I have a Beneteau 361, 27 hp (year 1999). My boat is shifting seriously to the port side when I start the rear maneuver and I can't command the boat until she gets the speed. This is a big problem for me in the marinas. If I use the thruster can I solve the problem or do you reccommend another solution?
Rear maneuver
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prop walk
When backing out of a slip, you need to consider prop walk. This is a phenomenon of all single prop boats. It has to do with the density of the water above and below the prop shaft and the angle the prop is to the boat. also you need to know that the boat has to be moving for the rudder has any effect to copinsate for the prop walk. Some power boats have counter rotating props to nullify this phenomenon. Airplanes props have this same problem called "asymmetrical pitch loading" This is a characteristic of your boat and you will need to know how your boat will respond to backing up. Talk to some other boaters with large boats to get some tips on how to handle this phenomenon. Practice backing in both directions and learn how to compensate for each direction in reverse. Keep sailing. AL
When backing out of a slip, you need to consider prop walk. This is a phenomenon of all single prop boats. It has to do with the density of the water above and below the prop shaft and the angle the prop is to the boat. also you need to know that the boat has to be moving for the rudder has any effect to copinsate for the prop walk. Some power boats have counter rotating props to nullify this phenomenon. Airplanes props have this same problem called "asymmetrical pitch loading" This is a characteristic of your boat and you will need to know how your boat will respond to backing up. Talk to some other boaters with large boats to get some tips on how to handle this phenomenon. Practice backing in both directions and learn how to compensate for each direction in reverse. Keep sailing. AL
One maneuver
Ersin, There are many ways to cope with this. One that I have used is to go forward against the bow spring line until it kicks the stearn out. Then go into reverse.It is kind of like hedging your bet. It gives you a small distance to compensate for the propwalk (caused by the direction of rotation of the propeller)while putting on stearnway (headway backwards). One common error is to turn the rudder too far to starboard before you get stearnway. The rudder then stalls and has no effect. r.w.landau
Ersin, There are many ways to cope with this. One that I have used is to go forward against the bow spring line until it kicks the stearn out. Then go into reverse.It is kind of like hedging your bet. It gives you a small distance to compensate for the propwalk (caused by the direction of rotation of the propeller)while putting on stearnway (headway backwards). One common error is to turn the rudder too far to starboard before you get stearnway. The rudder then stalls and has no effect. r.w.landau
Another Trick
Ersin, Try untying all mooring lines except one. Have this on a slip ready to let go quickly. Then engage reverse and build up engine revs whilst still attached to your dock. You will see water being dragged under the boat as if she were ALREADY moving backwards. Now reduce engine revs and let go. If done quickly the resultant water flow across rudder and keel might just get you under control. It will need a little experimenting to find the best shoreline to leave attached
Ersin, Try untying all mooring lines except one. Have this on a slip ready to let go quickly. Then engage reverse and build up engine revs whilst still attached to your dock. You will see water being dragged under the boat as if she were ALREADY moving backwards. Now reduce engine revs and let go. If done quickly the resultant water flow across rudder and keel might just get you under control. It will need a little experimenting to find the best shoreline to leave attached
Experiment with throttle
If you were a power boater before sailing you have some bad habits to correct or change. In power boating it is just that. Power can overcome any problem. With sail boats that is untrue. I would practice in open water a couple times to see how the boat responds to different throttle speeds to see which one is more effective. Remember that the keel acts on the steering also and that you can pivot around it unlike a power boat. In an outboard if the throttle is not on, you can turn the motor to change direction. then power it up. In a sail boat, if you have head way or stearnway, as soon as you turn the rudder you turn in that direction pivoting around the keel.If you are pulling into a slip between pilings and you miss the first shot so you want to back out. The first thing you do is put it in reverse and wait until the boat starts to move backwards, then turn the rudder. If you turn the rudder before that it will make your problem worse. I know this might sound irrelevant, but I don't know you and your experience so I would rather fault on the side of too much info. r.w.landau
If you were a power boater before sailing you have some bad habits to correct or change. In power boating it is just that. Power can overcome any problem. With sail boats that is untrue. I would practice in open water a couple times to see how the boat responds to different throttle speeds to see which one is more effective. Remember that the keel acts on the steering also and that you can pivot around it unlike a power boat. In an outboard if the throttle is not on, you can turn the motor to change direction. then power it up. In a sail boat, if you have head way or stearnway, as soon as you turn the rudder you turn in that direction pivoting around the keel.If you are pulling into a slip between pilings and you miss the first shot so you want to back out. The first thing you do is put it in reverse and wait until the boat starts to move backwards, then turn the rudder. If you turn the rudder before that it will make your problem worse. I know this might sound irrelevant, but I don't know you and your experience so I would rather fault on the side of too much info. r.w.landau
