Reply to :: Catamaran Sailboats at TheBeachcats.com

Welcome anonymous guest

Please Support
TheBeachcats.com

Forums index page

Reply to: H-18 hydrofoil

Message body

[quote=smfinley]I also have not had a mechanics class in over 10 years, but interesting how many engineers there are on this site : )  1473flyers, yes that was one issue I was hinting at.

Here is another,
In simple terms the torque from the crew and windward hull (against the leeward hull) will equal the 400+ lbs times the 8' beam of the boat right (3200 ft*lbs)?  The torque equation for the sails gets more complicated when the mast is connected in the middle of the crossbar and anchored to the windward hull.  I have had most of the leeward hull on a SC20 under water, and thinking the only way it got there is the force pushing down displacing the air volume of the hull.

Assume H18 hull was 18' long and averaged 1' wide and 2' tall (just my SWAG).  Half the volume of the hull would be 18 cubic feet.  Water is 62.5lbs/ft^3 so half full of water you would have 1123 lbs of water in the hull.  So if the hull was dry but half under water you have 1123 lbs of force pushing it down.  3/4 under water would be 1685 lbs.

I am sure the force comes from many different dynamics, but I think it will be much greater then your initial estimate.  Also think about the additional forces pushing the centerboards backwards when trying to lift the boat up while moving forward, there is a lot of drag forces in water.

This does sound like a great senior design project.  Always nice to have a project that is both educational and interesting at the same time.  Can't wait to hear how it goes, don't let us stop you, just wanting to make you think about every possibility.
[/quote]

No HTML tags allowed (except inside [code][/code] tags)