Corvettes are specialist Escort craft, usually slightly smaller and less powerful than true Frigates, but slower and more heavily armoured than Raiders. Typically constructed rapidly in times of war, Corvettes utilise simple components and rugged designs. Their normal mission profile is to escort vulnerable transports, protecting them against light Raiders, thus freeing more valuable true Frigates to accompany Battleships and Cruisers. Corvettes are unpopular with Imperial Navy officers. Most Imperial battlefleets tend to have many parochial and conservative tendencies, and receiving orders to nursemaid civilian vessels in a newly-constructed and untested warship is seen as demeaning, or even as a calculated insult. Despite this, the Corvettes have upheld the traditions of the Imperial Nav