Fly was a development of the Orestes-class ship-sloop designed by Professor Inman of the School of Naval Architecture.

In December 1841 she commissioned at Plymouth under the command of Francis Price Blackwood to survey the Torres Strait in company with the cutter Bramble.

[5] During this part of her service she employed the painter and draughtsman Harden Sidney Melville to produce the first official hydrographic survey of the north-east coast of Australia.

[6] On 2 September 1844, she rescued the survivors of the British merchant ship Lady Grey, which had been wrecked on Alert's Reef the previous day with the loss of a passenger whilst on a voyage from Sydney, New South Wales to Singapore.

[5] Fly returned to the United Kingdom, arriving at Spithead on 19 June 1846 and proceeded to Plymouth to pay off.