Has anybody ever had the experience of having to sail up a channel and maybe under a bridge where the tidal current AND the wind are both against you?

I experienced this last weekend, and it was definitely a character-building experience. For the first time I understood firsthand how easy it would be for a disabled boat -- power or sail -- to be swept out to sea on an outgoing current where a lot of water has to get in or out through a relatively narrow slot.

I know some of you have to deal with this situation all the time, but most of us do not. So what is the secret to making progress when the current is taking you back faster than you are making progress forward?

I had a paddle, but it was the first time I ever wished I had an outboard motor on the back of my boat.

And I won't even go into the problems we had trying to round the weather mark because of the current even three or more miles offshore. Reminded me of a videotape I have seen of a major Laser championship where, in some cases, it took the boats three or more attempts to get around the weather mark because of current. It was humorous to watch, but less so when it is happening to you personally.

Please share your nightmares with current and tips for coping with the situation.

On the second day of the Steeplechase the racers can either follow the Intracoastal Waterway or take short cuts across mangrove patches or mudflats (thus the name Steeplechase where in Merry Ole England the race was from the start line to the Steeple that was visible above the trees -- any route that you wanted to take, be it over fences, bushes, through creeks, or whatever).

However, for the Key Largo Steeplechase, there is still two obstacles that must be addressed and there are two options:
1) Sail deeper into the Bay and more westerly and then go through a narrow creek in the mangroves called the Bogies. Out of the past 18 years, twice this route was used to take a victory. It is very narrow (about 4 boat widths wide) and if the current and wind are against you, you are doomed. No room to tack or anything. Paddling is the only answer, but not a very good one.
2) The Intracoastal has two magrove creeks to navigate to get to the wide open waters of Blackwater Sound and the last 4 miles to the finish line. The first creek is not too long and not bad to navigate, but Dusenberry Creek is quite long.
No matter which way the wind is blowing when you enter Dusenberry the wind is on the nose all the way through the creek. And the current is also usually against you.
Now, the creek is about 50 or 60 feet wide which allows you to tack up the channel. But how you do this is pretty important.
First, the current in the middle of the creek is much stronger than the current at the side of the creek (where there is much friction and often even some eddies that will help you upstream a bit. So, this tells you that you want to stay near the sides of the creek as much as possible.
Next you need to know about the "Rule of 90" where wind likes to cross a land-water area at 90 degrees. Howevever, with this small an area, it will not make it, but it still will try to head into the mangroves at some degree.
This means that if you can stay near the sides of the channel you will get a lift from the wind (albeit you will certainly have to pinch to stay there) and you will have a much slower current against you.
So, the secret is to rush across the middle with full speed and when you reach the other bank sheet in hard and pinch along the bank.

I have passed this little gem along to most of the sailors in the race, but most seem to forget about it. I even use this in my seminars when we are discussing wind and currents.
Also, I only raced the Ruff Rider once, but used this technique on the start of the second day and won the race. So, it works.

Good luck,
Rick

One time sailing in Beaufort NC, it was blowing about 10knots all day long inside the inlet, but near sundown, the air started dying out. We got sucked out towards the ocean for about 5 minutes while there was no breeze. Thankfully a couple of puffs came along, and I was able to get near the banks where theres less current. Skipped from puff to puff back across the inlet to beaufort. Definitely pretty scary.

Also, sailing down around Tybee Island. Jim Stone and I were chatting it up on the beach for a bit to long when he turned around and noticed the clouds to the south were pretty dark. Had to get a move on quick to get back to where we were safe. After you round the last jetty at the entrance to the savannah river, the current is either with you or against you. Thankfully, the river was flat as glass with the current in our favor.

Well, Rick, that is a great idea if you have nice soft, forgiving mangroves along the shoreline. But in my case I had great big rocks, and I wasn't about to pinch and hug.

Well Mary, were you on Rick's boat or yours?

"Well I was just doing what you tell everyone else to do!!! I swear!!!"

My boat, and Rick was miles away on his boat. I braved the current of the inlet alone and resisted the overwhelming temptation to ask one of the many passing jet skis or powerboats to give me a tow. It was a matter of pride to try to make it on my own. And I ultimately did make it through without embarrassing myself too much in front of the fishermen on one side and the rock-and-roll beach crowd on the other side.

Just another comment -- and hint for ultimate success. Another Wave was coming in the channel at the same time, and he did get a tow from a powerboat. Unfortunately, he had the powerboat release him from the tow right on the up-current side of the bridge. He was then in danger again of being sucked back through the bridge by the current. He was there fighting it for quite some time before he was able to make it back to the beach. So the moral is, if you get a tow, make sure you are well away from the tidal drainhole before you release from your towboat.

Okay, since nobody is responding to this post, I have to ask a technical/engineering question: If you are sailing upwind and against a current, is it better to have deep daggerboards, or do deep daggerboards make you more of a victim to the current (more underwater stuff to pull you sideways)?

