Trans RINA, Vol 152, Part A4, Intl J Maritime Eng, Oct-Dec 2010
is a section offering advice for selecting the proper shape of a life-boat, with specific reference to the avoidance of broaching-to [31]:
“The curvature of the keel has however been demonstrated to be the principal or only error in the construction of the vessel and we would recommend to those who in future may construct such vessels to preserve the spheroidal form of the body of the boat, yet, so as to leave a straight keel and a sufficient quantity of gripe to hinder the boat from broaching to, on receiving the stroke of the waves on her ends.”
In his 1826 guide for the shipbuilders of the time, Partington recommends the use of sliding keels as a means for avoiding broaching-to [32]:
“… no misfortune, similar to that of broaching to, can ever befall a vessel furnished with sliding keels.” We learn more about these keels from another passage referring to a 66 ft vessel:
“She has three sliding keels inclosed in a case or well; they are each 14 ft in length; the fore and the after keels are 3 ft broad each, and the middle keel is 6 feet broad. The keels are movable by means of a winch, and may be let down 7 feet below the real keel; and they work equally well in a storm as in still water.”
In a discussion at the Institution of Civil Engineers, Captain Hosken replies to the Society’s President that he doesn’t believe the steam ship “Great Britain” to be more liable to broaching-to than other ships when scudding [33]:
“His opinion was founded upon experience in the Great Western. The same question had been put to him by old seamen, before the first voyage of that vessel, when, from that ship’s great length, it was thought there would be more than usual difficulty in steering her:”. In his lectures of 1846 on naval architecture, Gardiner Fishbourne argues for selecting a less
fine stern
compared to the bow (as known today, shifting the centre of hydrodynamic reaction towards the stern improves directional stability) [34]:
“The reason why short vessels do not run well.- It is notorious that vessels with fine after bodies, particularly if they be short, run badly. It is because there is so little action in the after body in such case, for the water cannot turn in upon it, there is even a danger in such vessels of their broaching to against their helm. The after body then should be greater than the fore body, in some ratio inverse of this action of the water.”
Notwithstanding these deliberations, in another article of the Journal “The Life-Boat” (published in 1855) no clue could be offered for ship design [25]:
“In reply to the question, as to whether any particular
kinds of boats are more liable than others to broach-to, the answers given are so conflicting and contradictory as
to afford no information on the point.” 4.4 MORE LITERARY SOURCES
Besides Falconer’s poem, reference to broaching-to has appeared also in several other literary texts:
In “Arthur Gordon Pym”, a nautical story written in the early literary life of Edgar Alan Poe, one comes across the following passage [35]:
“The boat was going through the water at a terrible rate- full before the wind-no reef in either jib or mainsail- running her
bows completely under thousand wonders she did not broach to”.
In Charles Reade’s novel “Love me Little, Love Me Long” Jack easies down Lucy’s worries while on board [36]:
“No I tell you miss; all we have got to mind is two things: we must not let her broach-to, and we must not get
pooped.”...”But I mean, what could be the
consequence of-broaching-to?” Jack opened his eyes in astonishment. “Why, the sea will run over her quarter, and swamp her.”
And later: “But oh! Mr. Dodd, there is another danger. We may
broach-to.” “How can she broach-to when I am at the helm? Here is the arm that won’t let her broach-to”.
4.5 NARRATIVES In his memoirs, Lieut. John Harriott writes in 1808 with
reference to a trip from St. John’s (Newfoundland) to Gibraltar [37]:
“For several days we continued thus, depending on the man at the helm to guard against the ship’s broaching- to.”
Telling his experience of travel by sea from New
Brunswick to Quebec, Moses Guest provides a dramatic account of feelings on board as his ship has broached-to [38]:
“… finding we could not, with any degree of safety, lay to any longer, we commenced scudding, under a close reefed foresail but soon found we could only scud under our bare poles, which we continued to do until 6 A.M.. The vessel then broached to, and lay with her broad side to the wind, in the trough of the sea (which is the most dangerous situation that a vessel can be in:) a most tremendous sea was rolling down upon us, which we expected would soon swallow us up. I shall never forget
foam. It was
A-170
©2010: The Royal Institution of Naval Architects
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