bertram31.com

The published COG on a Hard top B25 with 165's is 16'5" aft of the bow. My thought to properly distribute the weight of 190 gallons of fuel is to straddle this COG, with one tank aft and one tank forward of it. However, this leaves me with a huge amount of dead space forward. I can use it, but I'm wondering what the negatives of moving both tanks forward of the COG would be. Doing this would give me more room in the engine bay to place batteries with in turn would mean shorter runs to the engines. Any informed opinions???

CMP

darn,,,,, it has to be an informed response.... Ask Thuuuud. He'll know.

I posted a method for you to calculate the location of the CG for various configurations over on the '25 board. But here I will offer a far more simple and direct method to answer your question.

Run your boat until the tank is near empty. Then get a three or four guys who's total weight is about equal to the total weight of the fuel you want to bunker. Head out with them standing about over the present tanks. The boat should handle as it does now with full fuel.

Then have them move forward to where you think you might like to put the new tanks. See if you like the handling.

More than likely you don't have to actually conduct this experiment. Just ask yourself if you think the boat's handling is going to change dramatically when a three or four passengers move themselves a few feet forward.

A 100 gallon gasoline tank two feet forward of the CG has a moment of 1200 ft-lbs. (gas weighs about 6 lbs per gallon.) A 100 pound teenager standing on the foredeck 12 feet forward of the present CG has the same moment of 1200 ft lbs.

I'll bet your boat would handle just fine with a teenager on the foredeck!

Peter

LOL-thanks Peter, I read your post and my hair still hurts! I also spoke with some naval architect folks I know locally and they concur with your numbers. Add that to the fact that the boat tends to run bow high anyway and I'm moving 2/3's of the fuel fwd of the COG by 18 inches...

CMP

I haven't been able to get on the message page of the B25 board for quite a while, I thought it was gone. Can someone help me with this problem?

Thanks

Trey Dibrell

Judge,
The page was inaccessible for a day or so, but it's back. Here's the link I use to get on:

http://www.simplifying.net/cgi-bin/plug ... tion=intro

Give that one a try.

-Kel

CMP...Peter...Kelly...Trey...Buju

The gangs all here, where are ya James?

Sorry Walter...didn't mean to leave ya out!