For instance, in the Hobie Wave, with its minimal lateral resistance, I felt as though I was at mercy of the current. And I thought that if I had more lateral resistance (deeper boards), I could have made better use of the wind and made more ground against the current.

I think this is a very interesting question. Anybody?

Hi Mary,
Oh I wish you hadn't asked that question - it's the biggest source of debate amongst all sailors - cat, mono or otherwise.
First of all, if you are floating in the water which is moving, it doesn't matter which way your boat is facing, how far in or out the boards are, etc. Picture two miniature boats (say, from a Gulliver's Travels scene) racing each other in a bucket of water. Now a boy picks up the bucket and starts walking with it. The effect is EXACTLY the same as current. All the boats are in the same bucket, which is moving. BUT, there is one VERY big difference - that is the apparent wind. The current effects your apparent wind. This is why nearly ALL sailors believe (but for the wrong reasons) that it is always better to have your boat nose-to-current, if possible. They THINK it's because there is less drag on the boat, since a boat sideways to the current must get swept further, right? - NONSENSE! All the boats are in the same moving bucket of water, so it doesn't matter which way they are facing, EXCEPT, that those nose-to-current are getting lifted by the apparent wind generated by the "motion of the bucket" or current, and those sideways to it are getting headed. (If sailing upwind, of course). I have a full detailed explanation of this with diagrams, vectors, etc, if you want. I could E-mail it or try to attach it. I've attached a figure that shows two boats on opposite tacks trying to go upwind in 12 knots of true wind with 0 current and again with 3 kts of current. If you can read this figure you'll see that the boat nose to current gets lifted, while the boat more sideways to it gets headed. It has NOTHING (have I said this enough?) to do with the drag of the underwtaer portions thorugh the water...

Interesting analisys Steve and I agree with it completely but let me offer another way of looking at which may be helpfull. I dont consider the effect the current has as resulting in an apparant wind. I simply view the true wind as modified by the current as the new true wind I'm sailing in. Viewed in this way there is no lift or header effect you discuss. The significant result as I see it is that competator floating in the current is experiencing a different true wind than the race committee anchored to the bottom. This often results in the committee setting a course that is rotated when veiwed from the racer's perspective. No tack is favored by the current but the rotated course requires you to sail more on one tack than the other. Sorry Mary, we digress

Don't apologize for digressing, Dan. It is all very interesting.

Steve, it would be great if you could put the diagrams and vectors on this forum (or e-mail them to me if you can't).

However, I'm not sure how to use this knowledge to get me up the creek faster.

More questions:
Is there some rule of thumb for figuring out in advance whether or not it is even possible to get in against an outgoing tide, depending upon the relative speeds of the current and the wind? If the attempt is doomed from the outset, time would be better spent looking for a tow. Of course, the speed ability of the boat would also be a factor, I assume, so a Tornado would be able to get in with less wind than a Hobie Wave?

Also, concerning the current itself, I know the current is stronger in the middle of a channel than at the sides, but what happens with the current vis-a-vis depth? For instance, if the current is 3 knots on the surface of the water, is the speed incrementally less or greater at various depths below the surface? (Maybe this would depend partly on the shape of the bottom of the channel?)

I can't answer your rule of thumb question Mary but let me offer this on your current question. When a fluid flows over a surface it is slowed by friction. The slowing effect is greatest immediately next to the surface and becomes less as you move away from the surface. This is why your sail experiences stronger wind at the top than the bottom. It is also why the current is slower near the sides of the channel than the middle. The flow in the middle of the channel will be faster with increasing distance from the bottom.

I don't know if this is relevant, but when i kayak up stream against a current, i paddle close 45 degrees off the current direction. I've heard it has to do with bernouli's (sp?) principle but fail to see how. There will be times when it is impossible to paddle up stream, but 45 degrees almost seems to pull me up current.

As for your question on velocity vs depth. Danward is almost right. The air water interface is considered a boundary, though; a fluid fluid boundary is less significant than a fluid solid boundary. So surface water is moving at a slower velocity than say water a couple feet below it. The fastest velocities are actually between the center of the deepest part of the channel and about 3/4 up.

I have found with little to no wind, and a current on your nose.....using my tiller extension to pole my way through a bridge works quite well.....of course the water needs to be shallow enough..........t

That is interesting. Maybe it is that if you are paddling straight into the current, the water is flowing evenly on both sides of the boat. Whereas, if you are paddling forward at a 45-degree angle and are able to at least maintain your position relative to the shoreline, the current sees you an obstacle, much like a rock in a stream, and an eddy forms on the down-current side of your kayak, which tends to, as you said, help lift you forward against the current?

