Autopilot for long distances

SvenglishTommy

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Has anyone had experience of using an autopilot as an alternative to a wind vane self steering system for extended periods, i.e. an atlantic crossing? I guess essentially power consumption is the main issue, so if anyone's done this then then I'd interested to know how much juice you actually needed to replace and how you managed it.

Also experiences of how much of an issue wind direction is, I may be single handed so might have to leave it unatended for long periods.
 
I just completed a 1600 nm passage and I was on autopilot (Raymarine ST6000 Series) all the time. I used manual steering only for close quarter manouvering.

If the sails are well trimmed there is little power consumption. But I have a 65W solar panel fitted too to help. The max time I sailed continously on batteries and the panel and running other than the autopilot: 1 fridge, chartplotter, wind and depth sounder, LED nav lights (at night) and for several hours also the CD radio was about 16 hours. Switching to motor was more to keep up speed after the wind dropped, rather than to charge the batteries. House batteries are 2x145Ah. During that period voltage never dropped below 12.1 (at night). In daylight I had constantly 12.4V or above. I do not have an Amp meter to verify, but I believe that in daylight the 65W solar panel was sufficient for the whole gear and was also charging the batteries a bit.

The experience with wind direction is that it is best to set the autopilot to steer to a wind angle, but as a consequence a wind shift will take you off course (there is an alarm if the autopilot goes off course by more than a defined number of degrees).

Only with strong winds coming from aft of the beam (but care no more than 120 deg) it is possible to steer to a bearing without intervention for hours, in which case you may not bother to have the sails perfectly trimmed all the time.

Steering to a bearing under sail with wind fore of the beam is also possible, but little change of wind direction will require re-trimming the sails, or bearing away when the wind goes too much forward, making almost impossible to relax for a nap.
 
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Has anyone had experience of using an autopilot as an alternative to a wind vane self steering system for extended periods, i.e. an atlantic crossing? I guess essentially power consumption is the main issue, so if anyone's done this then then I'd interested to know how much juice you actually needed to replace and how you managed it.

Also experiences of how much of an issue wind direction is, I may be single handed so might have to leave it unatended for long periods.

I would say single handed long distance offshore don't go there. If you look in MAYS yacht services in Azores the shop has piles of electric autopilots out the back which didn't make the crossing. Alone out in the Atlantic without some sort of automatic self steering you are in a place you don't want to be and a very long way from anywhere to have to steer yourself. Bite the bullet and get a decent wind vane. Zero power draw, doesn't drink coffee and will still work if you loose the batteries or have a close lightning strike. (been both places:eek: elec tiller pilot has not worked since a close strike off south america with a thousand miles to go) After going both ways across solo I would never consider more than a few days offshore without reliable windvane selfsteering. It's well worth it in the long run.
 
I sailed my 40'Bav two handed with ST6000 most of the atlantic there and back and also used an ST6000 on a 38' Sweden for several 00 miles.

On my boat I had an aquair towed gen which provided all the power needed and enough to run fridge/lights/puter/radio etc. Set the boat up so it doesn't need much help is part of approach.

For downwind we used twin headsails on the same roller which is more balanced than using the main as it gets breezy, auto helm was fine up to the point where we hove to, it struggled a bit with huge following breaking seas but so did we.
 
I couldn't relax on a long passage with only an electric auto-pilot. When the weather is bad is when you most need it, and that is when it under most stress and most likely to let you down.
A wind vane, on the other hand, is at its most powerful when the wind gets up. Failures are rare, and often fixable. But when the black box dies mid-ocean, it's dead and gone.
 
Thanks guys, I was wondering if 80 watt solar panels would be enough, and I guess if you can have a fridge going too with 65 watts then power consumption isn't that big an issue.

I understand that electronic equipment is susceptible to damage, but so are thin pieces of metal hanging off the back of the boat.
 
I couldn't relax on a long passage with only an electric auto-pilot. When the weather is bad is when you most need it, and that is when it under most stress and most likely to let you down.
A wind vane, on the other hand, is at its most powerful when the wind gets up. Failures are rare, and often fixable. But when the black box dies mid-ocean, it's dead and gone.
So wind vanes perform well when the **** its the fan? I'd imagined they would lose it a bit in high winds. (Sorry for my ignorance, never used a wind vane before)
 
I understand that electronic equipment is susceptible to damage, but so are thin pieces of metal hanging off the back of the boat.

In marinas it does feel quite vunerable, but anchored or sailing breaking structurally doesn't seem to happen often. The initial fitting needs to be well designed and engineered as they can produce a lot of force.

The thing to remember is that anything mechanical you may well be able to fix enough to be able to keep the boat sailing if there is a failure offshore. There's certainly plenty of time.
Electronics, once they go thats it. And that might well be it until you get to some other part of the world where you can get it fixed or get a new one.

