The faster we go, the less we consume

[ZipTie]

A2V catamaran breaks 45 knot barrier

“The faster we go, the less we consume”. The French company Advanced Aerodynamic Vessels (A2V) unveiled a stunningly unique catamaran in La Rochelle, France. During one of our visits we discovered the yacht being tested. It is a boat designed by famed designer Marc Lombard and is a prototype for an innovative concept of ultra-fast vessel aerodynamic lift. The composite catamaran with futuristic lines, was designed and built in great secrecy over a period of 18 months. Made of advanced plastics, this first model measures about 33’ and at 3 tons can reach speeds of 45 knots with only two Mercury 200hp outboards.

The basic idea stems from the fact that there are currently no commercial ships that can reach speeds of over 40 knots profitably.

Maybe this new A2V concept is the beginning of something revolutionary- especially if we realize that most of the world’s freight is transported by ships.

HOME - Advanced Aerodynamic Vessels

[valhalla360]

Looks like a Ground Effect Vehicle. They have been around for decades but never really took off (pun?)

When a plane is at altitude, there is so much air under the wing that the air can simply move out from under the wing. To get enough lift, they have to go very fast to compensate.

At very low altitudes, the air gets trapped between the wing and the ground limiting it's ability to move out from under the wing. This results in higher air pressure under the wing, so you can use a combination of smaller wing and lower speeds to achieve sufficent lift.

The only slightly unusual thing about this is they use a propeller in the water rather than in the air. While most GEV can come completely clear of the water, this one will eventually reach a limit when the props start coming out of the water.

I expect there is some truth to the efficency as the faster they go the more the hulls come out of the water...but I suspect this is based on smooth water. If there is significant wave action, it won't get the same ground effect and the hulls will keep hitting wave fronts. A GEV that uses a jet or airplane propeller would have an advantage as they can get the hulls completely out of the water and literally fly just above most modest waves.

I don't buy the freight market tag as they would be very weight sensitive similar to aircraft. I could possibly see them competing against hydrofoil passenger ferry designs that use a similar effect of lifting the hulls almost completely clear of the water.

[arsenelupiga]

computers at work here, simulating 3d object behaviour in moving fluids - water & air.

unexpected results that clash with mainstream thinking will come out for sure.

[unclemack]

10 metres, 3 tons, 400hp, 45 knots, made from lightweight composites?

MSC "Manannan" is 96 metres, 5743 tons, 28800kW, 40-42 knots fully laden. Construction unknown to me, built 1998, one of six I believe.
Passengers & crew 850, vehicles 200.

400hp is about 300kW so 100kW/ton approx.

28800/5743 = 5kW/ton approx.

Somebody check my sums please...

I get the differences in scale and that the new craft is experimental.
For all I know it might turn out to be the future of high speed craft but so far I don't see it as a huge leap forward.

Manannan, already scaled up and in service is presumably commercially viable or the Steam Packet would have dumped it?
Been thinking about sailing on her this year, just for the experience.

[yotpop]

I can see what's missing: an outboard bracket and a get-you-home 5hp

[Don C L]

45 knots in any kind of swell? I think not. Why not just bring back the Spruce Goose and fly in ground effect? I bet that would be fairly economical.

https://www.youtube.com/watch?v=x7vW...qkDZkZN3MS9B7Q

https://www.youtube.com/watch?v=rv1PV9S6cmc

A lot cheaper than a bullet train!

[s/v Jedi]

Here's a bigger one:
http://youtu.be/V8Nu94khHoo

[44'cruisingcat]

John Hitch did it years ago. Fourth boat down:


Multihull Sailing Vessels For Sale

[a64pilot]

Yes, the Caspian Sea Monster


Sent from my iPad Pro using Cruisers Sailing Forum

[Don C L]

OK, can ANYONE tell me how this boat designed by John Hitch sails? I have never seen a design like this... and I confess I am very skeptical that it is a good sailing design...