My Catalina 30 has an absolutely wicked prop walk in reverse leaving or entering the slip. I've tried short hard engine bursts and slow and steady low revs but the result is the same. Would a three bladed prop make any difference ?. Jim G.
- Status
Likely make it worse
We have a 1988 Catalina 30 with a 12X12 three-bladed prop. It has a LOT of prop walk. We're used to it and often use it to help spin the boat when we need to. One thing that works for us when backing out of our slip is to give a little throttle (not a sharp burst), get the boat moving, then coast back in neutral. With the transmission in neutral there is no prop walk at all and you can steer normally. Your mileage may vary, but it's the best we've managed to come up with so far. Gary Kunkel
We have a 1988 Catalina 30 with a 12X12 three-bladed prop. It has a LOT of prop walk. We're used to it and often use it to help spin the boat when we need to. One thing that works for us when backing out of our slip is to give a little throttle (not a sharp burst), get the boat moving, then coast back in neutral. With the transmission in neutral there is no prop walk at all and you can steer normally. Your mileage may vary, but it's the best we've managed to come up with so far. Gary Kunkel
That's the nature ...
Cat 30's walk to port in reverse, it's part of their nature. When I first got mine, I would have sworn that it was not possible to back to starboard. All you have to do is practise. You can get steerage astern before the boat goes sideways if you use the shift and throttle correctly. Once you have steerage you can reverse quite nicely. I have to reverse about 4 boat lengths to put my boat on the end of my dock, starboard side to, facing upwind. It is now an easy routine.
Cat 30's walk to port in reverse, it's part of their nature. When I first got mine, I would have sworn that it was not possible to back to starboard. All you have to do is practise. You can get steerage astern before the boat goes sideways if you use the shift and throttle correctly. Once you have steerage you can reverse quite nicely. I have to reverse about 4 boat lengths to put my boat on the end of my dock, starboard side to, facing upwind. It is now an easy routine.
depend on current/future prop pitch/diameter/brand
My 88 Catalina wing keel, Universal M25xp 23hp diesel, with 3-blade Michigan 10x13 prop has only 'very mild' port stern walk when backing-up. All I need do is start off with the the wheel full to starboard and then slowly return it to amidships and she backs up straight as an arrow. However, before I had the prop checked/trued a few years ago it did have much more port stern walk (I was able to see blade differences just rotating it, but it was never hit/damaged). I always thought the stern walk was due to the initial 'slapping' of the blades having greater side directional force than the rear thrust until the boat has enough water flowing over the rudder to compensate and direct the boat sternward. The port stern walk can be amplified if the blades are not true. So if I am correct, then a trued prop or a prop with more rearward thrust (than what you currently have) should reduce port stern walk. More thrust could be acquired via more blades or more pitch or a combination thereof. Per a 1994 MIT prop study published in Pratical Sailor's January 1, 1995 issue, the following 3 props (most thrust listed first), all had more reverse thrust than a Michigan 2 blade fixed: 1. Michigan 3 blade fixed 2. Campbell 3 blade fixed 3. Campbell 2 blade fixed So, improvement will really depends on what you have now. Also consider reviewing the IC30 website, there may be additional information there which will help (link below). Hope this helps...
My 88 Catalina wing keel, Universal M25xp 23hp diesel, with 3-blade Michigan 10x13 prop has only 'very mild' port stern walk when backing-up. All I need do is start off with the the wheel full to starboard and then slowly return it to amidships and she backs up straight as an arrow. However, before I had the prop checked/trued a few years ago it did have much more port stern walk (I was able to see blade differences just rotating it, but it was never hit/damaged). I always thought the stern walk was due to the initial 'slapping' of the blades having greater side directional force than the rear thrust until the boat has enough water flowing over the rudder to compensate and direct the boat sternward. The port stern walk can be amplified if the blades are not true. So if I am correct, then a trued prop or a prop with more rearward thrust (than what you currently have) should reduce port stern walk. More thrust could be acquired via more blades or more pitch or a combination thereof. Per a 1994 MIT prop study published in Pratical Sailor's January 1, 1995 issue, the following 3 props (most thrust listed first), all had more reverse thrust than a Michigan 2 blade fixed: 1. Michigan 3 blade fixed 2. Campbell 3 blade fixed 3. Campbell 2 blade fixed So, improvement will really depends on what you have now. Also consider reviewing the IC30 website, there may be additional information there which will help (link below). Hope this helps...
