Wind/weather and performance(FF)

I have noticed on my multilevel floating condo complete with oxygen tent above, that going against a good breeze along with it's associated chop(bay sea state) can cost me up to 2 knots. I went out yesterday and was traveling against wind and chop but WITH the tide and was doing 17kts(SOG) at my normal power setting. I made a 180 without touching the power and cruised back in at 19kts!!! I have always noticed quite a difference in speed at the same power setting but didn't think too much of it and probably wrote it off as a tidal thing. But I have recently realized this to be the case. My full enclosure(FF calls it the oxygen tent...and I always get a kick out of it) causes some pretty significant drag....sail area.

Willy has a reasonably low amount of air drag and it shows. I've never increased power w my 40hp engine to compensate for head wind. The "oxygen tent" types may be a bit different but I suspect most all loss of speed is caused by tide flow.

When the wind gets up to 40 or so w 7' seas I always slow down because of the seas and always maintain plenty of headway. So w a low windage boat this is absolutely not a problem.

Baker said:

I have noticed on my multilevel floating condo complete with oxygen tent above, that going against a good breeze along with it's associated chop(bay sea state) can cost me up to 2 knots. I went out yesterday and was traveling against wind and chop but WITH the tide and was doing 17kts(SOG) at my normal power setting. I made a 180 without touching the power and cruised back in at 19kts!!! I have always noticed quite a difference in speed at the same power setting but didn't think too much of it and probably wrote it off as a tidal thing. But I have recently realized this to be the case. My full enclosure(FF calls it the oxygen tent...and I always get a kick out of it) causes some pretty significant drag....sail area.

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not sure if I'm being to nitpicky...but if you notice a 2 knot difference...could there be a 1 knot penalty and a 1 knot gain (like cruising into/with a current?

don't get me wrong...my sportfish definitely had a wind penalty with the hardtop/enclosure...

may want to recheck on a windless/currentless day for a more accurate measure if you care...it's not like you are really gonna change much as the enclosure is nice and your speed at that point won't make a huge difference except maybe for planning or trying to make a destination with low fuel.

when the REAL penalties and wind resistance shows up in ALL boats except subs.....is when you are probably slowing down for chop anyway.

A two-knot difference seems too large. Agree with psneeld that water current could be a factor if measuring speed over ground. Haven't noticed a drop in the Coot's speed with strong headwinds. Perhaps it helps to have a slow, low-profile boat to begin with. Do notice a list, however, with strong beam winds.

Oh yeah baby..an enclosure can definitely slow you down 2 knots at high wind and boat speeds...did on my sportfish...

I was just curious about going with/against the wind...whether all penalty or half penalty and half assist.

Sure current is an issue but I'm hoping that issue was already though of.

Boat's like Coot and Willy will probably only see a major wind penalty when it's so strong that the waves are slowing you down even more..

Magic has a big enclosure. Worth every knot it may steal. We are headed south and some mornings have been real cold. Once the sun is up I am in tee shirt and shorts while others without enclosures are in winter coats, scarves, hats and gloves; I'm dead serious. They look sooo cold. And, when it blows hard or rains, I'm snug as the proverbial bug in a rug. To my mind, it's "knot" even worth thinking about.

Tides and current will effect you. You would be surprised how it even effects you out in open water. I have a full displacement hull with 8.5 kt hull design. When traveling in the Gulf of Mexico I have experienced at 1-2 kt difference depending on head winds and bow seas. I am also starting to understand the currents out there to help me.

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Hot - flybridge under bimini or no bimini (no enclosure)
Cold - lower station with bus/diesel heater on

Comfy from NJ to Florida in December....

best part...no $10,000 worth of canvas and vinyl to worry about or keep clean or struggle with zippers as the warmth of day changes...

psneeld said:

Hot - flybridge under bimini or no bimini (no enclosure)
Cold - lower station with bus/diesel heater on

Comfy from NJ to Florida in December....

best part...no $10,000 worth of canvas and vinyl to worry about or keep clean or struggle with zippers as the warmth of day changes...

