The Porcupine-class sailing sixth rates were a series of ten 24-gun post ships built to a 1776 design by John Williams, that served in the Royal Navy during the American War Of Independence.

Some survived to serve again in the French Revolutionary and the Napoleonic Wars.

The 1776 design enlarged the ship, which permitted the mounting of an eleventh pair of 9-pounder guns on the upper deck and two smaller (6-pounder) guns on the quarterdeck.

The Admiralty ordered ten ships to this design over a period of two years.

The contract price for each was £10½ per ton BM; they were named Porcupine and Pelican by Admiralty Order on 27 August 1776.