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Re: Forced air ventilated stepped hull?

Quote:

Originally Posted by Panther

I've got an idea for a ventalated hull that doesn't require steps but does the same job because it's not the steps that do the work, it's the air bubles under the hull that reduce the friction.

I'm not an engineer so who knows if it would work but a flat bottom boat could be easily re-configured to do a side by side test.

Design would be a derivative of a standard bottom boat but would have air holes underneath, the bottom would look something like this;

Bob Bull did this with a 26 Velocity a back in '98, don't think it worked.

Re: Forced air ventilated stepped hull?

Quote:

Originally Posted by Mark Mathews

Extreme and Phantom both have ventilated hull designs in their race boats. In 2004, a NON ventilated Extreme beat a very proven Ventilated Extreme at the KW Worlds. I toyed with the idea of buying an Extreme this time last year. The builder of the boats told me not to bother with paying the extra $$$ to build a ventilated hull. It was because he felt the ventilation gave a negligible improvement.

First the Extreme has a "self-ventilating" step. It is designed to pull the air from the sides and dump it under the step. With the air ventilated step we did not see any major difference between Gary and Shanes boat -v- High Noon or Wild Ride. Mark and I both agree that the "air ventilated steps" may have a disadvantage at the start of a race due to the weight of the water packed in the ducts while not on plane.

All the SVL Extreme's are running simular speeds with or without the "ventilated step".

The first 29 Shotgun has a "vetilated step" but we have not cut the ducts in yet. We wanted to run the boat without it first to check the speeds and then cut them in later to see if there are any gains.

Dave

Re: Forced air ventilated stepped hull?

Quote:

Originally Posted by mr_velocity

Bob Bull did this with a 26 Velocity a back in '98, don't think it worked.

Oh well... I had some free time yesterday, the creative mind was trying to work.. :D

I wonder what it looked like?