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Hmm, your boat photo sure looks like it has an enclosure.

hmason said:

Hmm, your boat photo sure looks like it has an enclosure.

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old pic...it was the first thing I trashed...I have also replaces the flybridge privacy curtains with black ABS ...

I HATE canvas....way too expensive, even if you do your own...and I hate worrying about it flapping a bit in a breeze and tearing seams.

Here a month old pic.

psneeld said:

old pic...it was the first thing I trashed...I have also replaces the flybridge privacy curtains with black ABS ...

I HATE canvas....way too expensive, even if you do your own...and I hate worrying about it flapping a bit in a breeze and tearing seams.

Here a month old pic.

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Our enclosure is made of a material called Stamoid. A tad more expensive than Sunbrella but should last way longer. It is a vinyl type material that hoses right off, won't get moldy or deteriorate. It is double stitched with Goretex. The windows are Strataglass Low E that block UV and have a very slight tint. All zippers are heavy duty nylon, also double stitched with Goretex. It is now at the end of its first year and looks like the day it was installed. I hope I can say the same 5-years from now. Our FB is quite large, and surprisingly, the entire job came in under $8K. The FB does not get a drop of water even in a wind driven downpour. It's almost hard for me to believe.

We are liveaboards and the ability to sit and relax on the FB on a chilly or windy day is like having an extra room.

BTW, on our prior boat, a Grand Banks 36 with a bimini only, I hated snapping on the FB cover only to take it off and fold it up the next morning. The windows on the enclosure are a lot easier. Again, different strokes as they say.

There's a reason there are so many canvas people out there....wherever I can replace it or avoid it....I will...

having run hundreds of boats, maybe thousands, as a pro skipper...no canvas for me....new materials or not.

Don't need any canvas (unless you count the sails and dinghy cover.)

markpierce said:

Don't need any canvas (unless you count the sails and dinghy cover.)

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Mark - That is obviously your favorite pict!! :lol::lol:

The horsepower required to overcome air resistance is the speed in miles per hour, cubed, times the frontal area in square feet divided by 150,000
Where:

IN FL the noisemaker is usually on to power the air cond. in the sealed Oxygen tent.

Boating in canned air , a new way to enjoy the day!

Art said:

Mark - That is obviously your favorite pict!!

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http://epapers.bham.ac.uk/1723/1/2013-03_D_Houghton.pdf

RickB said:

http://epapers.bham.ac.uk/1723/1/2013-03_D_Houghton.pdf

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Rick - Interesting, Thanks! - Art

And where does this leave us re Mark's favorite picture?? LOL

An Excerpt from link you provided:

"Within the multi-dimensions of disclosure, it has been argued that there are two distinct properties, or continuums: breadth and depth (Collins & Miller, 1994; Joinson, 2001; Moon, 2000; Spiekermann, Grossklags, & Berendt, 2001; Tidwell & Walther, 2002). Breadth relates to the quantity of information disclosed (both frequency and category), and depth to the quality. Depth can range from surface information, such as demographic data, to more core values, such as sexual fantasies and desires (Altman & Taylor, 1973; Joinson & Paine, 2007). Choosing to disclose different information of varying depth and breadth is based on a number of factors including the environment or situation in which the individual finds themselves and their own personal characteristics."

Rick needs to add in all the small stuff , masts , a fence around the deck, dink hanging .

It's all part of the frontal area. Those who are interested can calculate that area and add it to the total.

psneeld said:

I HATE canvas....

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I DESPISE canvas...including on other peoples boats. As summer live aboards, we make a point of keeping our sundeck and fly bridge open to the beautiful summer weather (hardtop and bimini only). When boats that are fully enclosed with canvas occupy transient slips in the immediate area, the outdoor views are spoiled...welcome to life in the canvas canyon. Ban canvas side enclosures between May and September north of the Mason Dixon line!

My preferred extent of canvas...

