Euro boat design

[blueskyracer]

I was wondering what the purpose of the triangular piece between the rear shoes about 3 feet long does

[T Chance]

It helps get the boat on plane quicker in the European style beach start.

[Smitty]

How? Does it cause the prop to slip a little and let the motor rev or some-such?

[DeanFHobart]

How? Does it cause the prop to slip a little and let the motor rev or some-such?

Yes, it's as simple as that.

[Steve77t]

Uh, No, It helps to get on plane through a lifting moment. The prop is buried at this point to help with this, Then the boat rides high enough and the lift is changed for top speed, Steve

[Steve77t]

Uh, No, It helps to get on plane through a lifting moment. The prop is buried at this point to help with this, Then the boat rides high enough and the lift is changed for top speed, Steve

[John Schubert]

Uh, No, It helps to get on plane through a lifting moment. The prop is buried at this point to help with this, Then the boat rides high enough and the lift is changed for top speed, Steve

Also remember they have hydraulic up & down lift that also gets the motor up during planing & also increases the rpm's quicker

[Smitty]

We're talking about that skinny triangle of wood right in the middle, correct? How can that possibly have enough lift, especially at the very low speeds of climbing on plane, to have the effect you describe, Steve? If you wanted more lift, you'd widen the planing surfaces. That little triangle could add a little lift at 90 mph, not at 5 mph.

But it might divert some water to either side of the upper part of the gearcase, maybe. When Entrop and a few others in Reg. 10 were experimenting with prop-riders, they noted that the gearcase, which was set-up well below the bottom of the boat (something like when the Europeans have their engines power-trimmed down low for plane-off), had to shove a lot of water out of the way until they got going fast enough for the back of the boat to come up to prop-riding attitude. Jim Hallum talked about trying something similar to that triangle, but by that point Gerry Walin had got hurt and was done racing.

But I've been wrong once or twice before . . . .

[epugh66]

Steve's right..... even if he is a runabout guy ;-) Relative to the "transom/boat bottom" the propshaft is about two inches deep. Once on plane and at speed, the propshaft is more relative to the ''running surface of the boat'', those two rear sponson/wedges.

If you're puzzeled by these boats, you should have seen what the Russians were doing with catamarans and trimarans during the 80's.