TRAWLERTALK
Anchors Aweigh from a High Bow Trawler By Captains Chris and Alyse Caldwell
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nchoring from a high bow trawler has its moments— moments aside from what the rest of us experience each time we drop...uh...lower the hook. If you think being 10 feet above the water only means adding 10 feet to your scope equation, then you might want to think again…or just read on for some more great trawler tricks and tips. We’ll even help you through the awkward mooring line retrieval from the skyscraper heights of a trawler’s deck. Everyone knows that to sleep safely at night while anchored, you do not want the anchor to drag or pop out of the sea floor. Add a wind or tide change, and you are almost guaranteed that the anchor will also change direction in the sea floor, pivot and, hopefully, reset. Hopefully. Please understand that there are many key elements which can make a captain comfortable when sleeping on the hook. Proper anchor type for the sea floor conditions is the first and most obvious decision. Mud, sand or rock bottoms call for different anchor designs. Too many of us use the anchor that came with the boat. The boat dealer put it there, so it must be the right anchor, right? Wrong. Our second decision is where to anchor considering weather conditions, wind or waves, Jet Skis or salsa music. And our third decision is the scope or the length of rode of the anchor line in relation to the height from the bow roller to the sea floor. Each of these decisions affect how well our anchors hold, and therefore, how well we sleep. Now we need to ask, just how do you manage all this from the high bow of an oceangoing trawler?
News & Views for Southern Sailors
Captain Chris hanging from the bow pulpit of a Hatteras Long Range Cruiser. The dock is two feet off the water and Chris is 2 1/2 feet off the dock. He is six feet tall , and another 2 feet with his arms over his head, which is 12 1/2 feet off the water. Wow!
Lots of questions already, so now let’s get to some of the answers and why height matters. Standard procedure for anchoring is to locate your ideal anchorage; approach the spot into the dominant force, either wind or current. Keep in mind your swinging radius. Again, here we are thinking about that high ocean-going bow. The scope formula for a traditional rode is to use seven times the distance from the bow roller to the sea floor at high tide. The trawler’s high bow becomes a concern when making your rode much longer and thus your swinging radius much greater. Beware that you don’t swing and kiss a neighboring boat, or worse yet, ground your trawler during a low tide change. This really becomes an issue when in 7- or 8-foot tidal areas like Georgia. Let’s do the math. Water depth is 10 feet, and a scope of 7 means you need to deploy 70 feet of rode. But wait! The bow is 10 feet above the water so we need to add another 10 feet to the formula, which means we now have to consider 10 feet of depth plus 10 feet of air space equals 20 feet times our 7 scope equaling 140 feet of rode. But wait! There’s more! What if you are in Georgia with a 7-foot tide? Now you must consider the highest tide for scope purposes and the extended swinging radius while at low tide. So add another 7 feet to your scope formula if you anchored at low tide. Your new calculation now includes 10-foot depth plus 10-feet air space plus 7-foot tidal range. This is now 27 feet x 7 scope—equaling 189 feet of rode deployed. Whew! No worries say you? Hmmm. When that summer SOUTHWINDS March 2013
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