On 5 July, the yacht was running before a gale at 27°10' south, 9°50' west, around 1,600 miles northwest of the Cape of Good Hope. Though the weather was by no means extreme and the vessel was not in any difficulties, a wave struck the yacht and washed away the lee bulwarks. Dudley instantly realised that the yacht was doomed and ordered the single 13-foot lifeboat to be lowered. The "Mignonette" sank within five minutes of being struck and the crew abandoned ship for the lifeboat, only managing to salvage vital navigational instruments along with two tins of turnips and no fresh water. There have been various theories about the structural inadequacies of the yacht that led to such a catastrophic failure in routine weather.