Does a catamaran plane?

Generosity (of the participants of the thread) brought it back

"If it is not a cat then it is a dog"...... meoooouw

 

I think hulls can be crudely categorised into 5 descriptions:

Displacement,
Semi-planing,
Planing,
Foil Assisted,
Foil Flown

I would call most modern cats with square sterns....semi-planing hulls. The stern provides lift but I'm guessing that the aspect ratio is too slender for efficient planing. I think Phil said it well.

I like cats that are designed for full displacement, because light air is a problem for cats (wetted surface). I want as much speed as possible when the hulls are providing no lift. Any cat (displacement or semi-planing) will go fast enough for me in strong wind.

 

Good to see the age-old rivalry between Chris and Doug still exists

 

one more sprung to mind - "sinking" (or equipped with more lead and other ballast to supply the projectile needs for a small war)

 

Nice to have your here as well, Richard.

That ripple in your vision is me moving back into full cloaking posture.

 

Oh no... not again .....

 

Yeah, again.... what? Are we not allowed to ask questions here?

 

Fanie, & Heinz that type of discussion has been raging for the past couple of months with all our local experts contributing - I think there is general exhaustion in that group...- - Perhaps one will be so kind as to link you to those threads. Quite a lot of technical stuff that involved number crunching and jargon which I had no desire to learn, so took most at face value... A jolly good read...

Fanie, for displacement form, the images I posted from Robin Chamberlin - http://www.boatdesign.net/gallery/showphoto.php/photo/9662/ppuser/22903/sl/m - and John Hitch were displacement hulls (20 to 32 waterline length:beam ratios)... In the powercat format the stern end usually looks a bit like Robin Chamberlins C10 or my original "lets see the concept" masalai model - the propeller can be fully protected and uses a horizontal shaft. - the variation I liked was that held the thrust bearing, and the engine (weight) could be moved nearer midships and linked by a dual cv jointed hollow shaft like you would expect on a car.... sort of...
This lets the engine be softer mounted (less vibration and noise)...

Maintenance free electrical engines with the generators placed where they can be easily removed and accessed for servicing / repair is another option as the skinny hulls are more easily driven...

The solar/generator/electric drive system is starting to look interesting, 18panels of photovoltaic panels can deliver 3000 watts plus , 2 units of gensets - http://www.polarpowerinc.com/products/generators/marine_genset_lomb.htm - 700cc diesels can deliver a bit more than 9kw each - so that is up to 21kw of immediate power, plus what has been saved in the main batteries. - http://www.cruisersforum.com/forums/f126/green-motion-retractable-propulsion-generation-10261.html - that should get my latest hull nicely cruising.... metaphorically - add a good beam on breeze and quiet swell - http://www.boatdesign.net/forums/showthread.php?t=21274&page=2 - (see post 21) and with a pair of genoa up, I would give Pericles ? gunboat 60 a surprise.... I wish...

 

Yeah but posting a link would be helpful, who's gunna do that? I mean seriously, pissing competitions are sooooo much more fun, are they not? BTW mines bigger than yours

 

Give this old fart a break, that is why I asked if one of the "big-time" guys would - total recall is not totally recalling, bloody 0100101 remnant 0100101001 windows 0101010010 stuff ..1000101001010010100101010 Hic - still cannot recall... please help with a link you experts.....

Happy now sir?

 

Wasn't talking bout U silly No need to go red and yell!

I can't see it on searching....

 

I was only making it obvious for the experts to see in scanning thru optically, not search and who is yelling? all lower case except to be polite and define the beginning of a sentence... maybe - go through my threads and look for a serious and possibly relevant title - I think I posted once or twice...

 

Hello everyone,

This is J's assistant. He sent a deep space message and wanted me to post it here.

http://www.boatdesign.net/forums/showthread.php?t=14047

He said to tell everyone not to piss too much and to tell Meanz Beanz that he wishes it was.

Thanks
J assistant

 

Thks J



My lance is huge!

 

Jousting- it should come back to fashion- on skate boards. All the best from Jeff.