Johnstone sailed on his expedition from Spithead on 13 March 1781 in command of 46 ships, including five ships of the line (the 74-gun , the 64-gun , and the 50-gun ,  and ), four frigates (the 38-gun HMS Apollo, the 36-gun ,  and the 28-gun ), the fireship  and the bomb vessel . He also had seven light armed cruisers, two cutters and a sloop to serve as despatch vessels, four transports, eight storeships, and thirteen Indiamen.
Johnstone's expedition in 1781 involved a diverse fleet of ships: five warships (the 74-gun , the 64-gun , and the 50-gun ,  and ), four frigates (the 38-gun HMS Apollo, the 36-gun ,  and the 28-gun ), a fireship, and a bomb vessel. He also had seven light armed cruisers, two cutters, and a sloop for dispatch duties.