11. She was the test platform for the AN / SQR 19 ( V ) Tactical Towed Array Sonar ( TACTAS ) in 1982. 12. The SYLVER A50 would allow it to fire the-range Aster 30 missile; the towed array sonar would not be fitted. 13. The ships were built for anti-submarine warfare as a primary task even though they are not fitted with towed array sonars . 14. The standard fit for a front line naval ship would include the HUMSA-NG hull mounted sonar and the Nagin towed array sonar . 15. Such tactics have fallen out of use since the advent of the towed-array sonar , which negates the baffles'blind spot. 16. In 1988, the ship became the first to operate a HELTAS Sea King, a Sea King helicopter equipped with passive array sonar . 17. For anti-submarine work, she carried AN / SQS-26 Sonar and the AN / SQR-18 Towed array sonars . 18. During the latter part of 1965 " Hugh Purvis " was adapted for a new conformed planar array sonar at the Boston Naval Shipyard. 19. While the ships are fitted with a Humsa-NG bow-mounted sonar, an Atlas Elektronik towed array sonar set will be fitted in due course. 20. The ships would be called the " Malvinas "-class, and have towed array sonar and an enlarged landing deck to handle Sea King helicopters.
