Cruisers Forum
 


Reply
  This discussion is proudly sponsored by:
Please support our sponsors and let them know you heard about their products on Cruisers Forums. Advertise Here
 
Thread Tools Search this Thread Rate Thread Display Modes
Old 13-09-2021, 12:04   #106
Registered User

Join Date: Jun 2012
Location: Port Aransas, Texas
Boat: 2019 Seawind 1160 Lite
Posts: 2,126
Re: Wind Instrument

Quote:
Originally Posted by s/v Jedi View Post
For wind sensor data, I believe racers use a wind sensor in front of the bow for upwind sailing instead of at the top of the mast. They mount it to the pulpit.
Have never seen a wind transducer mounted on the bow. And have been involved in a lot of big boat racing - albeit mostly multihulls - as well as race boat setups.
sailjumanji is offline   Reply With Quote
Old 13-09-2021, 12:16   #107
Registered User

Join Date: Jun 2012
Location: Port Aransas, Texas
Boat: 2019 Seawind 1160 Lite
Posts: 2,126
Re: Wind Instrument

Quote:
Originally Posted by s/v Jedi View Post
Here, just in case a pictureto make things clear: wind sensor, mounted at and forward of the bow.
Your example is a foiling Americas Cup boat, where wind angle is always coming from forward.

For the rest of us (i.e., with boats that don't sail with no hull in the water), boats also race downwind. A bow mounted wind transducer gives zero reliable information then, as it would either be behind the sail or being affected by flow over sail(s).
sailjumanji is offline   Reply With Quote
Old 13-09-2021, 14:00   #108
always in motion is the future
 
s/v Jedi's Avatar

Cruisers Forum Supporter

Join Date: Feb 2009
Location: in paradise
Boat: Sundeer 64
Posts: 18,757
Re: Wind Instrument

Quote:
Originally Posted by wingssail View Post
Jedi, I was asking if you are aware of a trend towards this, I am not.
I first started seeing this with racers 8 or 10 years ago. Then cruisers followed because it works so well… I’d call that a trend but of course many/most on the forum don’t even believe this is done even after posting pics so I guess it’s not for everyone
__________________
“It’s a trap!” - Admiral Ackbar.

s/v Jedi is offline   Reply With Quote
Old 13-09-2021, 14:32   #109
Registered User

Join Date: Mar 2016
Location: San Francisco
Boat: Morgan 382
Posts: 2,839
Re: Wind Instrument

Quote:
Originally Posted by s/v Jedi View Post
You mean cruising monohulls?
Interesting. There can be quite a gradient in wind speed between the surface of the water and the top of the mast, so I would expect a sensor to read a bit slow compared to the masthead. I expect that this would also shift the apparent wind direction aft compared to the masthead.

But probably more importantly, it won't be subject to the motion of the mast, and would read a much better and stable wind direction. No up wash from the sail, either.
__________________
-Warren
wholybee is offline   Reply With Quote
Old 13-09-2021, 15:22   #110
Registered User

Join Date: Oct 2019
Location: Kennebunk ME
Boat: Owner built 60’ Aluminum Expedition Yacht.
Posts: 1,854
Re: Wind Instrument

I’m sorry you had a bad trip. It’s a horror to loose your compass light and not being able to get some flashlight quickly.
I don’t have an electrical system with bells and whistles. No masthead stuff except a tricolor and a strobe. I learned to sail without it. Here is why.
A long time ago an Eastern Airlines flight crashed into the Everglades and a lot of people were killed. Two pilots and an engineer and another pilot getting a ride in the cockpit. They were all focused on a gear not down light. Nobody was watching the altimeter and they flew the plane into the swamp.
I think there is way too much focus on electrically powered “stuff” and it’s easy to forget or grow rusty with basic skills.
I’m not going to junk my AIS or my autopilot but information overload to the brain is a danger. Keeping it simple is one way.
From what you’ve posted, your boat and where you sail, I’d venture to say you are one heck of a skipper. I’m going to keep a small led flashlight next to the helm now. Everybody learns from scary days at sea.
I guess I’m getting too old to drive my boat with a mouse and a smart phone.
Happy trails to you.
Captain Mark who is busy helping his manatee crew with their ORCA costumes for Halloween. Good grief what a crew
Manateeman is offline   Reply With Quote
Old 13-09-2021, 17:11   #111
Registered User

