Trans RINA, Vol 152, Part A4, Intl J Maritime Eng, Oct-Dec 2010
almost a matter of certainty that the boat will broach to broadside to the sea and be capsized.”
In Folkard’s “The Sailing Boat”, and under the rather unsurprising heading “Causes of ship capsizing” is given another view of broaching-to [28]:
“The action of the sea upon a boat running into a heavy surf, may be thus described: - when on the top of a heavy wave or roller, the bows are lifted high out of the water; then, as the sea recedes, the boat is hurled forward, and the bows are buried under water; when the sea acting powerfully on her head and fore gripe, twists her round, broadside to the waves, called “broaching to;” and the sea then runs over the gunwale into the boat; the next motion that inevitably follows, is a heavy lurch on the other side and another sea breaks completely over, and fills or capsizes the boat. This may happen either under sail or oars. There is considerable difficulty in preventing a boat from broaching to, when stem and stern are alternately lifted out of the water by the waves; and should the boat broach to and meet a very heavy roller, broadside on, the chances are fifty to one that she will be swamped.”
drogues in the English coasts at the middle of the 19th century. He considers them to be somehow shorter (about 4 ft 6 inches) in comparison to our earlier description.
Enlightening for the modern reader is the ensuing passage from Folkard about
the widespread use of
“Drogues are now a good deal used on the Eastern Coast, in both sailing and rowing boats; they serve to check the boat's way, and keep her end on to the waves; and are, therefore, of great assistance to the crew, in preventing the boat from broaching to. Experience teaches, that when a heavy breaker follows the boat up astern, it is useless to attempt running away from it: then a question naturally arises, what must be done on the impulse of the moment. “For your lives men! back her astern; hard at it every one of you! and let the man in the stern-sheets creep forward a moment, to lighten the boat's stern!” By this effort the wave strikes the boat kindly, and passes on; but if allowed to follow her up astern, so surely as such an experiment is tried, the sea will either curl over the stern, or the boat will broach-to and take it over the gunwale.
Multiple (“series”) drogues are present as drag devices on sailing boats even in our days. They are intended for use when heavy weather is encountered [29].
In a manual for naval cadets (1860), drawing possibly upon his experiences from the Royal Navy, Mc-Neill- Boyd advises
the young cadets of the time about
broaching-to and the proper tactics for avoiding it [30]. We are informed also that drogues were commonly used by boatmen at the Norfolk coast. It is remarkable that in the paragraph below he is alluding firstly to the condition of surf-riding and then to the condition of bow diving:
“ But if a boat on being overtaken by a heavy surf, has not sufficient inertia to allow it to pass her, ..., - her stern is raised high in the air and the wave carries the boat before it, on its front, or unsafe side, sometimes with frightful velocity, the bow all the time deeply immersed in the hollow of the sea, where the water, being stationary or comparatively so, offers a resistance, whilst the crest of the sea, having the actual motion which causes it to break, forces onward the stern, or rear end of the boat. A boat will in this position sometimes, aided by careful oar steerage, run a considerable distance until the wave has broken and expended itself. But it will often happen that, if the bow be low it will be driven under water, when the buoyancy being lost forward, whilst the sea presses on the stern, the boat will be thrown (as it is termed) end over end; or if the bow be high, or it be protected, as in some life-boats, by a bow air chamber, so that it does not become submerged, that the resistance forward acting on one bow will slightly turn the boat's head, and the force of the surf, being transferred to the opposite quarter, she will in a moment be turned round broadside by the sea and be thrown by it on her beam- ends, or altogether capsized. It is in this manner that most boats are upset in a surf, especially on flat coasts, and in this way many lives are annually lost amongst merchant seamen when attempting to land after being compelled to desert their vessels.”
Informative is his advice for managing a situation where broaching-to is imminent, for a boat operating with oars near to a shore. He proposes to follow one of three distinctive operational practices:
1st. By turning a boat's head to the sea before entering the broken water, and then backing in stern foremost, pulling a few strokes ahead to meet each heavy sea and then again backing astern. If a sea be really heavy and a boat small, this plan will be generally the safest, as a boat can be kept more under command when the full force of the oars can be used against a heavy surf than by backing them only.
2nd. If rowing to shore with the stern to seaward, by backing all the oars on the approach of a heavy sea, and rowing ahead again as soon as it has passed to the bow of the boat, thus ,rowing in on the back of the wave; or, as is practised in some lifeboats, placing the after-oarsmen, with their faces forward, and making them row back at each sea on its approach.
3rd. If rowed in bow foremost, by towing astern a pig of ballast or large stone, or a large basket, or a canvass bag termed a “drogue” or drag, made for the purpose,
the
object of each being to hold the boat's stern back and prevent
her being turned broadside to the sea or
broaching-to.” 4.3 SHIP DESIGN In the 1816 edition of the Encyclopaedia Perthensis there
©2010: The Royal Institution of Naval Architects
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