Atlantic 48 vs Switch 51

[Catastroff]

Hello everybody,

surfing the web i found some videos of atlantic 48 sailing at very good speed.
(also read a post from atlantic 48 owners mentionning high speed again.)
I have a switch 51, witch i think is a very good boat, but i never sail this fast, and i can tell that i am always a little bit overpowered with sails).

Reflexion is abought figures...
atlantic 48 is 9.8t empty / switch is 10t (mine as been weighted fully loaded at 13.4tons with all bluewater equipment)so the atlantic should come at around 12.5tons with same equipment)

main sail is 74 m2 for the atlantic and 78 m2 for the switch
genoa is 44 m2 for the atlantic and 50 for the switch


On a video you saw the atlantic sailing 90° app wind, 10knots app wind and boat speed is close to 9 knots...then with 20knots app wind speedo read 14.6 knot...(hope it is top speed !)

i do not remember exact speed my cat do in 10 knots of wind but it is far from 9 knots (maybe 7).
With full genoa, 1 reef, into 25/30kn aw and 90° i got around 11/12kn with top speed at 13/13.5..

I know that hulls design and weight difference explain everything...but so much a difference for quite same figures...
(set of sails as to be changed, but it is not a 1knot difference.

Would like to have your opinion on this, and if there are some switch 51 sailor around here...

[deckofficer]

I wish Chris White was a member here, he could explain the difference. All I know are his hull designs are efficient. He designed a hull for the power cat market, the Buzzards Bay 34, and it does 32 kt on close to the same power a PDQ 34 does 19 kt.

[Sand crab]

Where did you get the 9.8 light displacement number for the A48? The specs on this page aren't clear whether it's light or heavy disp. I also wonder if there is a confusion between metric tonnes and american tons. Anyway, I suspect the A48 has slimmer hulls than your Switch and that's why it will go faster. I am not sure that it can carry the 3.4 tons (tonnes?) gear that you can and still be a performance boat. I like your boat BTW and would rather have it then the A48. Did you buy Zia?
Specifications - Atlantic 48 Catamaran by Chris White Designs

[Catastroff]

hello sand crab,

You are right about payload...and no, i did not buy Zia, but Yakataka..! It is hull no 7, built 2002. I bought it second hand in may 2011. Very happy with it. Quite fast, very seaworthy, confortable and easy to sail. I plan to leave Turkey in 2014/2015 to go round the world.

[Caracal]

3.4 tonnes of "bluewater equipment"? For real?

[Sand crab]

Originally Posted by Caracal

3.4 tonnes of "bluewater equipment"? For real?

Not that unreasonable on a 51' cat. I guess that includes equipment, people and their stuff.

[Catastroff]

I took the displacement of a48 on chriswhite web page. It is around 22000lbs, wich is around 9.8 tons, if i am right.

[Caracal]

Originally Posted by Sand crab

Not that unreasonable on a 51' cat. I guess that includes equipment, people and their stuff.

He said "bluewater equipment". That's a lot of gear, even if he is carrying a full set of sails, a big battery bank and so on. It's a lot of extra weight. Especially on a multihull. 7500lbs on top of a multihull which weigs 22,000lbs is another third of weight in "gear" alone. It's the equivalent of carrying almost 47 people weighing in at 160 each.

It's no wonder it's not as fast as it could be with that extra load of a third of a boat.

[Sand crab]

On his brokerage page Chris lists all the boats as half displacement. Maybe that's the reason they are so fast. I do believe they are one of the lightest boats in their class.
Chris White Designs (S. Dartmouth, MA)

[Catastroff]

I am sure that i do not carry 3.4 tons of equipment. What i know is that boats in general are heavier under the crane that they are on the yards spec sheets. They built 16 switch 51, i am sure that each of them has got different wheight.

That's to say that mine is maybe 11 tons empty, who knows ? maybe the crane weight system is not very accurate...and also, it was weighted with full fuel.
(800 litres)

[belizesailor]

Originally Posted by Sand crab

..Did you buy Zia?

I know the owners of Zia...last I saw them (a couple of months ago ) they were in Rio Dulce.

Ive spent a very small amount of time aboard these two boats, so cant answer definitively, but my impression is that the A48 is more spartan and a bit more agressively performance oriented.

[Palarran]

Originally Posted by Sand crab

I like your boat BTW and would rather have it then the A48.

+1

Switch's look bad ass.

[Catastroff]

what you mean 'bad ass' ?

[Cotemar]

Originally Posted by Catastroff

what you mean 'bad ass' ?

Badass is (US, slang) Having extreme appearance, attitude, or behavior that is considered admirable.

[Sand crab]

+1 on the badass. But to be fair the A48 is even more badass. I'm just not a fan of the cockpit forward idea. Switch=Ferrari 360 A48=Lamborghini Countach