I still think you could hook two Moths together with carbon beams, add a tramp, dump the wings, figure out how to manipulate both sails and you'd have a
poor man's
foiling cat that would be a lot more stable than the single hull Moth.
1, boats need to be LIGHT to remove drag from creating loads of lift to fly -> Small boats
2, boats need LOW air from drag -> small boats
3, once a boat is flying, we need a low drag (and low power) rig as form drag is low, thus as we do not need lots of power, we do not need lots of RM to control it ->Thin boat once airborne as less aero drag
4, as we do not need lots of power once foiling, we do not need wide (and so draggy) boats ONCE FOILING, but we need a boat that can create RM when needed, but have low form drag when flying - We need wings!
5, Small, not very wide boat, but with wings to create RM when needed = MOTH!
Makes sense to me. However, if the Moth class allowed foils in the wings, the Moth would become more stable and, as a consequence, faster in a wider range of conditions.
From that point the boat would evolve into a trimaran.
Conclusion: cats may not be the ideal foiling platform, but this does not mean that monohulls like the Moth are
the
thing. Trimarans look like a better choice nowadays.
1, boats need to be LIGHT to remove drag from creating loads of lift to fly -> Small boats
2, boats need LOW air from drag -> small boats
3, once a boat is flying, we need a low drag (and low power) rig as form drag is low, thus as we do not need lots of power, we do not need lots of RM to control it ->Thin boat once airborne as less aero drag
4, as we do not need lots of power once foiling, we do not need wide (and so draggy) boats ONCE FOILING, but we need a boat that can create RM when needed, but have low form drag when flying - We need wings!
5, Small, not very wide boat, but with wings to create RM when needed = MOTH!
Makes sense to me. However, if the Moth class allowed foils in the wings, the Moth would become more stable and, as a consequence, faster in a wider range of conditions.
From that point the boat would evolve into a trimaran.
Conclusion: cats may not be the ideal foiling platform, but this does not mean that monohulls like the Moth are
the
thing. Trimarans look like a better choice nowadays.
Depends on the definition of Tri....
If moths allowed foils on the ned of the wings, you might end up with either 2 foils (as per
Blue arrow
) that allow the boat to create massive RM. OR, you might have 3 foils:
one on each wind to create RM and one in the middle hull to control
Ride height
.
Maybe..............
lets go!
. Preferably with the current aesthetic looks.
Reason I think it is a dead end: Power to weight ratio is not large enough on the common beachcat to give best performance around a course. (I am very narrow minded, thinking about racing only, I admit that)
I have heard anectdotes like taipanfc gives about moth speeds relative to cats, but I have still not heard about a
grugde match
where moths were faster around the course. I dont doubt that the moths can be faster, just never seen any non-biased reports of top moth sailors racing top cat sailors on the Tornado or similar and beating the T? Or M20 or any similar really high-perf racing cat.
In August last year on Sydney harbour, the moth beat the all the A-Cats in 3 out of 4 races. The first placed A was Steve Brewin who is a quite handy sailor.
Here in Singapore we had a couple of races that were informal (no results taken). More of a reaching course. 3 lap race. First leg to the top I couldn't foil so the F16s scooted away. Then the breeze came in from the side so all boats got fairly much at the same time. F16s were close to a leg away. Once I could foil i easily caught up and won by over a leg.
At first i was sceptical that the moth was that much quicker than an A/F16, but it truly is, with the caveat of the right conditions of course <img src="<>/wink.gif" alt="wink" title="wink" height="15" width="15" />
I'll stick to conventional cat design wisdom for as long as moth doesn't show up at an open water distance race, get out through the surf and beat 51% of the cats around the course.
I don't think it will ever happen. Mind you the Australian portsmouth rating for the foiling moth is 20% faster then the non-foling moth but still on a par with the Hobie 16's
'nough said.
Wouter
Look at blog post for June 3, www.rohanveal.com Also has link to the results.
In another single-handed dinghy regatta (no cats), the moth would have still won if handicapped at 51 on VYC. (Source somewhere on SA).
As for getting out through the surf on a moth, well not going to happen. Unless you want carbon pieces all along the beach, haha.
Someone will try foils on a cat. My personal opinion is let some tinkerer/boat nut work out the details of how it works as it will be costly to develop with a lot of time taken up.
In August last year on Sydney harbour, the moth beat the all the A-Cats in 3 out of 4 races. The first placed A was Steve Brewin who is a quite handy sailor.