The nature of sailboats
Ersin, I am assuming this boat is new to you, and you are getting familiar with the performance. Get to know the nature of your boat, the dynamic relationship between the hull, prop, keel, and rudder, and your hand on the throttle. Go out in open water, experiment with the throttle and transmission, learn the nature of her propwalk, what to expect, and how to handle it. You can't change the nature of the boat, you just need to learn how to handle it. Sorta like women <G>
Ersin, I am assuming this boat is new to you, and you are getting familiar with the performance. Get to know the nature of your boat, the dynamic relationship between the hull, prop, keel, and rudder, and your hand on the throttle. Go out in open water, experiment with the throttle and transmission, learn the nature of her propwalk, what to expect, and how to handle it. You can't change the nature of the boat, you just need to learn how to handle it. Sorta like women <G>
Practice, practice, practice
Prop walk is indeed something sailors with auxiliary engines have to learn to manage, and it takes practice. One good suggestion (below) was to go out into open water, and take time to stop, back, maneuver, etc. You'll need to do this to anchor successfully anyway, with or without wind, and it will help get you started on managing the effects of prop walk. Go slow. Other ideas: --At the dock, tie the boat securely and put it into reverse at low RPM. Look over the starboard side and you'll see what is happening as the water pushes you sideways to port and the water rushes to the starboard, not straight forward.. -- Make adjustments to the boat position in your slip as you prepare to back up; i.e., position the boat as far to starboard as possible. -- Use your dock lines , particularly your starboard stern line, to control position as you start. -- Use minimal power at first, and avoid trying to add power to correct problems, as the opposite will happen. That awful sound will be fiberglass crunching. -- Try a small burst of power in reverse, and back off to idle rpm until the boat is moving backward; -- Once the boat is under way, you have better rudder control, and then you can add power, but be sure and use it sparingly. Once the boat is moving 1-2 knots or so, the rudder will bite adequately to control direction and water flowing over the keel will overpower the prop walk. Most important of all? Use lots of fenders when practicing. :>) Good luck. p.s. Count me as a Hedo Turkolu fan.
Prop walk is indeed something sailors with auxiliary engines have to learn to manage, and it takes practice. One good suggestion (below) was to go out into open water, and take time to stop, back, maneuver, etc. You'll need to do this to anchor successfully anyway, with or without wind, and it will help get you started on managing the effects of prop walk. Go slow. Other ideas: --At the dock, tie the boat securely and put it into reverse at low RPM. Look over the starboard side and you'll see what is happening as the water pushes you sideways to port and the water rushes to the starboard, not straight forward.. -- Make adjustments to the boat position in your slip as you prepare to back up; i.e., position the boat as far to starboard as possible. -- Use your dock lines , particularly your starboard stern line, to control position as you start. -- Use minimal power at first, and avoid trying to add power to correct problems, as the opposite will happen. That awful sound will be fiberglass crunching. -- Try a small burst of power in reverse, and back off to idle rpm until the boat is moving backward; -- Once the boat is under way, you have better rudder control, and then you can add power, but be sure and use it sparingly. Once the boat is moving 1-2 knots or so, the rudder will bite adequately to control direction and water flowing over the keel will overpower the prop walk. Most important of all? Use lots of fenders when practicing. :>) Good luck. p.s. Count me as a Hedo Turkolu fan.
Switch to an Autoprop
We also have a 1999 361 and put an Autoprop on 3 years ago. The propwalk is essentially gone and picked up 3/4 knot speed under both sail and power.
We also have a 1999 361 and put an Autoprop on 3 years ago. The propwalk is essentially gone and picked up 3/4 knot speed under both sail and power.
Boat Handling Advice
Some good advice on boat handling, and prop’ walk: http://cruisersforum.com/showthread.php?s=&threadid=1462 A Thruster would be overkill on any sailboat under about 50 to 60 Ft. Gord May
Some good advice on boat handling, and prop’ walk: http://cruisersforum.com/showthread.php?s=&threadid=1462 A Thruster would be overkill on any sailboat under about 50 to 60 Ft. Gord May
Here's what I do
I have a Hunter 356, which has some similar tendencies. I went out and practiced in calm water, repeatedly coming up to and backing away from a mooring bouy until I found something that worked. For me, for backing, it's this: With the boat at rest, put the wheel over one-third turn to stbd (i.e., rudder also to stbd). Goose the engine to get some way on, but not steady throttle. The rudder offsets the propwalk. Once the boat is moving astern, I use the rudder in the normal fashion. At least in our boat, the key seems to be avoiding sustained power bursts until there is sufficient steerage way. Hope that makes sense. My main recommendation is, as others indicated, to get out in a place where you have plenty of room and practice with different combinations of power and rudder until something clicks.
