Leila was built to race at the crossroads of yacht racing in Britain. Although she is not as fast as modern fibreglass yachts, she is a key link in the development from working boats.
Boats mechanics are pretty simple. The sails in the wind provide the driving force, whilst the hull in the water induces drag. So if you want to go fast, you need maximum sail and minimum hull – a plank (or windsurfer) with clouds of sail.
However one problem is leeway. In order to sail upwind. you must have a keel in the water to stop her slipping sideways. So the early racing yachts were ‘plank on edge’ to give maximum resistance to leeway but minimum drag through the water.
Another problem is hull speed. Beyond a certain speed, equivalent to about 1.4 times the square root of the waterline length in feet, a boat will try to lift itself out of the water. Effectively for a non-planing hull, this is a maximum speed, although modern yachts regularly exceed it in waves.
To make racing fair, Victorian racing yachts were handicapped on total sail area and water line length. But then some designers built in overhangs on the bow and stern to increase their waterline and speed when heeled, and so started a cat and mouse game between designers and handicappers which still continues to this day.
Plank-on-edge Type abandoned
Prior to 1886 it had been the custom in Great Britain for several reasons to build the yachts deep, narrow, wall-sided, with very heavy lead keels and heavy displacement. The system of measurement had been a tonnage measurement, and under this system designers found, from the knowledge they had then attained from racing trials, that a narrow heavy vessel would beat a wider and lighter craft when both were measured by the tonnage rules. In America this was not the case. There a much lighter and wider form of yacht had been in vogue, having shallower draught and relying upon a centre-board for weatherliness instead of a deep lead keel. Hence in the International contests from 1884 to 1886 for the America’s cup and other events the trials were between deep and narrow British yachts and shallow and broad American yachts. Even in 1867, when G. L. Watson built the ” Thistle,” much broader than ” Genesta ” and ” Galatea,” this vessel was met and defeated by a far wider and shallower American sloop, namely, the ” Volunteer ” above referred to. British yachtsmen claimed that their narrow deep-keeled vessels were more weatherly and better sea-boats than the light American sloops, but racing honours rested with the Americans.
In 1887 the plank-on-edge type was completely abandoned in the United Kingdom. Thenceforward, therefore, the old spirited contests between deep British yachts and shallow American sloops ceased. Whilst Britain abandoned her narrow deep type, America soon also began to modify the old shallow centre-board sloop type, and so between 1887 and 1893 the rival types began to converge very rapidly, until the old idea of a race for the America’s cup being a test of a British type against an American type completely died out. Races sailed for that trophy, after 1887, were less and less trials of opposing national types, but merely contests between British and American designed yachts built upon the same general principle of similar type.
In !892, Leila was built a bit beamier than her plank-on-edge forebears and represented the start of the development of the modern racing yacht.
From Dixon Kemp’s Manual of Yacht and Boat Sailing, eight edition, revised by John Leather, pub. Ashfod Press Publishing 1988.