Azure, a castle embattled argent, masoned sable, portcullis or, above which the symbol of St. John the Evangelist - art eagle, wings displayed, inverted, a nimbus around the head and supporting a closed book with the sinister foot, all gold.
(Glossary of Heraldic Terms)
This ship derives its name from the Porte St. Jean of Quebec City. It is located on the Rue Saint Jean and was opened in 1667 in honour of the Evangelist. This badge displays the generic gateway for all Porte class vessels. The eagle holds a book representing the Gospels - one of the symbols associated with Saint John the Evangelist.
Porte-class gate vessel
White and azure blue
Badges Of The Canadian Navy by Arbuckle, J. Graeme. Halifax: Nimbus Publishing, 1987.