"Wayne B" wrote in message
...

On Fri, 31 May 2013 11:23:33 -0400, iBoaterer
wrote:

We use about 8 gph towing a dinghy in flat water/no wind. That's
with
twin diesels running at 8 to 8.5 kts. In rough water we hoist the
dinghy up on deck.

Wayne, is that optimal and only goes downhill from there?!

====

If you increase speed over 8.5 kts it goes down hill very quickly. The
best I've ever been able to do is 1.4 nautical miles per gallon. That
was running down current in flat water on a single engine, at a little
over 7 kts. Running 7 kts on twin engines is problematic because
that puts you barely over idle speed which is not good for long term
durability.

-----------------------------------------

I guess that was a small advantage of Mrs.E's 36' GB with the single
120hp diesel. Cruise was about 7 knots burning about 1.5 gph. But,
there was no option to go much faster. I think 9 knots was about wide
open. Plus, I'd never trust a single engine for the kind of
cruising that you guys do.