Factory trim tabs revisited

[Megabyte]

I had an opportunity to get some close-up photos of factory mounted trim tabs on two new Parkers this weekend at the Bay Bridge Boat Show.
The tabs in both cases are Lenco electrics, but it is interesting to see the difference in design and mounting position between the tabs mounted on a Parker 2310 and a 2520XL.

Here are the tabs mounted on the 2310.
While you are at it, compare the scuppers on both boats...

Here are the tabs on the 2520XL.

And as many times as we've collectively taken the factory to task about their selection of (what we believe to be) too-small trim tabs, take a look at the tabs on this Boston Whaler at the show.
I'm wondering why they even bothered? :roll:

 

[cbigma]

take a look at the tabs on this Boston Whaler at the show.
I'm wondering why they even bothered?

Let's see,,, if I am a BW salesman I would say....umm.... "well, you know, the BW hull design is soooooo finely tuned, that they only need a very tiny tab. It's much more efficient" :roll: :roll:

If you assume that their bootstripe is at or close to the waterline....extend that line around to the transom and the pocket that holds their (ahem!) tabs. The top of their actuators look like they penetrate the hull at or below the waterline! YIKES! :shock: :shock:

 

[Outta Here]

Let's see,,, if I am a BW salesman I would say....umm.... "well, you know, the BW hull design is soooooo finely tuned, that they only need a very tiny tab. It's much more efficient" :roll: :roll:
quote]



:roll: "Oh yeah, no need to reduce the pounding on a BW" :roll: :roll: "Already ride too smooth" :roll: :roll: :lol:

Those oval scupper covers cover 2 single round scuppers (not 1 oval scupper).

I'm convinced no boat builder is gonna put larger tabs on their boats. Too easy to screw up and get hurt or even sink boat by pitchpoleing in a following sea w/tabs down.

Personally, I would like 1 tab that ran the entire beam of the boat.

 

[cbigma]

I'm convinced no boat builder is gonna put larger tabs on their boats. Too easy to screw up and get hurt or even sink boat by pitchpoleing in a following sea w/tabs down.

I did an informal survey at the New England Boat Show and I think you may be on to something. Nothing larger than a 12X18 on 45' or less. And it's not like a few more square inches of Stainless plate would break the bank,, so there could be something to the liability angle. Boat builders have no control over the piloting skills of the folks who buy their boats, so they keep things on the conservative side. Which is fine with me, it keeps them in business longer. 8) 8)

 

[esfishdoc]

The tabs on GW would be good for leveling and that is about it.

There are issues with large tabs that could easily confuse a novice and possibly get him or her in trouble.

As you may know I took it to the max by installing 30 X 9 Bennett's on my 2520 XL. With the tabs fully deployed I can just about clean my anchor... well, not quite but it is extreme. They almost act as air/water brakes when fully deployed but they are usefull in making a tolerable ride when the bay gets very choppy in those real tight rollers.

In playing around with them fully deployed it keeps the bow down so well that with all the resistance from the hull and tabs that a maximum speed of around 22 is all that is possible before the prop starts to blow out once in awhile. On the other hand I can do 21 mph in conditions where with the stock tabs it would have truely pounded tring to get going that fast.

I did have one experience with a sharp turn from a head sea to a following sea and didn't get my tabs up. Wow! This is where someone could get in trouble.

So maybe there are some liability issues with tabs at the extremes.

Here is a link to a video shot just yesterday. One thing I've noticed about video and pictures on the water that it flattens out the water. Karen and I were out drum fishing on the seaside. As we were out there a Northeast wind picked up making the ride back in much rougher than going out. I was running against the tide and a quartering sea from my starboard. The waves were easily two foot that were fast and tight. I didn't get any of the real good splashes. I was running about 21 mph and getting about 1.8 mpg..... and my tabs were not fully deployed!

There is no way I could have run more than about 16 with the other tabs.

http://s141.photobucket.com/albums/r74/ ... I_0043.flv

http://s141.photobucket.com/albums/r74/ ... I_0042.flv

Richard

 

[cbigma]

Richard...

Excellent Videos! By running a pan shot from the helm to the cooler in the stern, you clearly illustrated that while there was a bit of a pounding in the cabin, you could have enjoyed a cuppa chowdah in the stern without spilling a drop! 8)

We'd all like to know how the Admiral could read a novel while all this was going on. Does she have some kind of NASA vision stabilizing system? I'd be lucky to be able to hold the book in my lap, never mind read it! :shock: :shock:

I also upgraded tabs this spring, albeit in a less dramatic way than you did. I went from OEM 12X12 to 12X18. I feel better that all the components are now new (2000 model year hull). As far as ride quality goes, what I succeeded in doing was merely reduce the amount of deployment that I need to gain the desired effect. I guess I should have seen -that one- coming.

I -do- have to be more careful in deploying tabs at speed now, because just a minor adjustment with any speed has a more pronounced effect on trim and handling. Again, this is what would be expected. I have a 14-degree MV hull, and I imagine that is a contributing factor to the sensitivity in trim with larger tabs.

John

 

[esfishdoc]

Karen can manage to read in any condition. I've never seen her put down a book. I would get sick!

 

[sea1skiff]

what do you mean by pitchpoleing?

 

[esfishdoc]

As the boat starts riding down a wave in a following sea the bow gets stuffed and causes a sudden braking in the forward motion. The bow plows deeper into the water while the force of the wave now lifts the stern up. By the time the boat is verticle and everyone has their face planted in the windscreens the "oh sh ts" are already done as the boat is now going upside down. The wave goes over the bottom of the boat while water is rushing in. Any one who is concious will now be fighting for their lives trying to get out of the boat and to the surface. Don't forget the EPIRB!

Richard

 

[Bryan 2530]

Awsome video. You guys are killing me. I need to get my new Parker in the water. Thanks for killing my motivation at work today.