Originally cutter # 51. She was named for Sebago Lake, built by General Engineering and Drydock at Oakland, California, and launched on 10 February 1930. She destroyed more derelicts than other ships of the class. She transferred to the RN and became HMS "Walney" on 12 May 1941, named after Walney Island. After service as a convpy escort she was prepared for Operation Reservist, an attack on Oran harbour that formed part of Allied invasion of French North Africa She was lost on 8 November 1942 in the assault, her captain awarded the Victoria Cross for his part in pressing on.