Trailerable Trimarans

Hello: I am new to this site, but am impressed with what I am seeing here. I sail a WindRider17 in the Gulf of Mexico, and am looking to step up in size. The logical choice would be a Corsair or a Dragonfly. Is there anyone out there with experience with one? Thank You Thomas Rheuble Rheuble@aol.com

[tspeer]

I am a part-owner of a Corsair F-24 MkI, and I've sailed on an F-27 and F-9's. I highly recommend the Farrier designed trimarans. They are great boats and you can get some terrific deals right now.

[tspeer]

p.s. You can find reviews of most of the Farrier trimarans (built in the US by Corsair) at http://www.sailingsource.com/boatreviews.html.

[tspeer]

Here's a post from a new F-27 trimaran owner to the Mulithulls mailing list (note: pretty much all the F-boats have a roller furling/reefing boom, and some have slab reefing installed in addition):

I'm really impressed with my new (to me) F-27. Having sailed dinghies, leaners, Hobie Cats and cruising cats there is NO DOUBT we made the right choice getting an F-27. The speed is great for me and the accommodations and stability suit both me and my wife.

We picked up the boat (no. 420) in Seattle (thanks Wayne) and launched from Bellevue for three days and two nights in the San Juans. Temperatures were in the 30s and 40s, wind blew in the tens and twenties, it rained a little, hailed a little and we had a great time. We hit 14 within one hour of launching sailing under main and screecher. Then furled the screecher without too much difficulty.

Towed back to Denver with no problems (Chev 2500 LWB Pickup).

Keeping the boat on a slip at Cherry Creek Res.

Took the inlaws out - mother in law gets motion sick in a car! We were doing 12 knots while they sat below eating dinner which my wife had just cooked! Granted the lake is small so biggest waves are from speedboats but try that in a leaner!

On Sunday my wife and I sailed in winds gusting to 35knots. We started with just the main reefed to the first (and only reef points). I single handed with the help of the auto pilot while my wife graded papers below. No problems other than I had to help the auto pilot tack. I then rolled in most of the main - slowed up just a bit but the boat was still very manageable. Then I rolled up all the main and sailed under jib alone - still no problems - the auto pilot even managed to tack the boat every time.

Getting back to the slip under power was the hardest part - fortunately the marina is slightly sheltered by the dam wall.

What a boat!

I have a really strange idea that I would love to get your opinions on.
Almost all of the trailerable trimarans I’ve seen use a very narrow deep v shaped main hull. I assume that this design has evolved to minimize wetted area and to minimize leeway and to help windward performance. This design gives them good performance but it only leaves a very narrow hull for accommodations. And in the length that is reasonable for trailering (up to 26 feet) there just isn’t enough internal volume for comfortable accommodations. Has anybody experimented with a flat bottomed trimaran? It seems to me like a hard chined flat bottomed hull would hop up on a plane very quickly. It would be like lightning downwind and lee boards could be used to improve windward performance. If the main hull had an 8 foot beam (for legal trailering), This would give huge inside volume for accommodations. Sure it would pound over waves, and it would never be a blue water circumnavigator, but if it was built solidly it should do well in protected waters?? I know that Seapearl has a trimaran version of their 21 footer. I’d be really interested to know why no one else has tried this. I’m hoping to build a prototype soon, but first I’d really like to get opinions on why a flat bottom (with leeboards) wouldn’t work on a trimaran.

[yipster]

hello guest,
i recognise the thinking, i had the same. apart from hard chined flat, an 8 foot beam gets you into single hull wave resistance and hullspeed limits. offcourse when you can get it to plain...

yipster

[tspeer]

The V shaped hulls went out with the Pivers in the first generation of offshore multihulls in the 1960's! Today's multihulls either have rounded sections for minimum wetted area or flattened sections for more space and planing.

The Farrier designs definitely have planing sections with rounded bilges, and there's a definite difference offwind when the main hull starts planing - the boat just keeps going faster and faster.

This drawing shows the non-V shape of a Farrier design:

My experience with the F-9 (31' version) is that the flattish forefoot does pound a little bit when going upwind in a sizeable chop. I prefer the lines blended from, say around 30% Lwl to a more rounded shape at around 15% Lwl. That would preserve the planing run and cabin floorspace while easing the entry when the bow moves vertically down onto a wave.

I built a high powered planning hull tri in 1974 that would plane upwind and go like a bat out of hell off wind. The main hull was 20' LOA and about three feet wide; she weighed about 350lb all up.
She would plane upwind in about 8mph true.
Downside: she was slow in light air.
As a compromise for achieving interior room I think it is viable but you'd get a better ride in nasty stuff in a Farrier or similar design.

[Stephen Ditmore]

My understanding is that the wavemaking drag goes way up if the length to beam ratio goes below 10:1.

I guess it pretty much depends on whether the hull is a planning hull or not; most skiffs have beam to lengths below that and of course many multis are much higher. Bethwaite talks about the "humpless" hull that transitions more or less smoothly from displacement to planning speeds-at beam to length ratio's below 10/1....

Originally Posted by Thomas Rheuble

Hello: I am new to this site, but am impressed with what I am seeing here. I sail a WindRider17 in the Gulf of Mexico, and am looking to step up in size. The logical choice would be a Corsair or a Dragonfly. Is there anyone out there with experience with one? Thank You Thomas Rheuble Rheuble@aol.com

Also do consider the Catri boats, I am very happy with that choice !