The Thrasymachus was a luxury liner from the 44th century that Amy Pond and Rory Williams honeymooned on.
As the ship entered the cloud belt of an unamed planet it was in trouble of crashing and Kazran Sardick was prepared to let it do so, however the Eleventh Doctor eventually convinbced him to allow the ship to land on the planet and Amy, Rory and the rest of the crew and passengers were saved. (DW: A Christmas Carol )