Removable or hinged winglets on sportboats

[Christo Mroz]

Saw a Vivace-like sport boat in the Shilshole dry sail yard. Nebula. Know what it is? S8? Would like to chat with the owner about winglets on sport boats. Or, respond here about whether you think deck winglets like on Vivace, Don't Panic, S8...could help a narrow, overpowered, short handed sport boat upwind.

 

[JulianB]

The reason you use Winglets is legal towing width and parking space width is sort of limited to 2.5m.
If you start from scratch the winglets tend to be lighter, stronger and more aero/hydro "clean".

If you are doing a add-ons then alloy/carbon tubes is simpler and quicker.

Winglets tend to end up about 20kg per side, and you would be hard pressed to get alloy tube under that, you need 70mmOD with a 3mmWT, probably 3 of them at at-least 1m each transverse per side, then for-n-aft beam, often quite large, 80mmOD x 2mmWT to swing off.

Both of those tubes are about 2kgs/m so transverse is going to be 3 x 1m x 2kgs so 6kgs, then the f-n-a at say 4m so another 8kgs, then add inner beam, joints, net and anchors, (in the hull) yad yad yad, you will soon be over 20kgs. Carbon can be more elegant and lighter, but still looking at 16-17kgs.

You need to swing off the end of these, so they need to be able to take 400kgs/m on 2 transverse beams + some safety margin.

First thing to do is work out if a) the rig and b) the hull can take the extra loading.

Then, will the extra width = extra RM outweigh the extra weight.

It's not all sugar and roses!

jB in Switzerland.

 

[neuronz]

Can you give some more detail? Generally I think it could help to make make up for some of the lost righting moment due to being shorthanded. The additional weight might not be a huge issue if you are sailing with reduced crew weight. I used to have a PDF where someone had documented a retrofit similar to what Julian outlined above to a Magic 25 to replace the trapezes. I can try and dig it up for you, but it might take a few days. Adding (temporary) trapezes might actually be a good way to test how much difference wings will make in terms of righting moment.

 

[JulianB]

Can you be more specific with what you want me to elaborate on please. Way to many variables for a open request like that.

jB

 

[neuronz]

@JulianB, I actually meant to ask the original poster to be more specific of his situation. I think you already gave a very detailed summary of a possible retrofit solution.

 

[Christo Mroz]

The FT10 was designed to fit in a container. Once. At the beginning of its life. Very nice boat, but could use some beam. That beam could use some water ballast up wind. Seems like a near perfect boat if it were around 400 mm wider on each side, with water ballast. Vivace style so they fold up or
Dont panic style so they latch off, to still be able to trailer or fit in a container. I'm not worried about handicaps on an older sport boat like this. Nor is the fabrication an issue for me. But I'll understand if you think I need a different boat. Let's call it a thought exercise for now. My most recent winged boat was a Nacra I-20 with folding wings. Oh, I'm probably not going to trapeze off of a FT10 to test out the RM. Neuronz, curious about the magic 25.

 

[JulianB]

Agree the FT10 is very thin, I have sailed one a few times, the FE28R is a much nicer boat.
Hindged Wings on a curved gunwale is impossible, so need to flick that idea.
But Water Balast is a good workable idea. There are pumps that are use in "off-roading" that can move 200-300kgs in 30-40secs and even in SFBay, or Sydney, it's not often that "sports boats" engage in tacking battles so 10-15sec dump and load arrangments are a bit ridiculous.
You will still be carrying 20-30kgs in batteries and pumps and hosing and crap, so need to keep all that in mind.

 

[stealth]

There are a Modified Hobie Magic 25 which has wings as Julian describe above.

 

[FlyingCircus2]

Can you give some more detail? Generally I think it could help to make make up for some of the lost righting moment due to being shorthanded. The additional weight might not be a huge issue if you are sailing with reduced crew weight. I used to have a PDF where someone had documented a retrofit similar to what Julian outlined above to a Magic 25 to replace the trapezes. I can try and dig it up for you, but it might take a few days. Adding (temporary) trapezes might actually be a good way to test how much difference wings will make in terms of righting moment.