I need help from the physics whizzes.

boat in a bucket...think boat in a bucket. It doesn't matter if or how fast the bucket is moving, the boat has no idea that a current exists. It has no effect on the boat and it feels no additional forces (unless, of course, it's tied up to something stationary). If there is a breeze from the north and the bucket, with the boat in it, is being carried equally as fast to the east, the boat feels the water to be stationary but the wind from the north east. If the bucket is being carried to the south just as fast, the boat feels no wind. Its our visual perspective that leads us to think the boat feels a difference - I have to shake the notion when I'm in the bucket myself!

A boat that can point higher and sail faster will still be the fastest when sailing upwind into a current - boards or no boards. They're all in the same boat...er...I mean bucket.

As to why you can make better headway upstream when paddling at 45 degrees to the current, I have no idea.

Wrinkledpants, I admit that this is not my area of expertise but I'm having trouble believing that the current in Marys channel is being slowed by its contact with the air. The one book I have on the subject indicates that it is not. Prehaps you could provide your source or maybe someone more knowledgeable than I could help here...Dan

Bethwaite covers this subject, I believe...as does CA Marchaj. It's winter, maybe some of y'all would be best served to read up while the weather sucks...

...but I have a scare story. One fine day in lightish air I was traversing the Houston Ship Channel, which is always hairy. I observed two tankers crossing and a dredge barge that appeared to be stationary.

Since it looked ok, I began the crossing. Next thing you know, my tiller stick rivets happened to break so I'm holding the stick in my hand and it ain't attached to the rudders. Being a well-trained boat, my Square headed up like the good girl. I hadn't quite entered the channel, so I took advantage of the rounding-up to try to reattach the tiller stick.

I look up, and lo and behold, the dredge barge is coming at me, wake off its bow, I'm heading for this thing at like 5-6kt or so, I'm at the stern of my Sq and she really likes weight forward to handle well, and I'm rounded up. Welll.... awRITIE then!

My stomach went south. I can't figure why the guys walking around on the barge ain't hollering, nor is the skipper honking at me. Whathafa?

Then, I realise...

I'm drifting DOWN on this barge, the current is that strong, to make a 'wake' on the barge's bow. G.Zeus! And of course, I can't get the Sq to turn back, I gotta head to the channel as the wind is favouring that course. And, of course, there's now some more tankers coming across.

Hell with it. I gotta get some speed, and fast. I drive beam on, hoping I can get enough speed to duck between the boat traffic, still sitting at the back of the bus, the Sq ain't liking none of it.

Finally, about 40 feet before the bow of the barge, I figure I can use the current and head current-ward to get speed, so using current I pass the barge. Once behind the barge, I head across the wind, across the current, and get across the channel. Barely. Didja know that when them big boats blow at you, the whole water vibrates? Or maybe I was just shaking in fear....

sea ya
tami

Jake, you said, "As to why you can make better headway upstream when paddling at 45 degrees to the current, I have no idea."

Isn't water current basically the same thing as air current (wind), except a thicker medium? We are best able to make progress upwind with sails by having approximately a 45-degree angle of attack to the wind current (and most of us don't REALLY understand that one, either.) So why couldn't the same thing be true of a boat hull going through water when being paddled or motored? I would think it would be especially true of a Hobie 16 because of its asymmetrical hulls. If you did not have a sail up and you were paddling a Hobie 16 at a 45-degree angle to the current and depressed the up-current hull enough to get the down-current hull out of the water, wouldn't the boat literally "sail" up-current just as our sails do through the wind current?

Just another of those dumb questions that keep me awake at night. In fact, now I am visualizing an invention of a boat with an underwater profile that will allow it to literally go up a creek without a paddle.

Danward, yes intuitively it wouldn't seem right for velocity to be greatest near the center. I'm a hydrogeology major and am helping my profesor doing research in fluvial systems (river, stream and channel dynamics). As a precursor, we had to mesure stream velocities at differenct depths with a tool resembling a wind vane. If you would like, I can refer you to some geomorphology books that deal specifically with channel dynamics. I apologize, i should have elaborated a bit. It's not the fact that it's a fluid density boundary, but the fact that turbulence results from this density difference. Water flows fastest where there is the least amount of turbulence. Wind causes a slightly different velocity and direction of water on the surface and this creates turbulance. This turbulence acts as a force against the current. If there wasn't any air acting on the surface of the water, what you said would be absolutely correct.

Jake, i guess i'm not sure what you mean by boat in a bucket? If your boat is in the ocean with now wind. There is no force acting on it. You can point the boat in any directin and the boat will not move. But in a channel, the only way to minimize the force of the water is to sail straight up stream. You can easily hang onto your boat when it's pointed up stream, but if you hold your boat side ways to the current you will be dragged downstream. Boards down provides more wetted surface for the current to push on if your angle to the current is anywhere but straight up. I could draw this out and post an attachment if anyone is curious.