Prop Walk Catalina 36 MkII

[John McConnell]

A year ago I purchased the '02 model. Lots of small issues (previous neglect), recently changed pen and now must revers out to starboard. Huge prop walk to port making it impossible to turn bow to port.
What is the best method to deal with this problem.

What a fantastic craft, thoroughly enjoy her. Sail no.2088. We are in Perth,West Australia.

Any ideas please.

John McConnell.

 

[weinie]

I find the trick is to give a good burst of power to get moving backwards and then throttle down or neutral. The stern will indeed swing out. But once you have enough speed and water rushing by your rudder, you can regain steerage with the throttle at minimum or transmission in neutral.

 

[shipwreck66]

I guess size isn't an issue here, I have the same setup, same issue with my C27. A friend of mine has a 2005 C36, I'll see if he has any suggestions.

 

[Stu Jackson]

I find the trick is to give a good burst of power to get moving backwards and then throttle down or neutral. The stern will indeed swing out. But once you have enough speed and water rushing by your rudder, you can regain steerage with the throttle at minimum or transmission in neutral.

Yes.

You could also use a spring line to help you turn.

You could also do a search here on the phrase prop walk and have years of reading!

You may also want to consider joining the C36 forum at www.c36ia.org.

Congrats on the new boat.

 

[John McConnell]

Thanks wienie,just the advice I was looking for. Good to know I have joined such a supportive family. John.

 

[John McConnell]

Thanks for the help,great to know I have joined such a supportive family. John.

 

[Stu Jackson]

After all these years...

...something just occurred to me.

When we drive, we rarely GOOSE it in reverse.

Maybe that's why so many people have difficulty with prop walk, because they don't take the recommendations to goose it in reverse seriously. Unless water is flowing over your rudder, it won't be able to do anything to help your direction.

Just may be the reason prop walk is one of the most recurring issues for new boaters.

 

[jimmcgee]

What I had to learn was not to keep it in reverse. I'll get her moving and slip into neutral, a little more reverse then back into neutral. No prop walk when you're not in gear...

 

[Don Guillette]

PROP WALK is your friend and is something every skipper has to deal with and here's how to make prop walk work for you.

First, let's assume you have clockwise right hand rotation. If you have counter clockwise left rotation just reverse what I'm telling you. Secondly, increasing acceleration will just make things worse so go easy on the accelerator. Thirdly, what I'm about to tell you is hard to visualize sitting at a computer and also when you decide to practice do it in the turning basin until you get the hang of it.

PORT SIDE DOCKING: approach the dock at slow speed with the bow angled toward the dock. Center the rudder and put the engine in reverse. The stern will swing nicely toward the dock. Here's where skippers get into trouble in this situation. Instead of centering the rudder they turn it to port with the engine in reverse. Nothing happens at first so they goose the engine. As soon as they do that the stern turns to starboard. To correct that situation they then turn the rudder to starboard and that is when things really get screwed up. What they should have done after centering the rudder is NOTHING.

BACKING THE BOAT: At my dock I need to back out and have the stern turn toward starboard so I can exit the slipway to the turning basin. Here's how I do it. The first part of what I do is obvious but the second isn't. I obviously start with the rudder centered and the engine in reverse. Once about 3/4 of the boat is in the slipway I use PROP WALK to my advantage and I put the engine in forward. Sounds wierd but the stern swings slowly to starboard.

Say at this point I suddenly notice someone is coming down the slipway and I don't have time to fool around and have to get out of the way quickly. To whip the stern around I'd still stay in forward but I'd turn the rudder to port and goose it. The stern will rapidly turn to starboard.

Spend a few minutes in your turning basin to get the idea of how the forward or backward motion of the boat is influenced by the position of the rudder with the engine in forward or reverse. Also, you want to see what happens when you goose the engine in each situation. What you'll notice is that if your rudder is not in the correct attitude things go badly very rapidly.

Once you get good at using prop walk to your advantage you can actually spin the boat around on its own axis. My slip way is narrow and one time I came in too hot and missed my slip. The next stop would have been the rocks at the end of the slip way but because I can actually spin the boat on its axis there was no problem.

 

[shipwreck66]

Thanks Don, that explains the oddity I noticed when I accidentally put her in forward instead of neutral a couple of times during backing. It is encouraging to know that I'm not the only one who has this issue.

 

[Don Guillette]

Here's another situation that I've seen a happen a million times at Avalon (Catalina Island) but it happens also in every harbor in the world. The skipper is approaching the mooring a little faster than he should. The rudder is centered, which is good, but then he floors it to stop the boats forward progress. I say to myself as I watch what is happening DON"T TOUCH THE RUDDER but they always do and that is when things go from bad to worse. The boat goes in an unepected direction and then the skipper over corrects and it ends up being a Chinese fire drill. Actually, the Chinese fire drill is better organized!!

It really doesn't take a lot of practice to get to know your boat so you can use what it does to your advantage. When funny things start to happen under power or sail you know instantly how to get out of the situation or more importantly, to never get into the situation in the first place.

 

[Buzzlovelace]

I had a lot of the same problems, I took the NauticEd course on line "Manuvering under Power" It was great. I now understand it better and have no problems. If youy decide to go this way please refer me so I can receive some credit. TY

 

[OldCat]

Say at this point I suddenly notice someone is coming down the slipway and I don't have time to fool around and have to get out of the way quickly. To whip the stern around I'd still stay in forward but I'd turn the rudder to port and goose it. The stern will rapidly turn to starboard.

All very cool, just to add that this is also known as Prop Wash. The flow off the prop in fwd gear to the rudder "bounces off" the rudder and turns the boat, the rudder works even if the boat is not moving. More throttle, more wash.

Five forces: prop walk, prop wash*, wind, current, & if moving adequately: the rudder in the normal manner.

OC

*prop wash is dependent on prop to rudder geometry, but every Catalina that I know of with an inboard has geometry that makes it work well. Owners of bigger Cats comment as needed, but I have driven C27, C30, C34, C36 & prop wash worked as Don described...

 

[John McConnell]

All very cool, just to add that this is also known as Prop Wash. The flow off the prop in fwd gear to the rudder "bounces off" the rudder and turns the boat, the rudder works even if the boat is not moving. More throttle, more wash.

Five forces: prop walk, prop wash*, wind, current, & if moving adequately: the rudder in the normal manner.

OC

*prop wash is dependent on prop to rudder geometry, but every Catalina that I know of with an inboard has geometry that makes it work well. Owners of bigger Cats comment as needed, but I have driven C27, C30, C34, C36 & prop wash worked as Don described...

When entering pen, wind on starboard stern quarter, upon engaging reverse to slow forward momentum, stern immediately swings out to port.