Capt. Mooron wrote:



| Quite possibly correct, but when going astern, there would be no prop
| wash past the rudder and I would say most would see the affects of
| propwalk to a greater degree when backing. G You don't have to
| completely agree with me any more than I do with you. We're talking the
| possibilities, here.

Gothcha... I'm just not correctly differentiating between flow and wash on
the prop in my original reply. My prop actually becomes narrower further
down. The prop is angled so that the flow would be strongest at the point
where it begins to narrow the most. I believe that's the reason I have such
a bitch of a time with propwalk to starboard in reverse.

CM

So, you've also got a lefthand prop (There are more of them out there
than people realize).
I really can't say, whether the above is the reason, or not. In "most"
cases, single screw, no matter what the hull design (inboard, fixed
pitch prop, right or left) when backing down, you are going to get a
serious condition of prop walk, which can be a pain and a boon to boat
handling (exceptions noted). However, there are many boats/ships out
there, that 8 out of ten times will torque as expected .... the next two
times they'll go in the opposite direction, for no reason, or at least
none that you can figure out at the time.

otn

"otnmbrd" wrote in message
| So, you've also got a lefthand prop (There are more of them out there
| than people realize).

Yup...

| I really can't say, whether the above is the reason, or not. In "most"
| cases, single screw, no matter what the hull design (inboard, fixed
| pitch prop, right or left) when backing down, you are going to get a
| serious condition of prop walk, which can be a pain and a boon to boat
| handling (exceptions noted). However, there are many boats/ships out
| there, that 8 out of ten times will torque as expected .... the next two
| times they'll go in the opposite direction, for no reason, or at least
| none that you can figure out at the time.

I try and use it to my advantage whenever possible. I have found that with
short bursts of high RPM I can compensate for most of the walk... some of
the time. For a full keeler I can spin it on a dime in quite water by short
bursts of forward and reverse.

CM

Every boat, operator, and set of conditions differ. I try never to use
any more power than is necessary, but, what works for me, may not work
for the next guy. A nice full keel sailboat, is one of the best learning
experiences for single screw powerboating, as they tend to be very
predictable, and relatively responsive to gentle prods.


otn

Capt. Mooron wrote:
"otnmbrd" wrote in message
| So, you've also got a lefthand prop (There are more of them out there
| than people realize).

Yup...

| I really can't say, whether the above is the reason, or not. In "most"
| cases, single screw, no matter what the hull design (inboard, fixed
| pitch prop, right or left) when backing down, you are going to get a
| serious condition of prop walk, which can be a pain and a boon to boat
| handling (exceptions noted). However, there are many boats/ships out
| there, that 8 out of ten times will torque as expected .... the next two
| times they'll go in the opposite direction, for no reason, or at least
| none that you can figure out at the time.

I try and use it to my advantage whenever possible. I have found that with
short bursts of high RPM I can compensate for most of the walk... some of
the time. For a full keeler I can spin it on a dime in quite water by short
bursts of forward and reverse.

CM