Join Date: Apr 2007
Location: Australia
Boat: Island Packet 40
Posts: 6,415
Images: 7
Re: Wind Instrument

Quote:
Originally Posted by Manateeman View Post
I’m sorry you had a bad trip. It’s a horror to loose your compass light and not being able to get some flashlight quickly.
I don’t have an electrical system with bells and whistles. No masthead stuff except a tricolor and a strobe. I learned to sail without it. Here is why.
A long time ago an Eastern Airlines flight crashed into the Everglades and a lot of people were killed. Two pilots and an engineer and another pilot getting a ride in the cockpit. They were all focused on a gear not down light. Nobody was watching the altimeter and they flew the plane into the swamp.
I think there is way too much focus on electrically powered “stuff” and it’s easy to forget or grow rusty with basic skills.
I’m not going to junk my AIS or my autopilot but information overload to the brain is a danger. Keeping it simple is one way.
From what you’ve posted, your boat and where you sail, I’d venture to say you are one heck of a skipper. I’m going to keep a small led flashlight next to the helm now. Everybody learns from scary days at sea.
I guess I’m getting too old to drive my boat with a mouse and a smart phone.
Happy trails to you.
Captain Mark who is busy helping his manatee crew with their ORCA costumes for Halloween. Good grief what a crew
My mobile phone has GPS, a compass and navionics in it. I keep it in a ziplok bag to keep it dry. I also have a waterproof tablet with Navionics and another with openCPN in it which I could put in a ziplok bag. Lots of gadgets available these days for backup for the primary system.
__________________
Satiriker ist verboten, la conformité est obligatoire
RaymondR is offline   Reply With Quote
Old 13-09-2021, 18:13   #112
Registered User
 
lateral's Avatar

Join Date: Apr 2011
Location: NZ
Boat: S34 Bob Stewart - 1959 Patiki class. Re--built by me & good mate.
Posts: 1,109
Re: Wind Instrument

Drifting off DH's quest for accurate true wind, but reminded of what can happen if you lose your network and hence AP, I can't imagine the complexity of getting your cell ph/waterproof tablet to drive AP, and stay powered up. Do-able I guess but out of my
imaginings of reasonably KISS. (And diy skill)
I have backup drive unit, APC, compass, but little use in adverse weather situation.
So this thread is a timely reminder to establish a switch over, mini N2K network for AP.
(No wind mode) Primarily for single handing.
The holy grail of true wind is not something I have time for. Just as long as it appears about right is good enough. Otherwise its on ignore.
lateral is offline   Reply With Quote
Old 13-09-2021, 21:52   #113
Registered User

Join Date: Apr 2007
Location: Australia
Boat: Island Packet 40
Posts: 6,415
Images: 7
Re: Wind Instrument

Quote:
Originally Posted by lateral View Post
Drifting off DH's quest for accurate true wind, but reminded of what can happen if you lose your network and hence AP, I can't imagine the complexity of getting your cell ph/waterproof tablet to drive AP, and stay powered up. Do-able I guess but out of my
imaginings of reasonably KISS. (And diy skill)
I have backup drive unit, APC, compass, but little use in adverse weather situation.
So this thread is a timely reminder to establish a switch over, mini N2K network for AP.
(No wind mode) Primarily for single handing.
The holy grail of true wind is not something I have time for. Just as long as it appears about right is good enough. Otherwise its on ignore.
In a contingency such as that which the OP experienced I'd be happy to have an autopilot which could hold a course, and know where I was and what direction I was heading in.

Whilst reading some of the posts herein I slipped into recall on how we used to do things before we had all this wonderful instrumentation. One of the incidents I can recall was sailing up a depth contour during a pitch dark, rainy night to make it through a fairly narrow pass between a point and an offshore reef. Nerve wracking in those days but one would not think twice about it with modern instrumentation (I very badly needed to get into a calm anchorage as I had a passenger who was driving be nuts and roadstead anchoring was not an option)
__________________
Satiriker ist verboten, la conformité est obligatoire
RaymondR is offline   Reply With Quote
Old 14-09-2021, 01:22   #114
Registered User

Join Date: May 2014
Boat: Shuttleworth Advantage
Posts: 2,241
Images: 2
Re: Wind Instrument

