In article . net,
otnmbrd wrote:

Jere Lull wrote:
In article .net,
otnmbrd wrote:


Some have a tendency to leave an engine in gear through an entire
portion of a maneuver .... or, in short, too long.


This is SO true. Pour on a fair amount of power, then hit neutral. That
seems to back us with little walk, then without the prop spinning, we
can turn wherever we want.

When coming port side to, if I want to pull the stern in, I back at just
above idle. If I want to stop without walk, I give it that "fair amount"
of power.

Take the boat out and try various power settings near something you
don't mind hitting. I think you'll be surprised.


"Pour on a fair amount of power", is going to depend on your set-up and
situation.
For some, using less power sooner may be the trick, as I generally find
that less power, less propwalk, but each condition can and will vary.

otn

Full agreement, which is why I stated it nebulously and suggested trying
it some place soft with that particular boat. In our case, we accelerate
to a knot or two in a half boat length, which is pretty hefty power in
reverse.

Each boat differs, but the basic idea of no prop walk if the prop's not
spinning is a constant.

--
Jere Lull
Xan-a-Deux ('73 Tanzer 28 #4 out of Tolchester, MD)
Xan's Pages: http://members.dca.net/jerelull/X-Main.html
Our BVI FAQs (290+ pics) http://homepage.mac.com/jerelull/BVI/

On Sat, 02 Jul 2005 00:53:26 GMT, "Roger Long"
wrote:

Having sailed on boats from 7 to over 300 feet, I tend to think of my
sailing experience as being fairly broad. I never thought about it
until today but, while it may be broad, there is a big hole in the
middle.

Most of my command time is in boats under 30 feet, small and light
enough to just manhandle around while docking and undocking. Pull up
to the dock, jump off, grab the rail, boat stops. My experience in
larger boats has all been as crew and most of those boats have been 60
feet and over so everything was done with well orchestrated line
handling and power.

We just moved to our permanent dock which is longer and narrower than
the temporary one we were on. The boat will not back out now without
the stern walking far enough that we’ll hit the boat on the other side
of the slip (mercifully, it hasn’t shown up yet but I’m trying to keep
the space inviolate for practice). My crew is small enough in stature
that our 32 footer might as well be one of the big sail training
vessels I’m familiar with as far as fending off or hauling the bow or
stern in with a dock line is concerned.

I lay awake the other night trying to think how we were going to get
out of the slip the next morning. I asked myself what they would do on
the schooner "Westward". Simple.

The next day, I explained the maneuver to the kids and guests. I then
set a stern spring planning to back against it to pull the stern in
and the bow out before casting off the spring. This would turn the
boat enough in the slip that she would have to straighten out in
backing and about double the distance I could back before the stern
swung too far.

I called for the bow line to be let go and put the engine in reverse.
Nothing happened. The engine ran and there was some thrashing under
the counter but the boat didn’t move. More power, nothing. It was dead
calm but the boat simply would not turn. I used about as much RPM as
the prop will absorb in bollard pull conditions and the boat still
didn’t turn. I finally said the hell with it, cast off the spring, and
we backed out taking a huge imaginary chunk out of the rail of our
mythical slip mate as we went.

The bottom line is that 15 horsepower in reverse through a two blade
prop on a heavy 32 foot boat isn’t going to do squat in fancy line
maneuvers. I’m going to have to make sure I always invite some big
guests for every sail or think of something else.

How do you do it?

Roger,

I curently have a 7-ton 36 footer, for which I traded-in a 31-footer -
both kept in inboard slips lining a narrow fairway across a lot of
current (river plus tides).

I always back-in to my narrow slip, whether against the ebb (3 or 4
kts) or with the flood (1 or 2 kts).

To do so, I first have to crab sideways into the fairway far enough to
line up for the slip entry next to my large powerboat neighbor (and in
full view and earshot of the "boating experts" lining the upper deck
rail of the restaurant at the shore end of the fairway g).

I have found that until I achieve minimal sternway (0.5kt to 1kt with
respect to the flowing water, not with respect to the ground), a
hard-over rudder with reverse power is not a rudder, but a speed
brake.

Once I have stererage way, my (until then amidships) spade rudder only
needs to be swung modest amounts to make the stern go where I wish
while facing astern at the helm.

If you're trying to move your bow out to allow for prop walk in
reverse, you'll have to remember that it's your stern that you steer,
and the bow follows.

That means that tying the stern hard to the dock isn't going to move
the stern the amount required to make the bow swing in the opposite
direction.

If you want to use prop walk constructively (a "stern thruster"),
large throttle deflections that are extremely brief don't give the
boat time to respond in forward or reverse, but do kick the stern - to
starboard with forward power, or to port with reverse power (assuming
your prop rotates clockwise when viewed from astern).

Conversely, to minimize prop walk, apply power _very_ slightly and
patiently wait for your boat to move. With a gentle hand and patience,
you'll find that you can gain reverse steerage way before prop-walking
into trouble. Only then should your rudder be anywhere but amidships.

If you want to power against a stern line to swing your bow out,
you'll need some slack in the line sufficient to let the stern move
the corresponding amount. In that case, your technique of powering
against a pre-turned rudder can work, but lots of power in confined
spaces makes me nervous.

I much prefer to maneuver at speeds no greater than those at which I'd
be willing to hit the dock.

Al
s/v Persephone
Newburyport, MA

Albert P. Belle Isle wrote:

To do so, I first have to crab sideways into the fairway far enough to
line up for the slip entry next to my large powerboat neighbor (and in
full view and earshot of the "boating experts" lining the upper deck
rail of the restaurant at the shore end of the fairway g).

Once or twice a season, you have to back it in at happy hour dead ship
with only the storm trys'l, then drive straight home without looking at
them or stopping in - just for effect. ;-)

On 10 Jul 2005 18:05:42 -0700, wrote:

Albert P. Belle Isle wrote:

To do so, I first have to crab sideways into the fairway far enough to
line up for the slip entry next to my large powerboat neighbor (and in
full view and earshot of the "boating experts" lining the upper deck
rail of the restaurant at the shore end of the fairway g).

Once or twice a season, you have to back it in at happy hour dead ship
with only the storm trys'l, then drive straight home without looking at
them or stopping in - just for effect. ;-)

I don't know which I'd find more problematic: trying to get into that
slip under _any_ kind of sail, or passing by without stopping in g.

Al
s/v Persephone
Newburyport, MA