Correct trim attitude

BruceK

BruceK

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I'm told she looks stern heavy. I'm not so sure. She's trimmed to best speed ( she's largely oblivious to revs and there's no fuel consumption readout).

What does the board think?

Note these boats usually have lighter petrol engines in, this has KAD42 diesels

13627201_10153624671607117_8451281099115909179_n.jpg
 
60 views and nobody wants to venture an opinion?

How about in this vid? Following sea, 0.8m swell allegedly. Here she does appear a bit bow high, not withstanding those times she's overtaking a swell, but again trimmed to best speed

 
looks about right, certainly on the flat water.
worth playing with tabs and drive angle to get best speed for set revs.
I find my T31/KAD43s gets best results with trim tabs fully retracted and legs set at 0 on flat water.
waves/swell will change whats needed.
 
In the video it does look a bit bow high to me,but looks ok in the photo.

if that's the trim angle that results in the highest speed for the chosen revs, and that's what you're trying to achieve (as opposed to maximising comfort in a head on sea for example) then its the correct angle regardless of what it looks like. You may choose to sacrifice some speed for a little more stability for example.
 
The photo looks about right to me for flat water.
Going upwind into a chop, you'd probably want to try and trim down a little further.
 
Thanks. To be honest the amount the bow comes down when coming off the plane is significant and still surprises me. She will lift nearly a third of her bow out the water at speed. I know traditionally the Formula has it's centre of gravity further aft than most express cruisers giving it more bow rise but my concern was although I have trimmed for max speed does the angle reflect a overly stern heavy boat . My legs are normally fully trimmed in with tabs about 30 -40 % down giving max speed. The Owners manual only recommends a few clicks of down trim in the tabs, but in that instance (say 10%) the bow rise is above the horizon and I'll drop 2 knts but the boat is very stable. Go to about 50 to 60% down on the tabs and the bow will drop a fraction but but not linear to the input, I'll lose 2 knts again and the boat becomes twitchy and liable to fall into a turn with the smallest steering input as seen in the video on the approach. At no point can I drive the bow down except at very low planing speeds, or speeds above 25knts when the tabs can fully retract. (getting past 25 knts here is a rare occurrence, the water is generally too choppy)
 
Elecglitch said:
:encouragement:
Click to expand...

You not one of Kwakers pirates are you? :p



This ties in with the Volvo Penta prop guide thread. Trying to work out why I should be losing so much speed of the stated performance for C4 props albeit achieving max revs. It's a conundrum that's baffling me
 
Hey, at least I managed yours in landscape. Can we try it again this time also with Dan's boat in?
BTW How is Greystones marina? Can you recommend? Good luck with the rest of the trip :encouragement:

 
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