During the rest of the war he served in the Surprise frigate, and in March 1755 was appointed to the Monmouth, a small ship of 64 guns, which, after two years in the Channel, was, early in 1767, sent out to the Mediterranean under the command of Captain Arthur Gardiner.
He was then appointed to the Hussar frigate, and commanded her at home and in the West Indies till 23 May 1762, when she struck on a reef off Cape Français of St. Domingo, and was lost, her officers and men becoming prisoners of war.
In July 1769 he commissioned the Lowestoft, and again spent the greater part of his time at Pensacola, where his duties seem to have been promoting the welfare of the settlement and cultivating vegetables.
Of Carkett's personal courage there can be no doubt, but his experience with fleet was extremely small, and of naval tactics he knew nothing beyond the rule for the line of battle laid down in the fighting instructions.
‘All the satisfaction I received,' he complained to the secretary of the admiralty on 23 July 1780, ‘was his acknowledgment that he had informed their lordships that I had not properly obeyed his signals in attacking the enemy rear’ (Beatson, Nav.
Rodney's letter did in fact, contain a very severe reprimand, of which Carkett made no mention, but requested the secretary of the admiralty to lay his explanation before their lordships.
Whether he ever received an answer is doubtful, for the Stirling Castle, which had been sent to Jamaica, and thence ordered home with the trade, was, in a violent hurricane on 5 October, totally lost on Silver Keys, some small rocks to the north of Cape Français.