Movie Moana - Disney

I saw this cartoon called Moana. The youtube add is below.

https://youtu.be/LKFuXETZUsI

It has some interesting design concepts for Polynesian catamarans. I like the sails.

 

Isn't artistic license wonderful . . .

 

my sail interest.

A primary interest was the sail design. There was a lanteen sail and it was rigged for a oneway journey. It is a tradewind rig. It was so huge. It was a go-east rig. To make it go west it needed adjustment like moving the mast to the other hull. If the wind gets unfavorable it would just be dropped like a squarerigger and time to wait for the goddess Pele to be nice again.

 

that is a proa, not a catamaran, and it has a crab claw sail, not lateen. clearly by the toon action the cartoonists just copied pictures and do not know how they sail.

This is a south pacific mythology, not an attempt at historical accuracy. Disney has done the same in Frozen, Hercules, etc. Actually some pretty nice graphics, but the classic stories are somewhat altered (usually extensively).

I would not put too much credence in the cartoon, but if you google "crab claw sail" you will likely find real videos of them in action.

 

Agreed, it was a crab claw and the last thing you want in the trades is a huge rig, with the majority of area placed as high up as you can get it. Also agreed in that the artists did a good job, making things look like they work, but the reality is it's all fantisity.

 

The curious thing about the Crab Claw rig is there seems to have been two different types.

One was for shunting and one was for tacking

The shunting one is the one which seems most familiar.

The tacking one, which was used on both single outriggers and voyaging double canoes, had a lot in comon with the Bermuda Rig. This stands to reason as both have similarities to the Lateen rig.

The tacking version of the Crab Claw appears to have had only two spars, a Mast and a Boom, just like the Bermuda Rig.The difference was how the second spar was orientated.

With the Bermuda Rig, the second spar was more or less parallel to the WL, and it framed the shortest side of the triangle, which made up the sail (which often wasn't much shorter than the mast side).

With the 'Tacking' Crab Claw, the Boom was canted up consideably, often more than 45 degrees up from horizontal, so it mostly made up the Leech of the sail. Often this Boom was curved, so the only open fabric of this sail ended up on top. Even when it didn't, the two longer sides of the triangle were taken up by the Boom and the Mast, leaving the shorter one for the 'Leach', which was more along the top of the sail than along its trailing edge.

The Mast was not a Mast, in the conventional Western sense, but was more like a Yard which connected to the Deck. It was often propped up with some sort of strut. The 'Mast' apparently could be tilted fore and aft, while under sail.

I think a lot of the legend of its superior drive per SA comes from three facts:

1.) Its Center of Area (CA) is considerably higher than that of a more conventional sail, so most of its SA is where most of the wind is,
2.) because the 'Mast' and the 'Boom" take up the longer sides of the triangle, there is not much opportunity for the sail to twist, and
3.) because the 'Boom' is cocked up so high and is so long, the belly of the sail forms more between the 'Mast' and the 'Boom' than on the un-supported edge. This keeps a nice consistant curve up most of the sail, without high strength sail cloth and other typically modern sail technology. Since this rig had no Halyard, the upper ends of both spars could be made quite tapered. This could have allowed fabric to be made with curved edges, providing most of the advantages of a Bermuda Rig with bendy spars. Most famous of which is the sail tends to flatten under strong winds, and belly under light ones, just from the tension of the sheet lines.

The problem is there is no way to reef the bloody thing.

It appears that the south sea islanders expected to paddle a lot during their voyages, so in the case of the double canoes at least, the SA may have been quite modest in proportion to the displacement, with S/Ds maybe in the low teens or even in the high single digits.

This would be an interesting rig to try on a motor sailor. It would have the most drive per SA, and the Boom would be canted so high up, it wouldn't menace to people and structures, such as high deck houses.

I wouldn't have the whole rig disappeare, like the example shown in "Sail" magazine, but would have a furling line, which would pull the Clew end of the Boom to the top of the Mast. In between, there would be a series of braille lines, to constrain the fabric.

 

Can someone explain where artistic licence has been taken please?

 

Petros, I think the big boat was the catamaran being referenced. Not the small proa.