Hydrofoils -vs- Trim Tabs

[fish-n-dive]

Discounting balancing a boat, which would you prefer and why??

I voted Trim Tabs

[Spaniard_King]

I suspect you will get those that have had foils and not tabs and vice versa.. Personally the tabs trim the boat way more to the conditions with the benefit of triming the boat properly when runing side on to the wind

[Chimo]

They both add a bit of lift.

Hydrofoil is cheap and easy to try and does help

Tabs add lift too and also allow best use of a deep vee to soften the ride in chop.
Tabs like most with a plate activited by a ram or electric motor (which I have) dont slow the boat and use more fuel which the other type do. See Peter Websters report after he fitted the Q type to his tinny

I fitted my bits one at a time to get to know what each did before adding the next and they both added / improved the boat's performance and the ability to optimize ride and enjoyment. Much lower planning speeds can also be achieved which is great in choppy conditions.

So there you go, I vote both but not the Q type tab and I'll just have to hold the fish further back till they get netted or gaffed.

Cheers
Chimo

[finding_time]

Mate it's a no brainer on a 6m+ boat! Tabs !!!! They both get the boat up quick but to balance the boat you'll need tabs,they'll make that new boat of yours MUCH MUCH better if you use them properly!


ian

Just had to edit that post as what i wrote late last night made no sense! Better now!

[snorton]

I love my Permatrim!!

[Noelm]

tabs are the ONLY device in this poll that will have an effect on Boat "balance" a foil will NOT make a Boat run flat in a side on Sea/Wind, remember if the Motor is fitted correctly, the foil is out of the water at planing speeds, so will have half of bugger all influence on keeping the Boat level, not too sure how you could even contemplate comparing the two devices!

[TheRealAndy]

tabs are the ONLY device in this poll that will have an effect on Boat "balance" a foil will NOT make a Boat run flat in a side on Sea/Wind, remember if the Motor is fitted correctly, the foil is out of the water at planing speeds, so will have half of bugger all influence on keeping the Boat level, not too sure how you could even contemplate comparing the two devices!

I have often wondered about foils on the plane. My boat has one that is angled up, and in my opinion i doubted it would do anything. One day I will remove it and see what happens. Maybe it helps get it on the plane.. Either way, if the boat did not come with it I would have probably never fitted one.

[TOPAZ]

It depends on the hull - I have both on my Whittley Cruiser 660, as we run it heavily loaded for cruising, and it needs the extra lift provided by the Sports 300 Foil that I have fitted - the Mercruiser sterndrive does not have the range of trim that I would like. I also have electric trim tabs for lateral ride adjustment.
NOTE: the instructions for my trim tabs specifically state to NOT use them for added lift at the stern - only for lateral adjustment. The instructions say to use trim/tilt for stern lift. (They are Barrett tabs).

Richard

[Noelm]

correct Topaz, the two devices are NOT used for the same purpose, indeed I personaly doubt any benefit in those foil things at all, but some say they work, so I guess on some rigs, they provide either a perceived benefit, or maybe even some measurable advantage.

[julian1]

Trim Tabs, as stated there is no comparision for balance or side on trim. Plus you can adjust accordingly to the sea state, ie cross wind, down wind, headon etc.

cheer's

Julian

[TOPAZ]

correct Topaz, the two devices are NOT used for the same purpose, indeed I personaly doubt any benefit in those foil things at all, but some say they work, so I guess on some rigs, they provide either a perceived benefit, or maybe even some measurable advantage.

