Author Topic: GA 28 built by Kachemak Skiffs Wasilla, AK  (Read 41598 times)

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json

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Re: GA 28 built by Kachemak Skiffs Wasilla, AK
« Reply #225 on: August 01, 2022, 02:06:56 PM »
Great real world info Dan, thanks for posting. I have been wondering for a while about the trim tabs, sounds like it's a good addition. What size tabs did you install?

Grady300

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Re: GA 28 built by Kachemak Skiffs Wasilla, AK
« Reply #226 on: August 02, 2022, 10:03:49 AM »
Great real world info Dan, thanks for posting. I have been wondering for a while about the trim tabs, sounds like it's a good addition. What size tabs did you install?
All great info. personally I decided to wait on the trim tabs to see how the hull operated with-out. Both my larger offshore factory fiberglass boats needed the trim tabs. So far I'm glad I waited on adding that option, my Kodiak doesn't seem to need them she runs great as is. Careful loading does help but to be honest I don't pay much attention to it.
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Brian.Dixon

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Re: GA 28 built by Kachemak Skiffs Wasilla, AK
« Reply #227 on: August 02, 2022, 10:37:29 AM »
Yes, and regards to being 'tender', keep in mind that there are two types of heeling stability.  The first is "initial stability" and refers to the first 6 to 10 degrees of heel or so - you want lower stability in this range.  It allows moderate and light waters to go up and down the sides of the boat (when not on plane) without making the boat heel.  Too stiff in this range is harder on both structure and people - snap rolling on every little wave gets tiresome.  The second form of stability ranges from where initial stability ends and increases in stiffness with more degrees of heel.  This is your safety margin that does make the boat heel with the water - to prevent larger water from coming in over the sides.  The Transverse Metacentric Height (GMt), the technical measurement of stiffness, is actually a little on the high side for this boat, so no worries there.  That said, the GMt lowers as the boat is loaded to higher displacements, which means a boat loaded heavy for a long trip and/or has hundreds of pounds of ice in it, will heel slightly easier from weights (people) moving around in the boat and will heel less as various seas climb up the sides of the boat (when off plane).

Oh, and most GAs do not use trim tabs ... just an FYI.  Everyone's boat tends to be loaded differently, though, so it could be that some benefit from them...
« Last Edit: August 02, 2022, 10:40:48 AM by Brian.Dixon »
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