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  #1  
Old 05-14-2010
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Need advice for leaving my slip in strong currents

OK, guys, I could use some help getting OUT of my slip. We have very strong tidal currents on the Delaware river, pushing me directly into or out of the slip. Of course, as I'm coming into the fairway these are strong side currents.

FYI, I have to back into the slip because the finger piers are not long enough, and the freeboard and lack of side decks on the Catalina 250 makes it impossible to board amidships.

For coming into the slip, I start out in the river and determine the throttle level needed to barely make headway into the current going BACKWARDS. I stand in front of the wheel facing backwards and holding the wheel tightly (since the rudder is badly unbalanced going backwards) and my wife sits at the motor and controls throttle/shift. (This is an outboard design with no controls at the pedestal.) Then I approach the fairway backwards. At this speed the boat is "crabbing" badly, since the speed is not enough to swing the boat around into a straight-backwards orientation in the cross-current, so I have her juice up the throttle a bit. Once we get to the slip I do a hard 90-degree turn and immediately throw it in neutral and sometimes hard forward to keep from hitting. A spring line onto an amidships cleat pulls us nicely to the finger pier and prevents us from hitting, but when it's just the two of us we sometimes get too far past the spring line to get it on the cleat - that's when she really throws it into hard forward. However, we've managed to get into the dock every time without any mishaps.

But going out is a much tougher problem. The boat just does not want to turn at slow speed. This is especially bad when we're going with the current out of the slip - we did have a mishap where we had to hold ourselves off of the boat across from us. When with the current, there is just no way to make the turn quickly enough to avoid being carried into the boats across from us - even when we pivot the motor. So I would like your advice on springing out of the slip. This is not as easy as it might appear, because there are no pilings. So I would need to spring from a cleat on the finger pier, which requires a very long spring line, and thus a large turning radius.

There are a couple of possibilities. We could put a spring line on the bow to turn us toward the starboard and proceed out of the marina forward, or we could spring amidships on the port side, swinging the boat to port, then back out of the marina in reverse. The latter would use a shorter spring line and be easier to access since it's amidships. The bow is very narrow and my wife does not like going up there.

Here is a satellite pic of the marina. Our boat is where the white rectangle is located (sorry for my lousy photo editing skills). There are currently more boats across from us than pictured here. Currents go roughly left to right depending on the tide:


Here is a schematic of the slips and boats adjacent to me. You can see that I need to maneuver between a 36' Chris Craft tri-cabin two slips up, and two other boats across from him with very threatening looking bow sprits. You can see that springing to the starboard from the bow will take over 60' of line - 30' from bow to cleat, and 30' back the other way:


Here is a picture of my neighboring boats (on a very dreary evening). You can see that the available cleats are pretty far back on the finger dock:


And finally here is a view looking out toward the river. The bow of my boat is barely visible to the far right - back from the Chris Craft:


I am open to your suggestions.
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Formerly posted as "RhythmDoctor"
1998 Catalina 250WK Take Five (at Anchorage Marina, Essington, on the Delaware River)
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Last edited by TakeFive; 05-15-2010 at 01:33 AM.
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Old 05-14-2010
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RhythmDoctor -
I'm impressed with your ability to get into your slip. When the current is with you when leaving, why not just reverse the process and crab out the fairway with the engine in reverse?
When the current is against you, the boat should turn with a little patience and using the current to help you turn. Just get the boat pointed correctly when you start to leave the slip.
Or maybe I don't understand the situation?
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Old 05-14-2010
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I am not certain that I get this, but the Chris Craft, probably a twin screw, probably has it easier.

I too am impressed that you can get in there as well as you seem to. Anyone with that ability should get out even easier.

Again, not quite sure...but. I would probably attempt a FLOATING line that can loop over a cleat on the end of your peir, around the back of the boat to a starboard stern cleat (mid ships might also work but a longer line) and handled by one of you. As you pull forward take out the slack in that line and apply pressure that will turn the boat to starboard and power you into the fairway when you are clear. Release the line so it slides off the pier cleat and pull it in so that it does not get fouled. Just make sure that you have a fair lead that does not snag on the pier or you will have to practice your return while avoiding that floating line.
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Old 05-14-2010
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Perhaps a spring line on the bow - port side. Since the tide is moving from the stern, let the tide with low power and left rudder take you out of the slip. Keep tension on the spring line until you are bow towards your slip. Then throttle up, left rudder and crab until you get enough hull speed to manuever with your rudder. This probably would require your wife to stand at least midships to retrieve your spring line.

