Tern
A 30' 1" Shallow-Draft Sloop
By William Atkin
A Shallow Draft Auxiliary
Tern is the kind of boat many readers have inquired about; a craft useful in shoal water and yet able and comfortable on deep water.

The gaff head sloop rig seems to fit the hull; and, while it may look old fashioned among the tall triangular rigs of our racing fleets, it has its advantages. The sail area is 526 square feet; 383 feet of this being in the main sail; with 142 feet in the jib. There is a short bow sprit; a short mast; and a short main boom. These are blessed in bad weather; and bad weather is sure to overtake you.

The cabin trunk is 10 feet 3 inches long, 6 feet wide at its widest point, and its sides are only 12 inches high. The forward deck is 9 feet 9 inches long thus giving ample working space. The cockpit is 6 feet long by 6 feet 6 inches wide. The floor is, of course, self bailing and extends from the bridge deck bulkhead to the inside of the stern transom and from side to side of the hull. The cockpit seats are set well down in the boat and this gives a feeling of being in the boat, rather than on it. Comforting in rough water.

Below Tern is interesting. Down the companion ladder brings one face to face with that most faithful servant, the gasoline engine. Ten h.p. at 800 turns a minute is ample for power. There it is tucked away under the cockpit and bridge deck; easily accessible while at the same time out of the way. Thanks to the form of the sections aft the shaft angle is moderate indeed. Then the galley with its ice box, sink and range. Opposite a whopping big berth with a row of lockers behind. The center board trunk serves as a pedestal for the saloon table, a leaf being hinged either side as shown. It looks like a comfortable place, this cabin. There is a second berth forward of the galley; this also having its bank of lockers set up behind. The toilet room carries the usual fixtures.
Tern, if you study her lines, will be found to be a big heavy displacement boat. Stiff and yet not bulky. In length over all she is 30 feet 1 inch. Her water line length is 26 feet 6 inches. Her breadth 10 feet, and her draft 3 feet. Her displacement is 12,500 pounds and she carries 4,500 pounds of ballast; 3,200 pounds of lead in the keel, the balance inside. There you have an outline of her principal hull characteristics, and so can judge her capabilities. One of her characteristics is the wide keel. This is my pet idea for getting a wide floor and gaining at the same time an easily driven form below water. If a center board is to be fitted, then the wide keel is indispensable. Because it provides ample room for fastening the frames that come in the way of the trunk, because it prevents any possibility of the center board slot changing width, and because there is ample timber either side of the trunk to prevent wringing. The garboard seams will not leak. The deepest part of the hull is aft. And here it should always be in a shallow draft boat. Because then, if you ground, the bow can be kedged around, or if you know there is a particularly shoal spot ahead you can jump her over it. If you must bump, it is best to take it under the strongest part of the hull, the stern post and heavy deadwoods.
 
PHOTOS OF TERN
Plans for Tern are $100

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