Mermaid-class frigate

Class overview
Built	1760-1763, 1771-1776
Completed	6
General characteristics
Tons burthen	612 72/94 (first batch as designed); 617 22/94 (second batch as designed);
Length	124 ft 0 in (38 m) (gundeck); 102 ft 8.125 in (31 m) (keel - first batch); 103 ft 4.75 in (32 m) (keel - second batch);
Beam	33 ft 6 in (10 m)
Draught	11 ft (3 m)
Sail plan	Full-rigged ship
Complement	200
Armament	UD: 24 × 9-pounder guns; QD: 4 × 3-pounder guns; From 1780; UD: 24 × 9-pounder guns; QD 4 × 6-pounder guns and 18-pounder carronades; FC: 2 × 18-pounder carronades;

The Mermaid-class frigates were a group of six 28-gun sailing frigates of the sixth rate designed in 1760 by Sir Thomas Slade, based on the scaled-down lines of HMS Aurora (originally a French prize, L'Abénaquise, which had been captured in 1757).

The contract for the prototype was agreed on 12 May 1760, for a ship to be launched within twelve months, and her name was assigned as Mermaid on 28 October 1760. The contract for the second ship was agreed on 10 March 1762, for a ship to be launched within thirteen months, and the contract for the third ship was agreed on 2 April 1762, for a ship to be launched within fourteen months; both names were assigned on 30 April 1763.

Some ten years after the design was first produced, it was re-used for a second batch of three ships which were ordered on Christmas Day, 1770. While the design differences from the first batch were minor (the keel was a few inches longer), the second batch were normally designated the Modified Mermaid class.