New 27' trimaran design by Kurt Hughes

[cavalier mk2]

The higher the entrance the better works great from one angle James but I've noticed amas into a wing don't bottom out at all, they start working like a scow on those momentary heavy loads. A Newick wing section like the maligned 3 Cheers would do as you say to get things up and out and have enough area to keep things dry and the aluminum beams for low cost demountability could fit at deck level. It would be worth it to try both approaches. When a ama goes under the deck is surface area drag with no lift. When a ama wing hits, the deck is mainly dry and the extra area of wing is adding lift. So I think there is plenty of homework to do, In a couple of the video frames you can see the 24 just about stop from burying things so anything might help.

 

[cavalier mk2]

I should add that these suggestions are more for the existing 24 to use as a test bed. Certainly the 27 isn't breaking new ground as it incorporates current thinking. Me too boats are a safe bet until the racers iron out the next innovations but they don't really take into account the crew comfort angle.

 

[silentbay]

Salve Simmo,
Your construction method sounds like a good idea, vac bagging is worth the extra effort and once you get the hang of it not much more difficult to pull off.

In Australia we normally use either club handicaps or the OMR rating system which is based on the US texel system. In general it gives pretty good results it's tough for the really top boats to win though as they take a substantial hit on handicap but given the right conditions they can still occasionally come out on top. There is also the Portsmouth yardstick system which seems to work quite well as a guide to handicap however I'm not very familiar with it. Currently the OMR rule does not penalise lifting foils or beam but that may be changed in a future version of the rule. For now they are just gathering data.

http://www.mycq.org.au/OMR/

Your rig size idea sounds good. Somewhere between the extreme and moderate is good. If I recall correctly OMRA 60 trimarans were looking to tie in a reef somewhere around the 5kt windspeed mark so 12kt is a good compromise.

I assume Cat A would be equivalent to our Cat 1 regulation. Most coastal and offshore races would require somewhere around Cat 3 (Cat C?) which is not difficult to achieve.

Ciao.

orma 60 take a reef in 5 knots of wind???!!! Really?

 

[Corley]

I'll see if I can find the article and scan it. A very interesting read, I think they reefed at 5 knots when singlehanding by the way not fleet racing with crew there they just pushed the boats as hard as humanely possible.

 

[silentbay]

that's insane!

 

[catsketcher]

ORMA and reefing

On my only sail on an ORMA - KAS from Gold coast to Sydney- we reefed at about 15 knots. Full main upwind (90 % headsail) in 12-15 knots of breeze. You really do need someone on the mainsheet at all times. Flying main hull is very very easy. IIRC we put the reef in at about 15-16 as the main hull got very light.

cheers

Phil

 

[Corley]

Thanks phil, that sounds about right they tended to tuck in reefs sooner when singlehanding for a measure of safety if you see any videos of the boats on single handed transats or Route du Rhum etc it has to be almost dead calm before they have full sail up. It's a very powered up platform 100' mast on a 60' multihull.

 

[silentbay]

Here some 27 new point of view from kurt and the difference between the old 24 and the new 27...

 

[silentbay]

I now asked him to extend the cockpit toward the stern, moving the back beam closer to the transom, and to make the mainhull wings smaller and narrower...attached some bad draw to understand better

 

[Corley]

Thanks for the updates Simmo, looking good!

 

[silentbay]

No worries mate!
Where about in Australia u from Corley? I've been many times over there for surfing, first time I spent 1 whole year travelling around by van...I love that place I wish I could live over there!!

 

[yves]

How does having the centreboard below the boom works ?

 

[Corley]

I'm from Melbourne the largest city in Victoria, it's the cold bit on the South East corner of Australia which is North of the next coldest bit Tasmania. Our racing and cruising grounds are directly adjacent to the sometimes nasty Bass Strait which has rather a fearsome reputation for nasty seas and gales but has some very benign times as well. On our West Coast we have some pretty famous surf beaches such as Bells Beach and Janjuck. Let me know if your coming over again, always like meeting any multihullers who venture down this way.

Cheers!

 

[silentbay]

I'm from Melbourne the largest city in Victoria, it's the cold bit on the South East corner of Australia which is North of the next coldest bit Tasmania. Our racing and cruising grounds are directly adjacent to the sometimes nasty Bass Strait which has rather a fearsome reputation for nasty seas and gales but has some very benign times as well. On our West Coast we have some pretty famous surf beaches such as Bells Beach and Janjuck. Let me know if your coming over again, always like meeting any multihullers who venture down this way.

Cheers!

Nice! I've been there! I also drove thru the great ocean road twice going to Perth thru the Nullabor! If i'm gonna come back i'll let u know for sure!

 

[silentbay]

How does having the centreboard below the boom works ?

It's a bit annoying when u sail downwind and u want to keep the daggerboard up...especially when jibing, infact I asked kurt to put it sloped head the mast but he sticks with his philosophy that that's better.