From Halopedia, the Halo wiki
UNSC Trafalgar was a Punic-class supercarrier in service with the UNSC Navy, serving as the flagship of the Epsilon Eridani Fleet. One of the most revered ships of the fleet, Trafalgar was seen as the pride of the Navy. By the final year of the Human-Covenant War, she was one of the few space worthy supercarriers left in the Navy's fleet. However, Trafalgar was destroyed over Reach in August 2552 when the Covenant attacked the planet.
List of appearances