New Tandem Cat Design launched in St. Croix, US Virgin Islands...

US Virgin Islands St. Croix's 'Gold Coast Yachts' just launched a new "cat" model, designed / built to run between St. Thomas and St.Croix, in the US Virgin Islands in the near future (Summer 2016).
Some details:
Length: 103'
Width: 17' 6"
Draft: 2' 9"
Cruise Speed: 20 kts
Max Speed: 24 kts

http://stcroixsource.com/content/news/local-news/2016/05/07/stx-ferry-hits-sea-next-week

 

i dont know much about boats, but i wouldn't get in that thing, it looks unsafe to me. can someone tell me why they made basicly 4 hulls instead of having two long ones?

 

What can one say? The "boat" was designed by a person who is locally best known as a Hedge-Fund Manager, a former VI Gubernational candidate and a Boutique Sports Car Manufacturer...

 

Anything that can smooth out the ride down there is a plus.

Gold Coast Yachts have pioneered a lot of innovative designs and processes and I doubt they would put their name on something without having thoroughly ciphered out all the problems.

I'd probably pay more for a twenty minute flight than a two hour boat trip though.

 

It almost seems like a pentamaran where the central hull has been nixed.

 

For ferry boats maximizing displacement is typically a top priority. I'm a bit surprised he didn't run the twin hulls the full length of the boat. So long as their shape was optimized it arguably would have been a more sound design with full length hulls. Additinal features I would have added would have been multiple chambers within the hulls to add extra buoyancy in case of a hull breach.

It's different though and that's obviously his statement. I wouldn't hop on board unless a) the owner never overloaded it and b) the operating area was suitable.

 

It looks like the 4 hulls are similar, so maybe one smaller mould with modification could be used 4 times. The cabin is essentially a box section and should have great torsional stiffness; note the circular windows of moderate proportions situated halfway up the box. It looks rather a clever design to me. Of course the devil is in the detail and so that doesn't mean it can't come a cropper. It will be interesting to see how it performs through the sea, but as its effectively a long wheelbase vehicle it might give the passengers a more steady ride in reasonable sea conditions.
Questions.
What is the waterline length? Front to back of the whole thing or the sum of the parts? And clearly it can't tilt upwards to plane else the front hull will be out of the water, but with the right underwater shape could it lift up, hydofoil like and parallel to the sea and get a shift on?

 

The forward hulls are Not the same as the rears. Look closely!

 

The four hulls are to make the ride smoother. Read all about it in the first column of the first page in the newspaper article that HueyCat posted in post #3.

Read about the different sized hulls in the article posted in post #1.

 

As a US vessel taking passengers for hire this is USCG approved and inspected. This includes structural integrity and stability as well as safety features like passive fire protection.

It is safe.

Like SamSam said, Gold Coast has built lots of "out of the box" vessels and did a lot of pioneering on wave piercing ferries as well. Their "bread and butter" are passenger carrying day charter sailing and power catamarans and they are very well versed in multihull and composite construction.

Way cool to see out of the box thinking hitting the water

 

I said similar.Look closely

 

Any news on how this is performing now its been in use a while?

 

Some more info about her on her Builder's website :

http://goldcoastyachts.com/Commercial-Power/CP-transport/GC103TC/GC103TC-features.pdf

With photos of her under construction :
http://goldcoastyachts.com/under_construction.htm

Rurudyne mentioned Pentamarans - I think the original concept design for these was with Nigel Gee in England
http://www.bmtng.com/media/60157/Paper50-ThePentamaranFastFerry....pdf

 

The ferry has been running for a while and I hear that the passengers rarely get sea-sick, the sober ones.
One reason is that the vertical motion frequency of the tandem-cat remains close to its natural frequency, irrespective of the encounter frequency. The frequency of 'zero-wheelbase' hulls however is highly dependent on the encounter frequency. Motion sickness mostly occurs at 0.1-0.5 HZ, and the tandem cat's natural frequency is higher than that.

 

Passengers laud ferry between St. Croix and St. Thomas http://www.virginislandsdailynews.com/news/passengers-laud-ferry-between-st-croix-and-st-thomas/article_829c4b99-c3b6-539f-a886-42d496e4383f.html


New Inter-Island Ferry Unveiled - St. Croix Virgin Islands Real Estate http://www.chrishanley.com/news-info/new-inter-island-ferry-unveiled/


QE IV Ferry http://www.qe4ferry.com/

Very interesting.