I thought it would be best to start a new thread for this proposed new class.:diablo:
Here is the link that will put you in the picture…:blindfold:trouble::timebomb:
Did I miss something?
Where does it say the the LWL is limited to 1000mm? Or isn’t it?
No limit on LOA or LWL. No limit on anything about the hull, really, except monohull, draft (380 mm), vertical centre of gravity (245 mm), one keel, minimum displacement (4250 gm), and no hollows.
Well I have got my PHIGIT all set to go. :rolleyes:
Well not quite finished yet, but certainly a concept which I would like comments on.
I own a hull of a 1989 10 rater design by Roger Stollery called “Chicken” which I think will make the perfect hull for the PHIGIT class.
LOA = 1633mm.
LWL = 1200mm.
Designed displacement = 5.9 Kg.
Now my question is, what effect on performance will the lightening of the bulb make, apart from the obvious change of stability?
Will the hull floating higher and with that the subsequent shorter load waterline and narrower beam have any unbalancing effect?
I should explain that this design is a double ender. (sharp at both ends):graduate:
Do you think dear reader, that making the bulb down to minimum weight is the go, or should I choose the design bulb weight of 4Kg and just mount it on the shorter IOM length fin?
So much to think about and so little time.:scared:
Am I correct to assume that the proposed class might allow an existing marblehead class hull for example to reduce draft, and rig and be able to compete? If this is the case then surely this proposed class is dead before it starts due to the killer of all forms of yacht racing, - money! I see a note in Lesters comments that weight should not be to critical, to get any sort of performance weight is always an issue, so I see again a rush to build hulls in exotics that will see the proposal fail.
Sounds negative? possibly, but isn’t one of the problems with the whole radio yachting thing, too many classes? The one proposal I liked was Lesters wooden/chine hull IOM thoughts. At least the prospective builder/owner had the opportunity to get started in the class and race against like minded people and if a good enough skipper, compete with the hotshots.
Just my thoughts on the new class thing.
You could use a M hull, sure, but not the rig and probably not the fin.
If this is the case then surely this proposed class is dead before it starts due to the killer of all forms of yacht racing, - money! I see a note in Lesters comments that weight should not be to critical, to get any sort of performance weight is always an issue, so I see again a rush to build hulls in exotics that will see the proposal fail.
You might need to read the MMI article before commenting further. The Phigit has a vertical centre of gravity check – so you can throw any amount of money at reducing or even redistributing weight and it won’t help…
isn’t one of the problems with the whole radio yachting thing, too many classes? The one proposal I liked was Lesters wooden/chine hull IOM thoughts. At least the prospective builder/owner had the opportunity to get started in the class and race against like minded people and if a good enough skipper, compete with the hotshots.
I quite liked those thoughts as well (smile), but they never happened. So this is another attempt to capitalise on the IOM “one-design rigs” while giving a home builder something to get their teeth into.
Lester, I have a great deal of empathy for you right now. Starting a new class is not an easy task!
Regardless of the great deal of thought and discussion that went into developing your rules (some very clever ideas there, by the way) there will be people who would rather see it their way. Instead of using their creative talents to participate within the class boundaries, they prefer to use that talent to point out where you were wrong. Wrong, of course, means anywhere you made decisions that differ from their preferences.
I’m not writing this to criticize the detractors. I’m sincere about that. They have the right to disagree, and this is a good forum for such discussion. I just thought you might appreciate knowing that I think you did a good job, and I wish you well in your Phigit endeavor. Maybe I’ll start playing with some ideas for boats a bit longer than my latest concentration!
All the best, and thanks for all your contributions to our great sport.
I totally agree. I especially think the VCG measurement is a great idea.
I guess, like a lot of classes, there will initially be a great variance of design. Over time though this settles down into a “corner” of the rule and the boats start to become more similar. What is interesting however is when a boat from a predominately windy area meets up with a boat which is designed for lighter conditions.
My only suggestion would have been to limit LWL and keep the LOA free. I reckon boats with overhangs always look more gracefull and have a better motion, but hey, thats just my opinion.
Good rules and hopefully the class will develop.
