Anyone have any practical experience using an anchor as an aid for maneuvering?
[QUOTE=Kennebec Captain;134087]Anyone have any practical experience using an anchor as an aid for maneuvering?[/QUOTE]
This guy does.
The best ship handler (and quite the character) I’ve seen was Captain Valenzuela, a pilot in Santa Marta Colombia. In the '70s, their 1K hp harbor tug was broke down most of the time. All docking was done with an anchor. I’ve seen him do some amazing maneuvers during the windy season.
Sure. I have done it a few times at least, but I am usually dealing with ground tackle that is on a scale a person or two could pick up. Not sure how it would translate into a multi-ton anchor.
Here is one example:
Headed downwind and downcurrent towards a closed drawbridge and needed to tie up to a wharf near the bridge parallel to the channel. We dropped an anchor over the bow and let the line pay out until we reached the wharf and snugged it off. The anchor dug in and we swung 180 degrees into wind and current and a little rudder swung us right to the pier and held us there while the crew stepped of and tied us up 
I see no reason this couldn’t scale up except the scale if the mess if it goes wrong :eek:
- On the ICW a stern anchor is not uncommon as an emergency brake or way to hold upstream of a bridge
[QUOTE=yacht_sailor;134106]Sure. I have done it a few times at least, but I am usually dealing with ground tackle that is on a scale a person or two could pick up. Not sure how it would translate into a multi-ton anchor.
Here is one example:
Headed downwind and downcurrent towards a closed drawbridge and needed to tie up to a wharf near the bridge parallel to the channel. We dropped an anchor over the bow and let the line pay out until we reached the wharf and snugged it off. The anchor dug in and we swung 180 degrees into wind and current and a little rudder swung us right to the pier and held us there while the crew stepped of and tied us up
I see no reason this couldn’t scale up except the scale if the mess if it goes wrong :eek:
- On the ICW a stern anchor is not uncommon as an emergency brake or way to hold upstream of a bridge ;)[/QUOTE]
Small ships without bow thrusters do it routinely in some ports in in the Med and Asia. Drop the offshore anchor as they approach the berth and when leaving heave on the anchor to pull out the bow.
The preferred way to moor to a jack up up rig, pre DP. Nothing special.
[QUOTE=Steamer;134089]This guy does.
This is another good example of a Captain using the anchor. He uses the anchor to pivot on in both ports they run into on Lake Michigan. Fun watching him ring up the orders to the engine room in some of the other videos of the SS Badger.
Pretty cool displays of skill, other than that anchor being dropped in the tug!
Just curious, with high tech azimuth pods available why don’t more ships have them? Seems like in the unlimited tonnage world they are only mainstream for cruise liners (and maybe DP related vessels??). Is there a reason for this? Seems like it would be beneficial in situations like those discussed on this thread.
if I had to guess:
Azimuth pods are expensive. Tugs are cheap. Cruise ships might be docking every day and would pay a ton in tug charges, but cargo ships dock every week or every month or maybe less.
[QUOTE=MandolinGuy;134122]Pretty cool displays of skill, other than that anchor being dropped in the tug!
Just curious, with high tech azimuth pods available why don’t more ships have them? Seems like in the unlimited tonnage world they are only mainstream for cruise liners (and maybe DP related vessels??). Is there a reason for this? Seems like it would be beneficial in situations like those discussed on this thread.[/QUOTE]
We can say that dredging anchor to go alongside is an art more appropriate to smaller and less powerful coastal vessels. The nature of seabed is of paramount importance. The berthing area must be clear of underwater obstructions. There must be adequate under keel clearance. The cable & anchor are relatively reliable but the windlass is not. We have to remember that a windlass is certified to lift the anchor and 4 shackles hanging dead in the water. The kinetic energy of a vessel moving ahead can be much higher of the design windlass specification thus damage could result.
