Originally Posted by 9D280
As I said, if the speed limit is 10 knots...... I have a lot of open and speed limit free (well, most of it!
) water to play with. Time to plane & slow planing speed is irrelevant to me compared to the fuel consumption increase brought on by the drag. In Nick's case the fuel consumption will probably drop, as the hull drag not planing will be far geater than dragging the fins through the water at relatively low speed.
Dunno about all of that! Where did 10 knot speed limit begin to be a factor? Fins assist a 4.7 meter SeaRider hull in getting most of the way up on the step at 7-8 knots, and stay there. That speed is desirable for dragging baits. If I choose to haul ass, the difference between 29 and 31 knots does not ruin my Christmas.
I left my engineering calculator in the pub but....With the wetted surface of an average Rib combined with the leg of that noisy thing sticking down into the water, you're telling me that hydrodynamic fins of less total surface area than than a dinner plate are going to have a significant effect on my fuel economy? Were I so sensitive to be concerned about a rise of .002% in consumption, I'd get a row boat and be done.
I still don't get your "bow plunging precipitously" comment which has been posted before. I suppose with really evil trim, all my gold jewelry and a fat girl stashed in the bow I could induce a plunge as well but to blame it on the fins, I just don't agree. This is behavior that neither I nor anyone I have ever spoken with that used them on hard boats or ribs, has ever experienced.
I am not "anti" lifter. Fins however are not evil, don't cause the bow to plunge, don't negatively effect handling, don't ruin fuel economy which sucks to begin with, and are nice to use as a step to get one's ass back in the boat. If anyone wishes to select an alternative method to enhance trim on their boat, that is a fine decision in my book. Don't discourage use of fins though for reasons that just don't hold up to the vast experience of people that do use them. "I don't like fins because they refuse to speak Portuguese" uh well then I'll try something else