Quote:
Originally Posted by lateral View Post
Drifting off DH's quest for accurate true wind, but reminded of what can happen if you lose your network and hence AP, I can't imagine the complexity of getting your cell ph/waterproof tablet to drive AP, and stay powered up. Do-able I guess but out of my
imaginings of reasonably KISS. (And diy skill)
I have backup drive unit, APC, compass, but little use in adverse weather situation.
So this thread is a timely reminder to establish a switch over, mini N2K network for AP.
(No wind mode) Primarily for single handing.
The holy grail of true wind is not something I have time for. Just as long as it appears about right is good enough. Otherwise its on ignore.
Totally agree.

We seem to have lost sight of our objective.

With all these highly accurate wind sensors none compensate for the effect of heel angle on the measured apparent wind angle.

Assuming a mono sailing hard on the wind heels 20-25 degrees then the measured apparent wind angle would vary by up to 10% from the plane of the wind. Add on the calculations to obtain True Wind angle without taking into account leeway, drift and wave action and you always have a wholly in-accurate result.

The accuracy of a wind instrument is therefore relative to the boat and useful only in optimising the performance of "that" particular boat in those particular, largely unrepeatable, conditions.

Far better to have a sensor that gives a stable reading with minimum damping that provides a relatively constant, if inaccurate, input to your computations.

Given modern GPS, VMG to destination is a much better guide to performance, everything else is nice to have but secondary to the primary objective.
Tupaia is offline   Reply With Quote
Old 14-09-2021, 04:57   #115
Registered User

Join Date: Mar 2016
Location: San Francisco
Boat: Morgan 382
Posts: 2,839
Re: Wind Instrument

Quote:
Originally Posted by Tupaia View Post
Totally agree.

We seem to have lost sight of our objective.

With all these highly accurate wind sensors none compensate for the effect of heel angle on the measured apparent wind angle.

Assuming a mono sailing hard on the wind heels 20-25 degrees then the measured apparent wind angle would vary by up to 10% from the plane of the wind. Add on the calculations to obtain True Wind angle without taking into account leeway, drift and wave action and you always have a wholly in-accurate result.

The accuracy of a wind instrument is therefore relative to the boat and useful only in optimising the performance of "that" particular boat in those particular, largely unrepeatable, conditions.

Far better to have a sensor that gives a stable reading with minimum damping that provides a relatively constant, if inaccurate, input to your computations.

Given modern GPS, VMG to destination is a much better guide to performance, everything else is nice to have but secondary to the primary objective.
Probably the closest:
https://www.bandg.com/bg/series/h5000/

Quote:
Wind measurement is affected by the wind induced at the top of the mast by the pitching and rolling of the yacht. The solution is 3D motion correction. H5000 takes data from multiple sensors including high-specification rate-gyros to correct for induced wind, providing the best wind solution available in an instrument system.
I think it is a very narrow use case that requires correction of heal angle to apparent wind direction. What really matters is repeatability. Build your polars to measurements taken on your boat, and as long as it is repeatable, that is what really matters.

Otherwise, you are going down a rabbit hole. Higher windspeed at the mast creates a different apparent wind angle than on deck. The reported windspeed on gribs is at a different height then the top of your mast, also affecting AWA, and there is significant up wash from the sails, and motion of the boat induces error.

I don't think there is a simple fix for all of that, but a complex computer can do it. But the use case is small.

If you are good at math/trig, you could try using the NEMA converter plugin in opencpn to make the calculations. But, the data sample rate might be too slow to produce acceptable results. Analog instruments into a computer with a high sample rate would produce the best results.
__________________
-Warren
wholybee is offline   Reply With Quote
Old 14-09-2021, 06:40   #116
Registered User

Join Date: Oct 2019
Location: Kennebunk ME
Boat: Owner built 60’ Aluminum Expedition Yacht.
Posts: 1,854
Re: Wind Instrument

