When they entered service, the Type 21s were criticized for being under-armed in relation to their size and cost. A program was put in hand to increase their firepower by fitting four French-built MM38 Exocet anti-ship missiles. These were sited in front of the bridge screen aft of the forecastle, displacing the Corvus countermeasure launchers to amidships. This improvement was quickly carried out to all ships of the class except "Antelope" and "Ambuscade"; the latter was fitted with Exocet in 1984/85. The Exocets were located in two pairs and the missiles would deploy across the ship and clear the opposite side of the vessel to their launchers in flight.