Trying to get an 11 Meter on Plane

[David Jones]

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[David Jones]

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[David Jones]

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[mikeandanne]

This might not be the issue here but I remember a guy who had mistakenly painted the bottom of his boat with ablative anti foul designed for a sail boat or slow trawler to wear off as it moves---well he could barely get the boat up --- all was restored after he got that stuff off and the proper on ----again I say this is probably not the case here but interesting nonetheless -----Mike

[RWS]

When I had the gas engines, Tabman helped me change over from the factory tabs to a larger Bennett with DROP FINS.

After the refit to diesels, my top end is similar, however the larger props and additional lift have made the need to use the tabs insignificant.

This 11 Meter has diesels.

She SHOULD plane without the need for full tabs applied.

Just sayin.........

RWS

[ready123]

Those props look very small to me..... What size are they?
4 blades will help by lifting the stern and I would think you could add 2" to the dia of those.
Maybe RWS can comment on the size of his.

[prowlersfish]

Unless Its turning to much rpm I would not add 2" of prop . Not the same boat or engines as RWS

[Landlocked]

I hesitate to jump in here because due to a low top rpm I feel like I am not properly propped. (Our short jaunts on the lake don't justify, to me, the expense of changing props)

However, In my 11 Meter Sedan if we're going to run up over 1500 rpm I too have to deploy the trim tabs to run down the lake in a planing attitude. Without them being fully down we've got the nose up too high and the speed a couple of mph too low.

My boat has the Crusader 454's in it and I don't have the prop information here at work with me.

[ready123]

Unless Its turning to much rpm I would not add 2" of prop . Not the same boat or engines as RWS

RWS mentioned a test report of a boat with 24x28 props... They look smaller to me, what size are they David?

From comments here it seems something is wrong to require down tabs to achieve plane......
Either the engine power is way down or the boat is ass heavy or the props too small or ..... any more?

[yorklyn]

First of all I love that boat! Second these boats came from the factory with undersized tabs. yours are the same size as my 10 meter mid cabin. Not sure about the diesels as mine has twin 454s but when I first got it the only way to get her rear to come out of the water some and bow to come down without running with the tabs totally down was to run her just over 3500 rpm and watch the fuel gauge move quick. I fabricated three inch extensions to my 24 inch tabs to extend them to about 12 inches. it made a huge difference. I could then run on plane at around 3000 rpm with the tabs about 1/3 of the way down or 3250 and pull the tabs almost all the way up. I'm going to put bigger tabs on her before she goes back in.

[David Jones]

I looked back at my survey and it says that they are 24x28. I looked thru the pictures to see if he had a picture with the tape measure on it and the picture is very blurry but it looks to be be close to that best as I can see.

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IMG_6994.JPG (32.73 KiB) Viewed 8813 times

[David Jones]

Yorklyn,
How did you attach your fabrication?

[yorklyn]

I attached them with stainless bolts every few inches and made a 1/2 attempt to weld it myself. pretty sure bolts are all thats really holding them on. ran them like that for 4 seasons with no issues at all. i was originally concerned about the rams giving out but they held up fine

[yorklyn]

couldnt find a pic in my files. I'll try to take one so you can see.

[RWS]

First of all I love that boat! Second these boats came from the factory with undersized tabs. yours are the same size as my 10 meter mid cabin. Not sure about the diesels as mine has twin 454s but when I first got it the only way to get her rear to come out of the water some and bow to come down without running with the tabs totally down was to run her just over 3500 rpm and watch the fuel gauge move quick. I fabricated three inch extensions to my 24 inch tabs to extend them to about 12 inches. it made a huge difference. I could then run on plane at around 3000 rpm with the tabs about 1/3 of the way down or 3250 and pull the tabs almost all the way up. I'm going to put bigger tabs on her before she goes back in.

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In order to create the mid cabin from the original design, the deck was raised and the engines were slid aft to make room for the new "cabin".

This resulted in a shorter shaft and less distance from the shaft's center to the bottom of the hull, which required smaller props and a higher gear ratio.

The movement of all that weight aft and the decreased lift from the smaller diameter props created more ass end weight in the mid cabin vs the original 10 meter.

The engines in the 11 meter are below the helm, just as they are in the 10 meter.

Tabman looked at my performance figures at the 2002 Ft Lauderdale Boat Show and with the gas engines, it made sense to add the bigger tabs with drop fins.

while this addition helped improve the running angle, especially when running with a full tank of fuel and it allowed some increase in fuel economy I need to point out that at no time did the boat have any difficulty getting on plane, either with or without the tabs.

That is a fact.

Now, same 10 meter with the diesel engines, swinging bigger props, creating more lift - application of the tabs makes zero difference in speed.

Now, back to this 11 meter thread issue. This 11 meter has diesels, they weigh more, yes, but keep in mind this boat was available with gas engines and in fact the great majority of them left Lancaster equipped with gas engines.

So here's this 11 that struggles to get on plane with full tabs?

We have a boat review article with performance data that shows a significantly higher speed at WOT with the SAME boat and SAME engines.

So, while bigger tabs MAY well help performance, it is important to evaluate the entire issue in order not to mask what could be a different problem.

Perhaps Roger DeVore at 1st mate Marine or others will chime in here regarding the performance of the 11 meter, gas or diesel.

RWS