by Tad Roberts, Naval Architect, Vancouver BC
[Excerpted from Spring 2025 CYA Classic Yachting]
Last time we looked at some fantail sterns so now let’s move to the forward end of the boat for a look at bows and why they are shaped the way they are. For the CYA Fleet, there are really four possible bow profiles: the plumb stem, the raked stem, the spoon bow, and the clipper bow. While the plumb stem is certainly the most common, the other three have been adopted at times by different builders and designers for diverse reasons.
The stem has an obvious primary structural role, holding the forward halves of the hull together and as a strong point should the boat collide with anything. It also plays an aesthetic part in establishing the vessels character: the massive vertical upright of an old tug or the long graceful reverse curves of a Herreshoff clipper bow. Finally the stem shape has significant impact on resistance and seakeeping performance stemming from the forward waterline and topsides shape.
From the 1800’s through WWII, the plumb (vertical) stem was standard on motoryachts and commercial vessels of all sizes. It was simple and effective, creating the longest waterline for a given overall length, and the finest entrance angle (lowest resistance). Stylistically its minimalism offered good balance to the often straight sheer lines and vertical transoms of the period. While the fine forward topsides were easy to plank, the shape didn’t lift when driven into a wave at any speed greater than about 7 knots. So designers and builders started to create wider deck shapes with more flair.
As these wider deck lines and greater flair in the topsides (associated with greater speed) became fashionable, the flair meant twisting topside planks to meet the vertical stem, and to ease the poor builder’s job, the raking stem was introduced. Widely adopted in the 1950’s by builders such as Chris-Craft and designers like Edwin Monk and John L. Hacker, the raking stem was an indication that this was a fast, modern, and powerful vessel. The downside was shorter waterlines and blunter entrance angles, increasing resistance at low speed and pushing builders to install high-horsepower, short-lived auto based gas engines, to push boats through the bow wave and up to planing speeds (image below).
The spoon bow is also an older shape, with its roots in ancient history. Up until the 1960’s it was almost universal on sailing yachts and quite common on fishing vessels. The well-known 1897 built BC sailing yacht Dorothy is a great example of an older spoon bow, as is the schooner Bluenose. William “Billy” Atkin designed many spoon bowed sailing and power boats. The spoon bow offers relative ease in planking like a raked stem, and gets some buoyancy well forward to gradually lift the bow when meeting a wave (image below).
The heavily stylistic clipper bow is probably the most complex stem shape, and certainly it’s the most elegant when well executed. With possible roots in sailing ships of the 17 and 1800’s, the shape has been around a long time, but due to its complexity and apparent fussiness, has never been widely adopted. Good examples are seen on many of William Garden’s powerboats from the 1960’s, and the 1939 Robert Allan motor yacht Fifer. The clipper has the benefit of being fine down low and wide up at the deck where volume (buoyancy) is wanted. The main cost is in construction complexity and difficulty to repair should that be required.
So while stem shape goes a long way in setting a vessel’s character, its importance in structural and resistance/sea keeping functions carry equal weight.