Do you have a link to the event? Not going to nit-pick details but I would like to see it confirmed that the Moth is faster around the course than high-perf cats, when comparing apples to apples.
In August last year on Sydney harbour, the moth beat the all the A-Cats in 3 out of 4 races. The first placed A was Steve Brewin who is a quite handy sailor.
Do you have a link to the event? Not going to nit-pick details but I would like to see it confirmed that the Moth is faster around the course than high-perf cats, when comparing apples to apples.
Never saw official results online and I don't think there were any, just reports posted on SA from actual participants on that weekend.
Biggest problem is that multi-boat regattas seem to be exclusionist between cats and dinghies. So going to be hard to find results. But look at the results on the Rohan Veal link. The first 14 skiff guy is one of the top guys at the worlds. All I can say that once foiling the moth is crazy quick in reality to what you would expect. Going deeper downwind than cats with kites and main sheeted near centre and hiking hard is awesome to do. (But trying to sail in non-foiling conditions is an absolute pain and chore).
G'day Rolf we had Greg Wise on a Foiling Moth come here last January for our 15km downhill run from Cape Jaffa. The F18 crossed the start line with spin but not enough wind for the Moth he sat in the water long after I was gone then flashed by at much wider angles than us but unbelievably fast. The wind came up and he caught the leaders at the rounding mark but then the wind dropped out and he went slow up hill so he came 3rd. These photo's show the sequence, the moths in the water as they cross the line in the first photo. The whole fleet's gone in the 2nd and he's caught them at the rounding mark but no longer foiling in the third. As soon as there was enough wind for the spin guys to get on the wire the moth went unbelievably fast. Most of us at the club want to try one.
Notice the F18 is not even in the second photo it was long gone
regards
To all (and not specifically to James)
Just for the record.
I do think the moths are very exiting sail craft and really respect the guys that developped the full foiling moth into a viable alternative to the non-foiling moth.
The fact I have serious doubts about a full foiling catamaran doesn't mean I look negatively upon the moth themselves.
I do believe that partial foiling like the ORMA tris and the John de Vries special are doing is viable for large cats. This involves bruce foils (or curved foils) and only lift the boat up by say 60% at their absolute full speed.
The reason for this are the control issues that arise when more of the boat is lifted and a positive feedback is created between the rise of the hull and increasing the angle of incidence of the foil which in turn ... well the famous foiling jump.
I also have a question for James. Do you feel the VYC rating of 84 is correct for the Moth, considering it is an average that is to be taken over all windconditions ?
Wouter
And as for costs of the foils, on the Bladerider and Mach2 the foils and the foil set up contribute to half the cost of the boat (retail is US$14k-$17k). Adding that cost onto the current price of the A would mark things out of reach for an already successful class. Plus the current A class masts couldn't withstand more than a couple of crashes from foil ventilation as you certainly hit the piss hard when crashing.
Foiling has yet to be seen quicker around the bouys for a cat. The Canadian C Class guys gave it a good go and found that the non oiling C was a bit quicker. With a bit more development they may eventually get there, but will they ever become quick enough to justify the poor low wind performance.
Foiling C Class Thread - http:/
![[Linked Image]](http://www.sailinganarchy.com/fringe/2007/images/Rocker%20in%20flight.jpg)
In August last year on Sydney harbour, the moth beat the all the A-Cats in 3 out of 4 races. The first placed A was Steve Brewin who is a quite handy sailor.
Do you have a link to the event? Not going to nit-pick details but I would like to see it confirmed that the Moth is faster around the course than high-perf cats, when comparing apples to apples.
I don't think the reults are available on line any more but I was there as a spectator that year (as I just sold my Cap).
The Moth guy was one of the very top Moth sailors and as we know, Stevie can sail an A OK.
The conditions were enough for foiling each race with the second day from memory being fresh. It was a typical winter regatta on Sydney Harbour and the wind was very shifty. Stevie was edged out by the moth for both handicap and line houners in this regatta. When I discussed with him, he said he was supprised with the pace of the moth and said he was a little quicker in this regatta (because he won). Boat for boat I believe they are very close, perhaps equal in these conditions. The shifty nature and better tactical decisions may have also lead to the Moth winning the regatta, however I think you will find they are about on par.