Noelm - My history with 'hydrofoils' goes back to my previous boat, a 5.2metre Swiftcraft SeaHawk MkII, with a 115HP v4 Evinrude 2 stroke.
For 10 years I was involved with the Red Cross Murray Marathon safety boats, where we would escort the canoe fleet down the river, with supplies for 5 days, crew of FOUR (Skipper,navigator,radio operator & first-aider), which made the boat very stern heavy.
The river is well known for many snags, and the foil was fitted to allow us to get up on the plane more quickly, and at a lower speed , which then resulted in the boat drawing 30cm or so less water, therefore hitting less snags.
You might suggest that going very slowly would result in less likelihood of snagging, but the distances we had to travel and the time we had to travel them in, meant that we HAD to travel at planing speed for most of the time.
With the foil (in that case a Tiger Shark VG) hitting snags was less likely, and, if unavoidable, done at a much lower speed. (It still gives you a hell of a shock though, even when you know that a likelihood exists),
I carried over the foil fitment onto my new Whittley, as a result of my good experience with the Swiftcraft, but this time fitted the Sports 300 instead, which works more or less like a Permatrim, rather that a hydrofoil (eg Tiger Shark)
Another story - a mate has a Streaker 5.2metre half cab, which he also uses for cruising (stern heavy, etc), and he recently had to replace his 30-year old 115HP Evinrude 2 stroke. The biggest problem he faced with new motors (he wanted either 4-stroke or injected 2-stroke for economy) was their weight when compared with the old Evinrude. He finally decided on a 115HP Evinrude Etec, which he finds terrific, BUT he had to fit a Permatrim to counteract the increased weight at the stern (some 20+ kilos, or over 40lbs)

I think they do have a legitimate place in some circumstances such as I have outlined above.

Richard.

[Getout]

In my experience, a foil is a big help on a shallow-vee hull, because the leg is not very deep in the water and the prop is prone to ventilation. In this case, a foil reduces the sucking of air onto a cavitating prop (by blocking the path of air) in sharp turns. It gives more trim control on a light hull.
Tabs work well on a deep-vee hull cause it is more prone to lean from wind effects. Ventilation is not so much of a problem because the prop is deeper in the water on turns so I don't reckon a foil is as much help on a deep Vee hull (especially since most deep vee hulls are heavier)

[Chimo]

Getout

Foils are useful on deep vees too. Foils on my Seafarer vagabond lifted the bum maybe a couple of inches and did allow it to plane at a slower speed.

Also I need to address the comment about tabs not being of use to lift the bum of a boat and not being able (according to the instructions) to be used for this purpose. I have to say that even when mine are fully up ie not in use they do aid bum lift probably due to fact that they actually extend the hull length and hence do provide lift.

Cheers
Chimo

[ashleyhj74]

I've gotta permatrim on my spearfish 21, wouldnt own a boat without one, but thats just me, many would disagree with that i'm sure. The only reason i want tabs is for side to side movement.

[Getout]

Getout

Foils are useful on deep vees too. Foils on my Seafarer vagabond lifted the bum maybe a couple of inches and did allow it to plane at a slower speed.

Also I need to address the comment about tabs not being of use to lift the bum of a boat and not being able (according to the instructions) to be used for this purpose. I have to say that even when mine are fully up ie not in use they do aid bum lift probably due to fact that they actually extend the hull length and hence do provide lift.

Cheers
Chimo
I agree that tabs lift the bum, so a foil is less necessary if you already have tabs (if bum lift is the objective)

[ozscott]

I have had both on several boats and the hydofoils on some boats def' help lift and so on but overall you just cannot beat leaving the leg as the manufacturer intended and adding adjustable trim tabs.

Cheers

[scrubba01]

I have the QL trim Tabs they do a great job of leveling the ride of the boat both side to side and front to back. When going into the chop they really make it cut through a lot better giving a smoother ride. The design of these are much better as they are fast acting, look neat, nothing to get caught on or for swimmers to step on cut themselves on and you don't have to think about them when going in reverse as with the hydraulic tabs which can force the back of the boat down in reverse. As the plate which adds the lift only goes into the water a total of 25 mm it uses little more fuel compared to the surface area and the amount the other tabs have to be put in the water to create lift.

I know it sounds like I am trying to sell them but I believe they are that good as for the foil it would be obsolete with tabs fitted. IMO