This should be an exciting voyage, From http://en.wikipedia.org/wiki/Cape_Horn

Shipping hazards
Several factors combine to make the passage around Cape Horn one of the most hazardous shipping routes in the world: the fierce sailing conditions prevalent in the Southern Ocean generally; the geography of the passage south of the Horn; and the extreme southern latitude of the Horn, at 56° south. (For comparison, Cape Agulhas at the southern tip of Africa is at 35° south; Stewart Island/Rakiura at the south end of New Zealand is 47° south.)
The prevailing winds in latitudes below 40° south can blow from west to east around the world almost uninterrupted by land, giving rise to the “roaring forties” and the even more wild “furious fifties” and “screaming sixties”. These winds are hazardous enough in themselves that ships traveling east would tend to stay in the northern part of the forties (i.e. not far below 40° south latitude); however, rounding Cape Horn requires ships to press south to 56° south latitude, well into the zone of fiercest winds.[16] These winds are further exacerbated at the Horn by the funneling effect of the Andes and the Antarctic peninsula, which channel the winds into the relatively narrow Drake Passage.
The strong winds of the Southern Ocean give rise to correspondingly large waves; these waves can attain enormous size as they roll around the Southern Ocean, free of any interruption from land. At the Horn, however, these waves encounter an area of shallow water to the south of the Horn, which has the effect of making the waves shorter and steeper, greatly increasing the hazard to ships. If the strong eastward current through the Drake Passage encounters an opposing east wind, this can have the effect of further building up the waves.[17] In addition to these “normal” waves, the area west of the Horn is particularly notorious for rogue waves, which can attain heights of up to 30 metres (100 ft).[18]
The prevailing winds and currents create particular problems for vessels attempting to round the Horn against them, i.e. from east to west. Although this affects all vessels to some extent, it was a particularly serious problem for traditional sailing ships, which could make very little headway against the wind at the best of times;[19] modern sailing boats are significantly more efficient to windward and can more reliably make a westward passage of the Horn, as they do in the Global Challenge race.
Ice is a hazard to sailors venturing far below 40° south. Although the ice limit dips south around the horn, icebergs are a significant hazard for vessels in the area. In the South Pacific in February (summer in Southern Hemisphere), icebergs are generally confined to below 50° south; but in August the iceberg hazard can extend north of 40° south. Even in February, though, the Horn is well below the latitude of the iceberg limit.[20] These hazards have made the Horn notorious as perhaps the most dangerous ship passage in the world; many ships were wrecked, and many sailors died, attempting to round the Cape.

According to this website (about 3/4 of the way down), “Valiant” is a 97′ fantail Yacht. According to it’s website, it mainly cruises between New York, New Jersey and Connecticut.

There is also the Valiant from Doctor Who which is an airborne aircraft carrier.

Did Mordred cross out Valiant himself or did he get someone else to do it or just a coinkidink?