Would be a real bitch of a job to drop full enclosure for getting into our covered slip... hving that much canvas! Time to erect enclosure again for each cruise would wear us out!

That said - I appreciate other's wishes to have full enclosure. Heck... there are some locations in PNW as well as New England and Canada where if I resided I too might have full enclosure. But it's not needed in SF Delta!

psneeld said:

There's a reason there are so many canvas people out there....wherever I can replace it or avoid it....I will...

having run hundreds of boats, maybe thousands, as a pro skipper...no canvas for me....new materials or not.

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There are lots of mechanics, riggers, electronics guys, and delivery captains out there as well. I would not throw away my engines!

I'm curious as to what you use to protect your flybridge from rain/sun damage etc. Do you leave it open to the elements 24/7 ? Do you still have your weather cloths or have you removed them as well? Not to beat a dead horse here , but FYI, I have been a boat owner for 51 years, have a Captain's license, and now liveaboard boat #8. I've had enclosures, no enclosures, dodgers and no dodgers, (including the Dodgers that left Brooklyn for LA and that still tics me off) and for me, having an enclosure is to us one of the best investments one can make on a liveaboard boat. That's just the way it looks from here. Howard

I somewhat agree ref the need(or lack thereof) for full enclosure if you have a lower helm. But I can certainly understand if you are a liveaboard how it can be another living space. Also, it sure is nice in the Winter when you are "outside" cooking like it is in a greenhouse and you are comfy warm when it is windy and cold out.

And back to my point, I do realize the effects of tide as i mentioned it in my original post. This wasn't a tidal thing. If anything, the tide should have been helping me going to weather. Anyway, I just thought it was interesting that the "oxygen tent" has that much effect on drag at planing speeds.

hmason said:

There are lots of mechanics, riggers, electronics guys, and delivery captains out there as well. I would not throw away my engines!

I'm curious as to what you use to protect your flybridge from rain/sun damage etc. Do you leave it open to the elements 24/7 ? Do you still have your weather cloths or have you removed them as well? Not to beat a dead horse here , but FYI, I have been a boat owner for 51 years, have a Captain's license, and now liveaboard boat #8. I've had enclosures, no enclosures, dodgers and no dodgers, (including the Dodgers that left Brooklyn for LA and that still tics me off) and for me, having an enclosure is to us one of the best investments one can make on a liveaboard boat. That's just the way it looks from here. Howard

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No dead horse unless you think everyone has to listen to your opinion only..some of us are still nicely discussing the merits.

I don't use anything as there's nothing up there to really protect...a couple folding chairs with covers on them...a few other things....but I would at MOST have a mooring cover if I thought anything needed to be protected beyond it's individual cover.

I am on my 3rd liveaboard and have never been so happy as to minimize my canvas "exposure". On my sportfish I canned the bimini as soon as I got the boat and put a hardtop on it. It's just my opinion but generally in my experience...canvas is a high priced, short lived, high maintenance item for what it is. If I want my flybridge enclosed for more living space....I'll enclose it with anything under the sun but canvas and vinyl.

The new siff tops that snap/bolt right on to a bimini frame are but one of many examples of better materials coming out to replace "canvas".

I'm not "right"...just tired of canvas and canvas fixers/makers/maintenance/worrying about wind....

Art said:

Mark - That is obviously your favorite pict!! :lol::lol:

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It is for threads concerning flying bridges.

psneeld said:

It's just my opinion but generally in my experience...canvas is a high priced, short lived, high maintenance item for what it is.

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I agree with the above and it has been a requirement to "not have a canvas encloser" on my boat. The small cockpit awning I have is quite enough. That said, however, I can see why those with fly bridges do enclose them with canvas and vinyl or strataglass.

Our choice so far has been to unfold a 10x10 yard structure , $65 at the local store and it has gone years in salt water.

Sure our cockpit is unusual in being able to eat a 10x10 item ,but it works for us and cost less than the sales tax of a unit that can be foulded but not simply foulded and stored.