The previous years, the Moths did not even come close to the cats in any race however the conditions ranged from non foiling on one day and blowing on the next with holes of no breeze...... Typical Winter Sydney Harbour. The last year I raced, only an 18 beat us for line hounours in one race (where we started late and gave him a 1/2 leg lead on the first upwind. Every other race we took line honours by 3 to 5 mins from an 18 with all other boats not even close.
TaipanFC, when he raced at our club was a very passionate (and very quick) Taipan sailor. In Singapore he has both an A Class and a Moth so will give you a very fair analasis of both boats.
Just for the record.
I do think the moths are very exiting sail craft and really respect the guys that developped the full foiling moth into a viable alternative to the non-foiling moth.
The fact I have serious doubts about a full foiling catamaran doesn't mean I look negatively upon the moth themselves.
I do believe that partial foiling like the ORMA tris and the John de Vries special are doing is viable for large cats. This involves bruce foils (or curved foils) and only lift the boat up by say 60% at their absolute full speed.
The reason for this are the control issues that arise when more of the boat is lifted and a positive feedback is created between the rise of the hull and increasing the angle of incidence of the foil which in turn ... well the famous foiling jump.
I also have a question for James. Do you feel the VYC rating of 84 is correct for the Moth, considering it is an average that is to be taken over all windconditions ?
Wouter
I don't think ratings will work well for Moths as their performance is not consistent for all conditions. When not foiling then I am as quick as a Laser if I am lucky and they rate over 100 in VYC. When foiling in a wind range of 8-12 then no cats can get close as you are still powering up. 20+ is survival mode in the Moth (at least for me) and lots of issues with just keeping the mast pointed upright whilst the boat is going like a scalded cat (awesome fun though and scary). If you don't have your foils set up correctly for lift then prepared to be lightning fast with a massive crash at any moment.
As for foils on cats. Will happen. I don't think the current approaches have worked or were the best ideas, but I don't know what the alternative will be or should be. Someone I am sure will get the lightbulb idea and make it work.
Drag is the big issue, but also auto-adjustment on the fly too. The amount of time I spend adjusting and re-adjusting the foils is quite significant. Really set it up for the conditions, wind and wave. All down to the gearing and how it reacts. So for a cat with 2 hulls this could become a fine art.
Thanks for answering my question James,
Actually about 2 year ago I propose the control of a foiling Moth as a 2nd year design assignment for control systems students at my university. I thought it was an excellent concept vehicle to have them try to design a proper controller to ease the load of the sailor. I feel that relatively simple control concepts can go a very long way in stabilizing the Moth while sailing
The problem with a catamarn is of course that it will have two foils (each in one hull) and that leads to a multivariable control situation where control actions on one foil setup will have a noticable effect (disturbance) on the other foil setup. This is typically a difficult control problem to solve.
I feel hydroptere is on the right track with regard to a viable full foiling multihull, but I don't think it is a very good windward/leeward racer. Its bruce foils provide a level of automatic control that you just don't have with T-foils. That is one reason why foiling motorboats often used the V-foil setup.
I am however convinced that the path to succesful foiling requires the assistance of a skilled control systems engineer and that had been lacking up to now. The rave was apparently hard to control and only the Hobie Tirfoiler seem to have gotten the T-foil setup working right on a multi hull. I think that was mostly due to the way they had implemented the control setup.
But I wish everyone who tries the best of luck.
Wouter
The problem with a catamarn is of course that it will have two foils (each in one hull) and that leads to a multivariable control situation where control actions on one foil setup will have a noticable effect (disturbance) on the other foil setup. This is typically a difficult control problem to solve.
Alinghi seems to be raising its windward foil all the time. It requires crew work, but eliminates this problem.
I am however convinced that the path to succesful foiling requires the assistance of a skilled control systems engineer and that had been lacking up to now.
Agreed. The ORMA 60s have no control system, though. I think there is a good possibility that symetrical section T or L foiled rudders combined with S foils would be a self-stabilized setup.
Yes, but someone with skills in this area still has to design it to the proper dimensions for it to work well.
Wouter
Sounds like you just volunteered.
😛
Yes, but someone with skills in this area still has to design it to the proper dimensions for it to work well.
Or add flaps to the rudder foils in a prototype and keep prototyping and testing until the flaps are no longer necessary.