If you can find that I'd be very curious about it. I bought a magic 25 last year. I should get it racing this summer,l. Still fixing it up but I can see how wings could be an advantage.

 

[Ex Machina]

If you can find that I'd be very curious about it. I bought a magic 25 last year. I should get it racing this summer,l. Still fixing it up but I can see how wings could be an advantage.

There is a magic 25 thread somewhere with some info on the mods done to that boat , from memory it has some length added to the very short keel and possibly a bulb upgrade from this century

 

[JulianB]

Guys, if you add wings, then you are adding RM.
Lead hanging directly below a hull, dose not matter how long the fin is, there is no additional RM.

So put a fin on which is the right size to carry the expected sideload, and that can be quite small.
Then use Wings or water balsat or crew hicking or a combination of all 3 to generate RM.

Pretty obviously as you increase RM, you increase sideload, but you also increase speed and that a X² law.
Most fins are too big already, so think about the best way to increase RM, and worry about the rest later!

My next fin is likely to be 200mm shorter and the bulb 1/2 the weight!
But I am not expecting any RM from the bulb!

 

[Floating Duck]

whether you think deck winglets like on Vivace, Don't Panic, S8...could help a narrow, overpowered, short handed sport boat upwind.

Well howdy there! I'm the owner of Nebula so i think i can answer this question very very easily...

No. Absolutely not. Wings do NOT help any boat when you "properly" use them.

I.e. IF the aim is to increase RM, then you should add more sail when you add wings. The problem is that then you are back to square one, you will still eventually get overpowered - but now you ALSO have to keep in mind dragging a wing in the water, and having to "hike in" in the lulls so you don't "capsize" to weather.

TLDR, the boat is VERY twitchy, as the RM effectively decreases with heel - which is the opposite of what happens with lead in the bottom. However, yes, wings will help if you DON'T add more SA.

Then use Wings or water balsat or crew hicking or a combination of all 3 to generate RM.

But this is exactly why I got this boat, to eventually build water ballast into the wings. If i wasn't planning on WB, I'd much rather have wing "racks" - preferably some that could be folded prior to docking.

It was mentioned above somewhere, but solid wings like ours are heavy. Plus when anyone gets on the boat at the dock the whole thing heels over 30deg and the wing can clip the dock if you aren't careful.

I LOVE the wings. IMO this is the only proper way to build a sportboat (or with traps, WB, or foils - all do the same thing). They help make the boat really fast, really twitchy, athletic, and hard to sail well. Exactly the kind of challenge that i was looking for.

Feel free to ask me any other questions that you may have. The boat is an absolute blast. Only 1 season with it, much refinement still to come!

 

[huey 2]

What design is Nebula ...looks familiar...like the Duncanson designs in Thailand..?

 

[Floating Duck]

What design is Nebula ...looks familiar...like the Duncanson designs in Thailand..?

Wow you nailed it. Not just "like"... It IS a Duncanson PS8.

One of... 6? Not many made. I don't understand why they didn't make more, it's insanely fun. Wait, i take that back. I DO understand why they didn't make more. It's too extreme of a boat for 90% of sailors out there to be honest.

 

[neuronz]

If you can find that I'd be very curious about it. I bought a magic 25 last year. I should get it racing this summer,l. Still fixing it up but I can see how wings could be an advantage.

Checked two of my old hard drives, but could not find it. There is one old laptop left to check, but I am fairly pessimistic about my chances to find it there.