Otherwise, what HP outboard do you have? Also, would a different pitch prop offer more torque for getting more initial hull speed? How do other sailboats pull it off that are facing the same direction?
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Old 05-15-2010
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i agree with tomandchris regarding a line wrapped around the stern from to a starboard boat cleat to a port finger cleat as you exit your slip foreward. BUT ideally one would want to attatch this to a cleat on the boat as far forward as possible, as this will hold the bow against the current while your outboard "catches up" with the lateral movement of the craft and begins to push foreward. if you cleat this line abaft, your bow will only carry currentward and you will be screwed. Just make sure your linesperson slacks & pulls the line after you have acheived foreward motion.
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Old 05-15-2010
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Agree, the farther forward the better, just be sure you clear the boat before taking out slack. With a 25' boat it really should not matter if you have any way on the boat will turn when you snug the line.
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Old 05-15-2010
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For leaving the slip you can spring off your starboard NOW, but what about when that empty slip to strbd has a boat in it? No boat, no problem. I'd would start practicing another method for the eventuality of that slip filling up.

There is a way you can do it without springing. When the tide is with you, coming from astern, the water action against your rudder is going to act the same way as it would when you are engine reversing your boat. In reversing,of course, your rudder points to the direction your stern will go, and opposite the direction your bow will go (not the tilller, mind you...the rudder). The following depends on if your prop is forward of your rudder or abaft your rudder, or off to one side or the other.

Anyway: Leaving slip with the tide: Put your engine in reverse, so that your fairly neutral with the dock but going against the tidal vector. Put the rudder to port (tiller top starboard)..keep your outboard dead astern. Your bow should begin to swing towards strbd because of thew water action on your swung rudder. Gradually ease of on the reverse thrust. and the current will take you forawrd. Your bow should already be pointing slightly towards strbd. Reversing against the current just helps increase the pressure on the rudder. As you know, you don't get a lot of turning initiative when neutral with this current 9none, really). With the current working on your rudder and now your moving forard because of the current, your stern should start swinging to port, initiating your turn. As it's doing this, Put the engine in forward at 1/3 throttle and carry out your turn to starboard. This SHOULD be a fairly controlled turn if everything works out right. Maybe have a few people aboard with boathooks the first couple times you try this.

With the tide against you, just gun her forward into the current and make a big wide arc strbd turn, keeping plenty of distance off that Chris-craft.

Anyway, the point is, the current is often your friend in tight conditions if you use it like a tool.

My boat ihas a long full keel, so it would act entirely differently in that place.

If the wind is strong enough and from right direction, you can also use your jib to swing your bow, and you'll be the envy of the other slip-holders!

How many knots is the tidal current there?

Sorry for ALL the typos, but I had to put my screen viewer at like 60% just to be able to see all of the text, because that picture is SOOO wide! The letters on my screen are now the size of quarks.
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Last edited by SoulVoyage; 05-15-2010 at 12:51 AM.
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Old 05-15-2010
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A couple of things.

With a strong side current, you cannot passage a narrow fairway other than with the boat angled between the current direction and your direction of travel...you need to "crab" in and out. Don't expect to turn 90% and run in or out, the boat will move sideways at the speed of the current and you will run out of fairway.

You should not have a problem turning at low speed, you have the strength of the current working on the rudder, even if the boat has no headway.

You need to enter your slip differently than other boaters. Set up outside the fairway directly into or against the current (depending on how you want to enter the slip) by adjusting the throttle so the boat stops directly in front of the fairway. With the correct throttle you should stay perfectly still. Then adjust your rudder so the boat turns 5-10% towards the fairway, and adjust the rudder back so the boat holds that angel, adding more throttle as needed to stay in the center of the fairway. Let the boat slowly crab up the fairway until you are at your slip. Apply rudder again straighten the boat into the current, then slightly increase/decrease throttle so boat slowly moves into the slip. Tie up.

