The Sphinx-class sailing sixth rates were a series of ten post ships built to a 1773 design by John Williams. Although smaller than true frigates, post ships were often referred to incorrectly as frigates by sea officers, but not by the Admiralty or Navy Board.

The first vessel in the class was launched in 1775, six more in 1776, two in 1777 and the last in 1781. The vessels of the class served in the Royal Navy during the American Revolutionary War. Three of them - Sphinx and Ariel in September 1779, and Unicorn in September 1780 - were captured by the French Navy, but Sphinx was recovered in December 1779 and Unicorn in April 1781. Some survived to see service in the French Revolutionary and Napoleonic Wars.

Ships in class

Name Ordered Builder Begun Launched Completed Fate Sphinx15 April1773Portsmouth DockyardNovember 177325 October1775 29 December 1775Broken up at Portsmouth in June 1811. Camilla15 April1773Chatham DockyardMay 177420 April1776 9 July 1776Sold to be broken up in April 1831. Daphne15 April1773Woolwich DockyardAugust 177421 March1776 25 May 1776Sold at Sheerness in May 1802. Galatea15 April1773Deptford DockyardOctober 177421 March1776 26 May 1776Broken up at Sheerness in April 1783. Ariadne10 April1775Chatham DockyardMay 177527 December1776 23 February 1777Sold at Chatham in August 1814. Vestal1 August1775Plymouth DockyardFebruary 177623 May1777 9 July 1777Lost with all handsin a gale off Newfoundland in October 1777. Perseus30 October1775John Randall, RotherhitheNovember 177520 March1776 26 May 1776at Deptford DockyardBroken up at Sheerness in September 1805. Unicorn30 October1775John Randall, RotherhitheNovember 177523 March1776 25 May 1776at Woolwich DockyardBroken up at Deptford in August 1787. Ariel3 July1776John Perry, BlackwallJuly 17767 July1777 12 August 1777at Woolwich DockyardTaken by the French Navy on 10 September 1779. Narcissus8 January1777Plymouth Dockyard13 June 17779 May1781 20 June 1781Wrecked off the Bahamas in October 1796.

References

Rif Winfield, British Warships in the Age of Sail, 1714-1792: Design, Construction, Careers and Fates, Seaforth Publishing, Barnsley (2007). .