I went back to the original post. Maybe I got this wrong, please correct.
Dark and stormy night...we’ve all been there...Crew sleeping. Rough seas.
GALE. Hard on the wind. Heading on plotter wrong. Can’t see compass. Unplanned gyre. Injury to hand.
I’m NOT going to Monday morning quarterback. Obviously, he’s a very skilled skipper. Everybody who has any real time offshore will re-think (to themselves)
each and every decision afterwards.
The point in my post was this...something fails in your complex electronic world, forget about it. Go back to basic sailing. Rely on the sailing skills you learned when you began sailing. People sailed for centuries without smart devices and there is a real danger in being too dependent upon them. That was the lesson in the Eastern Airline crash.
If my system crashed (we don’t have one) I wouldn’t be trying to replace it with a cell phone. Complex electronics fail. I can see the logic in having a backup system. I hope you can see my point in stressing the need to practice sailing without the support of electronics.
There is case after case of collisions, groundings and other mishaps directly attributed to misinterpreted information or electronic system failures.
Stuff..engines, running rigging, anchors...all seem to fail at the worse possible time. It’s good practice to pretend the stuff just failed and it keeps the best computer on the boat running on the latest software. Your brain.
Happy trails to you.
Captain Mark
Manateeman is offline   Reply With Quote
Old 14-09-2021, 06:58   #117
Moderator
 
Dockhead's Avatar

Cruisers Forum Supporter

Join Date: Mar 2009
Location: Denmark (Winter), Helsinki (Summer); Cruising the Baltic Sea this year!
Boat: Cutter-Rigged Moody 54
Posts: 33,750
Re: Wind Instrument

Quote:
Originally Posted by Manateeman View Post
I went back to the original post. Maybe I got this wrong, please correct.
Dark and stormy night...we’ve all been there...Crew sleeping. Rough seas.
GALE. Hard on the wind. Heading on plotter wrong. Can’t see compass. Unplanned gyre. Injury to hand.
I’m NOT going to Monday morning quarterback. Obviously, he’s a very skilled skipper. Everybody who has any real time offshore will re-think (to themselves)
each and every decision afterwards.
The point in my post was this...something fails in your complex electronic world, forget about it. Go back to basic sailing. Rely on the sailing skills you learned when you began sailing. People sailed for centuries without smart devices and there is a real danger in being too dependent upon them. That was the lesson in the Eastern Airline crash.
If my system crashed (we don’t have one) I wouldn’t be trying to replace it with a cell phone. Complex electronics fail. I can see the logic in having a backup system. I hope you can see my point in stressing the need to practice sailing without the support of electronics.
There is case after case of collisions, groundings and other mishaps directly attributed to misinterpreted information or electronic system failures.
Stuff..engines, running rigging, anchors...all seem to fail at the worse possible time. It’s good practice to pretend the stuff just failed and it keeps the best computer on the boat running on the latest software. Your brain.
Happy trails to you.
Captain Mark

I agree with this.


My primary sin was not fixing the compass light.


I will do that very first thing when I'm back on the boat.
__________________
"You sea! I resign myself to you also . . . . I guess what you mean,
I behold from the beach your crooked inviting fingers,
I believe you refuse to go back without feeling of me;
We must have a turn together . . . . I undress . . . . hurry me out of sight of the land,
Cushion me soft . . . . rock me in billowy drowse,
Dash me with amorous wet . . . . I can repay you."
Walt Whitman
Dockhead is offline   Reply With Quote
Old 14-09-2021, 07:31   #118
Moderator
 
Dockhead's Avatar

Cruisers Forum Supporter

Join Date: Mar 2009
Location: Denmark (Winter), Helsinki (Summer); Cruising the Baltic Sea this year!
Boat: Cutter-Rigged Moody 54
Posts: 33,750
Re: Wind Instrument

Quote:
Originally Posted by wholybee View Post
Probably the closest:
https://www.bandg.com/bg/series/h5000/

I think it is a very narrow use case that requires correction of heal angle to apparent wind direction. What really matters is repeatability. Build your polars to measurements taken on your boat, and as long as it is repeatable, that is what really matters.

Otherwise, you are going down a rabbit hole. Higher windspeed at the mast creates a different apparent wind angle than on deck. The reported windspeed on gribs is at a different height then the top of your mast, also affecting AWA, and there is significant up wash from the sails, and motion of the boat induces error.

I don't think there is a simple fix for all of that, but a complex computer can do it. But the use case is small.

If you are good at math/trig, you could try using the NEMA converter plugin in opencpn to make the calculations. But, the data sample rate might be too slow to produce acceptable results. Analog instruments into a computer with a high sample rate would produce the best results.

