Trim tabs- why no factory option or standard?

[Mariah180]

I've read all the reviews and understand the physics behind why and how trim tabs work. But what puzzles me is that there are at least a dozen high end modern boat hull designers and none of them (that I know of) sell as a factory install or dealer option the trim tabs. 20k for a modern 18' boat and the manufactor isn't smart enough to install or fabricate 100.00 trim tabs? What gives?

I know that one boat has the extended Vplane hull design. But I can't recall ever seeing trim tabs on any cobalt, searay, crownline, Mariah, four winns....

Is there some type of danger or regulation that prevent a factory install?

 

[mpsyamaha]

Re: Trim tabs- why no factory option or standard?

i think once you get over 20ft boats the trim tabs become more common. for instance, the company i work for owns three 24' searay sundecks and they all have factory installed bennett trim tabs on them.

 

[JimS123]

Re: Trim tabs- why no factory option or standard?

In the old days wooden boats in this size catagory simply didn't need them. I own a 58 year old woodie with stern mounted tanks, battery and even the steering console is aft mounted. Yet, it come up on plane perfectly level with no bow rise.

One of the reasons that boats need them today is the fact that motors are generally bigger and heavier than they used to be. There are a few boats out there that perform adequately, but they are few and far between. Today boats are for the most part designed to look pretty. Ergonomics and functionality have been lost as well.

To answer the OP's question, they aren't included as options because that would be admiting that the the hull design is not all that it should be.

 

[45Auto]

Re: Trim tabs- why no factory option or standard?

Actually, they are included as options on every mid-size boat I know of, and as factory equipment on larger boats. Has nothing to do with hull design fantasies, it's all about price.

Trim tabs on boats perform the same function as flaps on airplanes. It's all about fluid dynamics. Just like there's no way to optimize an airplane wing for both low and high speed operation, there's no way to optimize a planing hull for both low and high speed operation. The tabs, like flaps, provide added lift at low speeds but are retracted at high speeds to eliminate drag.

I believe most people don't want to pay the factory prices for the option. For example, they were a $615 option on my 2003 22' Crownline, $1115 if you wanted the indicator (and the original owner didn't get them). Kind of like paying $1000 for a factory high-end stereo on a new car when you can go to Best Buy and get something twice as good for 1/4 the price.

They're an $831 option (hydraulic or electric) on 2010 23' Stingrays:

http://www.stingrayboats.com/products/models10/models.php?model=230SX&action=2

 

[Mariah180]

Re: Trim tabs- why no factory option or standard?

Great info, thanks!

Going to put a set on my little 18'. Just wanted to ask before holes get drilled,

 

[DBreskin]

Re: Trim tabs- why no factory option or standard?

Trim tabs on boats perform the same function as flaps on airplanes. It's all about fluid dynamics. Just like there's no way to optimize an airplane wing for both low and high speed operation, there's no way to optimize a planing hull for both low and high speed operation. The tabs, like flaps, provide added lift at low speeds but are retracted at high speeds to eliminate drag.

Great explanation!

 

[H20Rat]

Re: Trim tabs- why no factory option or standard?

the biggest reason probably isn't even cost. On an I/O (or outboard), their use is somewhat limited anyway. You have trim on the drive, no need for a second for MOST cases.

On ski/wakeboard boats, trim tabs ARE generally default options.

 

[haulnazz15]

Re: Trim tabs- why no factory option or standard?

Trim tabs on boats perform the same function as flaps on airplanes.

Funny, I've never used my flaps to aid in planing out/weight distribution. I normally use them to increase my rate of decent while maintaining the same speed.

 

[642mx]

Re: Trim tabs- why no factory option or standard?

The tabs, like flaps, provide added lift at low speeds but are retracted at high speeds to eliminate drag.

Some of us drop the tabs at high speeds too. I use them to help gain control at high speeds. Rarely do I ever use them at low speeds (unless I'm in real rough water).


For the OPer... It depends on where your at. Around here, most people use their boats on the river. Its rarely rough, so you don't find too many tabs on the showroom floor boats. But if you go to a marina around a big lake (like Kentucky Lake for example) almost every boat has them because of the rough water conditions.

 

[skargo]

Re: Trim tabs- why no factory option or standard?

the biggest reason probably isn't even cost. On an I/O (or outboard), their use is somewhat limited anyway. You have trim on the drive, no need for a second for MOST cases.

On ski/wakeboard boats, trim tabs ARE generally default options.

I would disagree, to an extent, since you can't trim side to side with your drive, and with my tabs full down and my drive full in, vs. drive full in only it's a big difference. that's on my I/O.

 

[JimS123]

Re: Trim tabs- why no factory option or standard?

Surely tabs are optional on larger boats and have been for years. Even Stingray recognizes that on their 23 footer.

But the OP was talking about a little 18 footer. Maybe some company offers them on the little trailer boats, but you won't find many.

