Originally ordered in April 1847 as a "Screw Schooner", she was suspended in August 1847 and re-ordered on 1 November 1850 to the same design as HMS Cruizer.

The wooden sloops of the Cruizer class were designed under the direction of Lord John Hay, and after his "Committee of Reference" was disbanded, their construction was supervised by the new Surveyor of the Navy, Sir Baldwin Walker.

Her two-cylinder horizontal single-expansion steam engine, which was supplied by James Watt & Company at a cost of £5,450, generated an indicated horsepower of 233 hp (174 kW); driving a single screw, this gave a maximum speed of 7.75 knots (14.35 km/h; 8.92 mph).

[2] The Hornet's commander at the time, Charles Codrington Forsyth, noted in the ship's log: We could discern no dangers lying off them and the waters appear to be deep close to the shore.

[2] On 20 July 1860 Hornet recommissioned for service on the Cape of Good Hope Station under Commander William Buller Fullerton Elphinstone.