In March 1781 the "Flora" was with the fleet under Vice-Admiral George Darby at the second relief of Gibraltar, and was afterwards sent on to Menorca, in company with the Captain Thomas Pakenham's 28-gun frigate HMS "Crescent", in charge of some victuallers. As they were returning through the Straits off Ceuta on 30 May they met two Dutch frigates of 36 guns, the "Castor" and the "Briel". After a 2¼-hour battle (known as the Battle of Cape St Mary) the "Flora" captured the "Castor" (under Pieter Melvill van Carnbee), but the "Briel" had meantime compelled the "Crescent" to strike her flag; the "Flora" hastened to her consort's assistance, and the "Briel" made her escape. Afterwards, on 19 June, as the two frigates and their prize were broad off Cape Finisterre they fell in with two French 32-gun frigates, "Friponne" and "Gloire". The "Crescent" and "Castor" had been dismasted in the former engagement and were Jury rigged with only 300 unwounded men out of a full complement of 700 over the three ships. The "Castor" had only a prize crew on board, who were unable to leave the pumps. Williams made the signal to separate, and left the "Crescent" and "Castor" easy prizes to the two Frenchmen. His conduct was not blamed and was not even called in question; but Laughton opines that "when we consider that the "Flora"s broadside was nearly as heavy as those of the "Friponne" and "Gloire" together, it is impossible to avoid thinking that Williams did not understand the novel conditions in his favour".