sailing to be had during the winter given that it doesn't get as cold as it used to? Regarding the mooring Buoys in the Walton channel ive noticed that some are being pulled below the surface by strong tides ie first bit of the ebb. I keep to the edge if the visibility is poor but Beaver only draws about a meter.
 

hinch

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Didn't go out of the water last year and won't be this year either. We had some amazing days (and nights!) out on the water last year. We found while the good days are rarer the ones you do get are better than the good summer days.
 

fredrussell

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I blasted up and down the Orwell yesterday. Gusting to F7. Awesome. I love winter sailing, whole river to yourself. Just wrap up warm.
 
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