Thanks Brian. I was expecting a much lower fuel consumpiton figure than
either what you or Steve calculated. More in the range of what Wayne gave me
here

"If you cut your speed back to no more than about 1.1 x SQRT(LWL), about 7
kts, you can probably get your consumption well below 1 gph. I have a 30
ton 49 footer with twin 671s. At 1000 RPM we get 7 kts at about .7 gph, at
1300 RPM 8.5 kts at 1 gph."

I've heard commercial fisherman up here (B.C. Canada) brag about the
economy of their 6-53s in 35' - 40' trollers. Heavy built, beamy,
displacement hull workboats. 2 - 3 gph is what I recall guys telling me but
I sometimes can't believe what I remember. It's been 25 years since I was
involved in that fishery.

It's all a moot point since the boat in question has now sold. Still, It
would have been a neat, relatively cheap adventure for this old seadog.
Might have had some good times and sold the boat at profit a few years on.
You wouldn't believe what a "dock condo" rents for in Victoria harbour right
now.

Don





I didn't mean to pastronize - I like to help!
But accuracy is not at stake. It's all the variables.

How about this approach - for any diesel,
say 0.4 lb of fuel per HP hour
So an honest 100 HP costs 40 lb/hr = 7 gal/hr
an honest 200 HP costs 14 gal/hr

A 100HP drives different hulls at different speeds. Naturally.


Brian Whatcott Altus OK