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Joe
 
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Default 3 or 4 blade props?

Again, you are saying that you use trim tabs (creating drag) to push
the bow into the water, leveling the boat.


No, you raise the stern, and lower the bow, but not to the point your
plowing it into the water.

My contention is that the more wet surface of the hull, the more drag you

are creating.

There's your hang-up, correctly deployed tabs *do* reduce the wetted surface
when correctly deployed at slow to medium speeds.

Now, you may like the nice level ride, but it is still creating drag.
Twice. One, the tabs are creating drag, two the bow is creating drag. Now,
does the efficiency improve?


No, at the slower to midrange speeds the drag the trim tabs reduce exceed
the drag produced by trim tabs themselves.
First the stern rises, then the bow lowers (not to the point of plowing)
reducing the wetted surface. Add to this the more efficient prop angle and
you will see an increase in overall efficiency. Again, they must be used
correctly.

I'll agree, with a caveat. SOME boats may
actually see a gain in performance, with the prop angle closer to
horizontal, and the stern being up out of the ditch,


So now you do agree that there can be an overall efficiency gain from the
drag produced by trim tabs.
Why didn't you start out your post with this statement?

but a good planing hull may actually be less efficient. It's a boat to boat

kind
of thing. Some may improve, some may not.


Your getting closer, but all planing hulls will benefit from the addition of
trim tabs to some degree.
Every planing hull will achieve plane faster and be able to cruise more
efficiently at slower speeds with trim tabs.