As for high winds, I only know my boat which is heavy long keel but the aries can do much better than i can, rock solid course and can develop a lot of power when the boat speed is up. It's important, though, the get the boat balanced. Which you should do anyway. Do that then get down below with a good book :)
 
A few years back a guy came into our marina in Orkney, his second stop due to total autopilot failure on a none-stop, single handed, round Britain sailing attempt! The response he had from Raymarine was that the tiller pilots he used, (on a boat well inside their specified displacement) were not intended for continuous use.

If you are serious about long distance short handed sailing I would suggest a good wind vane system - you can always use a simple tiller pilot to replace the wind vane to give compass steering for light winds. (If in doubt, see the Monitor manual, downloadable on their web site). Otherwise keep the electric steering for motoring.
 
The response he had from Raymarine was that the tiller pilots he used, (on a boat well inside their specified displacement) were not intended for continuous use.
Tiller, or wheel, pilots are not suitable for continuous offshore conditions.
Powerful integrated under deck pilots are needed. As electronic autopilots have become more reliable, cheaper , and power generation options more prolific, the use of wind vanes are declining.
 
why not a wind vane

you can pick them up cheap now and then on e-bay,i bought mine on e-bay for £85 was not wanted by the new owner of a yacht in norfolk,mine was a hydrovane unit,few bolts missing but ok dont think it had been used since new
 
Powerful integrated under deck pilots are needed. As electronic autopilots have become more reliable, cheaper , and power generation options more prolific, the use of wind vanes are declining.

Hmm , probably are declining , yes. Though maybe not as simple as that. And possibly depends where you look. I wonder if part of the trend comes from more people doing an Atlantic circuit and throwing some money at the boat with that in mind but not looking at a long term cruising lifestyle. Budget certainly has a lot to do with it I think. Skint cruisers will never have an lx autopilot. Imho.
 
Try asking Les Powles if wind vanes work when the wind picks up - he has 3 solo circumnavigations under Solitaire's keel and his Hydrovane steered nearly all of those miles!
Electronic autopilots have their uses - particularly where there are lots of crew and lots of power generating options but to set off on a long sea voyage without being able to steer by the wind which is free and often plentiful seems daft imho. A wind vane will work without any electrical power input month in month out come gales or zephyrs -impervious to the largest breaking seas, heat, rain, lightning strikes etc etc. The best bit of kit I have ever put to sea with - if you have not tried one then you may have pleasures to come. They can also provide a complete back up rudder and steering system which -somewhat contrary to some of the previous postings - explains the steady popularity of wind vanes being fitted to long haul vessels whose owners have read and learnt by the many reports of voyages being abandoned due to steering/rudder failure where there was no back up system.
So don't be vain, get a vane.
82knots.jpg


Robin
Pleiades of Birdham
MXWQ5
 
I couldn't relax on a long passage with only an electric auto-pilot. When the weather is bad is when you most need it, and that is when it under most stress and most likely to let you down.
QUOTE]

Let you down in the sense of gear failure rather than running out of electric power? I have a Simrad 320 hydraulic ram to the quadrant and it has done many miles without murmur over 12 seasons. I reckon it would do 20 days on the trot providing the power is there. Some boats are very difficult to set up with a wind vane - valuable as it unquestionably is, but it's not the only solution. And a pilot can be set to a course, rather than a wind direction.

PWG
 
Self sterring

Well I probably have no right to comment not being an ocean crosser however being a bit of an electronics nutter I would think electric autopilot the way to go. Certainly a wind vane type is a large cost and big installation job and is very vulnerable to damage by following seas. The big advantage is that it brands your boat "deep sea long distance sailor".

I had one of the first Autohelm models many years back. A tiller pilot, it performed wonderfully and seemed to draw about .4 amp when actually adjusting helm and less when going straight. A reasonable sized solar panel should feed that easily. However for bigger boats you need more power from the a/p so more current.
I found I didn't sail alone or long distances and a friend was going on a long voyage and talked me into selling it. I would love another but just can't seem top justify it.

So for my opinion I would go for electric autopilot and carry a spare and have plenty of options re batteries and charging
 
I have a WH autopilot. http://www.whautopilots.com/ It is a rock solid unit used by fishermen Alaska. It is not as fancy as the specific yachty type equipment made but is a very strong unit. I used it to motorsail from La Paz Mexico around Cabo San Lucas and up the coast to San Diego. The electronics run a hydraulic pump that operate a tiller attached directly to the rudder post. I like this system b/c should I have problems with the cable steering I will still have use of the AP till I can get them repaired. I don't know what the electrical consumption was b/c we were motoring most of the way.


I also have a Capehorn windvane but have had problems getting it to work correctly so can't comment on how well that works. I did do a Pacific crossing from Mexico to the Marquesas with a Monitor windvane and didn't have any problems with that.
 
Thanks for all the input, I guess the best option is to have both, especially if single handed. What brought rise to the question is that I've been looking for a new boat, and very few of them seem to have wind vanes, so was wondering how common it was to do the Atlantic crossing with just an AP.
 
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