Foiling F-Boats

teamvmg

Super Anarchist
1,973
104
It's probably a combination of boredom from not sailing much due to the pandemic, plus online coverage of the America's Cup, Vendee Globe, and Jules Verne Trophy, but this all has me curious about the plausibility of full foiling kits for Farrier/Corsair boats. I mean there's a full foiling kit for the Laser, so why not?

There is a lifting foil kit for the F-85SR/F-82R on the F-Boat Store, but it's not a full foiling kit. 

It looks like the Ultime's have T-foils on the main hull and rudders, plus L-foils on the amas. There's obviously a ton of complexity with these boats that would be infeasible to translate directly a Farrier/Corsair kit, but what about something like this:

  • T-foil on main dagger board with wand-style elevator control (like Moth or Laser kit)
  • Fixed T-foil on rudder (again, like Moth or Laser kit)
  • Fixed L or C foils on amas (like F-85SR/F-82R kit)
  • Possibly fixed T-foils on aft end of amas to increase stability and/or reduce pressure on rudder?

This may be a really dumb idea, but I do take some comfort that it's at least not as dumb as this.

Flame away!!!
Don't forget to strengthen the beams too

Then take a massive handicap hit

Get extra crew on board to run the foils

Then only foil for 5% of race time 

Carry more drag and weight for the other 95%!

 

Wess

Super Anarchist
Don't do this to an F or C boat.  Not worth it and would require massive re-engineering and reinforcement for little or no overall (across range of conditions and courses) gain.  And at the end of the day and huge cost your resale value would be minimal.  If you want full foiling go buy a boat designed and built specifically for  that.  Will cost you less and get you more that trying to convert an F or C boat (both great boats/brands for what they are designed and built to do).

 

multihuler

Anarchist
809
287
Reno
So, that means the F32 Carbon Credit for sale in oz built around the foils, and tiny cabin doesnt work?

If you want to  critique you could at least look it up 

 

can-UK

Member
136
44
Dubai
I have an Fboat and my benchmark for performance upgrades has always been the Seacart 30.

The Seacart 30 does not use lifting foils (I am aware of 2 that have been modified.. but these are exceptions).

Would adding foils to an fboat make it as fast or faster than a Seacart?  Would the cost of adding foils to an fboat (+ boat value) exceed the purchase price for a 2nd hand Seacart? 

I always wondered what the cheekee monkee line honours programme would have looked like if they didn't move to foils and focussed on light high volume carbon floats and T rudders.

Adding foils to an fboat not designed around them is always going to be a tough and expensive learning curve.  But don't get me wrong.. I have followed cheekee monkee for a long time and have been inspired by that programme..

 

REW

Anarchist
928
59
Thats a great write up.
Agreed, great write up.  BTW Cheekee ended up with new lighter beams, we built a new, lighter wing mast 2.5 feet taller than stock with masthead screacher and kites, rig canting and adjustable rake.  The end result was clearly not how one would do it if starting from scratch.  Couldn't beat a well sailed stock sea cart 30 which I agree is a great benchmark.  One thing we had going for us though was the ability to rig and launch from trailer to sailing in a little over 2 hours.  Based on the number of events we did over a pretty wide area this was a huge deal for me.  

 

cynophobe

Super Anarchist
2,472
38
Airlie Beach
So, that means the F32 Carbon Credit for sale in oz built around the foils, and tiny cabin doesnt work?

If you want to  critique you could at least look it up 
It doesn't work. It did win a national title against other boats that had never achieved a 3rd in a nationals. Beautifully built but massive design flaws. 

 

martin 'hoff

Super Anarchist
2,180
1,053
Miami
IMHO past a certain point, foils are a massive liability. Essentially, anything you can right on your own, anything that capsizing / pitchpoling violently firmly is a serious matter. At certain speeds/swells/conditions, stopping is a mission.

Fly as high as you dare on a moth/wasp/ufo. Go wild on an acat, it's super light. People get hurt on a Nacra 17. Weights and loads in a TF10 give me real pause. The foiling G4 is glorious dangerous folly.