Just get used to the idea of moving sideways up and down the fairway, use the current for rudder control, and adjust the location lf the boat only by throttling just above or below the current speed.

Sounds like fun.

PS - successfully turning the boat 90 degrees into the fairway will deliver you into a world of hurt...
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Last edited by sailingfool; 05-15-2010 at 12:58 AM.
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Old 05-15-2010
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Thanks for the suggestions, everyone. I am going to have to draw out some of the mechanics on paper to make sure I fully understand, and then get back to you with any questions. (Sorry, it's an engineer thing about me - it always has to be a picture.)

I mis-described my docking maneuvers somewhat. Rather than a sharp 90 degree turn, right now it actually is more gradual. As soon as I get past the bow of that Chris Craft far enough to see into my slip, I start to make the turn into my slip - a little more gradually than I described. This will work great as long as that slip next to me continues to be vacant. If they put someone in there, it is going to get mighty tough to make the turn sharp enough without creating way too much rotational inertia in my boat. The owner of the Chris Craft told me that the slip next to me was vacant last year, so I can hope it may stay that way this year - we'll have to see. Hopefully that Chris Craft is so imposing that nobody wants to dock next to it. He'll be looking right down into their cabin. (And mine, but I have factory window shades.)

My relative success in docking has made my difficulties leaving the slip even more frustrating.

BTW, the Chris Craft (which may actually be 33 or 35') is actually a single screw. The owner has two boats in this marina (and several in other marinas). They use the Chris Craft as a floating condo that never leaves the dock, and they have a Donzi (or something similar) two slips down that they use for joyriding.

Quick answers to other questions:
  • I am not sure exactly how fast the current is. NOAA lists typical peak currents of 1.4-2.0 knots, but I am not sure where their sensors are relative to the marina. Ulladh keeps his boat at a nearby marina and says he has clocked it up to 6 knots, but there's no way I'll attempt to go out when the current is at hull speed.
  • This boat has a 15 hp Honda outboard, which is about double what's needed to achieve hull speed. Most Catalina 250s have 8-9.9 hp. But that extra power may come in handy in the currents.

I just saw SoulVoyage's suggestion, and I have been thinking similarly. When the current is pushing me out of the dock, I might be able to find a slow reverse speed that carries me out of the dock very gradually, and maintains good (negative) speed over water so I have good rudder control (just in the opposite direction from what I'm used to). However, the part about turning the bow to starboard, then going into forward scares me. I know from the limited experience that I have that shifting the motor from reverse to forward will make me momentarily lose control, and the currents could be enough to get me in trouble at that point. (That's why I back in all the way from the river - so I don't have to change direction on the way in.) So I'm actually thinking of turning the bow to port (stern to starboard) with the motor in reverse, then once my stern is clear of the slip and the Chris Craft, throttle up in reverse and back out of the fairway. This way I always have good speed relative to water, and don't need to worry about losing control. Because of the direction that my boat would crab in the side-current, this would also require slightly less than a 90 degree turn. But the major negative of this is the instability of the rudder in reverse - I would absolutely have to stay at the pedestal the whole time and keep both hands firmly gripped on the wheel. I could not leave the wheel if we needed extra hands to hold off another boat, grab a boat pole, etc.
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1991 15' Trophy (Lake Wallenpaupack)
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  #10  
Old 05-15-2010
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Sailingfool - I just saw your note after posting my response. What you described is exactly what I am doing for docking when the tide is pushing me away from the slip. With the tide pushing me into the slip it gets hair-raising, because in order to maintain some SOW for rudder control, my SOG is pretty fast. But we've been able to stop without hitting the dock, especially when we have a third hand onboard to get the breast lines cleated quickly. So far, entering the fairway and docking has not been a problem.

But it's leaving the dock that has been problematic.
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Formerly posted as "RhythmDoctor"
1998 Catalina 250WK Take Five (at Anchorage Marina, Essington, on the Delaware River)
1991 15' Trophy (Lake Wallenpaupack)
1985 14' Phantom (Lake Wallenpaupack)

Last edited by TakeFive; 05-15-2010 at 01:34 AM.
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