My point was that 18' boats didn't used to need them.

 

[45Auto]

Re: Trim tabs- why no factory option or standard?

My point was that 18' boats didn't used to need them.

18' boats used to "need" them more than they do now. Difference was that performance expectations were much lower, so people were happy with the status quo in performance (low) which was all they knew. Wooden boats from the 50's may look "retro" and cool to some, just like some people like '57 Chevies. But compared to modern technology, they're extremely low performance and high maintenance.

Modern hull designs outperform older ones in every way imaginable. Lighter, longer lasting, better low speed and high speed performance, better materials, more interior space, better ergonomics, more power, and relatively cheaper. What more do you want?

 

[haulnazz15]

Re: Trim tabs- why no factory option or standard?

People have gotten fatter since the 60's, so now you need more running surface to plane out on a 18' boat, lol.

 

[Pirate_40]

Re: Trim tabs- why no factory option or standard?

People have gotten fatter since the 60's, so now you need more running surface to plane out on a 18' boat, lol.

Lol. put three fat people on one side of the boat while under way. You'll wish you had tabs.

 

[45Auto]

Re: Trim tabs- why no factory option or standard?

Lol. put three fat people on one side of the boat while under way. You'll wish you had tabs.

Old wooden boats never had problems with this because they wouldn't float or run long enough for anyone to notice it was a problem!

 

[JimS123]

Re: Trim tabs- why no factory option or standard?

18' boats used to "need" them more than they do now. Difference was that performance expectations were much lower, so people were happy with the status quo in performance (low) which was all they knew. Wooden boats from the 50's may look "retro" and cool to some, just like some people like '57 Chevies. But compared to modern technology, they're extremely low performance and high maintenance.

Modern hull designs outperform older ones in every way imaginable. Lighter, longer lasting, better low speed and high speed performance, better materials, more interior space, better ergonomics, more power, and relatively cheaper. What more do you want?

Higher maintenance for sure. But when you talk about "performance", that requires some defining. I suspect 9 out of 10 people would simply equate speed to performance. If fuel economy is what floats your boat, I would have to say it was engine technology that got us most of the way there, not entirely hull design.

Certainly (as I said in my first post), motors have gotten bigger over the years. So they go faster now. Along with that speed is the need to have trim tabs, which is what this topic started talking about in the first place.

"Need" must be defined as well. Trim tabs are "needed" because the owner perceives a problem with hole shot or bow rise. If that was a problem in the 1950's they would have been offered and the hydrofoil would have been invented back then as well.

Ergonomics and interior space are even further off topic. Regardless, that's very subjective. Look at some of the typical 18' upscale runabouts today and tell me where you can store a fishing pole. How about room to change a sparkplug. How about having to stand to see because the windshield offers poor visibility and is lower than your head anyway. But like I said, ergonomics to one man may be unacceptable to another.

BTW, my 1952 15' woodie is 18% lighter than my 2009 14' tinny, it goes 2mph faster with exactly the same HP and the "ride" (one of MY performance measures) in a heavy chop is far superior.

 

[haulnazz15]

Re: Trim tabs- why no factory option or standard?

Agree entirely, JimS123. My 76 MT is just about as fast top speed as any similar 21' runabout with a SBC. Fuel efficiency on mine is probably slightly worse on mine being carbureted.

I will say I have NO need for trim tabs unless I pile a lot of heavy people on one side of the boat. My boat planes out extremely fast as it is, so the addition of tabs or whale tails wouldn't net me much.

I do believe interior space suffered during the 80's/90's, but it has been making a comeback in the past decade. I see the difference in the footwell/seating space in my bow versus an 80's or 90's craft, and know that there's no way three or four people are going to be able to fit their feet in that tiny footwell.

Back on topic, the tabs really aren't considered necessary for most boats under 23', and since cost is already the main focus in the small boats, manufacturers aren't going to drop annother $50-100 in materials to satisfy a few people's desires.

 

[Mariah180]

Re: Trim tabs- why no factory option or standard?

Everything I've read be it a 1976 or 2006 said trim tabs are "amazing" "world of difference".

 

[642mx]

Re: Trim tabs- why no factory option or standard?

Everything I've read be it a 1976 or 2006 said trim tabs are "amazing" "world of difference".

You bet they are. I won't own another boat without them!

 

[dingbat]

Re: Trim tabs- why no factory option or standard?

Everything I've read be it a 1976 or 2006 said trim tabs are "amazing" "world of difference".

A well designed, properly powered hull benefits little from tabs in most situations. The only times I use mine is when it get really sloppy, I'm running across a heavy tidal flow, or I have the boat fully loaded with crew and fuel and need a little extra to get up and out of a hole.

Don't get me wrong. I wouldn't be caught w/o them but for cost consequence people they?re a luxury, not a necessity