I have a Hunter 356, which has some similar tendencies. I went out and practiced in calm water, repeatedly coming up to and backing away from a mooring bouy until I found something that worked. For me, for backing, it's this: With the boat at rest, put the wheel over one-third turn to stbd (i.e., rudder also to stbd). Goose the engine to get some way on, but not steady throttle. The rudder offsets the propwalk. Once the boat is moving astern, I use the rudder in the normal fashion. At least in our boat, the key seems to be avoiding sustained power bursts until there is sufficient steerage way. Hope that makes sense. My main recommendation is, as others indicated, to get out in a place where you have plenty of room and practice with different combinations of power and rudder until something clicks.
Backing and Filling......
go to http://www.videos.sailingcourse.com/pivot_turn.htm for a descriptiion of the "pivot turn". Once you master this technique you will WANT prop walk to help you steer the boat in reverse. When adding 'throttle' be sure to give quick and Powerful 'blasts' with the throttle. Just short, quick, and high powered 'blasts' of the throttle to help kick the stern to the portside to help steer. Once you get water flowing across the rudder then you can idle in reverse and keep a fairly straight course. Practice practice and more practice.
go to http://www.videos.sailingcourse.com/pivot_turn.htm for a descriptiion of the "pivot turn". Once you master this technique you will WANT prop walk to help you steer the boat in reverse. When adding 'throttle' be sure to give quick and Powerful 'blasts' with the throttle. Just short, quick, and high powered 'blasts' of the throttle to help kick the stern to the portside to help steer. Once you get water flowing across the rudder then you can idle in reverse and keep a fairly straight course. Practice practice and more practice.
Pivot turn reality
Very nice video. Now add 20kts of wind and some current! I would love to see that demonstrated in a crowded marina! Tim R.
Very nice video. Now add 20kts of wind and some current! I would love to see that demonstrated in a crowded marina! Tim R.
Prop' walk is your best tool
I had a difficult time composing my reply (previous link to Cruiser Forum), because the maneuver(s) have become so intuitive. I had to really think about exactly what it was I have been doing. I am mechanically challenged, and suspect that, if it can become second nature to me - then anyone can become expert with practice. The key to close quarters maneuvering is PATIENCE & PRACTICE! No matter how difficult wind, current, & other traffic might make turning your boat - it is always easier with prop’ walk. Of course, in trying conditions, you may have to increase power slightly (bursts at shift), and lead your target some (allow for offsetting forces), but the practice you got under more benign conditions will stand you in good stead, when the going gets more difficult. FWIW, Gord May
I had a difficult time composing my reply (previous link to Cruiser Forum), because the maneuver(s) have become so intuitive. I had to really think about exactly what it was I have been doing. I am mechanically challenged, and suspect that, if it can become second nature to me - then anyone can become expert with practice. The key to close quarters maneuvering is PATIENCE & PRACTICE! No matter how difficult wind, current, & other traffic might make turning your boat - it is always easier with prop’ walk. Of course, in trying conditions, you may have to increase power slightly (bursts at shift), and lead your target some (allow for offsetting forces), but the practice you got under more benign conditions will stand you in good stead, when the going gets more difficult. FWIW, Gord May
pivot turn
You get more oomph in the pivot turn if you put your rudder over when backing. In the example, flip the rudder to port when making sternway or using reverse engine. Provides more control in windy conditions as well. Practice, because it can bring the bow around surprisingly fast.
You get more oomph in the pivot turn if you put your rudder over when backing. In the example, flip the rudder to port when making sternway or using reverse engine. Provides more control in windy conditions as well. Practice, because it can bring the bow around surprisingly fast.
Anticipation
Ersin, I wonder what maneuver you are trying to do in reverse in the marina? If you are "med mooring" stern first, after dropping the anchor, or picking up a mooring ball, then you want to anticipate the prop walk to port by aiming the boat with its stern to starboard as your drop the anchor. Then when you gun the boat in reverse bursts, the swing to port will line you up with the place on the dock you are aiming for. I agree with the other advice for practice, and other compensation. The basic advice is to learn how your boat handles, and include that in your maneuvering plan so that you anticipate it, and make it work for you. Best regards, David
Ersin, I wonder what maneuver you are trying to do in reverse in the marina? If you are "med mooring" stern first, after dropping the anchor, or picking up a mooring ball, then you want to anticipate the prop walk to port by aiming the boat with its stern to starboard as your drop the anchor. Then when you gun the boat in reverse bursts, the swing to port will line you up with the place on the dock you are aiming for. I agree with the other advice for practice, and other compensation. The basic advice is to learn how your boat handles, and include that in your maneuvering plan so that you anticipate it, and make it work for you. Best regards, David
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