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48' Ketch
"HIAWATHA"
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Starb'd Aft Perspective | Starb'd Forward Perspective | Larger Side Perspective | Under Sail - Aft Perspective
Copyright 2011 Michael Kasten
The following is an outline of how the prototype design of the 48' Ketch "Hiawatha" has been developed. This is an adaptation of a much larger prototype, the "120' Chief Seattle" based on the Grand Banks fishing schooners of the early 20th century, but developed for construction in aluminum.
The large fishing schooners of the Northeast at that time were often named after Native American chieftains. True to the schooners of the time, this prototype bears the name of a prominent Native American. According to legend, "Hiawatha" was a key founder of the Iroquois Nation in the 1400's - a nation which still exists today. It is not known whether Hiawatha was mythical or real, however no one questions the wisdom that is attributed to him in making peace among the tribes of the Iroquois.
As is the case with the classic fishing schooners, the 48' Hiawatha has a hull form well suited to the schooner rig. Possibly it could be similar to the 44' Redpath... an easily handled rig for a small schooner. Indeed, the original 120' prototype Chief Seattle was developed as a "tern" schooner using raked Bermuda type sails.
For Hiawatha the task was instead to investigate the use of an easily handled ketch rig, very much in keeping with two other classics presented here, the 42' Zephyr and the 56' Shiraz.
RESEARCH and INSPIRATION
Much like the much larger Chief Seattle, the 48' Hiawatha has a profile and hull shape similar to the well-known Grand Banks fishing schooner, Bluenose, which was built circa 1920 at Halifax, Nova Scotia. As noted in the book "American Fishing Schooners" by Howard Chapelle, "... the Bluenose was built to race and to fit the official measurements for competitors in the International Fishing Schooner Races, and her fitness for fishing, though required, was relatively superficial."
At 143 feet length on deck, the original Bluenose was one of the fastest schooners on the Grand Banks, winning nearly all of the races she entered. Several schooners of a similar size were designed and built in New England during the 1920's for the express purpose of trying to beat the Bluenose, but... They could not beat her even though many schooners tried...!
As such, Bluenose and the racing-fishing schooners of her time (late 1800's to early 1900's) represent the height of the development of commercial sail. Size for size, these were the fastest commercial sailing vessels ever built, and they were also the most windward-capable. The last of these schooners were built in 1927 - displaced at last by steam.
HULL FORM
The model shown here is heavily based on the Bluenose, but is much smaller and has been proportioned accordingly in order to take advantage of the best that the Grand Banks schooners had to offer.
The Bluenose had very well balanced waterlines, fore and aft. In other words, the counter stern was sufficiently narrow as to avoid a wedge shaped underbody when heeled. This prevents the stern from being lifted when heeled, thus avoiding the steering anomalies present in wedge shaped hull forms.
Notably, the Bluenose had very easy and slightly convex waterlines forward, thereby avoiding any possible added drag induced by the tendency of hollow forward waterlines to create a second bow-wave. The Bluenose diagonals were very fair without any tendency to form a hook astern. The buttock lines on Bluenose were very easy and fair forward, with a long straight run aft extending into a long counter stern with heavily raked transom.
The refined counter stern, combined with the long bow overhang support the vessel well at speed when bow and stern wave rise, providing a heeled waterline that is much longer than the static waterline. The combination of these factors is indicative of a fast sailing machine. The Bluenose was a true greyhound of the seas.
The keel on the Bluenose was relatively short, with a knuckle roughly one third of the WL aft, and having moderate drag to the keel bottom - thereby having reduced wetted surface as compared to vessels of the day, yet providing an underwater profile conducive to excellent directional stability at sea. The long easy entry profile forward offers excellent handling down-wind, with no tendency to "gripe" when reaching the trough of a wave, as often is the case with a deep forefoot. As has been reported, handling under sail is excellent with this hull form.
All of these features have been retained in the 48' Hiawatha prototype shown here.
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ALUMINUM CONSTRUCTION...?
Wooden craft require that the rabbet along the lower edge of the garboard plank be more or less parallel to and not too distant from the keel bottom. This is for several reasons, not the least of which is to structurally reinforce the "blade" of the keel, especially aft where it is deep. This was also beneficial in that the rabbet did not have to cross the deadwood timbers in the keel, which would have invited leaks and would therefore have required numerous stop-waters along the rabbet. This meant that there had to be a strong "reverse" curvature at the turn of the garboard, so that the planking could extend downward to the rabbet line, approximately parallel to the keel bottom.
Since the Hiawatha has been planned for construction in in aluminum, there is no need structurally for there to be a "reverse" curvature to the garboard in order to support the keel, nor to carry the garboard / rabbet down onto the keel aft in order to prevent leaks. Thus on the prototype presented here, the rabbet at the keel is able to follow the simple projection of the deadrise onto the upright face of the keel. This allows vastly simpler construction in metal and increases the effective "lateral plane" of the keel. Further, we are able to retain the same overall keel profile as the original Bluenose, but provide a NACA foil shape for the sake of increased lift and greatly reduced drag.
