On Wed, 23 May 2007 11:48:04 -0500, Vic Smith
wrote:

Would a trawler with twins normally power using both engines?
Taking the question of twins out of the realm of speed and into
a fuel miserly usage puts a different light on twins.
What's your experience with twins in a trawler?

I have a trawler with twin diesels, and running on both engines is the
normal mode of operation for us and others. I like the redundancy but
I'm sure there is a price in fuel economy. It's difficult to say just
how much but probably at least 50% greater. At low engine output
there is a great deal of power wasted just in overcoming friction in
the redundant engine, transmission and running gear.

Either of my engines could easily power the boat at hull speed in
normal conditions. Running single is a possibility but that has other
issues, and you are also dragging around a large unused prop.