I have followed the discussion of the use of PTOs from a generator and
designing twin engine boats.  This raises for me the question of what is
wrong with an auxiliary or wing engine as seen on many trawlers.  These are
typically 27, 40, or larger horsepower Yanmars with their own shaft and
variable pitch props.

The costs are similar to the generator take off and less than a twin engine
boat. Easier to maintain - although you must remember to exercise the wing
engine monthly, and is independent of the main engine.

Marty Campanella

Bay Pelican KK42

In reading Ken William's blog, I got the impression that he analyzed the
issue of wing engine versus twin and felt that the difference did not
outweigh the advantages of redundancy. Of course, he is making long ocean
voyages while those who are going coastal or the Caribbean or Alaska may not
require full redundancy. BTW, Nordhavn uses folding props, not controllable
pitch props. Folding props are less likely to foul and they place the prop
forward of the main.

Ron Rogers

-----Original Message-----
From: Marty Campanella

The costs are similar to the generator take off and less than a twin engine
Boat.

Ron Rogers said, " In reading Ken Williams' blog, I got the impression that
he analyzed the issue of wing engine versus twin..."

I don't know that I've analyzed the two options, but I certainly have
strongly held opinions...

Here's why I went with twins:

• A huge issue for me was the improved tight quarters handling of twins
  versus a single engine boat. I have seen a lot of marinas with current
  INSIDE the marina, and high-wind mooring situations. I want all the help I
  can get in these situations.

• I had a problems with my feathering prop on the N62. It had a nasty habit
  of getting stuck open. This caused a strange vibration. Once identified,
  getting the prop to close wasn't hard, but getting it to feather properly
  was a constant annoyance.

• The feathering prop, located off center, is very inefficient. Let's say I
  am in the middle of the Pacific and lose my main engine. If I shift to the
  feathering prop, range goes down, as does speed. With twins, if I run single
  engine, range goes up, and speed stays the same. See the difference? Each of
  my twin main engines is fully capable of running the boat at full speed.

• The wing engine is a different engine than the main engine. This means
  storing two different sets of spares (belts, hoses, filters, pumps, etc).
  Whereas I store a single set. [Note: I goofed on this one, and should have
  gotten twin generators, but I have a 20kw and a 25kw...oops]

On the negative side, there is a permanent loss in range, and permanent
increased fuel cost, as a result of having twin engines. I have not been
able to quantify this, but would guess that it is in the 5 to 15% range. For
me, the benefits outweigh this cost.

Overall, I am convinced that twins are the right answer, but ONLY if you
have the space to put them, and can afford the loss in range and higher fuel
consumption. Twin engines should not be shoe-horned into boats that cannot
accept them. There are many sportfishers out there, that are a nightmare to
maintain, because of inadequate space. I have a huge engine room, so this
was a non-issue for me. I don't know that Nordhavn would agree, but in my
opinion, the N68 is the smallest Nordhavn that has the engine room space to
comfortably handle twin engines.

-Ken W

Hatteras has just launched a sportfisherman with 22 foot beam. It is their
first triple screw boat! I don't know about maintenance room, but the owner
isn't going to be down there save for inspections. It is not a boat with
passagemaker range. In fact, it is likely that they will have to fill-up
every time they complete a round-trip to the East Coast canyons just beyond
the Continental Shelf.

Ron Rogers