 

[huey 2]

They were a Kit design by John Duncanson for the longnitudal and athwartship frames to make a Plywood CNC 'Clip Together Jigsaw Eggcrate' former for the layer of stripplank WRC layer that was the laid up with epoxy and cloth inside and out . His Family really helped and the PS8 was born....
There was a 30' full kit boat actually called Jigsaw in Rozelle..with full accommodation built in plus a shoal draft centerboard and dagger rudder...the owner could then dry store on simple slipyard trolley at the end of the day.
There was also a larger 33' winged short handed racer in Qld Flying Dragon ?? with bow prod and for its time a massive asymetric spinnaker?? with C/B and Dagger rudder, and Wings that had Water Ballast.
The name Duncanson has been famous in yachting in Australia'...
But his little Joggie and very famous "Gingerbreadman" was perhaps one of the earliest lightweight 'Ironing board racers' built with WRC strip planking wood composite in Australia.
There was also his JOG style racer RUN ?? Victoria , a mini lightweight giant slayer upwind and downwind speedster...and a variation in Souyh Australia...not sure if ever launched.
Usually people didnt understand how much time and money was saved by having an accurate CNC formwork and how much time and costs you saved, as you didnt have to develop lines from the designers offcets , and then hand cut frames with assembly into a semi accurate mold.
John went to to be one of the early adopters of this this technology....
Unfortunately was the subject of a certain malevolence from others in the market and the industry...not a nice way to retire. He was even trolled in this forum , but as you say the PS8s certainly Put a lot of 'Smiles on Face' Sailing. A revolutionary.

 

[huey 2]

You can search this Forum with the name John Duncanson.

 

[Rantifarian]

.
There was also a larger 33' winged short handed racer in Qld Flying Dragon ?? with bow prod and for its time a massive asymetric spinnaker?? with C/B and Dagger rudder, and Wings that had Water .

Are you referring to one of the various Sayer designs? They are light shorthanded boats with little wings and water ballast.
Rudders have a habit of falling off though

 

[huey 2]

Search this forum for the answer on John Duncanson...dont even try to put in the same camp. .. please. !!
The Qld racer is as I described .

Sayer designed in ferro to WRC
then through to carbon foam He did some Joggies

But between Merv Atkinson [D4 Haminex], Kel Steinman [B52] and John Duncanson ,these designers really changed the look of racing in Australia with the lightweight composite racers. Trailer Sailers and Trimarans through to the mighty 40' Buckle Up . The start of low cost owner builder racers.
There were many other designers but predominately, they were foam core composite designs.

The Crowther 40 Cat, Balena Bullfrog ,...Johnson built in long grain balsa epoxy composite ..cleaning up pretty well everything shorthanded for a long while.
Julian B on this site also built the first long grain balsa epoxy composite 18' skiff.

WEST epoxy was principle in this development starting in NZd with Arnie Duckworth, Rob Denny [Harryproa on this forum] and Graham Bird,.... ATL composites Australia is still run By Arnies Ex in Qld and is the cutting edge of material composite sciences Duracore through to CNC Duflex are key components available today.
NZd had Jim Young Laurie Davidson, Murray Ross, Greg Elliott Kevin Dibley sorry for the ones I missed .
Check out the ebook 'Charge of the LIght Brigade' You can also search for an online version of this book on SA.. the writer is sometimes on this forum. A comprehensive story NZd based.

Sayer did some short handed racer s Bionic Applebox was an early one the only reason it failed in SYD -Aukland was the main bolt rope wasnt specd to mast sailtrack
And some pretty successful Melb - Osaka racers ...One cleaned up a race series, just recently [Victoria?] Ryuyin and Wasabi are two off his designs
He was a hands on designer builder racer originally from NZd....but some of his designs were built by owner builders...Im not privy to said rudder failures but all of us think we know everything but in truth... Reality can be different.
He designed and co built a BOC 50 footer True Blue that took David Adams Single Handed Around the World , winning his class and beating some of the bigger 60s ...huge 'main '...no major dramas , other than foil cavitation in the Southern Ocean.

All of these designs had to be lofted and framed, but there were many inaccuracies in the builds ....it didnt initially matter as they were 'just quick' ....Between JD and ATL , the CNC craft was refined and developed that led to to a higher quality of boat. This also matched the new requirements and regulations in Boatbuilding. Time and Money was the other benefit.
...getting to go Sailing Quicker is the end result.

 

[bushsailor]

yes John Duncanson was a very innovative and clever designer.
By the way there is a 30' sportboat on the hard at airlie beach yacht club that I bet is one of his designs. It is slowly rotting away but could be restored if someone wanted a project.