The scope should not be much more than 1½ water depth, max 2. The speed of the vessel should not be much more than the windlass capability which is 30 feet per minute or ½ a knot max. We have much better control of the scope needed when we walk out the anchor in gear instead of letting go. There is a very fine line between success or failure. Do not let the speed to build up but if you stop the vessel the anchor will dig in, it will be then difficult to get underway again and you could sheer out of position. Walk the anchor early to get the feel.
We will have much better heading and speed control by using the 2 anchors. The pivot point will remain in the center instead of on the side that will create a turning moment. If a large turn is needed prior berthing, then 1 anchor is better.
Some ports do not allow keeping the anchor down while alongside. Fire vs. emergency towing. Tie up the vessel as further ahead with a short head line, a long fore spring, a short back spring and a long stern. Back up on the lines and engine if needed then heave up back the anchor while in position. One stone two birds.
I have experienced:
- 2 times 8 shackles in the water instead of 1 due to break failure and/or forward crew uncaring !
- ‘‘discontinued’’ sub electric cable badly twisted in the flukes … very scaring !
- huge stone stuck in the flukes !
- an anchor D shackle to part and losing the anchor away !
… hooray for the tug !
[QUOTE=Kennebec Captain;134087]Anyone have any practical experience using an anchor as an aid for maneuvering?[/QUOTE]
Used port anchor coming into Cabo San Lucus on a 210’ CG cutter. Let out half a shot then dredged anchor to bring the ship stbd side to the pier. Worked well. Twin screwed it around the anchor. Not much room in there. And then we got flashed by some girls gone wild on a party boat. Ahh Mexico…
So that’s where our national deficit is coming from… USCG weekends in Cabo San Lucas…
[QUOTE=Quimby;134162]Used port anchor coming into Cabo San Lucus on a 210’ CG cutter. Let out half a shot then dredged anchor to bring the ship stbd side to the pier. Worked well. Twin screwed it around the anchor. Not much room in there…[/QUOTE]
When I see it done in Asia (and other places) on coastal vessel there was not much dredging * involved. Instead the anchor is used to make a tight turn.
For starboard side to, the berth is approached broad on the port bow, the port anchor is let go then the ship continues to approach the berth while the mate on the bow pays out the chain “checking” the bow thus greatly reducing the turn radius. The anchor is left down to assist when it’s time to leave.
In the # 2 post by Steamer the ship is attempting a Med moor (stern to the pier) They are using the anchors to moor, in which case they want minimum dredging but they are also using the anchor to assist in the turn in which case some dragging in inevitable. This is similar to what I’ve seen done while mooring alongside (not Med moor) in Asia.
The dredging method described up thread, where an anchor is put down at a considerable distance from the berth and the engine is used against the anchor to slow and control the ship is also the technique described in "Shiphandling For The Mariners by MacElrevery. I have never seen this method used.
[QUOTE=Quimby;134162] And then we got flashed by some girls gone wild on a party boat. Ahh Mexico…[/QUOTE]
Good seamanship can sometimes be very rewarding.
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- Dredging (an anchor)
A term when used in conjunction with an anchor, it means the deliberate dragging of an anchor when at short stay, over the ground of the sea bed.
[QUOTE=lm1883;134179]TopSails advice about walking out the anchors is clutch. Some ships will really pull to the anchor side, some not so much. I have been considerably faster than .5kts though (1 to 1.5).
One shot on deck to one in the water has seemed to work best. Once you get the scope you need tighten the brake up to relieve stress on the windlass, but leave it engaged. If left on the break alone, the chain may run, then things get pretty complicated. Enough may run to where a size able engine bell may not give you forward movement, or the chain could run completely out.
You can use a thruster when dredging an anchor, and it can be effective. Counter intuitive to use the hook when your thruster works, but there are instances where this makes sense. Arresting headway while working your stern alongside is one. If you leave the anchor down alongside, pick it up backing out, or heave on it to pull the bow off.
Dredging is particularly handy in a small or crowded anchorage. That’s probably the best situation to try the evolution.[/QUOTE]
Good info.
