HMS Aetna (or HMS Etna) was the mercantile Success launched in 1803 at Littlehampton. The Admiralty purchased here in 1803 to convert her to a Royal Navy bomb vessel. Aetna participated in the second Battle of Copenhagen in 1807 and the Battle of the Basque Roads in 1809. Later, she participated in the attack on Fort McHenry in the Battle of Baltimore and the bombardment of Fort Washington, Maryland in 1814, during the War of 1812. The Navy sold her in 1816 and she returned to mercantile service under her original name. She sailed to Calcutta, to Rio de Janeiro, and more locally until she was wrecked in 1823.