Affleck began his nautical career in the service of the
East India Company. He joined the navy at an undetermined date and was promoted acting-lieutenant in 1755. As a lieutenant he served either in the sloop-of-war or the
bomb ketch although as his brother
Edmund was serving at almost exactly the same time the records are a little unclear. At the
Siege of Louisbourg he distinguished himself in leading the boats that cut out the French men-of-war
Prudente and and was promoted to command. His promotion to commander was confirmed on 1 August 1759 and Affleck accompanied
Edward Boscawen in the 18-gun sloop of war to the Mediterranean. On his return to England he was assigned to and sent to India. During the
blockade of Pondicherry on 1 January 1761
Panther was dismasted in a hurricane and once more Affleck impressed his superiors by his calm handling of the situation. In May 1761 he exchanged command of
Panther with Captain Newsom to command the storeship but resigned command of her in early 1762. He then became captain of , which the British had captured some two years earlier at
Pondicherry. Not long thereafter he returned to England. ==HMS
Triumph and the West Indies==