On Nov 11, 12:15*pm, Dylan Smith wrote:
On 2009-11-10, a wrote:

radius. *There's the aviation reference, multi engine issues! Now

Indeed there is. My multiengine instructor also owned a boat, a 35 foot
planing hull type boat with two large V8 engines, and of course separate
propellors. We went out on the 4th July, into Galveston Bay, one year.

The boat would happily do 30 knots all day long at what passed for
"economy cruise", if I remember right, on both engines. It steered
beautifully on two engines. The props, like some multiengined aircraft,
were counterrotating too. But that night one of the starter motors failed
on the engine that turns the "non standard direction" (i.e. the one
with the really expensive starter motor!) letting out the magic smoke.

We had to come back in on one engine. On one engine, it steered like a
cow, and lost about 90% of its performance - it would not do more than
about 5 knots full bore. Very reminiscent of the problems with multi
engine flying. Except, of course, for the lack of the falling-out-the-sky
bit if you got too slow.

Even more aviation: you could not maintain altitude: couldn't get up
on to planning speed.

But 5 knots? My 25 foot swing keel O'Day (think of the keel as a
vertical wing) could do that in a reasonable breeze and it
was NOT a fast boat.

It hurts my head to think about what parts of the two engines were
common, and which were different.