After a shakedown cruise in June–July to the Spanish colony of Puerto Rico and back, the new brig sailed out of New York harbor on 13 September 1842 bound for the Atlantic coast of Africa with dispatches for frigate Vandalia.

After calls at Madeira, Tenerife, and Praia, looking for Vandalia, Somers arrived at Monrovia, Liberia on 10 November and learned that the frigate had already sailed for home.

Wales of a planned mutiny by approximately 20 members of Somers crew, who intended to use the ship for piracy from the Isle of Pines.

[1] On 26 November, Wales notified Captain Mackenzie of the plan through his chain of command via purser H.M. Heiskill and First Lieutenant Guert Gansevoort.

Lt. Gansevoort learned from other crew members that Spencer had been observed in secret nightly conferences with seaman Small and Boatswain's Mate Samuel Cromwell.

Sailmaker's mate Charles A. Wilson was detected attempting to obtain a weapon that afternoon, and Landsman McKinley and Apprentice Green missed muster when their watch was called at midnight.

In response, Mackenzie noted the fatigue of his officers, the ship's small size, and the inadequacies of the confinement as reasons for moving forward with the executions.

However, according to maritime historian Samuel Eliot Morison false accusations that Mackenzie was an incompetent martinet whose brutality brought on the mutiny continued to appear for years afterwards.

Somers was in the Gulf of Mexico off Veracruz at the opening of the Mexican–American War in the spring of 1846, and, except for runs to Pensacola, Florida, for logistics, remained in that area on blockade duty until the winter.

However, a calm wind prevented the Americans from getting their prize out to sea, so they set fire to the vessel and returned through gunfire from the shore to Somers, bringing back seven prisoners.

[4] On 3 March 1847, Congress authorized gold and silver medals to the officers and men of French, British, and Spanish ships-of-war who aided in the rescue.

The story of the Somers Affair and the subsequent trial is dramatized in the penultimate episode of the sixth season of the television series JAG.

The presentation takes place as a dream by Lt. Col. Sarah MacKenzie, while she prepares to give a lecture at the United States Naval Academy, which came into existence as a result of the Somers Affair.