Lucas was commissioned lieutenant on 19 November 1778.
He commanded the fireship Salamander 8 at the Battle of the Saintes on 12 April 1782, having been promoted commander and appointed to her the month previously. Following the battle he was posted captain on 14 April, whereupon he recommissioned the recaptured Ardent 64. After setting sail for England with Rear-Admiral Thomas Graves convoy the un-seaworthy Ardent was returned to Port Royal before her consorts were decimated in the Central Atlantic Hurricane of September, and then having eventually reached England the Ardent formed part of an escort to a convoy sailing for Jamaica at the end of the year.. She eventually returned to Portsmouth with another convoy from Jamaica in February 1783, being in company with the Hydra 20, Captain Isaac Coffin.
After remaining unemployed throughout the years of peace he recommissioned the Sphinx 20 in March 1793 for the Irish station, and on 12 January 1794 he captured the French corvette Trompeuse 18 off Cape Clear. He then left the Sphinx in the autumn of 1794.
In March 1795 Lucas joined the thirty-year-old Arrogant 74, sailing for the Cape of Good Hope with Rear-Admiral Sir George Keith Elphinstone’s squadron in April in place of Captain James Hawkins Whitshed after that officer had stated a preference to remain in home waters. He commanded this vessel at the capture of the Cape on 16 September before proceeding to join the East Indies squadron. Being in company with the Victorious 74, Captain William Clark, he later sought an action with five French frigates and an armed vessel under the orders of Rear-Admiral Pierre César Guillaume Sercey on 8 September 1796 off Sumatra, but was largely seen off the next day, although not without having savaged the Vertu 36. From the French point of view Sercey willingly discontinued the action in order to preserve his frigates for their main purpose of commerce raiding.
Lucas died on 7 July 1797 whilst still commanding the Arrogant in the East Indies.
His widow, Elizabeth, died early in the following year.