Frigates And Destroyers Mr. George To ask the Secretary of State for Defence what was the average age of the frigates and destroyers in the Royal Navy for 1990, 1985 and 1980. Mr. Kenneth Carlisle The average age of the destroyer and frigate force on 1 April of each year was as follows: 1980, 11 years and 9 months; 1985, 13 years and three months; 1990, 12 years.