I’ve been inveigled (ot I think I have - Lester is such a superb operator [YES I LOVE YOU, YOU BLOODY ROOINEK] ) into designing and building a Phidget. I’m not sure about the overhangs being particularly graceful - they’re quite long but with such a low displacement/length ratio they cease to be useful once they get far above the waterline - so very low overhangs brutally truncated where they cease do do anything useful. The fact that no hollows are permitted makes it harder to design very long overhangs that are any use.
In the course of the design process I’ve played about with three sets of ‘copycat vanilla’ IOM hull lines - wide, medium and narrow beam. What is really surprising is how much an IOM’s wetted surface goes up if you increase its displacement by 250 g.
My guess for UK conditioins (calmer than Australia, windier than the US) is a beam of about 15 cm, WL about 1.22 m, LOA 1.45 m.
I agree that design will find a ‘corner’ but for the moment taking an IOM as a benchmark and working out what to do with an extra 250 g without anymore sail area to push it around is quite interesrting.
When all’s settled, I go off and produce my A or 6M - that’s real ingenuity for you.
Heres my first effort.
wl beam 180.
might be a bit fat and short on wl.
Won’t be building it anyway.
Bill Hagerups Phidgit
LWL 1204 (extends to 1294 at 30 degrees heel)
"Just to start things going, I am intrigued why the rule doesn’t like hollows. The only area where they could conceivably be of any use in bending the rule is around the root of the fin since that effectively is the only measurement point on the hull. One would have thought that any performance bending oddities in that area could have been overcome by less draconian means.
Otherwise restrictions on hollows are generally used to outlaw distortion of the effect of 1/4 beam lenghs, girth stations, depth stations and the like. Since there aren’t any of these, the only effect under the Phiget rule can be to reduce performance for no very apparent reason.
Just a thought!
Probaby better to reply to the official Phiget site abve,
Just to go with Footy projects, construction of this brute is imminent.
Hull looks good. Just wondering why you would have overhangs rather than a maximum length waterline?
If you have a LWL of 1.226m and an LOA of 1.53m wouldn’t a hull with a LOA and LWL of say 1.4m be lighter weight and have basically the same sailing length?
Just a thought…
Thanks for the thoughts.
The problem, I think, is that a Phiget will inevitably be measured against an IOM with which it shares a rig, It has 250 g more displacement so acceleration will be lower anyway (which was intended by the designers of the rule). We gain effective sail carrying power by being longer and having a slightly ‘cod’s head, mackerel’s tail’ configuration. But we must do this without increasing wetted surface too much - otherwise we have something that will (hopefully) whip the arse off an IOM upwind and down if it blows but is dead as dog in light airs. Hence the overhangs - as soon as the boat starts to move above ghosting speed, they should become sailing length.
I see where you are coming from, i guess it really is a case of horses for courses, and trading of lower resistance in a blow versus less wetted surface when its light.
One thing that sticks in my mind, and it may or may not be applicable, was team New Zealand in the 95 cup. NZL 32 was a very long boat, i believe she actually copped a sail area penalty as part of the trade off, but was still very quick (obviously) in the light air.
Now i know there are many, many variables but she always sticks in my mind as the odd one out in the whole “reduce wetted surface in the light” theory.
Also your point about heeled versus static WL length is a valid one.
I’m not sure, but I think Team NZ had a very narrow waterline did she not? Hence low wetted area.
Given that we’ve got 250 g more displacement than an IOM, we’ve got to put it somewhere and the only sensible place is longwise - into more length. To keep the wetted surface down, you have to cut beam, so make the hull run efficiently at high angles of heel - hence the tumblehome. If we try to go for ultra-low wetted surface sections (i.e. semi-circular) we either end upwith damn all stability or too much flare so that the boat rolls her ends out of the water - i.e. the overhangs endup doing nothing. Obviously this is not the only solution, but I think it is probbly a valid one until we see how the rule develop.
Agreed, there is a lot to be learned by just building it, huh?
You’re the guy with the CNC system? In a few days I should be able to produce a URBL file f you want to have go at building one. No charge!