Wednesday club races tonight at DWSC: 10 knots of wind or so. A varied set of boats around a triangle course. After an hour racing:
After 4 laps a Hurricane 5.9 finished first, I was further behind by 3/4 minutes, two other F16 and another hurricane finished in the next 4 minutes behind me, a well driven solo Dart 18 shortly behind them. The moth, a bladerunner, finished right behind me, before the other F16. But the bladerunner lapped *everyone* but the first two cats.
He was first to the windward mark by a mile, by the C mark when I rounded the B mark (I was second at that point) and then just gone.
So in one hour, the moth did 5 laps, we fast cats did 4, the asymetrics where somewhat behind us but on 4 laps as well and the slow boats (laser and all) did 3 laps.
Foiling: way faster.
We don't have the results yet, but they will be posted there hopefully sometimes tomorrow.
Yeah but what is the rating for a Bladerider compared to a 110(?)kg F16? It only weights 30kg right?
I was mostly interested in pure speed around the course and it sounds like it is faster when it can foil. Assuming sailors are competent of course.
Probably more like mid-30s. The home built ones can be sub-30, but you find those guys spending each evening repairing the boat.
Only has an 8 sq m sail. F16 has 13 sq m or so mainsail, 17 sq m spinnaker, plus a jib too... I am sure Wouter has the exact numbers to divulge here.
Haha, big understatement about competency. I have capsized more in the first 3 months of owning a Moth than I did in my whole 20 year sailing career combined. I think I capsized 5 times or more just getting out of the marina the first day and that was a distance of 100m.
Good point !
But first I have to finish some other projects I'm afraid.
Worth considering though !
Wouter
Rating Moth
If you punch in the moth numbers in the Texel rating calculator then you get a rating of 130 (=about the same as a Hobie 14); but of course this calculator assumes that the hull is fully in the water.
When converting the VYC rating to Texel you get 118 (= on a par with a Hobie 16)
Wouter
If you punch in the moth numbers in the Texel rating calculator then you get a rating of 130 (=about the same as a Hobie 14); but of course this calculator assumes that the hull is fully in the water.
When converting the VYC rating to Texel you get 118 (= on a par with a Hobie 16)
Wouter
Depending on LOCATION and also Sailor Skill.
PY rating (NOT SCHRS) is nywhere between 900 (slow) and 650 (Fast). For comparison
F18 is about 691, F16 is similar and the Tornado is 650.
Problem in the UK is that we have very few (if any) Tornado's that club race against the moth, and no really decent teams doing this limit club racing.
Is the Moth quicker than a Tornado around the course? No is Sub foiling for the Moth. Similr in ideal MOTH foiling conditions and when howling the T will win.
Still very good for an 8 foot boat!!!
That's the first time we had a Moth on our Wednesday race, and unfortunately our only active Tornado team was not on the water. They are good, they finished second at the last national if I remember correctly. And they usually lap everyone on our relatively short courses.
Hopefully, one of these days the two of them are going to be on the water at the same time with a decent amount of wind...
I don't see what difference it makes as I never expect to see the two (cats vs. moths) on the same starting line, except maybe a fun club type race.
Each type (cat vs. foiling moth) has it's own
perfect conditions
for going maximum speed, I doubt it is the same for both boats, so you are still comparing apples to oranges. Which ever boat the prevailing conditions favor will do better, obviously.
Any results to actually divulge from this? Control systems for the Moth are still being actively developed and will do so for a while to come.
As with so many things at the university it disappeared into that big black hole.
They did put a PHD student on the idea to see if he could develop it into a viable assignment. He contacted my once, I gave him a very good head start on nearly everything and then he disappeared of the face of the world. I dare say that he did the motions in order to not upset the professor who gave him the assignment but other then that deep sixed it.
May be contact me in 6 months or so and see if I'm still tickled by it ? Till then I have my hands full in getting the final report on my other research accepted.
Wouter
Hopefully, one of these days the two of them are going to be on the water at the same time with a decent amount of wind...
I have to concur with Pepin, the Mothie simply blitzed us last night, so much so I want one but being a biggie fat arsed sort of bloke, it aint going to be a Moth. Seriously though I was impressed with the speed and handling of the Moth, the upwind was not as much as a problem as I thought it would be for him, really dramatic to watch as he lapped me, the really deep starting angle ( speed ) and then the really arched curve onto the remainder of the tack ( building apparant wind ).
In the right wind conditions ( to be fair we couldn't really wire properly last night with about 8 knots to 12 knots at times wind ) the mothies are going to blitz some race records. I think with another year or two of development, they are going to pretty special.