A moratorium is in effect on adding information from Fire and Blood until December 20th.
Prince Aemon is a war galley of the royal fleet in service at King's Landing. It is a slow ship and long in service.
Prince Aemon is a part of King Joffrey I Baratheon's fleet at the Battle of the Blackwater. The ship and its captain survive the battle, and the captain is honored by the Iron Throne.