Wind vane for a large 20t+/50ft+ boat?

[Vespy]

Hey,



I'm a newbie on these forums, and yes, I've searched.


Wind vanes seem a really great way to spare your autopilot the wear and tear, and a bonus for your batteries... I imagine that on larger boats, (let's say a 50 foot blue water 20 ton cruiser), a wind vane would have to be significantly large to counter all the other forces working on the boat.



Is there a point in size and weight where a wind vane is no longer productive?



Can a wind vane and an autopilot work together on a large boat? (leave the autopilot a wide target variance, let the vane do most of the work?)


Or is it ultimately just another complication that you need to worry about, which grants little to no benefit on larger boats?



And ultimately, to sum up the 3 questions above, is there any point to using wind vanes on ships above 20t and 50ft?



--


Again, apologies if this has been answered before, I've read through hundreds of posts, but it all concerned small boats...

[Enfant Du Vent]

Ahoy Vespy:
My personal experience is from the late 1980s, when I used an Aries wind vane on my 32' 6ton sloop.

I called the designer/builder to explain the size of my boat and ask which model would be the best fit. I was told he only made ONE size. He explained that because it was attached to the tiller or wheel the only effort it had to match was the strength of a helmsman.

In 1000s of miles of offshore sailing it worked very well. Because of the distance from land, being a few miles off course was irrelevant. And with a pilot compass mounted over my bunk, I didn't have to go up on deck to check whether the wind direction had shifted significantly.

I can't comment on it reducing wear and tear or battery drain of an autopilot because I never felt the need to have an autopilot.


PS: As crew on many sailboats with autopilots, I can say that the unwritten rule seemed to be that the motor for the autopilot be installed under the bunk of the owner's wife. This would result in the owner's wife sticking her head out the hatch at 2 am and saying, "Will you please turn the damned autopilot off, I'm trying to sleep."

[Vespy]

Originally Posted by Enfant Du Vent

"Will you please turn the damned autopilot off, I'm trying to sleep."

Ha!



It's true, an autopilot on a larger boats can be quite loud by itself on a calm night passage, especially in the cabins... I think that is the noise that really drove my mother away from doing longer passages with my dad...

[Tillsbury]

You're specifying what is effectively the upper limit on what the windvane manufacturers suggest is appropriate. A 50ft 20t boat can use many of the windvanes. I think they tend not to be the same for something over 60 feet. On the other hand boats of over 60 feet generally have very significant electrical systems and generators, so the use of an electric autopilot wouldn't be anything like the same issue. I think that's where things lie right now, so it's presumably not worthwhile for a manufacturer to make a windvane suitable for a 65ft boat as the market would be extremely small.

[sailorphil9]

Our boat is steel and displacement varies 26-29 tons depending on tanks etc. We are fin keel, draft 2.84 m (9 feet). Length on deck 14.6 m (50').

Currently in New Zealand after Atlantic & Pacific crossings under Hydrovane, fitted in 2017. Before that I sailed for 12 years including UK-Brazil and back in 2006 with an electro-hydraulic autopilot (still working) which draws 15 amps (12V) at peak load.

The Hydrovane (off centre mount) has been a huge success - e.g. 12 days F7/8 in the Atlantic with a fishing net around the main rudder - and not having to generate 200 AH per day to run it!

OK, we do mostly tradewind sailing these days, but I do wish I'd bought a Hydrovane 20 years ago (I've owned the boat since 1999).

FWIW the Hydrovane people said that they thought we were a bit too big for one. We've no connectiont to the Hydrovane company.

[Michael Cobbe]

Long distance sailing, 10,000 nms, the most common windvane I saw was a Hydrovane and I have seen one a a 50 foot yacht. The smallest yacht was 32 foot and it had a smaller vane.

[gbowen]

I used an RVG type on my 19 ton boat. I selected it because I could build it myself and it could serve as a spare rudder if required. I was thrilled at its performance. I came into Honolulu from Pago Pago with 35 ft following seas following Hurricane Gilma. I feared the wind vane might not cope with the shadowing effect of the waves. Thankfully, it did fine.

Never had an autopilot. I was just a poor man who wanted to go sailing. We were 52 ft overall with a long keel.

[Windpilot]

Without knowing the exact boat and it's design/steering this cannot be answered.
Servo assisted auxilluary rudders have been used successfully on plenty of 50' + sailboats.
Best to ask the individual worldwide popular manufactures of vanes, and look at their similar installations.
They mostly all can accept powered autopilot course input directing a servo pendulum to power the steering input.

[Noisykate]

Another vote for a hydrovane...
Our boat is 42', about 15t.
We found the key to getting it to work effectively is to get the boat 'balanced' first - easier on a ketch, I guess! -
If you are having to work hard on the wheel to keep it on course, the relatively small rudder on the hydrovane will not cope.
Once it is happy, it will go for days with no adjustment.
Our biggest problems on two Atlantic crossings were (a) sargasso weed and (b) getting crew to leave it alone - the course adjustment string is utterly irresistible!

[KP44]

Originally Posted by Vespy

Hey,

I'm a newbie on these forums, and yes, I've searched.

Is there a point in size and weight where a wind vane is no longer productive?

is there any point to using wind vanes on ships above 20t and 50ft?

.

