O Class Destroyers were built for the Royal Navy during the years of 1940 to 1942. The O Class were the first ships in the War Emergency Programme, and were based on the hull and machinery of the preceding J class, but with more sheer forward to counter the poor riding qualities. There were 8 planned & 

O Class Destroyers served between the years of 1940 to 1961

Preceded by:  L and M class

Succeeded by: Q and R class

O Class Destroyers were primarily used as convoy escorts in World War II, and all survived the war. Five of them were involved in the Battle of the Barents Sea, Onslow being badly damaged.