Astute SPEARFISH - The heavyweight torpedo armament of the VANGUARD Class Strategic Submarines and the TRAFALGAR Class Fleet Submarines are to be deployed on the ASTUTE Class of Fleet Submarines from later this year and then they will be truly operational   The SPEARFISH first entered service in 1994 and is due to equip the new class of SUCCESSOR Class of Submarine which is due to enter service c. 2028.