Chieftains were tanks in service with the armed forces of the United Kingdom.
Several Chieftains were used against the Racnoss incursion on Christmas Eve 2007. The tanks opened fire on the webstar of the Empress of the Racnoss, after receiving authorisation from Harold Saxon. The attack was successful, as the ship's power was depleted, and the target was completely destroyed. (TV: The Runaway Bride)