 

SailingTips.Ca

Feigns Knowledge
790
342
Victoria, BC
It doesn't work. It did win a national title against other boats that had never achieved a 3rd in a nationals. Beautifully built but massive design flaws. 
I think it's hugely telling that the semi-foiling boats haven't just walked away with the titles.

Agreed, great write up.  BTW Cheekee ended up with new lighter beams, we built a new, lighter wing mast 2.5 feet taller than stock with masthead screacher and kites, rig canting and adjustable rake.  The end result was clearly not how one would do it if starting from scratch.  Couldn't beat a well sailed stock sea cart 30 which I agree is a great benchmark.  One thing we had going for us though was the ability to rig and launch from trailer to sailing in a little over 2 hours.  Based on the number of events we did over a pretty wide area this was a huge deal for me.  
Also telling that Cheekee Monkey still couldn't beat a stock Seacart 30. I bet Cheekee Monkey would have been just as successful without the foils.

I've talked to a couple of semi-foiling boat owners (not F-boats but similar size range), and when I asked about their foils, they both answered "Ummm...yeah...the canting mast works really well!".  That's why I was musing about full-foiling (e.g. T-foil on daggerboard) because I'm not aware of anybody ever trying that on a smaller tri. 

I have an Fboat and my benchmark for performance upgrades has always been the Seacart 30.

The Seacart 30 does not use lifting foils (I am aware of 2 that have been modified.. but these are exceptions).
The Seacart 30 is an amazing boat, but the ability to sail an F-boat from the trailer is a huge logistical advantage A T-foil on the daggerboard would certainly introduce some trailering challenges, thereby eliminating the logistical advantage of an F-boat.

IMHO past a certain point, foils are a massive liability. Essentially, anything you can right on your own, anything that capsizing / pitchpoling violently firmly is a serious matter. At certain speeds/swells/conditions, stopping is a mission.
Martin makes an excellent point and in the end, even if you could make it work, you may not even be allowed to compete in your favourite events with a full-foiling boat for safety reasons. 

 
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SeaGul

Super Anarchist
1,361
106
Oslo Norway
SeaCart 30 vs Carbon Credit; the SC30 is much lighter - and very stiff - but look at the floats - the typical F-floats that also this CC has is made for safety - not speed - also the main hull has som design features that is about safety , due to the market the F-boats has - not speed. The SC30 is made just for speed and for expert sailors. 

 

REW

Anarchist
928
59
6 hours ago, REW said:
Agreed, great write up.  BTW Cheekee ended up with new lighter beams, we built a new, lighter wing mast 2.5 feet taller than stock with masthead screacher and kites, rig canting and adjustable rake.  The end result was clearly not how one would do it if starting from scratch.  Couldn't beat a well sailed stock sea cart 30 which I agree is a great benchmark.  One thing we had going for us though was the ability to rig and launch from trailer to sailing in a little over 2 hours.  Based on the number of events we did over a pretty wide area this was a huge deal for me.  


Also telling that Cheekee Monkey still couldn't beat a stock Seacart 30. I bet Cheekee Monkey would have been just as successful without the foils.

I've talked to a couple of semi-foiling boat owners (not F-boats but similar size range), and when I asked about their foils, they both answered "Ummm...yeah...the canting mast works really well!".  That's why I was musing about full-foiling (e.g. T-foil on daggerboard) because I'm not aware of anybody ever trying that on a smaller tri. 

Cheekee was markedly faster with foils than without unless wind speed under 6 to 7 knots.  beyond righting moment they really helped the boat to weather (faster closer).  we carried a masthead screacher upwind that would have blown us sideways without the foils. Reaching and offwind at 10 knots of boat speed plus the foils were fast and also allowed more sail area at higher wind speeds.

The struggle was that the rating guys never like a bunch of mods, so the rating was punitive.  Even though I chaired the regional rating group, I recused myself regarding my own boat.  I don't blame them.  When you take a a stock boat that is a known quantity and modify the daylights out of it it becomes an insurmountable challenge for a PHRF type rating system.  The sum of 3 second increments for a bunch of mods doesn't equal the final reality.

The Seacart has a higher rig, more sail area, more float buoyancy forward and lower displacement....by alot.  Good formula!

 




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