I’ve been putting out a short stay when anchoring to swing the bow into the wind before I pay out the rest of my chain. Also a couple years ago I had to anchor with no engine or bow thruster in 15-20 kts of wind on the beam. Swinging the bow around on a short stay worked good.
Dredging ahead in an crowded anchorage is exactly what I’ve been thinking about. MacElrevey is not much help.
The speeds you mention seem right to me.
This thread has been way too cordial for way too long. Anyone want to say something about someone else’s mother? Sister perhaps? Just a suggestion.
Two important factors are the condition of the anchor windlass and the skill of the mate. You definitely don’t want to run out too much chain and have the anchor dig in.
One dark and stormy night when I was sailing mate in Alaska I let the anchor go while we were running down wind. I thought we were going a little too fast but I figured the captain knew what he was doing. I ran out 4 shots ( all the useable chain we had) and tightened the brake. When the chain came tight that little ship spun around like a top.
Next morning we couldn’t get the windlass work as the gears had been tweaked. We pulled the anchor with the cargo gear.
[QUOTE=PaddyWest2012;134163]So that’s where our national deficit is coming from… USCG weekends in Cabo San Lucas…[/QUOTE]
They always gave us one nice port call, but typically worked out of Puerto Quetzal. Does it still smell like dead bodies and have lots of trash in the water?? In any event, you aren’t far from the truth. Burning holes in the ocean looking for drug smugglers is a waste of tax payer dollars.
[QUOTE=Kennebec Captain;134171]When I see it done in Asia (and other places) on coastal vessel there was not much dredging * involved. Instead the anchor is used to make a tight turn.
For starboard side to, the berth is approached broad on the port bow, the port anchor is let go then the ship continues to approach the berth while the mate on the bow pays out the chain “checking” the bow thus greatly reducing the turn radius. The anchor is left down to assist when it’s time to leave.
In the # 2 post by Steamer the ship is attempting a Med moor (stern to the pier) They are using the anchors to moor, in which case they want minimum dredging but they are also using the anchor to assist in the turn in which case some dragging in inevitable. This is similar to what I’ve seen done while mooring alongside (not Med moor) in Asia.
The dredging method described up thread, where an anchor is put down at a considerable distance from the berth and the engine is used against the anchor to slow and control the ship is also the technique described in "Shiphandling For The Mariners by MacElrevery. I have never seen this method used.
Good seamanship can sometimes be very rewarding.
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- Dredging (an anchor)
A term when used in conjunction with an anchor, it means the deliberate dragging of an anchor when at short stay, over the ground of the sea bed.[/QUOTE]
I misused the word although the anchor probably did dredge some, it was technically a pivot maneuver. Once the turn was completed, the anchor was brought to the water’s edge. There is an interesting article about the SS Badger in the Feb. Professional Mariner. The last coal fired ferry uses their stbd anchor to pivot the stern to the dock and then dredge the anchor until they are notched up.
[QUOTE=lm1883;134190]TopSail — when you are maneuvering with 2 anchors what kind of bells are you using? What type of ships are they?[/QUOTE]
The first time I ever used 2 anchors was in the course of a Manned Model Ship Handling module. I then used the method on a reefer equipped with a powerful reversible diesel engine with not so many starts, a minimum speed of close to 7 knots , needed to appoint within a very small angle due to the extensive bow flare, berthing starboard side alongside with a right handed propeller and to make it easier, along with a pushing wind in an eddy current ! Finally, I had to recover both anchors back on board. It worked fine but I name these type of manoeuvres ‘‘Aquatic Ballet’’.
I dredged an anchor once going all the way backward into a far away narrow basin. I had to go around 2 tie up vessels one on each side. The crew was running on deck with flying fenders. Extremely difficult to back a vessel. When we were finally fast after summit efforts and sweat, I asked the captain if it was the worst manoeuvre that he ever seen. He told that everything went fine. Can you imagine how it looked when it was not going well !