I agree with this, and the previous post.


It's a lot more complex than I imagined when I first started this.


So -- is it a fool's errand? Or not?


It seems like the H5000 is the gold standard for this, which can very well deal with the B&G MHU's which have spent years in wind tunnels.


I am however attracted to the CV7 which is less sensitive to heel and doesn't have any mechanical inertia issues to correct.


What about Sailmon? Or Occam?
__________________
"You sea! I resign myself to you also . . . . I guess what you mean,
I behold from the beach your crooked inviting fingers,
I believe you refuse to go back without feeling of me;
We must have a turn together . . . . I undress . . . . hurry me out of sight of the land,
Cushion me soft . . . . rock me in billowy drowse,
Dash me with amorous wet . . . . I can repay you."
Walt Whitman
Dockhead is offline   Reply With Quote
Old 14-09-2021, 08:34   #119
Registered User
 
wingssail's Avatar

Join Date: Jan 2010
Location: On Vessel WINGS, wherever there's an ocean, currently in Mexico
Boat: Serendipity 43
Posts: 5,508
Send a message via AIM to wingssail Send a message via Skype™ to wingssail
Re: Wind Instrument

Quote:
Originally Posted by Dockhead View Post
...I am however attracted to the CV7 which is less sensitive to heel and doesn't have any mechanical inertia issues to correct...
Why would CV7 be less sensitive to heel? It is my thought that the apparent wind angle at the sensor actually does change when the boat heels and any sensor, regardless of how it measures that angle, will experience the same change, which will affect the accuracy of the true wind calculation.

But anyhow, the adjustment for angle of heel is calculated in the display system in H5000. It would not matter which sensor is feeding the raw data.

The real question is, how important is that adjustment anyhow?
__________________
These lines upon my face tell you the story of who I am but these stories don't mean anything
when you've got no one to tell them to Fred Roswold Wings https://wingssail.blogspot.com/
wingssail is offline   Reply With Quote
Old 14-09-2021, 08:45   #120
Registered User
 
wingssail's Avatar

Join Date: Jan 2010
Location: On Vessel WINGS, wherever there's an ocean, currently in Mexico
Boat: Serendipity 43
Posts: 5,508
Send a message via AIM to wingssail Send a message via Skype™ to wingssail
Re: Wind Instrument

Quote:
Originally Posted by Manateeman View Post
...It’s good practice to pretend the stuff just failed and it keeps the best computer on the boat running on the latest software. Your brain...
We don't have to pretend. The stuff does fail often enough to give us plenty of practice.
(I was sitting below decks on Bumblee V the night before Sydney Hobart start with a few other navigators. We were trading drivers for the instrument systems. Some mates were also present who were bored with the process and wanted to get off to the bar. One forward hand asked rhetorically, "What difference does it make, it'll all be down an hour after the start anyhow?")
When the instruments are down you automatically switch to other clues about what is going on. This needs to be instinctive.

Always, the focus should be on sailing the vessel, not on repairing instruments or enabling a rarely used back-up system.

When things are stabilized there will be time to get the electronics going again. And on Monday morning you examine ways to prevent reoccurrence.

We can be certain that the OP knows this and his example indicated that he did it in that order. Good seamanship.

The reason for this thread is: Since a failure of the CV7 sensor wiring caused the system outage, and he's considering replacing that device, why not look at alternatives?
__________________
These lines upon my face tell you the story of who I am but these stories don't mean anything
when you've got no one to tell them to Fred Roswold Wings https://wingssail.blogspot.com/
wingssail is offline   Reply With Quote
Reply

Tags
men, rum, wind

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
B&G wind instrument calibration fix for Triton wind jbinbi Marine Electronics 6 19-02-2021 20:33
Tacktick mn30 Wireless Wind Instrument - Wind transmtter details jono63812 Marine Electronics 0 06-07-2016 13:10
Want To Buy: Raymarine ST60 Wind & Close Hauled Wind instrument jphillips48 Classifieds Archive 4 20-09-2013 03:07

Advertise Here


All times are GMT -7. The time now is 21:18.


Google+
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
Social Knowledge Networks
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2024, vBulletin Solutions, Inc.

ShowCase vBulletin Plugins by Drive Thru Online, Inc.