User blog comment:Dentface/Test Server Exclusive - Player-Owned Undead Phantom Ship/@comment-4255152-20130507003128

There was also the Navy Kingfisher, here are two PiratesForums threads:

https://piratesforums.co/threads/pirates-online-new-ship-navy-kingfisher.2195/

https://piratesforums.co/threads/a-pirates-kingfisher.1768/

And an awesome video of the ships:

http://www.youtube.com/watch?v=pzl6dqoDryQ