Drift, stern downwind

[jackster]

i highlighted copied and pasted into google search this url
http://www.yamaha-motor.jp/marine/index.html
and then clicked translate in results to get a "kind" of english

it seems this is their chosen way to drift fish and keep the bow into the wind

i put out a drogue to keep the bow to the weather on a drift, but this has me intrigued
has anyone ever seen or used a twin rear sail arrangement like this
adjustment seems to be on how far apart you spread the 2 booms and sails

the sails create 'adjustable' drag, there is no drive with them
they have gone to a lot of trouble to create this set up, must be something in it


http://www.yamaha-motor.jp/marine/lineup/boat/fishingboat/fast-26/technology/img/pic_005.jpghttp://www.yamaha-motor.jp/marine/lineup/boat/fishingboat/fast-26/technology/img/pic_006.jpg

http://www.yamaha-motor.jp/marine/lineup/boat/fishingboat/fast-26/technology/img/pic_007.jpghttp://www.yamaha-motor.jp/marine/lineup/boat/fishingboat/fast-26/technology/img/pic_008.jpg

http://www.yamaha-motor.jp/marine/lineup/boat/fishingboat/fast-26/technology/img/pic_009.jpghttp://www.yamaha-motor.jp/marine/lineup/boat/fishingboat/fast-26/technology/img/pic_010.jpg

http://i77.photobucket.com/albums/j67/webfishingclub-/2b.jpg

it is used on large craft too

http://www.yamaha-motor.jp/marine/lineup/pro-fish/angling/dy-160/img/pic_001.jpg

[Blackened]

G'day
Interesting concept, i've never heard or seen anything like it.

The last picture by the sail shape looks as though they've taken inspiration from a chinese "junk" ;)

Come to think about it, you do see the odd coastal cruiser with a sail attached to help stop rolling in the open ocean, so you only have the pitching effect.

Dave

[Roughasguts]

Cool ahh, acts like an aircraft, symetrical aerofoil on the fin.
Makes it weather cock, but works a bit better cause of the camber of it.

[TOPAZ]

Interesting concept - the sail is acting as a weather-vane, and making the vessel drift bow to wind instead of broadside. The only disadavantage would be an increased rate of drift compared with using a sea-anchor.
It would also be possible, by adjusting the angle of the sail, to cause the vessel to drift on an angle, which may be an advantage when fishing.

[Kerry]

It would appear to basically follow the polynesian catamaran steering principle of using different depth dagger boards, in this case inverted and uses the wind.

A Cat is very controllable drifting using the trim/tilt individually on each outboard as well as the steering angle. With practice you can basically drift a cat through about 225 degrees from quartering the port bow to starboard bow.

[Roughasguts]

Just guessing but I think it would only work well on a keel boat.
Something like me cab boat with an outboard hanging off the back,
dragging the arse down.
Ain't going to work, with a light large surface area up front.

Any wind is still likely to push the front around, way before the sail has any effect.

[jackster]

someone said they saw them on jap squid boats

the 2 sails forming a v for wind drag
was new system to me too

must have advantage over drogue, its a lot of work to go to

[Mr__Bean]

They would be much quicker to operate with if you are drifting over smaller reefs or wrecks.

You just start up and drive back to your starting point rather than having to pull in the drogue each time.

Other than that, why bother?

- Darren