Displacement of our prototype as-modeled is quite adequate to carry the structure, equipment, outfit, fuel, and rig. Particulars are as follows:
- Length on Deck: 48 ft.
- Beam on Deck: 12.75 ft.
- Waterline Length: 35.4 ft.
- Waterline Beam: 12 ft.
- Draft: 6.25 ft.
- Displacement: 39,086 lb.
- Disp. / Length: 392
SAIL RIG
The rig I've proposed is much the same as the 36' Grace, the 42' Zephyr, and the 56' Shiraz. As shown, the rig is as simple as it can be made for the sake of sailing short-handed. The mizzen, main sail and the stays'l are loose footed, with booms. Coming about, the only sail to handle is the jib. In light airs, a larger jib / genoa can be added, and / or the hard pulling "mule" as the mizzen stays'l is often called on a ketch.
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INTERIOR LAYOUT
At 48 feet on deck a comfortable layout for two is possible, with four others able to be accommodated if needed. The helm and cockpit are just aft of the mizzen mast, the perfect spot to spread an awning over the mizzen boom. The ketch rig lends itself well to having a long low cabin trunk. In this case, the interior, starting forward, is planned as follows:.
- Large forepeak for lines, fenders, and anchor gear.
- Master stateroom with "island" type of double berth so both sleepers can swing their feet out, but both are well-contained above hip level.
- Two large settee berths, which are basically planned as comfortable sofas with a low coffee table in between, convertible into a dining table.
- A well equipped galley to port with ready access to the social are immediately forward of the galley.
- A spacious head / shower to starb'd of the galley.
- A chart desk to port just aft of the galley, with seating on the forward end of a quarter berth located aft.
- Hanging locker opposite the chart desk, just aft of the head.
- Quarter berths on each side, extending aft below the bridge deck.
- Engine box on center below the bridge deck, arranged to have the appearance of a large bureau, and well-insulated.
- Large lazarette aft for storage and spares.
GENERAL NOTES
The classic Grand Banks type that I've chosen as a paradigm is from the height of the development of commercial sail. The last of these racing-fishing schooners were in fact built as yachts, even though they had to do at least a few trips to the Grand Banks to fish so that they could qualify for the International Fishing Schooner Races..! In my view these are very inspiring craft, the likes of which have rarely been seen since.
Inevitably, one might argue in favor of a split keel / skeg arrangement to reduce wetted surface. Although unseen above the WL, and therefore un-noticed, possibly that could be viewed as a natural step in the evolution of the type. Whether a full keel or combined keel & skeg were used, there is no doubt this would be a fast and weatherly vessel - and one with an unquestioned pedigree among classic yachts.
SUMMARY
As we have written previously in the Spring 1999 Editorial for the Metal Boat Quarterly, the materials of construction need not dictate the aesthetic presentation of a yacht. In the case of this vessel, the intent is to create a period-correct vessel in all but the materials of construction. In so doing, it is not necessary copy the details of exactly how such a vessel would have been built at the time, especially with regard to materials and structure.
Since we now have much stronger materials, a better knowledge of naval architecture, and vastly more robust analysis tools, we can make generous use of these technologies. Examples of new materials include the use of galvanized steel wire for standing rigging, Dacron for running rigging and sails, nylon for anchor rode, and... aluminum for spars and for hull structure - vastly stronger and much lighter.
In order to create a convincing period-correct "modern classic" design it is important to be sensitive to the aesthetics of the type, the general hull and deck arrangement, the presentation of the hull, its profile and elements of style right down to the carvings - yet not be so pedantic as to be opposed to marrying diverse hull and rig - as long as they seem to be a "good fit" aesthetically and functionally.
Inevitably, the question of authenticity comes up. In the Spring 1997 Editorial for the Metal Boat Quarterly we have outlined this rationale, summarized briefly as follows:
We have to keep in mind that the US colonial and post-revolutionary sailing vessels were made of what was most readily available on the East coast of the Americas at that time: wood. Today the situation is much different. We now have much easier access to metal than we have to wood.
Perhaps in order to approach the whole concept of building a highly traditional sailing vessel in the very most traditional of ways, we should ask our selves: "Would the colonial owner-skipper, keenly interested in turning a profit, have even remotely entertained the notion of building a vessel out of a more expensive, more difficult to find, more labor intensive, and weaker material?"
Without question, the answer would be a resounding "No!"
The aluminum hulled early 1900's vessel we have planned here will not only look like the real thing, it will in fact be the real thing.
It just won't be built in wood...!
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