All were manned exclusively by CRNVR personnel. These ships were meant to sweep and guard the approaches the harbors but were often used on extended missions outside Ceylon waters. In the course of these operations, the ships came under enemy fire, recovered essential information from Japanese aircraft that were shot down, sailed to Akyab after the Burma front was opened in two FMVs for harbour duties and, was called upon to accept the surrender of the Italian light cruiser Eritrea and escort her to port with a prize crew on board.
All were manned by CRNVR personnel exclusively. These ships were meant to patrol and guard harbor entrances but frequently ventured beyond Ceylon's waters for extended periods. In the course of these operations, they faced enemy fire, recovered vital information from Japanese aircraft that crashed, sailed to Akyab after the Burma front was opened up in two FMVs for harbour duties, and were called upon to accept the surrender of the Italian light cruiser Eritrea and escort her to port with a prize crew on board.