Trim Tabs

[rik_elliott]

http://marinedirect.co.uk/images/trem_wheels6_lg.jpg
doesn't this show fixed trim tabs too? honwave owners will recognise the transom (and the annoying transom wheels). only, never and always are dangerous words ;-)
not tried smart tabs myself, but a good friend has and found them excellent on a 5.5m fast fishing boat. i really want a set. dole fins are cheaper though, but probably lack the lateral stabilising effect.

[gotchiguy]

Originally Posted by Nos4r2

Those aren't smart tabs.

I realise that. Sorry, I meant to say that is the only type of craft with fixed tabs that I personally have used. Which is why I agreed with you that my comments were essentially an extrapolation of my experiences with other systems.

I would imagine that the Honwave airdeck extension thingy would have much the same effect as fixed solid tabs as I showed above and have used. However, the hull extension business further up, I couldn't comment, although I have seen Zeppelin craft before with similar things.

[captnjack]

The hull extensions provide no stern lift. Smart tabs or better yet operator controlled trim tabs provide stern lift. IMHO they really only make a lumpy sea feel less lumpy if you are otherwise riding so bow high that the flatter portions of the mid-section of your hull are slamming into the waves. The effect will all depend on your deadrise.

[longjohn]

Originally Posted by captnjack

My ali hull has what are essentially fixed trim tabs, could also be called a hull plate extension. Visible here with the transducer attached on an extra piece of "L" shaped aluminum.

Lots of the newer Avon/Zodiac hulls have the glass fibre equivalent of those hull extensions and the airfloor Honwave sibs have them as well.

For smaller boats isn't fitting hydrofoils instead of trim tabs going to achieve much the same effect, at far cheaper cost and essentially automatic operation via engine trim? Speaking of which I was on a 6m ish hard boat recently and it had its trim tabs linked to engine trim so again more or less automatic operation. Seems to me it could get very complicated manually trimming engine and tabs indepedantly needing an extra pair of hands.

[Cookee]

Originally Posted by nik

I was wondering if they would make a 5 to 6 metre boat perform better or give a smoother ride in lumpy water like you get in the solent.
Adjustable tabs, about £400 to £500?

Trim tabs help in two situations, firstly getting on the plane and running into the wind and waves they help keep the bow down and secondly when there is a side wind they can keep a boat from tipping into the wind - obviously this would only work with non automatic tabs.

To answer your question if your boat is running with the bow flying up in the air when running into the wind and trimmed in then tabs would help but I wouldn't expect tabs to perform miracles.