Learn to spring off
Obviously this prop walk is a problem to you because you're singlehanding your vessel. If you had crew you could easily bump the bow this way or that while backing. As the others say prop walk can be to your benefit in many manuvers. I wouldn't trade the benefits for a boat that could back astern better. Learn to use spring lines to your benefit its simply a matter of time before you're going to need to know how. Like the next time your at the fuel dock 10 feet behind a big ol cruiser and some schmuck in another big ol tub pulls in behind you and the wind is pushing you and holding your boat to the dock. Check out the link.
Obviously this prop walk is a problem to you because you're singlehanding your vessel. If you had crew you could easily bump the bow this way or that while backing. As the others say prop walk can be to your benefit in many manuvers. I wouldn't trade the benefits for a boat that could back astern better. Learn to use spring lines to your benefit its simply a matter of time before you're going to need to know how. Like the next time your at the fuel dock 10 feet behind a big ol cruiser and some schmuck in another big ol tub pulls in behind you and the wind is pushing you and holding your boat to the dock. Check out the link.
Its a drag!
Jim I ran a thread on this subject on the "other sailors" forum a few months ago and got a heavy response. My Catalina 30 with its two blade prop shares the same behavior as your boat and I have to walk the vessel "down the fairway" in reverse as a way to clear my dock. At first I thought this was an ackward and even embarassing maneuver. Going backwards down three - four slips to clear my dock? How weird! But, this was re-enforced by many who have to do the same to get out of the dock successfully who are plagued with that port walk problem. Actually, many advised that they turn around with the wheel in hand behind them as they steer down the fairway. I have learned to accept this as standard practice, and who knows, maybe someone from a distance is calling it "genius". The 30 steers beautifully to port in reverse and an occasional switch to neutral and starboard rudder gets em even straight now and then. The only other way is a three bladed prop or bow thrusters! Bob
Jim I ran a thread on this subject on the "other sailors" forum a few months ago and got a heavy response. My Catalina 30 with its two blade prop shares the same behavior as your boat and I have to walk the vessel "down the fairway" in reverse as a way to clear my dock. At first I thought this was an ackward and even embarassing maneuver. Going backwards down three - four slips to clear my dock? How weird! But, this was re-enforced by many who have to do the same to get out of the dock successfully who are plagued with that port walk problem. Actually, many advised that they turn around with the wheel in hand behind them as they steer down the fairway. I have learned to accept this as standard practice, and who knows, maybe someone from a distance is calling it "genius". The 30 steers beautifully to port in reverse and an occasional switch to neutral and starboard rudder gets em even straight now and then. The only other way is a three bladed prop or bow thrusters! Bob
Thanks
A big thanks to everybody that took the trouble to send me their thoughts on this subject. Maybe next Spring I can do a little better. Your experience with backing out from the slips reminds me of several occasions Bob when single handing and with the the wind speed and direction entirely wrong for the job, I backed the whole way to more open water. Fact is that I just didn't have any choice, the boat was NOT going to make the desired turn for me and let me go out bow first. Don't really know why but some of the 'old hands' ( some of who never seem to leave their slips ! ) seemed to frown on the practice. As it got me and the boat out safely however I have to wonder what's wrong with it. Jim G.
A big thanks to everybody that took the trouble to send me their thoughts on this subject. Maybe next Spring I can do a little better. Your experience with backing out from the slips reminds me of several occasions Bob when single handing and with the the wind speed and direction entirely wrong for the job, I backed the whole way to more open water. Fact is that I just didn't have any choice, the boat was NOT going to make the desired turn for me and let me go out bow first. Don't really know why but some of the 'old hands' ( some of who never seem to leave their slips ! ) seemed to frown on the practice. As it got me and the boat out safely however I have to wonder what's wrong with it. Jim G.
- Status