The Monitor Windvane has an excellent record of steering small to very large vessels. During the round-the-world single-hand races, the Monitor was the only windvane used and it was on every boat. I think these were 60' vessels.

My Monitor easily handles our 16 ton, 45' cutter. A small tiller autopilot can be used in place of the wind paddle (sensor) to steer a magnetic course. All steering is powered by the water, which makes it very powerful and capable. I suggest talking to Scanmar International if you want more information.

[AiniA]

A couple of thoughts, there are two main types of vanes (and some minor ones). An auxiliary rudder one like Hydrovane actually steers the boat so there is an upper limit. The Hydrovane people said they thought it would steer our 45' 20 ton boat. 'Thought' did not impress me much. A servo-pendulum type like Monitor only 'steers' the wheel or tiller so has much lighter duty. Any vane requires that you can balance the sails you have up really well.

[barnakiel]

Is there a point in size and weight where a wind vane is no longer productive?

YES

Can a wind vane and an autopilot work together on a large boat? (leave the autopilot a wide target variance, let the vane do most of the work?)

YES. Provided the windvane is of the independent rudder style (the vane driving its own rudder, not the boat's rudder). Examples: Hydrovane, and the biggest WindPilots.


Or is it ultimately just another complication that you need to worry about, which grants little to no benefit on larger boats?

Windvanes are not much more complex than APs. They are a complication, but they may be, in some cases, a necessary one. A marine toilet is a complication too and some boats do not have them. Also a diesel auxiliary is a complication.

And ultimately, to sum up the 3 questions above, is there any point to using wind vanes on ships above 20t and 50ft?

Bigger boats require bigger vanes. At a point the vane becomes impractical.


Boats like e.g. 50' Benneteau Sense are easily driven with e.g. Hydrovane windvanes.

Very fast racy boats do not use windvanes. They use APs. Also small racing boat (Minis) use APs, not windvanes. Also few cats use windvanes.



Cheers,
b.

[Windpilot]

[QUOTE=KP44;3214561]The Monitor Windvane has an excellent record of steering small to very large vessels. During the round-the-world single-hand races, the Monitor was the only windvane used and it was on every boat. I think these were 60' vessels.

Actually I believe you are talking about the Golden globe singlehand races. Vintage boats, the largest was 36' if not mistaken and they did all have windvanes because electric autopilot were not allowed. It was a mix of various windvane makes however monitors were prominent. The much larger Vendee race boats are too fast for windvanes.

[barnakiel]

[QUOTE=Windpilot;3214624]

Originally Posted by KP44

The Monitor Windvane has an excellent record of steering small to very large vessels. During the round-the-world single-hand races, the Monitor was the only windvane used and it was on every boat. I think these were 60' vessels.

Actually I believe you are talking about the Golden globe singlehand races. Vintage boats, the largest was 36' if not mistaken and they did all have windvanes because electric autopilot were not allowed. It was a mix of various windvane makes however monitors were prominent. The much larger Vendee race boats are too fast for windvanes.

Unlikely the Golden Globe as there I think it were not just Monitors. Or at least the winner seemed to have something like a Hydrovane.


Maybe that poster will come back and expand on the thought.



b.

[Windpilot]

Can a wind vane and an autopilot work together on a large boat? (leave the autopilot a wide target variance, let the vane do most of the work?)

YES. Provided the windvane is of the independent rudder style (the vane driving its own rudder, not the boat's rudder). Examples: Hydrovane, and the biggest WindPilots.

ALL SERVO PENDULUM UNITS CAN USE AN ELECTRIC PILOT TO STEER EITHER THE BOATS RUDDER OR ITS OWN AUXILIARY RUDDER. IT DOES NOT MATTER. HYDROVANE ONLY THE RUDDER.


Bigger boats require bigger vanes. At a point the vane becomes impractical.

THE VANE ITSELF ONLY SENSES WIND DIRECTION, LARGER WOULD NOT MATTER AT ALL ON ANY SERVO PENDULUM ( monitor, Cape horn, Windpilot etc), HYDROVANE THE EXCEPTION, IT MOVES THE RUDDER ITSELF ONLY?
AUXILIARY RUDDERS/SHAFT/MOUNTING NEED TO BE EXTREMELY ROBUST ON THESE LARGER VESSELS AND NEEDS SERIOUS CONSIDERA

Very fast racy boats do not use windvanes. They use APs. Also small racing boat (Minis) use APs, not windvanes. Also few cats use windvanes.


ITS ALL ABOUT APPARENT WIND ANGLE. SPEED UP, SLOW DOWN, FAST BOAT, OVERPOWERED THATS NOT GOING TO WORK.
WHAT WORKS BEST TENDS TO BE A SLOW BOAT LOTS OF CONSTANT ANGLED WIND.


WE HAVEN'T EVEN TOUCHED THE SUBJECT OF APPLYING ANY OF THIS TO A HYDRAULIC STEERED LARGER BOAT, MOST HAVE BLEED DOWN MEANING A LOCKED WHEEL TAKING UP SOME USUAL WEATHER HELM WILL BLEED TO NEUTRAL. NOW YOUR AUXILIARY RUDDER WILL NEED TO TAKE THIS UP REDUCING ITS GENERAL EFFECTIVE RANGE.


Cheers,
b.[/QUOTE]