Cooper Island - backwinding visualized

It's been about 10 years since we've been to Cooper Island, so we recently gave it another shot. Armed with a boatyball reservation (my first), we planned to eat dinner ashore. But, we caught a sizeable mahi en route, so we cancelled the dinner res. The resort is nice, and we enjoyed a drink at the rum bar and a game of cricket. But, I really don't see the appeal of this mooring field. There are more scenic anchorages and I really didn't care for the current / backwinding effects. Will probably be my last visit.

I took this time lapse over 6 minutes. Really helps to visualize how almost every boat is moving in another direction. Tried to post here as a gif, but it's too big, so here's the YouTube link.

Bonus shot of our mahi:

Great timelapse and beautiful fish. Thanks for sharing.

Nice fish! We avoid Cooper. So many other anchorages to visit.

We spent our last night out at Cooper, and while it wasn't the calmest night, neither of us is much bothered by the bouncing around. We were on an outside mid-field ball which was probably a bit rougher, but we didn't spin around.

I chose Cooper over Norman (which would have been calmer), because instead of a bash to windward we had an easy beam reach back to Road Town.

An M5000 (Sea Sprite) took a mooring near us and tied up with a single line through the pendant eye fastened to the crossbeam cleats.
I try to avoid involving myself, but ended up dinghying up to them and after apologizing for the intrusion and asking if they were the owners of the boat, I said I wanted to make sure they knew that this was not an adequate tie-up.

They did (kind of) correct the situation, but saw the boat back at the base yesterday, so I have to assume that they tied up in that manner for all but the last night of the trip. :-(

Cooper is where the Sunsail boat broke free and grounded on Dead Chest Island. Was there ever any verdict on the cause? Did they use one line as you describe or did the ground tackle fail? Ironically, the Lagoon 51 we were on last week is the owner's new boat.

The word is that the Sunsail boat that "broke free" and grounded had charterers who used the anchor bridle hook to hook up to the mooring ball at Cooper.

Last trip I saw a cat using the anchor bridal in CDB. I routinely see the one line method. I really hate that because even if they don’t break free over time it ruins the eye of the mooring pendant. It just doesn’t take that long to properly rig two lines.

I saw a lot of boats using the crossbeam cleats, which isn't as strong as a connection to the hull cleats.

We've used the cross beam cleats for years under normal conditions without any issues. I know the placard warns not to. We found that the lines tend to squeak as they rub against the hull (annoying when sleeping in the forward cabins).

I only use the crossbeam cleats as fairleads. It keeps the bridle just as organized but puts the load where it belongs.

The crossbeam cleats will be fine in most situations, but if they are not the consequences could be pretty bad (loss of rig).

You never know what load the lines might have to take... a bigger boat upwind could come loose and drift down on you. Or some idiot could just run into you. Normal conditions can turn into abnormal conditions without warning.

We do the same with crossbeam cleats...use as fairleads. We have one end tied on the side cleat and then run through the crossbeam cleat to the mooring eye and then back to the crossbeam cleat and tie the other end on it making sure not to bind the line running through the crossbeam cleat. anyone see any issue i should know?

I run my lines from the side cleat to the ball and back to the cross beam cleat. Cuts the load in half on each cleat and makes it easier to tie off on each one. The crossbeam cleats I was told are fine up to 60 knots of wind. There have been some issues when people tried to get pulled off reefs via the crossbeam cleats.
One small point on the lines used for mooring. They should not be able to reach back to the props if one end fell in the water.

This makes a lot of sense, an improvement I'll make on our next trip.

I've been mooring at Cooper Island since the 90's. It is always "shifty" there as the wind curls over the top of the hill and swirls around the mooring field.
I hate it when the boat runs over the mooring ball and it bangs against the inside hull (catamaran) all night long.
But, the snorkeling there is usually good and it's a good hopping off spot to head to The Dogs, or Baths or even Leverick.

So, I run the mooring pennant almost to the starboard cleat, tied with a short line. On the port side of the boat I run a line from the cleat directly to the eye on the ball itself. This - at least - stops any banging in the middle of the night against the sides of the hull under the cat - and it leaves us on 2 separate lines. Hard to explain, but the boat has much less unusual motion...

That’s exactly how I tie up at Cooper or other places where backwinding is likely. Not only do you have a quiet peaceful night but it minimizes your swinging room. Nothing worse than something pounding your stateroom like a bass drum!

Not arguing with your logic of using the crossbeam cleats as fairleads, I can see how this keeps the lines in the right place and not bearing on handrails etc. I'm fairly inexperienced with cats and mooring balls but I thought the whole point of using a bridle was to keep the two lines wide apart to reduce swinging? By using the narrower cleats as fairleads you are transferring the fulcrum points inboard quite a bit or is it not enough to make a difference? Interested to learn from others knowledge.

I have not found any noticeable difference between how the cat rides at anchor. I often shorten the lines in places like Cooper where spinning and crowding are an issue. Short enough so the bridle rides over the ball rather than hooking it if it goes slack, and I still don't notice a difference.

One of the toughest places to moor is St. Augustine on the Matanzas River. Often very strong current -v- wind conditions are present. We were there for a long stay and learned to shorten each bridle leg and use a center line tied off to one of our catwalk cleats. For us it has worked well and we use the method often. We position fenders between our mooring lines and the boat and run our mooring lines over the fenders. The fenders act as shock absorbers and also virtually eliminate squeaky lines as they no longer rub against our hulls.

Great conversation! I like the idea of using the crossbeam cleats as a fairleads. If that geometry doesn't work out (ie life line stanchion gets in the way) using fenders to reduce line squeaking/rubbing against the hull is a great idea as well.

Since the issues with the ball banging the hull at Cooper come up often here is a quick sketch of the method to stop the noise in low or no wind conditions. It traps the ball so it can’t reach the other hull. I don’t recommend this in other than light winds. You may need to use the dinghy to route the dock line to the ball and back.